Methods of treating inherited retinal diseases

Abstract

The present invention relates to the treatment of inherited retinal diseases using stem cell therapy. In particular, the present disclosure relates to methods of using photoreceptor precursor cells to treat primary photoreceptor diseases via surgical administration to the eye of a subject.

Description

Attorney Docket No.: 132042-5007-WOMETHODS OF TREATING INHERITED RETINAL DISEASESCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims the benefit of and priority to U. S. Patent Application No. U. S. 63 / 726,123, filed on November 27, 2024; U. S. 63 / 748,850, filed on January 23, 2025; U. S.63 / 786,676, filed on April 10, 2025; and U. S. 63 / 884,465, filed on September 19, 2025; entitled “METHODS OF TREATING INHERITED RETINAL DISEASES,” each of which are incorporated herein by reference in their entirety.FIELD

[0002] The present disclosure relates generally to the field of cellular-based therapy. More particularly, it concerns methods of treating inherited retinal diseases (IRDs) using photoreceptor precursor (PRP) cells.BACKGROUND

[0003] Primary photoreceptor diseases are a subgroup of inherited retinal diseases that include retinitis pigmentosa and cone-rod dystrophies. These diseases affect the structure and function of the photoreceptor cells in the retina, leading to irreversible vision loss in both children and adults. Current treatments for primary photoreceptor disease are mostly supportive and primarily limited to the use of specialized low-vision aids such as eyeglasses, magnifiers, adaptation devices, and services for the blind. Thus, there remains a significant unmet medical need for patients with loss of photoreceptor cells.SUMMARY

[0004] The present disclosure addresses the above need by providing methods for treating an inherited retinal disease in a subject in need thereof by administering photoreceptor precursor cells to a subretinal space of the subject’s eye.

[0005] In an aspect, described herein is a method of treating an inherited retinal disease in a subject in need thereof by administering a therapeutically effective amount of a composition comprising photoreceptor precursor cells to an eye of the subject in need thereof.Attorney Docket No.: 132042-5007-WO

[0006] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells is surgically administered to the eye of the subject.

[0007] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells is surgically administered into a subretinal space of the eye of the subject.

[0008] In some embodiments, a subretinal injection that comprises the therapeutically effective amount of the composition comprising photoreceptor precursor cells is surgically administered into the subretinal space of the eye of the subject.

[0009] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered as a single dose.

[0010] In some embodiments, the subject is a human.

[0011] In some embodiments, the human is at least 18 years of age.

[0012] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells includes between about 0.5*106to about 5.0* 106photoreceptor precursor cells.

[0013] In some embodiments, the subject is additionally administered one or more immunosuppressive agents. In a further embodiment, one or more immunosuppressive agents are administered to the subject beginning about two or about three weeks prior to administration of the therapeutically effective amount of the composition comprising photoreceptor precursor cells.

[0014] In some embodiments, one or more immunosuppressive agents are selected from the group consisting of: tacrolimus, mycophenolic acid, prednisone, locally administered dexamethasone, and difluprednate.

[0015] In some embodiments, one or more immunosuppressive agents are administered to the subject for about 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55 or more weeks after the administration of the therapeutically effective amount of the composition comprising photoreceptor precursor cells.

[0016] In some embodiments, the composition comprising photoreceptor precursor cells includes (e.g., do not substantially include) rod cells and / or cone cells.Attorney Docket No.: 132042-5007-WO

[0017] In some embodiments, the photoreceptor precursor cells are derived from human induced pluripotent stem cells.

[0018] In some embodiments, the photoreceptor precursor cells are allogeneic.

[0019] In some embodiments, the inherited retinal disease affects a function and / or structure of a retina in the eye of the subject.

[0020] In some embodiments, the inherited retinal disease is a primary photoreceptor disease.

[0021] In some embodiments, the primary photoreceptor disease is selected from the group consisting of retinitis pigmentosa, Usher Syndrome, cone-rod disease, rod-cone disease, cone dystrophy, and cone-rod dystrophy.

[0022] In some embodiments, the subject has diminished vision due to cellular loss of rod cells and / or cone cells.

[0023] In some embodiments, the method of treating results in a change in retinal structure in the eye in the subject.

[0024] In some embodiments, the change in retinal structure is an increase in thickness of an outer retinal layer. In further embodiments, the thickness of the outer retinal layer is measured by spectral domain optical coherence tomography or by fundus autofluorescence.

[0025] In some embodiments, the photoreceptor precursor cells differentiate and / or mature into cells that exhibit one or more of the following properties: form inner segments, form outer segments, express opsin, or traffic rhodopsin to outer segments by rods.

[0026] In some embodiments, the method of treating leads to reformation of an outer nuclear layer.

[0027] In some embodiments, the method of treating improves visual function and / or functional vision in the subject, wherein the subject is human.

[0028] In some embodiments, e.g., after a human subject has received treatment as described herein via the administration of (a composition comprising) photoreceptor precursor cells, e.g., at a dose described herein, visual function and / or functional vision is improved where, as compared to baseline, the human exhibits one or more of (or at least one of): a mean retinal sensitivity greater than or equal to seven decibels as measured by microperimetry, light sensitivity improvement as measured by full-field stimulus testing, a clinically significant improvement inAttorney Docket No.: 132042-5007-WOretinal sensitivity as measured by static perimetry, a best corrected visual acuity (BCVA) greater than or equal to 0.3 Logarithm of the Minimum Angle of Resolution (Log AR) units and > 15 Early Treatment of Diabetic Retinopathy Study (ETDRS) letter score, optionally wherein the human has a BCVA at baseline between about LogMAR 3.9 to about LogMAR 0.5 in a study eye and / or has an ETDRS letter score at baseline of 60 or less in the study eye, a low luminance visual acuity (LLVA) greater than or equal to 0.3 LogMAR units and > 15 ETDRS letter score, a clinically significant improvement in retinal sensitivity as measured by dark-adapted static perimetry, a clinically significant improvement in fixation location as measured by microperimetry, a clinically significant improvement in fixation stability as measured by microperimetry, a clinically significant improvement in color vision as measured by Hardy Rand and Rittler pseudoisochromatic test, a clinically significant improvement in quality of life scale scores as measured by the Michigan Retinal Degeneration Questionnaire (MRDQ) and / or the Michigan Vision-related Anxiety Questionnaire (MVAQ), an ability to navigate a multi-luminance navigation test, and / or an ability to navigate a multi-luminance navigation test at least two illumination levels lower. The human subject may exhibit any one or more of the effects above after receiving treatment for an inherited retinal disease as described herein, after receiving treatment for vision loss as described herein, and / or after receiving (a composition comprising) photoreceptor precursor cells in method of increasing a thickness of an outer nuclear layer of a retina as described herein.

[0029] In an aspect, provided herein is a method of treating vision loss in a human in need thereof, the method comprising administering a therapeutically effective amount of one or more immunosuppressive agents to the human and administering a therapeutically effective amount of a composition comprising photoreceptor precursor cells to a subretinal space of an eye of the human.

[0030] In some embodiments, the therapeutically effective amount of one or more immunosuppressive agents is administered to the human about two to about four weeks (e.g., about 2, 3, or 4 weeks) prior to administration of the therapeutically effective amount of the composition comprising photoreceptor precursor cells.

[0031] In some embodiments, the therapeutically effective amount of one or more immunosuppressive agents is administered to the human for about 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55 or more weeks after administration of the therapeutically effective amount of the composition comprising photoreceptor precursor cells.Attorney Docket No.: 132042-5007-WO

[0032] In some embodiments, one or more immunosuppressive agents are selected from the group consisting of tacrolimus, mycophenolic acid, prednisone, locally administered dexamethasone, and difluprednate.

[0033] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered as a single dose.

[0034] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered to one eye of the human.

[0035] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered to both eyes of the human.

[0036] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells is surgically administered to the human.

[0037] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells includes between about 0.5* 106to about 5.0* 106cells.

[0038] In some embodiments, the human is treated with a therapeutically effective amount of the composition comprising photoreceptor precursor cells if the human: is at least about 18 years of age, has a confirmed genetic diagnosis of primary photoreceptor disease, has a BCVA between about LogMAR 3.9 to about LogMAR 0.5 in a study eye, has an ETDRS letter score between about 20 and about 60 in the study eye, exhibits regions of ellipsoid zone (EZ) loss with preservation of inner nuclear layer (INL) and retinal pigment epithelium (RPE) layer in regions of EZ loss in the retina, has clear ocular media and adequate pupil dilation in both eyes, has serological evidence of prior Epstein-Barr virus infection, or a combination thereof.

[0039] In some embodiments, the human is not treated with a therapeutically effective amount of the composition comprising photoreceptor precursor cells if the human: has a history or current evidence of scleritis, endophthalmitis, recurrent idiopathic or autoimmune-associated uveitis or vitritis, ocular herpes simplex virus infection, retinal detachment, amblyopia, nystagmus, glaucoma or other significant optic neuropathy, diabetic macular edema or diabetic retinopathy, cystoid macular edema that is or could be treated with carbonic anhydrase inhibitors, spherical equivalent refractive error of greater than 8.00 diopters myopia, recent ocular surgery, significant ocular trauma, clinically relevant cataract, clinically relevant vitreomacular adhesion or traction, epiretinal membrane, macular pucker, macular hole, disorders of the ocular media, prior vitreoretinal surgery, monocular vision, tuberculosis infection, recent immunosuppressive therapy,Attorney Docket No.: 132042-5007-WOuncontrolled diabetes, previous treatment with cell therapy, gene therapy, or retinal implant, recent investigational therapy, or bone marrow or solid organ transplant; wherein the human does not have a presence of narrow iridocorneal angles contraindicating pupillary dilation, an intraocular pressure (IOP) >21 mmHg, a known allergy to tacrolimus, mycophenolic acid, corticosteroids, basiliximab, or to their ingredients, a contraindication to general anesthesia or to undergoing a surgical procedure, an active ocular inflammation or infection, cancers or pathology of the central nervous system which may alter visual function, cause vision loss, or limit vision recovery, an active malignancy, or a current active bacterial, fungal, or viral infection; wherein the human is not currently taking one or more lOP-lowering medications and is not currently pregnant; and optionally, wherein the human does not express anti-photoreceptor precursor cell H LA antibodies, or the human does not express one or more of anti-photoreceptor precursor cell HLA-C antibodies, anti-photoreceptor precursor cell HLA-DPB1 antibodies, and / or anti-photoreceptor precursor cell HLA-DR antibodies.

[0040] In an aspect, provided herein is a method of increasing a thickness of an outer nuclear layer of a retina of a human subject, the method comprising surgically administering a composition comprising a therapeutically effective amount of a composition comprising photoreceptor precursor cells to a subretinal space of an eye of the human subject.

[0041] In some embodiments, the thickness of the outer nuclear layer is measured by spectral domain optical coherence tomography or by fundus autofluorescence.

[0042] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered as a single dose.

[0043] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered to one eye of the subject.

[0044] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered to both eyes of the subject.

[0045] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells includes between about 0.5x106to about 5.0x106cells.

[0046] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells includes rod cells and / or cone cells.

[0047] In some embodiments, the photoreceptor precursor cells are derived from human induced pluripotent stem cells.Attorney Docket No.: 132042-5007-WO

[0048] In some embodiments, the photoreceptor precursor cells differentiate and / or mature into rod cells and / or cone cells.BRIEF DESCRIPTION OF THE OF THE DRAWINGS

[0049] The foregoing summary, as well as the following detailed description, will be better understood when read in conjunction with the appended figures. For the purpose of illustration, shown in the figures are embodiments. It should be understood, however, that the summary, detailed description, and figures are not limited to the precise arrangements, examples, and instrumentalities shown.

[0050] Figure 1A-1O: Representative OCT images after BRT-A administration in Foxn1-S334ter Rat. 1A-1C) Eye treated with 2*105of BRT-A cells at 1, 3, and 6 months post dose, respectively; 1 D-1 F) Eye treated with 4* 105of BRT-A cells at 1, 3, and 6 months post dose; 1 G-11) Eye treated with 8x105of BRT-A cells at 1, 3, and 6 months post dose; 1J-1L) Eye treated with VCA at 1, 3, and 6 months post dose; 1M-1O) untreated eye at 1, 3, and 6 months post dose. Black arrows identify replacement ONL / transplanted cell areas. White arrows identify surgical damage in an eye treated with 2*105of BRT-A cells and an eye treated with VCA. Scale bar represents 100 pm and is applied to the top image in each panel; enlarged images are provided underneath to highlight transplant regions.

[0051] Figure 2A-2C: Comparison of pupillary responses between treatment groups to red and blue light flashes of different intensities after BRT-A administration in Foxn1-S334ter rat. At 2A) Baseline (pre-dose), 2B) Day 80, and 2C) Day 165. Low, med (medium), and high refer to light intensity. Mean data are shown. Error bars indicate the standard error of the mean (SEM). Statistical significance is denoted as *p<0.05.

[0052] Figure 3A-3C: Average estimated total number of engrafted rods (Ku80+ NRL+), cones (Ku80+ MEF2C+), MEF2C and NRL double-positive cells, other retinal cells (Ku80+ MEF2C-NRL-), combined photoreceptors, and total human cells per eye at 1, 3, and 6 months in 3A) Eyes treated with 2X105of BRT-A cells, 3B) Eyes treated with 4X105of BRT-A cells, and 3C) Eyes treated with 8x105of BRT-A cells. Error bars indicate the standard error of the mean (SEM). Statistical significance levels are denoted as: *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001.

[0053] Figure 4A-4C: Average percentage of rods (NRL+), cones (MEF2C+), MEF2C and NRL double-positive cells, total photoreceptors, and other retinal cells per eye within the total engrafted cell population at 1-, 3-, and 6-months post dose in 4A) Eyes treated with 2X105of BRT-A cells,Attorney Docket No.: 132042-5007-WC4B) Eyes treated with 4x105of BRT-A cells, and 4C) Eye treated with 8x105of BRT-A cells. Error bars indicate the standard error of the mean (SEM). Statistical significance levels are denoted as: *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001.

[0054] Figure 5A-5F: Ki67 analysis at 1, 3, and 6 months after BRT-A administration in Foxnl-S334ter Rat. 5A-B) Average estimated total Ki67+ cells per eye (5A) and percentage of Ki67+ cells within the total engrafted cell population (5B) at 1, 3, and 6 months post dose in eyes treated with 2x 105of BRT-A cells; 5C-D) Average estimated total Ki67+ cells per eye (5C) and percentage of Ki67+ cells within the total engrafted cell population (5D) at 1, 3, and 6 months in eyes treated with 4x105of BRT-A cells; and 5E-F) Average estimated total Ki67+ cells per eye (5E) and percentage of Ki67+ cells within the total engrafted cell population (5F) at 1, 3, and 6 months in eyes treated with 8x105of BRT-A cells. Error bars represent the standard error of the mean (SEM). Statistical significance levels are denoted as follows: *p<0.05, **p<0.01, ***p<0.001.

[0055] Figure 6A-6F: PHH3 Analysis at 1, 3, and 6 months after BRT-A administration in Foxnl-S334ter rat. A-B) Average estimated total PHH3+ cells per eye (6A) and percentage of PHH3+ cells per eye within the total engrafted cell population (6B) at 1, 3, and 6 months post dose in eyes treated with 2X105of BRT-A cells; 6C-D) Average estimated total PHH3+ cells per eye (6C) and percentage of PHH3+ cells within the total engrafted cell population (6D) at 1, 3, and 6 months in eyes treated with 4x105of BRT-A cells; and 6E-F) Average estimated total PHH3+ cells per eye (6E) and percentage of PHH3+ cells within the total engrafted cell population (6F) at 1, 3, and 6 months in eyes treated with 8x105of BRT-A cells. Error bars indicate the standard error of the mean (SEM). Statistical significance level is denoted as *p<0.05.

[0056] Figure 7A-E: depicts a panel of graphs showing representative flow cytometric analyses of BRT-A measuring HI_A Class II expression (y-axis) and HLA Class I expression (x-axis) for 7A) untreated cells, 7B) cells treated with 100 pg / mL IFN-y and 20 pg / mLTNFa, 7C) cells treated with 1 ng / mL IFN-y and 200 pg / mL TNFo, 7D) cells treated with 10 ng / mL IFN-y and 2 ng / mL TNFa, and 7E) cells treated with 100 ng / mL IFN-y and 20 ng / mL TNFa.

[0057] Figure 8A-D: depicts a panel of graphs showing representative flow cytometric analyses of BRT-A measuring HLA Class I expression (y-axis) and HLA Class II expression (x-axis) for 8A) untreated cells, 8B) cells treated with 100 ng / mL IFN-y, 8C) cells treated with 100 ng / mL TNFa, and 8D) cells treated with 100 ng / mL IFN-y and 20 ng / mL TNFa.

[0058] Figure 9A-E: depicts a panel of graphs showing representative flow cytometric analyses of BRT-A measuring side scatter (y-axis) and either pan-HLA Class II expression (x-axis, top) orAttorney Docket No.: 132042-5007-WOand HLA-DR expression (x-axis, bottom) for 9A) untreated cells, 9B) cells treated with 100 pg / mL IFN-y and 20 pg / mL TNFa, 9C) cells treated with 1 ng / mL IFN-y and 200 pg / mL TNFa, 9D) cells treated with 10 ng / mL IFN-y and 2 ng / mL TNFa, and 9E) cells treated with 100 ng / mL IFN-y and 20 ng / mL TNFa.DETAILED DESCRIPTION

[0059] Provided herein are methods of treating inherited (e.g., genetic) retinal diseases (e.g., a primary photoreceptor disease such as retinitis pigmentosa, Usher Syndrome, cone-rod disease, rod-cone disease, cone dystrophy, or cone-rod dystrophy, etc.) using photoreceptor precursor cells (PRPs). Such methods may comprise administering an amount (e.g., a therapeutically effective amount) of photoreceptor precursor cells to an eye of a subject in need thereof, such as a human. Advantageously, the methods disclosed herein may be used to compensate for a lack or diminution of photoreceptor cell function to treat inherited retinal diseases such as a primary photoreceptor disease and thus provide for improved vision.Definitions

[0060] Definitions of certain terms to be used herein are provided. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as is commonly understood.

[0061] As used herein, the terms "cell", "cell line", and "cell culture" may be used interchangeably and all such designations include the progeny thereof.

[0062] The terms “cell dissociation” or “dissociation” refer to providing a cell composition containing cell aggregates or aggregated cells and separating the aggregated cells into singularized cells and / or reduced-size cell aggregates. Cell dissociation may be mechanical, physical, enzymatic, chemical, or any combination thereof. In an example, cell dissociation may be induced via incubation with TrypLE™ (Thermo Fisher Scientific, Waltham, MA, Catalog No.: A1217701). Cell dissociation may further involve agitation, vortexing, trituration, or mixing in order to break cell aggregates apart.

[0063] The terms “cells in aggregates,” “aggregated cells,” “aggregates,” “clumps,” or “cell aggregates” refer to cells associated with one another by means of intercellular adhesion or other mechanisms of association. In some embodiments, a cell suspension may comprise aggregated cells.

[0064] The term "cell population" or “cell composition” is used herein to refer to a group of cells. The cell population can be derived from a common progenitor or may comprise more than oneAttorney Docket No.: 132042-5007-WOcell type. An "enriched" cell population refers to a cell population derived from a starting cell population (e.g., an unfractionated, heterogeneous cell population) that contains a greater percentage of a specific cell type than the percentage of that cell type in the starting population. The cell populations may be enriched for one or more cell types and depleted of one or more cell types.

[0065] The term “clinical significance” or “a clinically significant improvement,” used interchangeably herein, may be used to quantify treatment effectiveness, set clinical practice guidelines, and / or interpret trial results. The term relates to the practical importance of a treatment effect. For example, a clinically significant improvement may measure whether a treatment has a real genuine, palpable, noticeable effect on daily life of a patient or subject. A measure of clinical significance may differ based on the measurement, test, readout, protocol, trial, and / or patient outcome being assessed. Clinical significance may be measured by any methods know in the art for the corresponding measurements, tests, readouts, protocols, trials, and / or patient outcomes. Clinical significance may be an objective or subjective measure.

[0066] The phrase “composition of cells comprising photoreceptor precursor cells” refers to a cell population wherein the composition comprises at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or about 100% PRP cells.

[0067] The term "differentiation" or “maturation” refers to the process by which an unspecialized cell becomes a more specialized type with changes in structural and / or functional properties. The mature cell typically has altered cellular structure and tissue-specific proteins.

[0068] As used herein, "essentially" or "essentially free," in terms of a specified component, is used herein to mean that none of the specified component has been purposefully formulated into a composition and / or is present only as a contaminant or in trace amounts. The total amount of the specified component resulting from any unintended contamination of a composition is therefore well below 0.05%, preferably below 0.01%. In some embodiments, no amount of the specified component can be detected with standard analytical methods.

[0069] The terms "individual," "host," "subject," “participant,” and "patient" are used interchangeably herein, and refer to a mammal, including, but not limited to, human and nonhuman primates, including simians and humans; mammalian sport animals (e.g., horses); mammalian farm animals (e.g., sheep, goats, etc.); mammalian pets (dogs, cats, etc.); and rodents (e.g., mice, rats, etc.). Preferably, the mammal is a human.Attorney Docket No.: 132042-5007-WO

[0070] The term "induced pluripotent stem cells (iPSCs)" are cells generated by reprogramming a somatic cell by expressing or inducing expression of a combination of factors (herein referred to as reprogramming factors). iPSCs can be generated using fetal, postnatal, newborn, juvenile, or adult somatic cells. In certain embodiments, factors that can be used to reprogram somatic cells to pluripotent stem cells include, for example, Oct4 (sometimes referred to as Oct 3 / 4), Sox2, c-Myc, and Klf4, Nanog, and Lin28. In some embodiments, somatic cells are reprogrammed by expressing at least two reprogramming factors, at least three reprogramming factors, or at least four reprogramming factors to reprogram a somatic cell to a pluripotent stem cell.

[0071] The terms “inherited retinal disease” or “IRD” refer to a clinically and genetically diverse group of disorders characterized by outer retina degeneration and / or dysfunction. IRDs may involve impaired or complete loss of function of photoreceptor cells, leading to irreversible blindness. Some IRDs may be non-syndromic and affect only the eyes, whereas others may be considered syndromic, affecting the eyes as well as other organs. IRDs may include, but are not limited to retinitis pigmentosa, Usher Syndrome, cone-rod disease, rod-cone disease, cone dystrophy, cone-rod dystrophy, and achromatopsia.

[0072] An "isolated" cell has been substantially separated or purified from others cells in an organism or culture. Isolated cells can be, for example, at least about 99%, at least about 98% pure, at least about 95% pure, or at least about 90% pure.

[0073] The term "neural retinal progenitors," or " NRPs," refers to cells which are restricted in their differentiation potential to neural retina cell types.

[0074] The term “outer nuclear layer,” or “ONL,” refers to the light-detecting portion of the eye in a vertebrate. The ONL may include rod cell nuclei, cone cell nuclei, both rod and cone cell nuclei, or neither rod nor cone cell nuclei.

[0075] The term “outer retinal layer” refers to a layer of the retina that includes the ONL, as well as other layers such as the outer plexiform layer (OPL), the Henle fiber layer, the myoid and ellipsoid zone (MEZ), and the photoreceptor outer segments (OS).

[0076] The terms "photoreceptor precursor cells," “photoreceptor progenitor cells,” " PRP cells,” or “PRPs” refer to cells differentiated from embryonic stem cells or induced pluripotent stem cells which can differentiate into photoreceptor cells that expresses the cell marker rhodopsin or any of the three cone opsins, and optionally express the rod or cone cyclic guanosine monophosphate (cGMP). PRP cells do not express or have substantially no expression of CRALBP, BEST1,Attorney Docket No.: 132042-5007-WOIGFBP5, C0L8A1, ELN, UPK3B, TPM2, PTGDS, SERPINE3, TIMP3, MITF, and / or PMEL17. Additionally, PRP cells have low or substantially no expression of PAX6, CHX10, TYRP1, Ki67, and / or ONECUT1. The photoreceptors may be rod and / or cone photoreceptors. The plasma membrane of a photoreceptor cell contains two compartments: outer segments and inner segments. The term “outer segments” refers to a specialized compartment of rod and / or cone photoreceptor cells where phototransduction (e.g., capture of light and its conversion into electrical signals) takes place. The term “inner segments” refers to the compartment of the rod and / or cone cells where metabolism and membrane potential regulation occurs. The term "pluripotent" refers to the property of a cell to differentiate into all other cell types in an organism, with the exception of extraembryonic, or placental, cells. Pluripotent stem cells are capable of differentiating to cell types of all three germ layers (e.g., ectodermal, mesodermal, and endodermal cell types) even after prolonged culture. A pluripotent stem cell may be an embryonic stem cell derived from the inner cell mass of a blastocyst. In other embodiments, the pluripotent stem cell may be an induced pluripotent stem cell derived by reprogramming somatic cells. The terms “primary photoreceptor disease” or “PPD” refer to a subclass of inherited retinal diseases that include degenerative and non-degenerative diseases. Examples of degenerative PPDs may include retinitis pigmentosa, Usher Syndrome, cone-rod disease, rod-cone disease, cone dystrophy, and cone-rod dystrophy. Examples of non-degenerative PRDs may include achromatopsia. PPDs may be non-syndromic or syndromic and may be familial or sporadic.

[0077] The term "purified" does not require absolute purity; rather, it is intended as a relative term. Thus, a purified population of cells is greater than about 90% 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% pure, or, preferably, essentially free of other cell types.

[0078] The term "retinal pigment epithelium" refers to a layer of pigmented cells between the choroid, a layer filled with blood vessels, and the neural retina.

[0079] The term "retinal progenitor cells", also called "retinal precursor cells" or " RPCs", encompass cells which are competent for generating all cell types of the retina, including neural retina cells, such as rods, cones, photoreceptor precursor cells, as well as cells which can differentiate and / or mature into retinal pigment epithelium (RPE) cells.

[0080] The term "stem cell" refers herein to a cell that under suitable conditions is capable of differentiating into a diverse range of specialized cell types, while under other suitable conditions is capable of self-renewing and remaining in an essentially undifferentiated pluripotent state. The term "stem cell" also encompasses a pluripotent cell, multipotent cell, precursor cell andAttorney Docket No.: 132042-5007-WOprogenitor cell. Exemplary human stem cells can be obtained from hematopoietic or mesenchymal stem cells obtained from bone marrow tissue, embryonic stem cells obtained from embryonic tissue, or embryonic germ cells obtained from genital tissue of a fetus. Exemplary pluripotent stem cells can also be produced from somatic cells by reprogramming them to a pluripotent state by the expression of certain transcription factors associated with pluripotency; these cells are called "induced pluripotent stem cells" or "iPSCs".

[0081] A "therapeutically effective amount" used herein refers to the amount of a compound or cells (e.g., PRPs) that, when administered to a subject for treatment of a disease or condition, is sufficient to affect such treatment. As used herein, the term “effective amount” means that dose of a composition comprising PRP cells that will elicit the biological or medical response of a tissue, system, animal, or human that is being sought, for instance, by a researcher or clinician. Furthermore, the term “therapeutically effective dose” means any dose that, as compared to a corresponding subject who has not received such dose, results in improved treatment, healing, or amelioration of a disease, disorder, or side effect, or a decrease in the rate of advancement of a disease or disorder. The term also includes within its scope doses effective to enhance normal physiological function. Therapeutically effective amounts and treatment regimens are generally determined empirically and may be dependent on factors, such as the age, weight, and health status of the subject and disease or disorder to be treated. Such factors are within the purview of the attending physician.

[0082] The terms "treatment" and "therapy" and the like, as used herein, are meant to include therapeutic as well as prophylactic, or suppressive measures for a disease or disorder leading to any clinically desirable or beneficial effect, including but not limited to alleviation or relief of one or more symptoms, regression, slowing or cessation of progression of the disease or disorder. Thus, for example, the term treatment includes the administration of an agent prior to or following the onset of a symptom of a disease or disorder thereby removing one or more signs of the disease or disorder. As another example, the term includes the administration of an agent after clinical manifestation of the disease to combat the symptoms of the disease. Further, administration of an agent after onset and after clinical symptoms have developed where administration affects clinical parameters of the disease or disorder, whether or not the treatment leads to amelioration of the disease, comprises "treatment" or "therapy" as used herein. Moreover, as long as the compositions of the disclosure either alone or in combination with another therapeutic agent alleviate or ameliorate at least one symptom of a disorder being treated as compared to that symptom in the absence of use of a composition comprising PRP cells, theAttorney Docket No.: 132042-5007-WOresult should be considered an effective treatment of the underlying disorder regardless of whether all the symptoms of the disorder are alleviated or not.

[0083] As used herein, "undifferentiated" refers to cells that display characteristic markers and morphological characteristics of undifferentiated cells that clearly distinguish them from terminally differentiated cells of embryo or adult origin.Induced Pluripotent Stem Cells (iPSCs) and Photoreceptor Precursor Cells

[0084] Somatic cells can be reprogrammed to produce induced pluripotent stem cells (iPSCs) using methods known to one of skill in the art. One of skill in the art can readily produce induced pluripotent stem cells; see for example, Published U. S. Patent Application No. 2009 / 0246875, Published U. S. Patent Application No. 2010 / 0210014; Published U. S. Patent Application No.20120276636; U. S. Patent No. 8,058,065; U. S. Patent No. 8,129,187; U. S. Patent No. 8,278,620; PCT Publication NO. WO 2007 / 069666 A1, and U. S. Patent No. 8,268,620, which are incorporated herein by reference.

[0085] With the exception of germ cells, any somatic cell can be used as a starting point to make an iPSC. For example, cell types could be keratinocytes, fibroblasts, hematopoietic cells, mesenchymal cells, liver cells, or stomach cells. T-cells may also be used as a source of somatic cells for reprogramming. There is no limitation on the degree of cell differentiation or the age of an animal from which cells are collected; even undifferentiated progenitor cells (including somatic stem cells) and finally differentiated mature cells can be used as sources of somatic cells in the methods disclosed herein. The somatic cell itself may be a PRP cell, such as a human PRP cell. The PRP cell can be an adult or a fetal PRP cell. iPSCs can be grown under conditions that are known to differentiate human ES cells into specific cell types, and express human ES cell markers including, for example, SSEA-1, SSEA-3, SSEA-4, TRA-1-60, and / or TRA- 1-81.

[0086] Generally, nuclear reprogramming factors may be used to produce pluripotent stem cells from a somatic cell. For example, cells may be treated with a nuclear reprogramming substance, which may be generally one or more factor(s) capable of inducing an iPSC from a somatic cell or a nucleic acid that encodes these substances. The nuclear reprogramming substances generally include at least Oct3 / 4, Klf4 and Sox2 or nucleic acids that encode these molecules. A functional inhibitor of p53, L-myc or a nucleic acid that encodes L-myc, and Lin28 or Lin28b or a nucleic acid that encodes Lin28 or Lin28b, can be utilized as additional nuclear reprogramming substances. Nanog can also be utilized for nuclear reprogramming.Attorney Docket No.: 132042-5007-WO

[0087] As disclosed in U. S. Patent No. 8,900,871, exemplary reprogramming factors for the production of iPSCs include (1) Oct3 / 4, Klf-4, Sox2, L-Myc (Sox2 can be replaced with Sox1, Sox3, Sox15, Sox17 or Sox18; Klf4 may be replaceable with Klf1, Klf2 or Klf5); (2) Oct3 / 4, Klf4, Sox2, L-Myc, TERT, SV40 Large T antigen (SV40LT); (3) Oct3 / 4, Klf4, Sox2, L-Myc, TERT, human papilloma virus (HPV16 E6; (4) Oct3 / 4, Klf4, Sox2, L-Myc, TERT, HPV16 E7 (5) Oct3 / 4, Klf4, Sox2, L- Myc, TERT, HPV16 E6, HPV16 E7; (6) Oct3 / 4, Klf4, Sox2, L-Myc, TERT, Bmil; (7) Oct3 / 4, Klf4, Sox2, L-Myc, Lin28; (8) Oct3 / 4, Klf4, Sox2, L-Myc, Lin28, SV40LT; (9) Oct3 / 4, Klf4, Sox2, L-Myc, Lin28, TERT, SV40LT; (10) Oct3 / 4, Klf4, Sox2, L-Myc, SV40LT; (11) Oct3 / 4, Esrrb, Sox2, L-Myc (Esrrb may be replaceable with Esrrg); (12) Oct3 / 4, Klf4, Sox2; (13) Oct3 / 4, Klf4, Sox2, TERT, SV40LT; (14) Oct3 / 4, Klf4, Sox2, TERT, HPV16 E6; (15) Oct3 / 4, Klf4, Sox2, TERT, HPV16 E7; (16) Oct3 / 4, Klf4, Sox2, TERT, HPV16 E6, HPV16 E7; (17) Oct3 / 4, Klf4, Sox2, TERT, Bmil; (18) Oct3 / 4, Klf4, Sox2, Lin28 (19) Oct3 / 4, Klf4, Sox2, Lin28, SV40LT; (20) Oct3 / 4, Klf4, Sox2, Lin28, TERT, SV40LT; (21) Oct3 / 4, Klf4, Sox2, SV40LT; or (22) Oct3 / 4, Esrrb, Sox2 (Esrrb may be replaceable with Esrrg). Factors like Nanog, Lin28, Klf4, or c-Myc can increase reprogramming efficiency and can be expressed from several different expression vectors. For example, an integrating vector such as the EBV element-based system can be used (U. S. Patent No. 8,546,140). Reprogramming proteins could be introduced directly into somatic cells by protein transduction. Reprogramming may further comprise contacting the cells with one or more signaling receptors including glycogen synthase kinase 3 (GSK-3) inhibitor, a mitogen-activated protein kinase kinase (MEK) inhibitor, a transforming growth factor beta (TGF-β) receptor inhibitor or signaling inhibitor, leukemia inhibitory factor (LIF), a p53 inhibitor, an NF-kappa B inhibitor, or a combination thereof. Those regulators may include small molecules, inhibitory nucleotides, expression cassettes, or protein factors.

[0088] Mouse and human cDNA sequences of these nuclear reprogramming substances are available with reference to the NCBI accession numbers mentioned in WO 2007 / 069666, which is incorporated herein by reference. Methods for introducing one or more reprogramming substances, or nucleic acids encoding these reprogramming substances, are known in the art, and disclosed for example, in U. S. Patent No. 8,900,871 and U. S. Patent No. 8,071,369, which both are incorporated herein by reference.

[0089] Once derived, iPSCs can be cultured in a medium sufficient to maintain pluripotency. The iPSCs may be used with various media and techniques developed to culture pluripotent stem cells, more specifically, embryonic stem cells, as described in U. S. Patent No. 7,442,548 and U. S.Attorney Docket No.: 132042-5007-WOPatent Publication No. 2003 / 0211603. Other methods for the culture and maintenance of iPSCs, as would be known to one of skill in the art, may be used.

[0090] In some embodiments, photoreceptor precursor (PRP) cells may be used in the methods disclosed herein. Such PRPs may be obtained from an iPSC. In some embodiments, the composition comprising the PRPs obtained from an iPSC may be termed “induced” PRPs (iPRPs). PRP cells may express one or more markers such as AIPL1, OTX2, CRX, NR2E3, PPP4R4, PRDM1 (BLIMP1), NEUROD1, RCVRN, TUBB3 and LICAM (CD171). PRP cells may express several proteins that can serve as markers for detection by the use of methodologies, such as immunocytochemistry, Western blot analysis, flow cytometry, or enzyme-linked immunoassay (ELISA). For example, one characteristic PRP-marker is RCVRN. PRP cells may not express (at any detectable level) the embryonic stem cells markers OCT-4, NANOG, or REX-1. Specifically, expression of these genes may be approximately 100 to 1,000-fold lower in PRP cells than in iPSC cells when assessed by quantitative RT-PCR.

[0091] PRP cell markers may be detected at the mRNA level, for example, by reverse transcriptase polymerase chain reaction (RT-PCR), Northern blot analysis, or dot-blot hybridization analysis using sequence-specific primers in standard amplification methods using publicly available sequence data (GENBANK®). Expression of tissue-specific markers as detected at the protein or mRNA level may be considered positive if the level is at least about 2-, at least about 3-, at least about 4-, at least about 5-, at least about 6-, at least about 7-, at least about 8-, or at least about 9-fold, and more particularly more than at least about 10, at least about 20-, at least about 30-, at least about 40-, at least about 50-fold or higher above that of a control cell, such as an undifferentiated pluripotent stem cell or other unrelated cell type.

[0092] In some embodiments, the differentiation from iPSCs into photoreceptor precursor cells is performed as described in WO 2019 / 204817 A1, which is herein incorporated by reference in its entirety.

[0093] In some embodiments, the iPSCs are obtained from a working cell bank (WCB). In some embodiments, the WCB cells are thawed, expanded, and differentiated into induced photoreceptor precursor cells (iPRPs). In some embodiments, the iPRPs are formulated into cryopreservation medium (CryoSTOR® CS10 Cell Freezing Medium) and stored in the vapor phase of liquid nitrogen (about < -150°C) as cryopreserved Drug Product (DP). In some embodiments, the cryopreserved DP undergoes a thaw, wash, and final formulation as a dose forAttorney Docket No.: 132042-5007-WOadministration (DfA) with Balanced Salt Solution (BSS®) Sterile Irrigating Solution supplemented with 0.2% Human Serum Albumin (HSA).

[0094] In some embodiments, the cryopreserved WCB iPSCs are thawed and seeded onto vitronectin-coated plates and cultured overnight. In some embodiments, the iPSCs are further cultured for about 1, about 2, about 3, about 4, about 5, or about 6 days with daily medium exchange. In some embodiments, the iPSCs are cultured for about three to about four days with daily medium exchange. In some embodiments, lactate concentration is assessed to monitor cell growth.

[0095] In some embodiments, the cells are passaged with ethylenediaminetetraacetic acid (EDTA), harvested, and seeded into vitronectin-coated flasks. In some embodiments, the iPSCs are cultured for an additional three days with daily medium exchange. In some embodiments, the cells are then passaged using TrypLE™ for aggregate dissociation. In some embodiments, the cells are then pooled, and the single cell suspension is analyzed for viable cell concentration. In some embodiments, the cells are then pooled and seeded into vitronectin-coated vessels and cultured for about two days with daily medium exchange.

[0096] In some embodiments, the cells are then cultured in vitronectin-coated vessels for about 6, about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, about 15, about 16, or about 17 days with daily medium exchange. In some embodiments, the cells are cultured in vitronectin-coated vessels for about 11 days with daily medium exchange. In some embodiments, the cells are cultured in vitronectin-coated vessels for about 15 days with daily medium exchange.

[0097] In some embodiments, cells are then harvested with TrypLE™, centrifuged, resuspended, pooled, and strained to remove large clusters and isolate single cells. In some embodiments, the resulting single cell suspension is assessed for cell viability. In some embodiments, the cells are then seeded into suspension bioreactors for further expansion. In some embodiments, the cells are further cultured in suspension as aggregates for about 28 to about 68 days with daily medium exchange. In some embodiments, the cells are cultured in suspension as aggregates for about 28, about 29, about 30, about 31, about 32, about 33, about 34, about 35, about 36, about 37, about 38, about 39, about 40, about 41, about 42, about 43, about 44, about 45, about 46, about 47, about 48, about 49, about 50, about 51, about 52, about 53, about 54, about 55, about 56, about 57, about 58, about 59, about 60, about 61, about 62, about 63, about 64, about 65, about 66, about 67, or about 68 days with daily medium exchange.Attorney Docket No.: 132042-5007-WOIn some embodiments, the cells are further cultured in suspension as aggregates for about 48 days with daily medium exchange. In some embodiments, DAPT is added. In some embodiments, lactate concentration, pH, dissolved oxygen, cell patterning, and / or karyotypes are monitored.

[0098] In some embodiments, cells are then harvested and triturated into a single cell suspension and strained. In some embodiments, the cells are assessed for viable cell concentration. In some embodiments, the cells are seeded onto laminin 521-coated vessels. In some embodiments, isethionate is added.

[0099] In some embodiments, the cells are then harvested, centrifuged, resuspended, pooled, and strained. In some embodiments, the cells are enriched for CD133+ cells, pooled, and assessed for viable cell concentration. In some embodiments, the culture is further maintained for about 1, about 2, about 3, or about 4 days to generate cell aggregates. In some embodiments, the cells are then pooled and strained, and a drug substance is obtained.

[0100] In some embodiments, the composition comprising the population of PRP cells comprises at least about 10% to at most about 100% NR2E3-expressing cells (e.g., at least about 10%, about 11%, about 12%, about 13%, about 14%, about 15%, about 16%, about 17%, about 18%, about 19%, about 20%, about 21%, about 22%, about 23%, about 24%, about 25%, about 26%, about 27%, about 28%, about 29%, about 30%, about 31%, about 32%, about 33%, about 34%, about 35%, about 36%, about 37%, about 38%, about 39%, about 40%, about 41%, about 42%, about 43%, about 44%, about 45%, about 46%, about 47%, about 48%, about 49%, about 50%, about 51%, about 52%, about 53%, about 54%, about 55%, about 56%, about 57%, about 58%, about 59%, about 60%, about 61%, about 62%, about 63%, about 64%, about 65%, about 66%, about 67%, about 68%, about 69%, about 70%, about 71%, about 72%, about 73%, about 74%, about 75%, about 76%, about 77%, about 78%, about 79%, about 80%, about 81%, about 82%, about 83%, about 84%, about 85%, about 86%, about 87%, about 88%, about 89%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or about 100% NR2E3-expressing cells).

[0101] In some embodiments, the drug product is formulated into a dose for administration by thawing, washing, and diluting with a vehicle solution. In some embodiments, the vehicle solution is Balanced Salt Solution (BSS®) Sterile Irrigating Solution supplemented with 0.2% Human Serum Albumin (HSA). In some embodiments, aggregates are enriched with slow-rate centrifugation. In some embodiments, a live cell concentration and / or percentage viability is assessed for the dose for administration. In some embodiments, the concentration of cells mayAttorney Docket No.: 132042-5007-WObe adjusted by dilution or centrifugation with resuspension. In some embodiments, the dose for administration is further assessed for sterility, endotoxin levels, and / or visual appearance.

[0102] In an aspect, the disclosure provides a composition comprising a population of PRP cells. In some embodiments, at least about 80% of the composition comprising the population of PRP cells expresses RCVRN (e.g., about 80%, about 81%, about 82%, about 83%, about 84%, about 85%, about 86%, about 87%, about 88%, about 89%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95% about 96%, about 97%, about 98% about 99%, or about 100% of the composition comprising the population of PRP cells expresses RCVRN). In particular embodiments, the disclosure provides a composition comprising a population of PRP cells. In some embodiments, about 80% to about 100% (e.g., about 80% to about 100%, about 80% to about 90%, about 90% to about 100%, about 90% to about 99%, about 90% to about 98%, about 90% to about 97%, about 90% to about 96%, about 90% to about 95%, about 90% to about 94%, about 90% to about 93%, about 90% to about 92%, about 90% to about 91%, about 91% to about 100%, about 91% to about 99%, about 91% to about 98%, about 91% to about 97%, about 91% to about 96%, about 91% to about 95%, about 91% to about 94%, about 91% to about 93%, about 91% to about 92%, about 92% to about 100%, about 92% to about 99%, about 92% to about 98%, about 92% to about 97%, about 92% to about 96%, about 92% to about 95%, about 92% to about 94%, about 92% to about 93%, about 93% to about 100%, about 93% to about 99%, about 93% to about 98%, about 93% to about 97%, about 93% to about 96%, about 93% to about 95%, about 93% to about 94%, about 94% to about 100%, about 94% to about 99%, about 94% to about 98%, about 94% to about 97%, about 94% to about 96%, about 94% to about 95%, about 95% to about 100%, about 95% to about 99%, about 95% to about 98%, about 95% to about 97%, about 95% to about 96%, about 96% to about 100%, about 96% to about 99%, about 96% to about 98%, about 96% to about 97%, about 97% to about 100%, about 97% to about 99%, about 97% to about 98%, about 98% to about 100%, about 98% to about 99%, or about 99% to about 100%) of the composition comprising the population of PRP cells expresses Recoverin (RCVRN). In some embodiments, the composition comprising the population of PRP cells comprises at least about 90% of RCVRN expressing cells.

[0103] In some embodiments, at least about 80% of the composition comprising the population of PRP cells expresses AIPL1 (e.g., about 80%, about 81%, about 82%, about 83%, about 84%, about 85%, about 86%, about 87%, about 88%, about 89%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or about 100% of the composition comprising the population of PRP cells expresses AIPL1). In someAttorney Docket No.: 132042-5007-WOembodiments, about 90% to about 100% {e.g., about 90% to about 100%, about 90% to about 99%, about 90% to about 98%, about 90% to about 97%, about 90% to about 96%, about 90% to about 95%, about 90% to about 94%, about 90% to about 93%, about 90% to about 92%, about 90% to about 91%, about 91% to about 100%, about 91% to about 99%, about 91% to about 98%, about 91% to about 97%, about 91% to about 96%, about 91% to about 95%, about 91% to about 94%, about 91% to about 93%, about 91% to about 92%, about 92% to about 100%, about 92% to about 99%, about 92% to about 98%, about 92% to about 97%, about 92% to about 96%, about 92% to about 95%, about 92% to about 94%, about 92% to about 93%, about 93% to about 100%, about 93% to about 99%, about 93% to about 98%, about 93% to about 97%, about 93% to about 96%, about 93% to about 95%, about 93% to about 94%, about 94% to about 100%, about 94% to about 99%, about 94% to about 98%, about 94% to about 97%, about 94% to about 96%, about 94% to about 95%, about 95% to about 100%, about 95% to about 99%, about 95% to about 98%, about 95% to about 97%, about 95% to about 96%, about 96% to about 100%, about 96% to about 99%, about 96% to about 98%, about 96% to about 97%, about 97% to about 100%, about 97% to about 99%, about 97% to about 98%, about 98% to about 100%, about 98% to about 99%, or about 99% to about 100%) of the composition comprising the population of PRP cells expresses aryl-hydrocarbon interacting protein-like 1 (AIPL1). In some embodiments, the composition comprising the population of PRP cells comprises at least about 90% of AIPL1-expressing cells.

[0104] In some embodiments, the composition comprising the population of PRP cells comprises at least about 20% PPP4R4-expressing cells (e.g., at least about 20%, about 21%, at least 22%, about 23%, about 24%, about 25%, about 26%, about 27%, about 28%, about 29%, about 30%, about 31%, about 32%, about 33%, about 34%, about 35%, about 36%, about 37%, about 38%, about 39%, about 40%, about 41%, about 42%, about 43%, about 44%, about 45%, about 46%, about 47%, about 48%, about 49%, about 50%, about 51%, about 52%, about 53%, about 54%, about 55%, about 56%, about 57%, about 58%, about 59%, or about 60% PPP4R4-expressing cells). In some embodiments, the composition comprising the population of PRP cells comprises at most about 60% (e.g., about 20%, about 21%, at least 22%, about 23%, about 24%, about 25%, about 26%, about 27%, about 28%, about 29%, about 30%, about 31%, about 32%, about 33%, about 34%, about 35%, about 36%, about 37%, about 38%, about 39%, about 40%, about 41%, about 42%, about 43%, about 44%, about 45%, about 46%, about 47%, about 48%, about 49%, about 50%, about 51%, about 52%, about 53%, about 54%, about 55%, about 56%, about 57%, about 58%, about 59%, or about 60% PPP4R4-expressing cells). In some embodiments, the composition comprising the population of PRP cells comprises between aboutAttorney Docket No.: 132042-5007-WO20% and about 60% (e.g., about 20% to about 60%, about 20% to about 50%, about 20% to about 40%, about 20% to about 30%, about 30% to about 60%, about 30% to about 50%, about 30% to about 40%, about 40% to about 60%, about 40% to about 50%, or about 50% to about 60%) PPP4R4 expressing cells. In some embodiments, PPP4R4 expressing cells are cone-committed PRPs. In some embodiments, the composition comprising the population of PRP cells comprises at least about 20% PPP4R4-expressing cells. In some embodiments, the composition comprising the population of PRP cells comprises at most about 60% PPP4R4-expressing cells. In some embodiments, the composition comprising the population of PRP cells comprises at least about 20% of PPP4R4-expressing cells and at most about 60% PPP4R4-expressing cells.

[0105] In some embodiments, the composition comprising the population of PRP cells comprises at least about 10% to at most about 100% NR2E3-expressing cells (e.g., at least about 10%, about 11%, about 12%, about 13%, about 14%, about 15%, about 16%, about 17%, about 18%, about 19%, about 20%, about 21%, about 22%, about 23%, about 24%, about 25%, about 26%, about 27%, about 28%, about 29%, about 30%, about 31%, about 32%, about 33%, about 34%, about 35%, about 36%, about 37%, about 38%, about 39%, about 40%, about 41%, about 42%, about 43%, about 44%, about 45%, about 46%, about 47%, about 48%, about 49%, about 50%, about 51%, about 52%, about 53%, about 54%, about 55%, about 56%, about 57%, about 58%, about 59%, about 60%, about 61%, about 62%, about 63%, about 64%, about 65%, about 66%, about 67%, about 68%, about 69%, about 70%, about 71%, about 72%, about 73%, about 74%, about 75%, about 76%, about 77%, about 78%, about 79%, about 80%, about 81%, about 82%, about 83%, about 84%, about 85%, about 86%, about 87%, about 88%, about 89%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or about 100% NR2E3-expressing cells). In some embodiments, the composition comprising the population of PRP cells comprises between about 10% and about 100% (e.g., about 10% to about 100%, about 10% to about 90%, about 10% to about 80%, about 10% to about 70%, about 10% to about 60%, about 10% to about 50%, about 10% to about 40%, about 10% to about 30%, about 10% to about 20%, about 20% to about 100%, about 20% to about 90%, about 20% to about 80%, about 20% to about 70%, about 20% to about 60%, about 20% to about 50%, about 20% to about 40%, about 20% to about 30%, about 30% to about 100%, about 30% to about 80%, about 30% to about 70%, about 30% to about 60%, about 30% to about 50%, about 30% to about 40%, about 40% to about 100%, about 40% to about 90%, about 40% to about 80%, about 40% to about 70%, about 40% to about 60%, about 40% to about 50%, about 50% to about 100%, about 50% to about 90%, about 50% to about 80%, about 50% to about 70%, about 50% to about 60%, about 60% to about 100%, about 60% to about 90%, about 60%Attorney Docket No.: 132042-5007-WOto about 80%, about 60% to about 70%, about 70% to about 100%, about 70% to about 90%, about 70% to about 80%, about 80% to about 100%, about 80% to about 90%, or about 90% to about 100%) NR2E3-expressing cells. In some embodiments, NR2E3 expressing cells are rod-committed PRPs. In some embodiments, the composition comprising the population of PRP cells comprises at least about 25% to at most about 65% NR2E3-expressing cells. In some embodiments, the composition comprising the population of PRP cells comprises at least about 40% to at most about 80% NR2E3-expressing cells.

[0106] In some embodiments, a composition comprising the population of cells comprising 90% PRP cells comprises at least about 90% AIPL1-expressing cells and at least about 90% RCVRN-expressing cells. In further embodiments, of those 90% PRPs expressing AIPL1 and RCVRN, a first portion will express PPP4R4 and a second portion will express NR2E3. In further embodiments, of those 90% PRPs expressing Al PL1 and RCVRN, the first portion will express PPP4R4 but will not express NR2E3. In further embodiments, of those 90% PRPs expressing AIPL1 and RCVRN, the second portion will express NR2E3 but will not express PPP4R4. In further embodiments, of those 90% PRPs expressing AIPL1 and RCVRN, at least about 20% of the cells will express PPP4R4, at least about 80% of the cells will express NR2E3. In further embodiments, of those 90% PRPs expressing AIPL1 and RCVRN, at least about 30% of the cells will express PPP4R4, at least about 70% of the cells will express NR2E3. In further embodiments, of those 90% PRPs expressing AIPL1 and RCVRN, at least about 40% of the cells will express PPP4R4, at least about 60% of the cells will express NR2E3. In further embodiments, of those 90% PRPs expressing AIPL1 and RCVRN, at least about 50% of the cells will express PPP4R4, at least about 50% of the cells will express NR2E3. In further embodiments, of those 90% PRPs expressing AIPL1 and RCVRN, at least about 60% of the cells will express PPP4R4, at least about 40% of the cells will express NR2E3.

[0107] In some embodiments, the composition comprising the population of PRP cells comprises about 0.0 copies to about 0.5 copies VIM per copy of SDHA as measured by ddPCR, (e.g., about 0.0, about 0.05, about 0.10, about 0.15, about 0.20, about 0.25, about 0.30, about 0.35, about 0.40, about 0.45, or about 0.50 copies VIM per copy SDHA as measured by ddPCR). In some embodiments, the composition comprising the population of PRP cells comprises VIM+ cells. In some embodiments, the composition comprising the population of PRP cells comprises between about 0.0 copies and about 0.50 copies (e.g., about 0.0 copies to about 0.1, about 0.0 copies to about 0.2, about 0.0 copies to about 0.3, about 0.0 copies to about 0.4, about 0.0 copies to about 0.5, about 0.1 copies to about 0.2, about 0.1 copies to about 0.3, about 0.1 copies toAttorney Docket No.: 132042-5007-WOabout 0.4, about 0.1 copies to about 0.5, about 0.2 copies to about 0.3, about 0.2 copies to about 0.4, about 0.2 copies to about 0.5, about 0.3 copies to about 0.4, about 0.3 copies to about 0.5, or about 0.4 copies to about 0.5) VIM per copy of a reference gene, e.g., SDHA, as measured by ddPCR. In some embodiments, the composition comprising the population of PRP cells comprises at most 0.5 copies VIM per copy SDHA as measured by ddPCR. In some embodiments, ddPCR is performed using Bio-Rad’s QX200™ ddPCR System. In some embodiments, copies of VIM is determined relative to reference gene SDHA.

[0108] In some embodiments, the composition comprising the population of PRP cells comprises at most 7% PAX6-expressing cells {e.g., about 7.0%, about 6.75%, about 6.50%, about 6.25%, about 6.0%, about 5.75%, about 5.50%, about 5.25%, about 5.0%, about 4.75%, about 4.50%, about 4.25%, about 4.0%, about 3.75%, about 3.50%, about 3.25%, about 3.0%, about 2.75%, about 2.50%, about 2.25%, about 2.0%, about 1.75%, about 1.50%, about 1.25%, about 1.0%, about 0.75%, about 0.50%, about 0.25%, or about 0.0% PAX6-expressing cells). In some embodiments, the composition comprising the population of PRP cells comprises between about 0% and about 7% e.g., about 0% to about 7%, about 0% to about 6%, about 0% to about 5%, about 0% to about 4%, about 0% to about 3%, about 0% to about 2%, about 0% to about 1%, about 1% to about 7%, about 1% to about 6%, about 1% to about 5%, about 1% to about 4%, about 1% to about 3%, about 1% to about 2%, about 2% to about 7%, about 2% to about 6%, about 2% to about 5%, about 2% to about 4%, about 2% to about 3%, about 3% to about 7%, about 3% to about 6%, about 3% to about 5%, about 3% to about 4%, about 4% to about 7%, about 4% to about 6%, about 4% to about 5%, about 5% to about 7%, about 5% to about 6%, or about 6% to about 7%) PAX6--expressing cells. In some embodiments, the composition comprising the population of PRP cells comprises at most about 7% PAX6-expressing cells.

[0109] In some embodiments, the composition comprising the population of PRP cells comprises at most 5% CHX10-expressing cells {e.g., about 7.0%, about 6.75%, about 6.50%, about 6.25%, about 6.0%, about 5.75%, about 5.50%, about 5.25%, about 5.0%, about 4.75%, about 4.50%, about 4.25%, about 4.0%, about 3.75%, about 3.50%, about 3.25%, about 3.0%, about 2.75%, about 2.50%, about 2.25%, about 2.0%, about 1.75%, about 1.50%, about 1.25%, about 1.0%, about 0.75%, about 0.50%, about 0.25%, or about 0.0% CHX10-expressing cells). In some embodiments, the composition comprising the population of PRP cells comprises between about 0% and about 7% {e.g., about 0% to about 7%, about 0% to about 6%, about 0% to about 5%, about 0% to about 4%, about 0% to about 3%, about 0% to about 2%, about 0% to about 1%, about 1% to about 7%, about 1% to about 6%, about 1% to about 5%, about 1% toAttorney Docket No.: 132042-5007-WOabout 4%, about 1% to about 3%, about 1% to about 2%, about 2% to about 7%, about 2% to about 6%, about 2% to about 5%, about 2% to about 4%, about 2% to about 3%, about 3% to about 7%, about 3% to about 6%, about 3% to about 5%, about 3% to about 4%, about 4% to about 7%, about 4% to about 6%, about 4% to about 5%, about 5% to about 7%, about 5% to about 6%, or about 6% to about 7%) CHX10-expressing cells. In some embodiments, the composition comprising the population of PRP cells comprises at most about 7% CHX10-expressing cells.

[0110] In some embodiments, the composition comprising the population of PRP cells comprises at most about 0.5% Ki67-expressing cells (e.g., about 0.00%, about 0.05%, about 0.10%, about 0.15%, about 0.20%, about 0.25%, about 0.30%, about 0.35%, about 0.40%, about 0.45%, or about 0.50% Ki67-expressing cells). In some embodiments, the composition comprising the population of PRP cells comprises between about 0% and about 0.5% (e.g., about 0.0% to about 0.1%, about 0.0% to about 0.2%, about 0.0% to about 0.3%, about 0.0% to about 0.4%, about 0.0% to about 0.5%, about 0.1% to about 0.2%, about 0.1% to about 0.3%, about 0.1% to about 0.4%, about 0.1% to about 0.5%, about 0.2% to about 0.3%, about 0.2% to about 0.4%, about 0.2% to about 0.5%, about 0.3% to about 0.4%, about 0.3% to about 0.5%, or about 0.4% to about 0.5%) Ki67-expressing cells. In some embodiments, the composition comprising the population of PRP cells comprises at most 0.5% Ki67-expressing cells.

[0111] In some embodiments, the composition comprising the population of PRP cells comprises at most 0.5% TYRP1 -expressing cells (e.g., about 0.00%, about 0.05%, about 0.10%, about 0.15%, about 0.20%, about 0.25%, about 0.30%, about 0.35%, about 0.40%, about 0.45%, or about 0.50% TYRP1 -expressing cells. In some embodiments, the composition comprising the population of PRP cells comprises between about 0% and about 0.5% (e.g., about 0.0% to about 0.1%, about 0.0% to about 0.2%, about 0.0% to about 0.3%, about 0.0% to about 0.4%, about 0.0% to about 0.5%, about 0.1% to about 0.2%, about 0.1% to about 0.3%, about 0.1% to about 0.4%, about 0.1% to about 0.5%, about 0.2% to about 0.3%, about 0.2% to about 0.4%, about 0.2% to about 0.5%, about 0.3% to about 0.4%, about 0.3% to about 0.5%, or about 0.4% to about 0.5%) TYRP1- expressing cells. In some embodiments, the composition comprising the population of PRP cells comprises at most 0.5% TYRP1 -expressing cells.

[0112] In some embodiments, the composition comprising the population of PRP cells comprises NR2E3+ cells (e.g., at an amount or percentage described herein), between at least about 20% and at most about 60% PPP4R4+ cells, at most 0.5 copies VIM per copy SDHA, at least about 90% AIPL1+ cells, at least about 90% RCVRN+ cells, at most about 7% PAX6+ cells,Attorney Docket No.: 132042-5007-WOat most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, and / or at most about 0.5% Ki67+ cells. In some embodiments, the composition comprising the population of PRP cells comprises between at least about 20% and at most about 60% PPP4R4+ cells and at most 0.5 copies VIM per copy SDHA. In some embodiments, the composition comprising the population of PRP cells comprises NR2E3+ cells and between at least about 20% and at most about 60% PPP4R4+ cells. In some embodiments, the composition comprising the population of PRP cells comprises NR2E3+ cells, between at least about 20% and at most about 60% PPP4R4+ cells, and at most 0.5 copies VIM per copy SDHA. In some embodiments, the composition comprising the population of PRP cells comprises at least about 90% AIPL1+ cells and at least about 90% RCVRN+ cells. In some embodiments, the composition comprising the population of PRP cells comprises NR2E3+ cells, between at least about 20% and at most about 60% PPP4R4+ cells, at most 0.5 copies VIM per copy SDHA, at least about 90% AIPL1+ cells, and at least about 90% RCVRN+ cells. In some embodiments, the composition comprising the population of PRP cells comprises at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, and / or at most about 0.5% Ki67+ cells. In some embodiments, the composition comprising the population of PRP cells comprises NR2E3+ cells and between at least about 20% to about 60% PPP4R4+ cells.

[0113] Also provided herein is a composition comprising a population of PRP cells (also referred to herein as BRT-A), wherein the composition comprises between about 40% and about 80% NR2E3+ cells, between at least about 20% and at most about 60% PPP4R4+ cells, at most 0.5 copies VIM per copy SDHA, at least about 90% AIPL1+ cells, at least about 90% RCVRN+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1 + cells, and / or at most about 0.5% Ki67+ cells.

[0114] In certain aspects, the composition comprising the population of PRP cells does not express or have substantially no expression of CRALBP, BEST1, IGFBP5, COL8A1, ELN, UPK3B, TPM2, PTGDS, SERPINE3, TIMP3, MITF, and / or PMEL17. In some embodiments, the composition comprising the population of PRP cells has low or substantially no expression of PAX6, CHX10 (also referred to as VSX2), Ki67, TYRP1, and / or ONECUT1. In particular embodiments, at most about 15% (e.g., about 0% to about 15%, about 0% to about 14%, about 0% to about 13%, about 0% to about 12%, about 0% to about 11%, about 0% to about 10%, about 0% to about 9%, about 0% to about 8%, about 0% to about 7%, about 0% to about 6%, about 0% to about 5%, about 0% to about 4%, about 0% to about 3%, about 0% to about 2%, about 0% to about 1%, about 1% to about 15%, about 1% to about 14%, about 1% to about 13%, about 1%Attorney Docket No.: 132042-5007-WOto about 12%, about 1% to about 11%, about 1% to about 10%, about 1% to about 9%, about 1% to about 8%, about 1% to about 7%, about 1% to about 6%, about 1% to about 5%, about 1% to about 4%, about 1% to about 3%, about 1% to about 2%, about 2% to about 15%, about 2% to about 14%, about 2% to about 13%, about 2% to about 12%, about 2% to about 11%, about 2% to about 10%, about 2% to about 9%, about 2% to about 8%, about 2% to about 7%, about 2% to about 6%, about 2% to about 5%, about 2% to about 4%, about 2% to about 3%, about 3% to about 15%, about 3% to about 14%, about 3% to about 13%, about 3% to about 12%, about 3% to about 11%, about 3% to about 10%, about 3% to about 9%, about 3% to about 8%, about 3% to about 7%, about 3% to about 6%, about 3% to about 5%, about 3% to about 4%, about 4% to about 15%, about 4% to about 14%, about 4% to about 13%, about 4% to about 12%, about 4% to about 11%, about 4% to about 10%, about 4% to about 9%, about 4% to about 8%, about 4% to about 7%, about 4% to about 6%, about 4% to about 5%, about 5% to about 15%, about 5% to about 14%, about 5% to about 13%, about 5% to about 12%, about 5% to about 11%, about 5% to about 10%, about 5% to about 9%, about 5% to about 8%, about 5% to about 7%, about 5% to about 6%, about 6% to about 15%, about 6% to about 14%, about 6% to about 13%, about 6% to about 12%, about 6% to about 11%, about 6% to about 10%, about 6% to about 9%, about 6% to about 8%, about 6% to about 7%, about 7% to about 15%, about 7% to about 14%, about 7% to about 13%, about 7% to about 12%, about 7% to about 11%, about 7% to about 10%, about 7% to about 9%, about 7% to about 8%, about 8% to about 15%, about 8% to about 14%, about 8% to about 13%, about 8% to about 12%, about 8% to about 11%, about 8% to about 10%, about 8% to about 9%, about 9% to about 15%, about 9% to about 14%, about 9% to about 13%, about 9% to about 12%, about 9% to about 11%, about 9% to about 10%, about 10% to about 15%, about 10% to about 14%, about 10% to about 13%, about 10% to about 12%, about 10% to about 11%, about 11% to about 15%, about 11% to about 14%, about 11% to about 13%, about 11% to about 12%, about 12% to about 15%, about 12% to about 14%, about 12% to about 13%, about 13% to about 15%, about 13% to about 14%, or about 14% to about 15%) of the composition comprising the population of PRP cells express PAX6. In some embodiments, the composition comprising the population of PRP cells comprises at most about 10% or about 5% PAX6-positive cells. In certain embodiments, the composition comprising the population of PRP cells comprises at most about 7% PAX6-positive cells, at most about 0.05% Ki67-positive cells, at most about 30%, about 31%, about 32%, about 33%, about 34%, about 35%, about 36%, about 37%, about 38%, about 39%, about 40%, about 45%, about 50%, about 55%, about 60%, about 70%, about 80%, about 90%, about 95%, or about 100% CHX10-positive cells, and / or at most about 2% ONECUTI-positive cells. In some aspects, the composition comprising the population of PRPAttorney Docket No.: 132042-5007-WOcells comprises at most about 7% PAX6-positive cells, at most about 0.5% Ki67-positive cells, at most about 7% CHX10-positive cells, and / or at most about 1% ONECUTI-positive cells. In certain aspects, the composition comprising the population of PRP cells comprises at most about 7% PAX6-positive cells, at most about 0.5% Ki67-positive cells, at most about 7% CHX10-positive cells, and at most about 1% ONECUTI-positive cells.

[0115] In some embodiments, at least about 90% of the composition comprising the population of PRPs expresses TUBB3 (e.g., 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or about 100% of the composition comprising the population of PRP cells expresses TUBB3). In some embodiments, at least about 90% to about 100% (e.g., about 90% to about 100%, about 90% to about 99%, about 90% to about 98%, about 90% to about 97%, about 90% to about 96%, about 90% to about 95%, about 90% to about 94%, about 90% to about 93%, about 90% to about 92%, about 90% to about 91 %, about 91% to about 100%, about 91% to about 99%, about 91% to about 98%, about 91% to about 97%, about 91% to about 96%, about 91% to about 95%, about 91% to about 94%, about 91% to about 93%, about 91% to about 92%, about 92% to about 100%, about 92% to about 99%, about 92% to about 98%, about 92% to about 97%, about 92% to about 96%, about 92% to about 95%, about 92% to about 94%, about 92% to about 93%, about 93% to about 100%, about 93% to about 99%, about 93% to about 98%, about 93% to about 97%, about 93% to about 96%, about 93% to about 95%, about 93% to about 94%, about 94% to about 100%, about 94% to about 99%, about 94% to about 98%, about 94% to about 97%, about 94% to about 96%, about 94% to about 95%, about 95% to about 100%, about 95% to about 99%, about 95% to about 98%, about 95% to about 97%, about 95% to about 96%, about 96% to about 100%, about 96% to about 99%, about 96% to about 98%, about 96% to about 97%, about 97% to about 100%, about 97% to about 99%, about 97% to about 98%, about 98% to about 100%, about 98% to about 99%, or about 99% to about 100%) of the composition comprising the population of PRP cells expresses Class III β-tubulin (TUBB3). In some embodiments, the composition comprising the population of PRP cells expresses one or more markers selected from the group consisting of: AIPL1, NR2E3, PPP4R4, OTX2, CRX, BLIMP 1, NEUROD1, RCVRN, TUBB3 and CD171 / L1CAM.

[0116] In particular embodiments, the composition comprising the population of PRP cells comprises at least about 70% cell aggregate biomass (e.g., about 70%, about 71%, about 72%, about 73%, about 74%, about 75%, about 76%, about 77%, about 78%, about 79%, about 80%, about 81%, about 82%, about 83%, about 84%, about 85%, about 86%, about 87%, about 88%,Attorney Docket No.: 132042-5007-WOabout 89%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or about 100% cell aggregate biomass). In some embodiments, the composition comprising the population of PRP cells comprises between about 70% and about 100% (e.g., about 70% to about 100%, about 70% to about 90%, about 70% to about 80%, about 80% to about 100%, about 80% to about 90%, or about 90% to about 100%) cell aggregate biomass. In some embodiments, the composition comprising the population of PRP cells comprises at least about 70% cell aggregate biomass.

[0117] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of, one or more, two or more, three or more, four or more, five or more, six or more, seven or more, eight or more, nine or more, ten or more, eleven or more, or twelve of the characteristics provided in Table 1.Table 1. Specifications for Drug Products Comprising a Composition of Cells Comprising PRPs as Disclosed HereinSpecification CharacteristicAIPL1+ At least 90%RCVRN+ At least 90%PPP4R4+ At least 20% and at most 60%NR2E3+ DetectablePAX6+ At most 7%CHX10+ At most 7%TYRP1+ At most 0.5%Ki67+ At most 0.5%Copies of VIM per copy of SDHA At most 0.5 copies / copyAggregate biomass At least 70%Percentage Viability At least 50%LNCPRESS2 and AC009446.1 Not detectable

[0118] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% AIPL1+ cells, at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability ofAttorney Docket No.: 132042-5007-WOat least 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% AIPL1+ cells, at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% AIPL1+ cells, at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% AIPL1+ cells, at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% AIPL1+ cells, at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% AIPL1+ cells, at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% AIPL1+ cells, at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of atAttorney Docket No.: 132042-5007-WOleast 90% AIPL1+ cells, at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% AIPL1+ cells, at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% AIPL1+ cells, at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% AIPL1+ cells, at least 90% RCVRN+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% AIPL1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0119] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition ofAttorney Docket No.: 132042-5007-WOcells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% RCVRN+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0120] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells,Attorney Docket No.: 132042-5007-WOat most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 90% AIPL1+ cells, at least 90% RCVRN+ cells, at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, at most 7% PAX6+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pelletAttorney Docket No.: 132042-5007-WOform. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 20% and at most 60% PPP4R4+ cells, NR2E3+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 20% and at most 60% PPP4R4+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0121] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consistsAttorney Docket No.: 132042-5007-WOessentially of NR2E3+ cells, at most 7% PAX6+ cells, at most 7% CHX10+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most 7% PAX6+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0122] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 7% PAX6+ cells, at most 7% CHX10+ cells, at most 0.5% TYRP1 + cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPsAttorney Docket No.: 132042-5007-WOas disclosed herein, comprises, or consists of, or consists essentially of at most 7% PAX6+ cells, at most 7% CHX10+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 7% PAX6+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0123] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 7% CHX10+ cells, at most 0.5% TYRP1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 7% CHX10+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.Attorney Docket No.: 132042-5007-WO

[0124] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5% TYRP1+ cells, at most 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5% TYRP1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0125] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregateAttorney Docket No.: 132042-5007-WObiomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5% Ki67+ cells, at most 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0126] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, a percentage viability of at least 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5 copies of VIM per copy of SDHA, at least 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0127] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 70% aggregate biomass, a percentage viability of at least 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 70% aggregate biomass, a percentage viability of at least 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.Attorney Docket No.: 132042-5007-WO

[0128] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of a percentage viability of at least 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of a percentage viability of at least 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0129] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0130] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% AIPL1+ cells, at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1 + cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% AIPL1+ cells, at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% AIPL1 + cells, at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of atAttorney Docket No.: 132042-5007-WOleast about 90% AIPL1+ cells, at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% AIPL1+ cells, at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% AIPL1+ cells, at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% AIPL1+ cells, at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% AIPL1 + cells, at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% AIPL1+ cells, at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% Al PL1 + cells, at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% AIPL1 + cells, at least about 90% RCVRN+ cells, and wherein the composition is mostly in aggregate form,Attorney Docket No.: 132042-5007-WOwhich is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% AIPL1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0131] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1 + cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In someAttorney Docket No.: 132042-5007-WOembodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% RCVRN+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0132] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1 + cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA,Attorney Docket No.: 132042-5007-WOat least about 70% aggregate biomass, a percentage viability of at least about 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1 + cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 90% AIPL1 + cells, at least about 90% RCVRN+ cells, at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, at most about 7% PAX6+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 20% and at most about 60% PPP4R4+ cells, NR2E3+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consistsAttorney Docket No.: 132042-5007-WOof, or consists essentially of at least about 20% and at most about 60% PPP4R4+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0133] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. InAttorney Docket No.: 132042-5007-WOsome embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, at most about 7% PAX6+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of NR2E3+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0134] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition ofAttorney Docket No.: 132042-5007-WOcells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% PAX6+ cells, at most about 7% CHX10+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% PAX6+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0135] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% CHX10+ cells, at most about 0.5% TYRP1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 7% CHX10+ cells, and wherein theAttorney Docket No.: 132042-5007-WOcomposition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0136] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5% TYRP1 + cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5% TYRP1 + cells, at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5% TYRP1+ cells, at most about 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5% TYRP1+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0137] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5% Ki67+ cells, at most aboutAttorney Docket No.: 132042-5007-WO0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5% Ki67+ cells, at most about 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5% Ki67+ cells, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0138] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, a percentage viability of at least about 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5 copies of VIM per copy of SDHA, at least about 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at most about 0.5 copies of VIM per copy of SDHA, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.Attorney Docket No.: 132042-5007-WO

[0139] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 70% aggregate biomass, a percentage viability of at least about 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 70% aggregate biomass, a percentage viability of at least about 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 70% aggregate biomass, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0140] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of a percentage viability of at least about 50%, no detectable expression of LNCPRESS2 and / or AC009446.1, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of a percentage viability of at least about 50%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0141] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of, one or more, two or more, or three or more of the characteristics provided in Table 2.Table 2. Specifications for Doses for Administration Comprising a Composition of Cells Comprising PRPs as Disclosed HereinSpecification Characteristic1 X106dose - Live Cell Concentration At least 2.72x107and at most 4.08x1072x106dose - Live Cell Concentration At least 5.04x107and at most 7.56x1073x106dose - Live Cell Concentration At least 7.12x107and at most 1.07x1084x106dose - Live Cell Concentration At least 9.44x107and at most 1.42x108Endotoxin contamination levels At most 5.0 EU / mLPercentage Viability At least 40%Attorney Docket No.: 132042-5007-WO

[0142] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 2.72x107cells / mL and at most 4.08x107cells / mL, an endotoxin level that is at most 5.0 EU / mL, a percentage viability of at least 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 2.72x107cells / mL and at most 4.08x107cells / mL, a percentage viability of at least 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 2.72x107cells / mL and at most 4.08x107cells / mL, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0143] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 5.04x107cells / mL and at most 7.56x107cells / mL, an endotoxin level that is at most 5.0 EU / mL, a percentage viability of at least 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 5.04x107cells / mL and at most 7.56x107cells / mL, a percentage viability of at least 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 5.04x107cells / mL and at most 7.56x107cells / mL, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0144] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 7.12x107cells / mL and at most 1.07x108cells / mL, an endotoxin level that is at most 5.0 EU / mL, a percentage viability of at least 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 7.12x107cells / mL and at most 1.07x108cells / mL, a percentage viability of at least 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 7.12x107cells / mL and at most 1.07x108cells / mL, an endotoxin level that is at most 5.0Attorney Docket No.: 132042-5007-WOEU / mL, wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0145] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 9.44x107cells / mL and at most 1.42X108cells / mL, an endotoxin level that is at most 5.0 EU / mL, a percentage viability of at least 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 9.44x107cells / mL and at most 1.42X108cells / mL, a percentage viability of at least 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least 9.44x107cells / mL and at most 1.42x108cells / mL, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0146] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 2.72x107cells / mL and at most about 4.08x107cells / mL, an endotoxin level that is at most about 5.0 EU / mL, a percentage viability of at least about 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 2.72X107cells / mL and at most about 4.08x107cells / mL, a percentage viability of at least about 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 2.72x107cells / mL and at most about 4.08x107cells / mL, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0147] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 5.04x107cells / mL and at most about 7.56x107cells / mL, an endotoxin level that is at most about 5.0 EU / mL, a percentage viability of at least about 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 5.04X107cells / mL and at most about 7.56x107cells / mL, a percentage viability of at least about 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. InAttorney Docket No.: 132042-5007-WOsome embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 5.04x107cells / mL and at most about 7.56x107cells / mL, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0148] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 7.12x107cells / mL and at most about 1.07x108cells / mL, an endotoxin level that is at most about 5.0 EU / mL, a percentage viability of at least about 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 7.12x107cells / mL and at most about 1.07x108cells / mL, a percentage viability of at least about 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 7.12x107cells / mL and at most about 1.07x108cells / mL, an endotoxin level that is at most about 5.0 EU / mL, wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0149] In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 9.44x107cells / mL and at most about 1.42x108cells / mL, an endotoxin level that is at most about 5.0 EU / mL, a percentage viability of at least about 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 9.44x107cells / mL and at most about 1.42x108cells / mL, a percentage viability of at least about 40%, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form. In some embodiments, a composition of cells comprising PRPs as disclosed herein, comprises, or consists of, or consists essentially of at least about 9.44x107cells / mL and at most about 1.42x108cells / mL, and wherein the composition is mostly in aggregate form, which is in suspension or pellet form.

[0150] In some embodiments, the median diameter of a cell aggregate is about 15 pm to about 120 pm, (e.g., about 15 pm, about 16 pm, about 17 pm, about 18 pm, about 19 pm, about 20 pm, about 21 pm, about 22 pm, about 23 pm, about 24 pm, about 25 pm, about 26 pm, about 27 pm, about 28 pm, about 29 pm, about 30 pm, about 31 pm, about 32 pm, about 33 pm, about 34 pm, about 35 pm, about 36 pm, about 37 pm, about 38 pm, about 39 pm, about 40 pm, about 41 pm,Attorney Docket No.: 132042-5007-WOabout 42 pm, about 43 pm, about 44 pm, about 45 pm, about 46 pm, about 47 pm, about 48 pm, about 49 pm, about 50 pm, about 51 pm, about 52 pm, about 53 pm, about 54 pm, about 55 pm, about 55 pm, about 56 pm, about 57 pm, about 58 pm, about 59 pm, about 60 pm, about 61 pm, about 62 pm, about 63 pm, about 64 pm, about 65 pm, about 66 pm, about 67 pm, about 68 pm, about 69 pm, about 70 pm, about 71 pm, about 72 pm, about 73 pm, about 74 pm, about 75 pm, about 76 pm, about 77 pm, about 78 pm, about 79 pm, about 80 pm, about 81 pm, about 82 pm, about 83 pm, about 84 pm, about 85 pm, about 86 pm, about 87 pm, about 88 pm, about 89 pm, about 90 pm, about 91 pm, about 92 pm, about 93 pm, about 94 pm, about 95 pm, about 96 pm, about 97 pm, about 98 pm, about 99 pm, about 100 pm, about 101 pm, about 102 pm, about 103 pm, about 104 pm, about 105 pm, about 106 pm, about 107 pm, about 108 pm, about 109 pm, about 110 pm, about 111 pm, about 112 pm, about 113 pm, about 114 pm, about 115 pm, about 116 pm, about 117 pm, about 118 pm, about 119 pm, or about 120 pm). In some embodiments, the median diameter (e.g., particle diameter) of a cell aggregate is between about 15 pm and about 120 pm (e.g., about 15 pm to about 120 pm, about 20 pm to about 115 pm, about 35 pm to about 110 pm, about 35 pm to about 105 pm, about 40 pm to about 100 pm, about 45 pm to about 95 pm, about 50 pm to about 90 pm, about 55 pm to about 85 pm, about 60 pm to about 80 pm, about 65 pm to about 75 pm, about 30 pm to about 60 pm, about 40 pm to about 50 pm, about 20 pm to about 60 pm, about 20 pm to about 50 pm, or about 30 pm to about 60 pm). In some embodiments, the median diameter of a cell aggregate is between about 30 pm and about 60 pm. In some embodiments, the median diameter of a cell aggregate is about 50 pm. In some embodiments, the median diameter of a cell aggregate is at least about 20 pm.

[0151] In some embodiments, the composition comprising the population of PRP cells does not express LNCPRESS2 and / or AC009446.1 pluripotency markers above the limit of detection (LOD). Methods for detecting, characterizing, and / or quantitating, nucleic acid sequences; and for detecting, characterizing, and / or quantitating, mRNA expression, are known to persons skilled in the art, and include, but are not limited to, for example, PCR procedures, RT-PCR, quantitative PCR or RT-PCR, Northern blot analysis, differential gene expression, RNA protection assay, microarray analysis, hybridization methods, serial analysis of gene expression (SAGE), hybridization based on digital barcode quantification assays, multiplex RT-PCR, ddPCR, qRT-PCR, qPCR, UV spectroscopy, DNA sequencing, RNA sequencing, next-generation sequencing, including RNA-seq, lysate-based hybridization assays utilizing branched DNA signal amplification, such as the QuantiGene 2.0 Single Plex, and branched DNA analysis methods. In some embodiments, the composition comprising the population of PRP cells does not expressAttorney Docket No.: 132042-5007-WOLNCPRESS2 and / or AC009446.1 pluripotency markers above the limit of detection as measured by droplet digital polymerase chain reaction (ddPCR).

[0152] In some embodiments, ddPCR is performed using Bio-Rad’s QX200™ ddPCR System. In some embodiments, the LOD is determined against a reference gene, e.g., SDHA. In some embodiments, the number of copies of VIM is determined relative to copies of a reference gene, e.g., SDHA.

[0153] In some embodiments, expression of SDHA, VIM, LNCPRESS2, and / or AC009446.1 was assessed by droplet digital PCR (ddPCR) for cDNA derived from a composition comprising the population of PRP cells. In some embodiments, sample cDNA is diluted and prepared in a PCR master mix. In some embodiments, the master mix containing diluted sample cDNA may be transferred to a 96-well plate. In some embodiments, the plate may be sealed with a ddPCR PX1 PCR Plate Sealer (Bio-Rad, Hercules, CA; Cat. No. 1814000). In some embodiments, droplets may be generated using a QX200™ Automated Droplet Generator (Bio-Rad, Hercules, CA; Cat. No. 1864101). In some embodiments, PCR may be performed to produce amplified droplets using a C1000 Touch™ Thermal Cycler (Bio-Rad, Hercules, CA; Cat. No. 1851148). In some embodiments, the amplified droplets may be assessed using a QX200™ Droplet Reader (BioRad, Hercules, CA; Cat. No. 1864003) to assess VIM, LNCPRESS2, and / or AC009446.1 in channel 1 and SDHA (reference gene) in channel 2 with FAM / VIC probes. In some embodiments, copies per pL of VIM, LNCPRESS2, and / or AC009446.1 divided by copies per pL of SDHA may be reported as a ratio (copies / copy).

[0154] In some embodiments, acceptable samples contain at least 10,000 droplets. In some embodiments, acceptable samples contain a percentage coefficient of variation of less than or equal to 25%. In some embodiments, the cDNA derived from a composition comprising the population of PRP cells may contain between about 800 to about 4,000 SDHA copies per pL. In some embodiments, a cell product suitable for downstream applications will contain no more 0.50 copies / copy of VIM per SDHA (copies per pL of VIM divided by copies per pL of SDHA). In some embodiments, outliers may be assessed and removed, if appropriate, with a Dixon Q Test.

[0155] In some embodiments, a dose for administration comprising PRPs comprises a suspension of at least about 70% to about 100% (e.g., about 70% to about 100%, about 70% to about 90%, about 70% to about 80%, about 80% to about 100%, about 80% to about 90%, or about 90% to about 100%) induced PRP cells (iPRP). In some embodiments, a dose for administration comprising PRPs comprises a suspension of at least about 70%, at least aboutAttorney Docket No.: 132042-5007-WO80%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or about 100% induced PRP cells (iPRP). In some embodiments, the dose for administration may be suspended in a balanced salt solution (BSS) buffer supplemented with human serum albumin (HSA) (e.g., 0.2% HSA). In some embodiments, the dose for administration is in a single cell form, an aggregate form, or in a suspended form. In some embodiments, the dose for administration is in a suspended form. In some embodiments, the dose for administration is in a single cell form or an aggregate form. In some embodiments, the dose for administration is in a pellet formed by centrifugation of a suspension of the drug product. In some embodiments, the drug product comprises aggregates in suspension. In some embodiments, the drug product comprises aggregates in pellet form. In some embodiments, the drug product comprises aggregates that have settled to the bottom of a tube or vial. In some embodiments, the drug product comprises aggregates and single cells in suspension. In some embodiments, the drug product comprises aggregates and single cells in pellet form. In some embodiments, the drug product comprises aggregates and single cells that have settled to the bottom of a tube or vial.

[0156] In some embodiments, a percentage cell viability of a dose for administration comprising PRP cells in a suspended (e.g., single cell suspension) form may be calculated using automated cell counting including, for example, with acridine orange and / or propidium iodide using, for example, a Cellaca™ MX. In some embodiments, the percentage viability of the dose for administration comprising PRP cells in a suspended form may be calculated to be at least about 40% (e.g., about 40%, at least about 41%, at least about 42%, at least about 43%, at least about 44%, at least about 45%, at least about 46%, at least about 47%, at least about 48%, at least about 49%, at least about 50%, at least about 51%, at least about 52%, at least about 53%, at least about 54%, at least about 55%, at least about 56%, at least about 57%, at least about 58%, at least about 59%, at least about 60%, at least about 61%, at least about 62%, at least about 63%, at least about 64%, at least about 65%, at least about 66%, at least about 67%, at least about 68%, at least about 69%, at least about 70%, at least about 71%, at least about 72%, at least about 73%, at least about 74%, at least about 75%, at least about 76%, at least about 77%, at least about 78%, at least about 79%, at least about 80%, at least about 81%, at least about 82%, at least about 83%, at least about 84%, at least about 85%, at least about 86%, at least about 87%, at least about 88%, at least about 89%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or at least about 100%). In some embodiments, the percentage viability of the dose for administration comprising PRP cells in aAttorney Docket No.: 132042-5007-WOsuspended form may be calculated to be at least about 40% to at least about 100% (e.g., about 40% to about 100%, about 40% to about 90%, about 40% to about 80%, about 40% to about 70%, about 40% to about 60%, about 40% to about 50%, about 50% to about 100%, about 50% to about 90%, about 50% to about 80%, about 50% to about 70%, about 50% to about 60%, about 60% to about 100%, about 60% to about 90%, about 60% to about 80%, about 60% to about 70%, about 70% to about 100%, about 70% to about 90%, about 70% to about 80%, about 80% to about 100%, about 80% to about 90%, or about 90% to about 100%). In some embodiments, the percentage viability of the dose for administration comprising PRP cells in a suspended form may be calculated to be at least about 40%.

[0157] In some embodiments, a percentage cell viability of a dose for administration comprising PRP cells in a suspended form may be calculated using automated cell counting including, for example, with an IncuCyte® Live-Cell Analysis System (Sartorius; Gottingen, Germany; Cat. No. SX5). In some embodiments, the percentage viability of the dose for administration comprising PRP cells in a suspended form may be calculated to be at least about 40% (e.g., about 40%, at least about 41 %, at least about 42%, at least about 43%, at least about 44%, at least about 45%, at least about 46%, at least about 47%, at least about 48%, at least about 49%, at least about 50%, at least about 51%, at least about 52%, at least about 53%, at least about 54%, at least about 55%, at least about 56%, at least about 57%, at least about 58%, at least about 59%, at least about 60%, at least about 61 %, at least about 62%, at least about 63%, at least about 64%, at least about 65%, at least about 66%, at least about 67%, at least about 68%, at least about 69%, at least about 70%, at least about 71%, at least about 72%, at least about 73%, at least about 74%, at least about 75%, at least about 76%, at least about 77%, at least about 78%, at least about 79%, at least about 80%, at least about 81%, at least about 82%, at least about 83%, at least about 84%, at least about 85%, at least about 86%, at least about 87%, at least about 88%, at least about 89%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or at least about 100%). In some embodiments, the percentage viability of the dose for administration comprising PRP cells in a suspended form may be calculated to be at least about 40% to at least about 100% (e.g., about 40% to about 100%, about 40% to about 90%, about 40% to about 80%, about 40% to about 70%, about 40% to about 60%, about 40% to about 50%, about 50% to about 100%, about 50% to about 90%, about 50% to about 80%, about 50% to about 70%, about 50% to about 60%, about 60% to about 100%, about 60% to about 90%, about 60% to about 80%, about 60% to about 70%, about 70% to about 100%, about 70% to about 90%, about 70% to about 80%, about 80% to about 100%, about 80%Attorney Docket No.: 132042-5007-WOto about 90%, or about 90% to about 100%). In some embodiments, the percentage viability of the dose for administration comprising PRP cells in a suspended form may be calculated to be at least about 40%.

[0158] In some embodiments, the percentage viability of the dose for administration comprising PRP cells in a single cell form or an aggregate form may be calculated to be at least about 40% (e.g., about 40%, at least about 41%, at least about 42%, at least about 43%, at least about 44%, at least about 45%, at least about 46%, at least about 47%, at least about 48%, at least about 49%, at least about 50%, at least about 51%, at least about 52%, at least about 53%, at least about 54%, at least about 55%, at least about 56%, at least about 57%, at least about 58%, at least about 59%, at least about 60%, at least about 61 %, at least about 62%, at least about 63%, at least about 64%, at least about 65%, at least about 66%, at least about 67%, at least about 68%, at least about 69%, at least about 70%, at least about 71%, at least about 72%, at least about 73%, at least about 74%, at least about 75%, at least about 76%, at least about 77%, at least about 78%, at least about 79%, at least about 80%, at least about 81 %, at least about 82%, at least about 83%, at least about 84%, at least about 85%, at least about 86%, at least about 87%, at least about 88%, at least about 89%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or at least about 100%). In some embodiments, a percentage cell viability of a dose for administration comprising PRP cells in a single cell form or an aggregate form may be calculated using automated cell counting including, for example, with an IncuCyte® Live-Cell Analysis System (Sartorius; Gottingen, Germany; Cat. No. SX5). In some embodiments, the percentage viability of the dose for administration comprising PRP cells in a single cell form or an aggregate form may be calculated to be at least about 40% to at least about 100% (e.g., about 40% to about 100%, about 40% to about 90%, about 40% to about 80%, about 40% to about 70%, about 40% to about 60%, about 40% to about 50%, about 50% to about 100%, about 50% to about 90%, about 50% to about 80%, about 50% to about 70%, about 50% to about 60%, about 60% to about 100%, about 60% to about 90%, about 60% to about 80%, about 60% to about 70%, about 70% to about 100%, about 70% to about 90%, about 70% to about 80%, about 80% to about 100%, about 80% to about 90%, or about 90% to about 100%). In some embodiments, the percentage viability of the dose for administration comprising PRP cells in a single cell form or an aggregate form may be calculated to be at least about 40%.Attorney Docket No.: 132042-5007-WOMethods of Treating an Inherited Retinal Disease

[0159] The disclosure provides a method of treating an inherited retinal disease (I RD; e.g., a primary photoreceptor disease such as retinitis pigmentosa, Usher Syndrome, cone-rod disease, rod-cone disease, cone dystrophy, cone-rod dystrophy, and achromatopsia) in an individual in need thereof. Such methods may comprise administering a composition (e.g., as described herein) comprising photoreceptor precursor cells to said individual. Also provided is a composition comprising photoreceptor cells, e.g., as described herein, for use as a medicament, or for use in a method of treating inherited retinal disease (e.g., a primary photoreceptor disease such as retinitis pigmentosa, Usher Syndrome, cone-rod disease, rod-cone disease, cone dystrophy, and cone-rod dystrophy). The composition may be administered surgically or as a surgical injection to the eye, and / or subretinal space of the eye.

[0160] In certain embodiments, methods are provided for treating a disease or disorder characterized by retinal degeneration (e.g., an I RD), comprising administering to a subject in need thereof an effective amount of a composition comprising PRP cells (e.g., a composition as described herein). These methods may include selecting a subject with such a disease or disorder and administering a therapeutically effective amount of the composition comprising PRP cells sufficient to treat the condition and / or ameliorate symptoms of the condition.

[0161] The disease or disorder may be an inherited retinal disease (IRD). IRDs may include, but are not limited to retinitis pigmentosa, Usher Syndrome, cone-rod disease, rod-cone disease, cone dystrophy, cone-rod dystrophy, and achromatopsia. In some embodiments, the IRD is syndromic. In some embodiments, the IRD may display variable expressivity or variable penetrance among individuals with the same genotype.

[0162] The disease or disorder may be retinitis pigmentosa. Retinitis pigmentosa is an IRD characterized by, e.g., initial loss of night vision and loss of peripheral vision leading to tunnel vision, legal blindness, and often, complete blindness. Retinitis pigmentosa can be syndromic or non-syndromic. In syndromic forms, visual dysfunction may be accompanied by impairment in other organ systems (e.g. obesity and cognitive impairment in Bardet-Biedl syndrome or hearing loss in Usher syndrome). Non-syndromic retinitis pigmentosa primarily affects the retina without affecting other organs.

[0163] The disease or disorder may be cone-rod dystrophy. Cone-rod dystrophy is an IRD that may be characterized by, e.g., loss of visual acuity, increased sensitivity to light (e.g., photophobia), impaired color vision, blind spots (e.g., scotoma), peripheral vision loss, nightAttorney Docket No.: 132042-5007-WOblindness, legal blindness, and often, complete blindness. Cone-rod dystrophy is generally characterized by, e.g., the primary degeneration of cone photoreceptors followed by rod photoreceptors in the retina. Cone-rod dystrophy may be distinguished from cone dystrophy by the early involvement of rod photoreceptors. Symptoms in cone-rod dystrophy may resemble those of cone dystrophy, but patients may also experience night blindness owing to rod dysfunction.

[0164] In some embodiments, the IRD is non-syndromic. In some embodiments, the non-syndromic IRD is of the cone-dominant phenotype. In some embodiments, the non-syndromic IRD is cone dystrophy or cone-rod dystrophy. Cone dystrophies may be defined by a generalized cone dystrophy affecting both macular and peripheral cones, and a characteristic decrease in cone responses at full field electroretinogram (ERG). Patients with cone-dystrophy may present with poor visual acuity and severe color vision disturbances.

[0165] In some embodiments, the non-syndromic IRD is of the rod-dominant phenotype. In some embodiments, the primary pathology of non-syndromic rod-cone diseases may be observed in rod photoreceptor cells. In some embodiments, the rod-dominated disease is retinitis pigmentosa. In some embodiments, the rod-dominated disease is not retinitis pigmentosa. Roddominant IRDs may be characterized by loss of night vision (e.g., nyctalopia) and gradual loss of peripheral vision (e.g., tunnel vision), followed by loss of central vision. In some embodiments, rod-dominant IRDs may lead to legal blindness and often, complete blindness.

[0166] In some embodiments, a composition, for example, as described herein, (e.g., a pharmaceutical composition or drug product) is provided that comprises at least about 104, about 105, about 106, or about 107cells (or any range derivable therein) comprising at least about 50% (for example, at least about 50%, about 60%, about 70%, about 80%, about 85%, about 90%, about 95%, about 96%, about 97%, about 98%, about 99%, about 99.5%, or any range derivable therein) PRP cells.

[0167] In some embodiments, a composition (e.g., an administered dose) is provided that comprises at least about 1x106, about 2x106, about 3x106, about 4x106, or about 5x106cells (or any range derivable therein) comprising at least about 50% (for example, at least about 50%, about 60%, about 70%, about 80%, about 85%, about 90%, about 95%, about 96%, about 97%, about 98%, about 99%, about 99.5%, or any range derivable therein) PRP cells.

[0168] The therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of about 0.5x106to about 5x106cellsAttorney Docket No.: 132042-5007-WO(e.g., viable cells) optionally with an immunosuppressive agent and / or antibiotic. For example, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of about 0.5x10scells, about 0.75x10® cells, about 1.0x10scells, about 1.25x10® cells, about 1.5x10scells, about 1.75x10scells, about 2.0x106cells, about 2.25x10scells, about 2.5x10® cells, about 2.75x10® cells, about 3.0x10scells, about 3.25x10scells, about 3.5x106cells, about 3.75x10scells, about 4.0x10scells, about 4.25x10® cells, about 4.5x10scells, about 4.75x10scells, or about 5.0x106cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of about 0.5x10scells to about 1.0x10® cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of about 1.0x10scells to about 1.5x106cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of about 1.5x10® cells to about 2.0x10® cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of about 2.0x10® cells to about 2.5x10scells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of about 2.5x106cells to about 3.0x106cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of about 3.0x10® cells to about 3.5x10® cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of about 3.5x106cells to about 4.0x106cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of about 4.0x10scells to about 4.5x10® cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of about 4.5x10® cells to about 5.0x10® cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of about 0.5x106cells, about 0.75x10scells, about 1 Ox 10scells, about 1.25x106cells, about 1.5x10® cells, about 1.75x10scells, about 2.0x10scells, about 2.25x106cells, about 2.5x10scells, about 2.75x106cells, about 3.0x106cells, about 3.25x106cells, about 3.5x106cells, about 3.75x106cells, about 4.0x10® cells, about 4.25x10® cells, about 4.5x106cells, about 4.75x10® cells, or about 5.0x10scells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject atAttorney Docket No.: 132042-5007-WOa dose of about 1x10® to about 4x10® cells (e.g., viable cells) optionally with an immunosuppressive agent and / or antibiotic.

[0169] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of at least about 0.5x10sto at least about 5x10® cells. For example, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of at least about 0.5x10® cells, about 0.75x10® cells about 1.0x10® cells, about 1.25x10scells, about 1.5x106cells, about 1.75x10® cells, about 2.0x10® cells, about 2.25x10® cells, about 2.5x10® cells, about 2.75x10® cells, about 3.0x10® cells, about 3.25x10® cells, about 3.5x10® cells, about 3.75x10® cells, about 4.0x10scells, about 4.25x10® cells, at least 4.5x10® cells, about 4.75x 10® cells, or about 5.0x106cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject, at a dose of at least about 0.5x10® cells to at least about 1.0x10® cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of at least about 1.0x10® cells to at least about 1.5x10® cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of at least about 1.5x10® cells to at least about 2.0x10® cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of at. least about 2.0x10® cells to at least about 2.5x10® cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of at least about 2.5x10® cells to at least about 3.0x10® cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of at least about 3.0x106cells to at least about 3.5x106cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of at least about 3.5x10® cells to at least about 4.0x10® cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of at least about 4.0x106cells to at least about 4.5x10® cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of at least about 4.5x10® cells to at least about 5.0x10® cells. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered to a subject at a dose of at least about 1.0x10® to at least about 4.0x10® cells.Attorney Docket No.: 132042-5007-WO

[0170] After receiving any dose above, a subject may exhibit an improvement in visual function and / or functional vision. In some embodiments, visual function and / or functional vision is improved where, as compared to baseline, the human exhibits one or more of (or at least one of): a mean retinal sensitivity greater than or equal to seven decibels as measured by microperimetry, light sensitivity improvement as measured by full-field stimulus testing, a clinically significant improvement in retinal sensitivity as measured by static perimetry, a best corrected visual acuity (BCVA) greater than or equal to 0.3 Logarithm of the Minimum Angle of Resolution (LogMAR) units and > 15 Early Treatment of Diabetic Retinopathy Study (ETDRS) letter score, optionally wherein the human has a BCVA at baseline between about LogMAR 3.9 to about LogMAR 0.5 in a study eye and / or has an ETDRS letter score at baseline of 60 or less in the study eye, a low luminance visual acuity (LLVA) greater than or equal to 0.3 LogMAR units and > 15 ETDRS letter score, a clinically significant improvement in retinal sensitivity as measured by dark-adapted static perimetry, a clinically significant improvement in fixation location as measured by microperimetry, a clinically significant improvement in fixation stability as measured by microperimetry, a clinically significant improvement in color vision as measured by Hardy Rand and Rittler pseudoisochromatic test, a clinically significant improvement in quality of life scale scores as measured by the Michigan Retinal Degeneration Questionnaire (MRDQ) and / or the Michigan Vision-related Anxiety Questionnaire (MVAQ), an ability to navigate a multi-luminance navigation test, and / or an ability to navigate a multi-luminance navigation test at least two illumination levels lower.

[0171] In some embodiments, a subject is administered at least, about 0.5x106to at least about 5x106cells (e.g., in a composition comprising PRP cells described herein) and, after administration, the subject exhibits one or more of (or at least one of): a mean retinal sensitivity greater than or equal to seven decibels as measured by micro perimetry, light sensitivity improvement as measured by full-field stimulus testing, a clinically significant improvement in retinal sensitivity as measured by static perimetry, a best corrected visual acuity (BCVA) greater than or equal to 0.3 Logarithm of the Minimum Angle of Resolution (LogMAR) units and > 15 Early T reatment of Diabetic Retinopathy Study (ETDRS) letter score, optionally wherein the human has a BCVA at baseline between about LogMAR 3.9 to about LogMAR 0.5 in a study eye and / or has an ETDRS letter score at baseline of 60 or less in the study eye, a low luminance visual acuity (LLVA) greater than or equal to 0.3 LogMAR units and > 15 ETDRS letter score, a clinically significant improvement in retinal sensitivity as measured by dark-adapted static perimetry, a clinically significant improvement in fixation location as measured by microperimetry, a clinically significant improvement in fixation stability as measured by microperimetry, a clinically significantAttorney Docket No.: 132042-5007-WOimprovement in color vision as measured by Hardy Rand and Rittler pseudoisochromatic test, a clinically significant improvement in quality of life scale scores as measured by the Michigan Retinal Degeneration Questionnaire (MRDQ) and / or the Michigan Vision-related Anxiety Questionnaire (MVAQ), an ability to navigate a multi-luminance navigation test, and / or an ability to navigate a multi-luminance navigation test at least two illumination levels lower.

[0172] In some embodiments, a subject is administered (at least) about 1×106cells {e.g., in a composition comprising PRP ceils described herein) and, after administration, the subject exhibits one or more of (or at least one of): a mean retinal sensitivity greater than or equal to seven decibels as measured by microperimetry, light sensitivity improvement as measured by full-field stimulus testing, a clinically significant improvement in retinal sensitivity as measured by static perimetry, a best corrected visual acuity (BCVA) greater than or equal to 0.3 Logarithm of the Minimum Angle of Resolution (LogMAR) units and > 15 Early Treatment of Diabetic Retinopathy Study (ETDRS) letter score, optionally wherein the human has a BCVA at baseline between about LogMAR 3.9 to about LogMAR 0.5 in a study eye and / or has an ETDRS letter score at baseline of 60 or less in the study eye, a low luminance visual acuity (LLVA) greater than or equal to 0.3 LogMAR units and > 15 ETDRS letter score, a clinically significant improvement in retinal sensitivity as measured by dark-adapted static perimetry, a clinically significant improvement in fixation location as measured by microperimetry, a clinically significant improvement in fixation stability as measured by microperimetry, a clinically significant improvement in color vision as measured by Hardy Rand and Rittler pseudoisochromatic test, a clinically significant improvement in quality of life scale scores as measured by the Michigan Retinal Degeneration Questionnaire (MRDQ) and / or the Michigan Vision-related Anxiety Questionnaire (MVAQ), an ability to navigate a multi-luminance navigation test, and / or an ability to navigate a multi-luminance navigation test at least two illumination levels lower.

[0173] In some embodiments, a subject is administered (at least) about 2X106cells {e.g., in a composition comprising PRP cells described herein) and, after administration, the subject, exhibits one or more of (or at least one of): a mean retinal sensitivity greater than or equal to seven decibels as measured by microperimetry, light sensitivity improvement as measured by full-field stimulus testing, a clinically significant improvement in retinal sensitivity as measured by static perimetry, a best corrected visual acuity (BCVA) greater than or equal to 0.3 Logarithm of the Minimum Angle of Resolution (LogMAR) units and > 15 Early Treatment of Diabetic Retinopathy Study (ETDRS) letter score, optionally wherein the human has a BCVA at baseline between about LogMAR 3.9 to about LogMAR 0.5 in a study eye and / or has an ETDRS letter score at baselineAttorney Docket No.: 132042-5007-WOof 60 or less in the study eye, a low luminance visual acuity (LLVA) greater than or equal to 0.3 LogMAR units and > 15 ETDRS letter score, a clinically significant improvement in retinal sensitivity as measured by dark-adapted static perimetry, a clinically significant improvement in fixation location as measured by microperimetry, a clinically significant improvement in fixation stability as measured by microperimetry, a clinically significant improvement in color vision as measured by Hardy Rand and Rittler pseudoisochromatic test, a clinically significant improvement in quality of life scale scores as measured by the Michigan Retinal Degeneration Questionnaire (MRDQ) and / or the Michigan Vision-related Anxiety Questionnaire (MVAQ), an ability to navigate a multi-luminance navigation test, and / or an ability to navigate a multi-luminance navigation test at least two illumination levels lower.

[0174] In some embodiments, a subject is administered (at least) about 3x106cells (e.g., in a composition comprising PRP cells described herein) and, after administration, the subject exhibits one or more of (or at least one of): a mean retinal sensitivity greater than or equal to seven decibels as measured by microperimetry, light sensitivity improvement as measured by full-field stimulus testing, a clinically significant improvement in retinal sensitivity as measured by static perimetry, a best corrected visual acuity (BCVA) greater than or equal to 0.3 Logarithm of the Minimum Angle of Resolution (LogMAR) units and > 15 Early Treatment of Diabetic Retinopathy Study (ETDRS) letter score, optionally wherein the human has a BCVA at baseline between about LogMAR 3.9 to about LogMAR 0.5 in a study eye and / or has an ETDRS letter score at baseline of 60 or less in the study eye, a low luminance visual acuity (LLVA) greater than or equal to 0.3 LogMAR units and > 15 ETDRS letter score, a clinically significant improvement in retinal sensitivity as measured by dark-adapted static perimetry, a clinically significant improvement in fixation location as measured by microperimetry, a clinically significant improvement in fixation stability as measured by microperimetry, a clinically significant improvement in color vision as measured by Hardy Rand and Rittler pseudoisochromatic test, a clinically significant improvement in quality of life scale scores as measured by the Michigan Retinal Degeneration Questionnaire (MRDQ) and / or the Michigan Vision-related Anxiety Questionnaire (MVAQ), an ability to navigate a multi-luminance navigation test, and / or an ability to navigate a multi-luminance navigation test at least two illumination levels lower.

[0175] In some embodiments, a subject is administered (at least) about 4x106cells (e.g., in a composition comprising PRP cells described herein) and, after administration, the subject exhibits one or more of (or at least one of): a mean retinal sensitivity greater than or equal to seven decibels as measured by microperimetry, light sensitivity improvement as measured by full-fieldAttorney Docket No.: 132042-5007-WOstimulus testing, a clinically significant improvement in retinal sensitivity as measured by static perimetry, a best corrected visual acuity (BCVA) greater than or equal to 0.3 Logarithm of the Minimum Angle of Resolution (LogMAR) units and > 15 Early Treatment of Diabetic Retinopathy Study (ETDRS) letter score, optionally wherein the human has a BCVA at baseline between about LogMAR 3.9 to about LogMAR 0.5 in a study eye and / or has an ETDRS letter score at baseline of 60 or less in the study eye, a low luminance visual acuity (LLVA) greater than or equal to 0.3 LogMAR units and > 15 ETDRS letter score, a clinically significant improvement in retinal sensitivity as measured by dark-adapted static perimetry, a clinically significant improvement in fixation location as measured by microperimetry, a clinically significant improvement in fixation stability as measured by microperimetry, a clinically significant improvement in color vision as measured by Hardy Rand and Rittler pseudoisochromatic test, a clinically significant improvement in quality of life scale scores as measured by the Michigan Retinal Degeneration Questionnaire (MRDQ) and / or the Michigan Vision-related Anxiety Questionnaire (MVAQ), an ability to navigate a multi-luminance navigation test, and / or an ability to navigate a multi-luminance navigation test at least two illumination levels lower.

[0176] In some embodiments, a subject is administered (at least) about 5*106cells (e.g., in a composition comprising PRP cells described herein) and, after administration, the subject exhibits one or more of (or at least one of): a mean retinal sensitivity greater than or equal to seven decibels as measured by microperimetry, light sensitivity improvement as measured by full-field stimulus testing, a clinically significant improvement in retinal sensitivity as measured by static perimetry, a best corrected visual acuity (BCVA) greater than or equal to 0.3 Logarithm of the Minimum Angle of Resolution (LogMAR) units and > 15 Early Treatment of Diabetic Retinopathy Study (ETDRS) letter score, optionally wherein the human has a BCVA at baseline between about LogMAR 3.9 to about LogMAR 0.5 in a study eye and / or has an ETDRS letter score at baseline of 60 or less in the study eye, a low luminance visual acuity (LLVA) greater than or equal to 0.3 LogMAR units and > 15 ETDRS letter score, a clinically significant improvement in retinal sensitivity as measured by dark-adapted static perimetry, a clinically significant improvement in fixation location as measured by microperimetry, a clinically significant improvement in fixation stability as measured by microperimetry, a clinically significant improvement in color vision as measured by Hardy Rand and Rittler pseudoisochromatic test, a clinically significant improvement in quality of life scale scores as measured by the Michigan Retinal Degeneration Questionnaire (MRDQ) and / or the Michigan Vision-related Anxiety Questionnaire (MVAQ), an ability to navigate a multi-luminance navigation test, and / or an ability to navigate a multi-luminance navigation test at least two illumination levels lower.Attorney Docket No.: 132042-5007-WO

[0177] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered at a single time to the subject. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be administered at multiple times (e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10 or more times) to the subject.

[0178] In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be surgically administered to a target site in the subject. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be surgically administered as a single dose. In some embodiments, the therapeutically effective amount of the composition comprising photoreceptor precursor cells may be surgically administered in multiple doses. The composition comprising PRP cells may be introduced into the target site in the form of cell suspension, or adhered onto a matrix, extracellular matrix, or substrate such as a biodegradable polymer, as a monolayer, or a combination. The composition comprising PRP cells may be introduced into the target site in the form of a cell suspension comprising cell aggregates.

[0179] In some embodiments, the composition comprising PRP cells is formulated as a pharmaceutical composition or a drug product. In some embodiments, the pharmaceutical composition or the drug product comprises the composition of PRP cells and CryoSTOR® cell cryopreservation media (CS10). In some embodiments, composition comprising PRP cells is formulated into a drug product by resuspension in a DMSO-containing cryopreservation medium and asepctic transfer into a vial. In some embodiments, the drug product is then frozen using liquid nitrogen. Alternatively, the cells may be cryopreserved as aggregates without dissociation into a single cell suspension, such as at 25x106aggregated cell products / vial.

[0180] In some embodiments, the drug product is formulated into a dose for administration by thawing, washing, and diluting with a vehicle solution. In some embodiments, the vehicle solution is Balanced Salt Solution (BSS®) Sterile Irrigating Solution supplemented with about 0.2% Human Serum Albumin (HSA). In some embodiments, aggregates are enriched with slow-rate centrifugation. In some embodiments, a live cell concentration and / or percentage viability is assessed for the dose for administration. In some embodiments, the concentration of cells may be adjusted by dilution or centrifugation with resuspension. In some embodiments, the dose for administration is further assessed for sterility, endotoxin levels, and / or visual appearance.Attorney Docket No.: 132042-5007-WO

[0181] In some embodiments, to prepare a dose for administration (DfA), the drug product (DP) may be formulated by thawing, washing, and diluting with a vehicle solution. The vehicle solution may comprise Balanced Salt Solution (BSS®) Sterile Irrigating Solution supplemented with about 0.2% Human Serum Albumin (HSA). In some embodiments, the number of DP vials to thaw may be calculated based on the target dose concentraton and live cell concentration of the DP. In some embodiments, after the cells are pooled and the cryopreservation buffer is diluted, the aggregates may be enriched via slow-rate centrifugation, and the supernatant may be removed. In some embodiments, a fixed volume vehicle solution may be added to the tube to resuspend the cells. In some embodiments, the enriched aggregate suspension may be centrifuged again, and the supernatant may be removed. In some embodiments, the cell pellet may be resuspended again in a fixed volume of vehicle solution, the tube may be centrifuged again, and the supernatant may be removed to a targeted volume. In some embodiments, the pelleted cells may be respusended within the targeted volume to create the bulk dose. In some embodiments, the master dose may be prepared at the target live cell concentration for further DfA container closure fill. In some embodiments, about one adjustment of the live cell concentration to within the allowable range may be performed. In some embodiments, a calculated volume of the bulk dose may be transferred to a new tube and re-suspended in a designated volume of vehicle solution based on the bulk dose live cell concentration result. In some embodiments, this step may formulate the target master dose based on the intended clinical dose level. In some embodiments, the master dose may be then sampled for total and live cell concentration to enable calculation of percent viability. In some embodiments, if the enumeration does not meet the assay validity criteria, about one re-sampling may be performed. In some embodiments, if the repeated master dose enumeration fails, the run may be terminated. In some embodiments, when a valid result is obtained, if the live cell concentration is not within the allowable range for the intended clinical dose, the master dose concentration may be adjusted. In some embodiments, if the viability does not meet the specification, the run may be terminated. In some embodiments, if both criteria are met, the adjusted master dose may be filled into the DfA container closure.

[0182] In some embodiments, the master dose may be adjusted to within the allowable live cell concentration range. In some embodiments, if the master dose needs to be diluted to a lower live cell concentration, vehicle solution may be added to the master dose and mixed. If the master dose needs to be concentrated, the cells are pelleted via centrifugation and a calculated volume of supernatant is removed from the dose. In some embodiments, the adjusted master dose may be then mixed to resuspend the cells and sampled for total and live cell concentration to enable calculation of percent viability. In some embodiments, if the enumeration does not meet the assayAttorney Docket No.: 132042-5007-WOvalidity criteria, about one re-sampling may be performed. In some embodiments, if the repeated adjusted master dose enumeration fails, the run may be terminated. In some embodiments, when a valid result is obtained, if the live cell concentration is not within the allowable range for the intended clinical dose or if the viability does not meet the specification, the run may be terminated. In some embodiments, if both criteria are met, the adjusted master dose may be filled into the DfA container closure.

[0183] In some embodiments, the time at which the final master dose was prepared may be recorded, and the expiry time and date may be calcuated from this value and recorded. In some embodiments, the final master dose may be used to fill two doses of 50 pL each (1 clinical dose and 1 back-up dose) into pre-inspected tubes after uniformly resuspending the master dose by gentle pipetting. In some embodiments, six 1.5 mL aliquots of vehicle solution may be filled into pre-inspected tubes. In some embodiments, the final live cell concentration and percent viability determined from enumeration of the master dose may be recorded for release of the DfA. In some embodiments, additional samples of the master dose and the vehicle solution may be taken for sterilty and endotoxin testing. In some embodiments, appearance may be evaluated by visual inspection of the final DfA and vehicle solution in their respective container closure systems. In some embodiments, interim release of the DfA for patient administration is based upon appearance, viability, live cell concentration, and endotoxin testing wherease interim release of vehicle solution for patient administration is based upon appearance and endotoxin testing. _ln some embodiments, primary container labels may be applied across the top of each respective DfA and vehicle solution tube such that the ends of the labels adhere to the rack the tube is contained in, and each rack containing tubes is packaged in a sterile sampling bag and maintained at about 1°C to about 8 °C. In some embodiments, the packaged racks, DfA and vehicle solution tubes are transferred to overnight storage until interim QC testing and interim release of the DfA and vehicle solution have been completed. In some embodiments, after overnight storage, DfA and vehicle solution packages may be transferred to a temperature-controlled package which may be monitored during transportation to the surgical administration site.

[0184] In some embodiments, the resulting cell population comprises AIPL1+ and RCVRN+ iPRP cells subdivided by NR2E3+ rod-committed PRP cells and PPP4R4+ cone-commited iPRP cells with minimally detected CHX10+, PAX6+, TYRP1+, and Ki67+ off-target cells, minimally detected VIM gene expression, and no detectable LNCPRESS2 and AC009446.1 gene expression.Attorney Docket No.: 132042-5007-WO

[0185] In some embodiments, the composition comprising PRP cells is formulated as a pharmaceutical composition or a dose for administration. In some embodiments, the pharmaceutical composition or the dose for administration comprises the composition of PRP cells, a Balanced Salt Solution (BSS™ Sterile Irrigating Solution; Alcon Laboratories, Inc. Cat. No.65079550), and / or Human Serum Albumin (HSA; Octapharma Cat. No. 68982-0643-02). In some embodiments, the BSS comprises magnesium chloride, calcium chloride, potassium chloride, sodium citrate, sodium acetate, and / or sodium chloride.

[0186] In some embodiments, the balanced salt solution comprises about 0.0 mg / mL to about 1.50 mg / mL of magnesium chloride, about 0.0 mg / mL to about 1.5 mg / mL of calcium chloride, about 0.0 mg / mL to about 1.5 mg / mL of potassium chloride, about 0.0 mg / mL to about 3.0 mg / mL of sodium citrate, about 0.0 mg / mL to about 6.0 mg / mL of sodium acetate, and / or about 0.0 mg / mL to about 10.0 mg / mL of sodium chloride. In some embodiments, the balanced salt solution comprises about 0.0 mg / mL, about 0.10 mg / mL, about 0.20 mg / mL, about 0.30 mg / mL, about 0.40 mg / mL, about 0.50 mg / mL, about 0.60 mg / mL, about 0.70 mg / mL, about 0.80 mg / mL, about 0.90 mg / mL, about 1.00 mg / mL, about 1.10 mg / mL, about 1.20 mg / mL, about 1.30 mg / mL, about 1.40 mg / mL, or about 1.50 mg / mL of magnesium chloride. In some embodiments, the balanced salt solution comprises about 0.0 mg / mL, about 0.10 mg / mL, about 0.20 mg / mL, about 0.30 mg / mL, about 0.40 mg / mL, about 0.50 mg / mL, about 0.60 mg / mL, about 0.70 mg / mL, about 0.80 mg / mL, about 0.90 mg / mL, about 1.00 mg / mL, about 1.10 mg / mL, about 1.20 mg / mL, about 1.30 mg / mL, about 1.40 mg / mL, or about 1.50 mg / mL of calcium chloride. In some embodiments, the balanced salt solution comprises about 0.0 mg / mL, about 0.10 mg / mL, about 0.20 mg / mL, about 0.30 mg / mL, about 0.40 mg / mL, about 0.50 mg / mL, about 0.60 mg / mL, about 0.70 mg / mL, about 0.80 mg / mL, about 0.90 mg / mL, about 1.00 mg / mL, about 1.10 mg / mL, about 1.20 mg / mL, about 1.30 mg / mL, about 1.40 mg / mL, or about 1.50 mg / mL of potassium chloride. In some embodiments, the balanced salt solution comprises about 0.0 mg / mL, about 0.10 mg / mL, about 0.20 mg / mL, about 0.30 mg / mL, about 0.40 mg / mL, about 0.50 mg / mL, about 0.60 mg / mL, about 0.70 mg / mL, about 0.80 mg / mL, about 0.90 mg / mL, about 1.00 mg / mL, about 1.10 mg / mL, about 1.20 mg / mL, about 1.30 mg / mL, about 1.40 mg / mL, 1.50 mg / mL, about 1.60 mg / mL, about 1.70 mg / mL, about 1.80 mg / mL, about 1.90 mg / mL, about 2.00 mg / mL, about 2.10 mg / mL, about 2.20 mg / mL, about 2.30 mg / mL, about 2.40 mg / mL, about 2.50 mg / mL, about 2.60 mg / mL, about 2.70 mg / mL, about 2.80 mg / mL, about 2.90 mg / mL, or about 3.00 mg / mL of sodium citrate. In some embodiments, the balanced salt solution comprises about 0.0 mg / mL, about 0.25 mg / mL, about 0.50 mg / mL, about 0.75 mg / mL, about 1.00 mg / mL, about 1.25 mg / mL, about 1.50 mg / mL, about 1.75 mg / mL, about 2.00 mg / mL, about 2.25 mg / mL, about 2.50 mg / mL, about 2.75 mg / mL, aboutAttorney Docket No.: 132042-5007-WO3.00 mg / mL, about 3.25 mg / mL, about 3.50 mg / mL, 3.75 mg / mL, about 4.00 mg / mL, about 4.25 mg / mL, about 4.50 mg / mL, about 4.75 mg / mL, about 5.00 mg / mL, about 5.25 mg / mL, about 5.50 mg / mL, about 5.75 mg / mL, or about 6.00 mg / mL of sodium acetate. In some embodiments, the balanced salt solution comprises about 0.0 mg / mL, about 0.50 mg / mL, about 1.00 mg / mL, about 1.50 mg / mL, about 2.50 mg / mL, about 3.00 mg / mL, about 3.50 mg / mL, about 4.00 mg / mL, about 4.50 mg / mL, about 5.00 mg / mL, about 5.50 mg / mL, about 6.00 mg / mL, about 6.50 mg / mL, about 7.00 mg / mL, 7.50 mg / mL, about 8.00 mg / mL, about 8.50 mg / mL, about 9.00 mg / mL, about 9.50 mg / mL, or about 10.00 mg / mL of sodium chloride.

[0187] In some embodiments, the human serum albumin is at a concentration of about 0.0% to about 1.0% (e.g., about 0.0% to about 1.0%, about 0.0% to about 0.9%, about 0.0% to about 0.8%, about 0.0% to about 0.7%, about 0.0% to about 0.6%, about 0.0% to about 0.5%, about 0.0% to about 0.4%, about 0.0% to about 0.3%, about 0.0% to about 0.2%, about 0.0% to about 0.1%, about 0.1% to about 1.0%, about 0.1% to about 0.9%, about 0.1% to about 0.8%, about 0.1% to about 0.7%, about 0.1% to about 0.6%, about 0.1% to about 0.5%, about 0.1% to about 0.4%, about 0.1% to about 0.3%, about 0.1% to about 0.2%, about 0.2% to about 1.0%, about 0.2% to about 0.9%, about 0.2% to about 0.8%, about 0.2% to about 0.7%, about 0.2% to about 0.6%, about 0.2% to about 0.5%, about 0.2% to about 0.4%, about 0.2% to about 0.3%, about 0.3% to about 1.0%, about 0.3% to about 0.9%, about 0.3% to about 0.8%, about 0.3% to about 0.7%, about 0.3% to about 0.6%, about 0.3% to about 0.5%, about 0.3% to about 0.4%, about 0.4% to about 1.0%, about 0.4% to about 0.9%, about 0.4% to about 0.8%, about 0.4% to about 0.7%, about 0.4% to about 0.6%, about 0.4% to about 0.5%, about 0.5% to about 1.0%, about 0.5% to about 0.9%, about 0.5% to about 0.8%, about 0.5% to about 0.7%, about 0.5% to about 0.6%, about 0.6% to about 1.0%, about 0.6% to about 0.9%, about 0.6% to about 0.8%, about 0.6% to about 0.7%, about 0.7% to about 1.0%, about 0.7% to about 0.9%, about 0.7% to about 0.8%, about 0.8% to about 1.0%, about 0.8% to about 0.9%, or about 0.9% to about 1.0%). In some embodiments, the human serum albumin is at a concentration of about 0.0%, about 0.1%, about 0.2%, about 0.3%, about 0.4%, about 0.5%, about 0.6%, about 0.7%, about 0.8%, about 0.9%, or about 1.0%. In some embodiments, the human serum albumin is at a concentration of about 0.2%.

[0188] In some embodiments, the balanced salt solution comprises about 0.3 mg / mL of magnesium chloride, about 0.48 mg / mL of calcium chloride, about 0.75 mg / mL of potassium chloride, about 1.7 mg / mL of sodium citrate, about 3.9 mg / mL of sodium acetate, and / or aboutAttorney Docket No.: 132042-5007-WO6.4 mg / mL of sodium chloride. In some embodiments, the human serum albumin is at a concentration of about 0.2%.

[0189] In one aspect, the composition comprising PRP cells may treat or alleviate the symptoms of retinitis pigmentosa, cone-rod disease, rod-cone disease, cone dystrophies, cone-rod and / or rod-cone dystrophies, or Usher Syndrome. In a further aspect, the composition comprising PRPs may be administered in combination with other treatments including standard of care therapies.

[0190] The disclosure also provides methods of treating vision loss in a subject in need thereof, the methods comprising administering a therapeutically effective amount of one or more immunosuppressive agents to the subject. Such methods may further comprise administering a therapeutically effective amount of the composition comprising photoreceptor precursor cells into a subretinal space of an eye of the subject.

[0191] Additionally, the disclosure also provides methods of increasing a thickness of an outer nuclear layer of a retina of a human subject. Such methods may further comprise surgically administering a composition comprising a therapeutically effective amount of photoreceptor precursor cells to a subretinal space of an eye of the human subject. The disclosure also provides a composition comprising photoreceptor precursor cells (e.g., as described herein) for use in a method of treating vision loss in a subject, wherein the method further comprises administering one or more immunosuppressive agents to the subject. The disclosure also provides one or more immunosuppressive agents {e.g., as described herein) for use in a method of treating vision loss in a subject, wherein the method further comprises administering a composition comprising photoreceptor precursor cells (e.g., as described herein).

[0192] In some embodiments, the composition comprising PRPs may be administered via surgery using commercial, off-the-shelf ophthalmic and retinal surgical instruments. In some embodiments, the composition comprising PRP cells may be administered in a surgical suite under controlled aseptic conditions in a single surgical session while the subject is under general anesthesia.

[0193] In some embodiments, the subject may discontinue the use of aspirin, aspirin-containing products, and any other therapies that may alter coagulation for about one to about fourteen days before administration of the composition comprising PRP cells. In some embodiments, the subject may discontinue the use of aspirin, aspirin-containing products, and any other therapies that may alter coagulation for at least about one, at least about two, at least about three, at least about four, at least about five, at least about six, at least about seven, at least about eight, at least aboutAttorney Docket No.: 132042-5007-WOnine, at least about ten, at least about eleven, at least about twelve, at least about thirteen, or at least about fourteen days before administration of the composition comprising PRP cells. In some embodiments, the subject may discontinue the use of aspirin, aspirin-containing products, and any other therapies that may alter coagulation for at least about seven days before administration of the composition comprising PRP cells.

[0194] In some embodiments, a surgical procedure may be carried out using a CONSTELLATION® Vision System (Alcon Science, Geneva, Switzerland). In some embodiments, the surgical procedure may be monitored using an operating microscope and / or intraoperative optical coherence tomography (iOCT).

[0195] A selection of a retinotomy site (e.g., retinal cut site) and an intended pre-bleb and / or bleb location may occur prior to the surgical procedure. In some embodiments, an area demonstrating ellipsoid zone loss with preservation of inner nuclear layer and retinal pigment epithelium (RPE) within or adjacent to the subject’s macula may be targeted for administration of the composition comprising PRPs. The intended pre-bleb and / or bleb location may avoid areas of excessive atrophy, epiretinal membranes, and / or the fovea. Additionally, the retinotomy site may avoid the papillomacular bundle region. In some embodiments, the retinotomy may be placed in the superior retina posterior to the superior arcade vessels, near a crossing of vessels. In other embodiments, the bleb may be a perifoveal bleb in the superior macula. In other embodiments, the retinotomy site may be placed along the supero- or inferotemporal vascular arcades.

[0196] The subject may undergo a vitrectomy to remove the vitreous prior to administration of the composition comprising PRP cells. In some embodiments, the subject may undergo a vitrectomy and an iatrogenic retinal detachment prior to the administration of the composition comprising PRP cells. In some embodiments, the vitrectomy and / or the iatrogenic retinal detachment occurs in the same eye that the composition comprising PRP cells will be administered. In some embodiments, the vitrectomy may be through the pars plana. In some embodiments, the vitrectomy may be a three-port pars plana vitrectomy. In some embodiments, the three-port pars plana vitrectomy may have scleral entry sites superonasal, superotemporal, and inferotemporal. In some embodiments, the three-port pars plana vitrectomy may be executed using a light pipe, a vitrectomy cutter, and / or an infusion cannula. Basic vitreoretinal procedure components for operating the Constellation system may be provided in the CONSTELLATION® Vitrectomy 25G TOTAL PLUS Pak, including a light pipe, a vitrector, fluidics, tubing, and a cassette.Attorney Docket No.: 132042-5007-WO

[0197] In some embodiments, a subretinal pre-bleb may be created to detach the retina and form a potential space using vehicle solution (BSSTMSterile Irrigating Solution [balanced salt solution] (Alcon Laboratories, Inc., Geneva, Switzerland) supplemented with about 0.02% to about 0.40% human serum albumin), followed by the withdrawal of vehicle solution (e.g., the majority of vehicle solution) to reduce tension within the potential space. In some embodiments, the vehicle solution of BSS™ Sterile Irrigating Solution may be supplemented with about 0.02%, about 0.04%, about 0.06%, about 0.08%, about 0.10%, about 0.12%, about 0.14%, about 0.16%, about 0.18%, about 0.20%, about 0.22%, about 0.24%, about 0.26%, about 0.28%, about 0.30%, about 0.32%, about 0.34%, about 0.36%, about 0.38%, or about 0.40% human serum albumin. In some embodiments, the vehicle solution of BSS™ Sterile Irrigating Solution may be supplemented with about 0.20% human serum albumin.

[0198] In some embodiments, the subretinal pre-bleb may be created with about 100 pLto about 300 pLof the vehicle solution. In some embodiments, the subretinal pre-bleb may be created with about 100 pL, about 105 pL, about 110 pL, about 115 pL, about 120 pL, about 125 pL, about 130 pL, about 135 pL, about 140 pL, about 145 pL, about 150 pL, about 155 pL, about 160 pL, about 165 pL, about 170 pL, about 175 pL, about 180 pL, about 185 pL, about 190 pL, about 195 pL, about 200 pL, about 205 pL, about 210 pL, about 215 pL, about 220 pL, about 225 pL, about 230 pL, about 235 pL, about 240 pL, about 245 pL, about 250 pL, about 255 pL, about 260 pL, about 265 pL, about 270 pL, about 275 pL, about 280 pL, about 285 pL, about 290 pL, about 295 pL, or about 300 pL of the vehicle solution. In some embodiments, the subretinal pre-bleb may be created with about 150 pL of the vehicle solution.

[0199] In some embodiments, the pre-bleb may be used to create a subretinal space which provides a larger treatment area for PRP cell dispersal and reduces reflux (e.g., improper release of the PRP cells outside of intended bleb) of the transplanted cells.

[0200] In some embodiments, the pre-bleb may be about 3 to about 11 disc diameters in size. In some embodiments, the pre-bleb may be about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, or about 11 disc diameters in size. In some embodiments, the pre-bleb may be about 6, about 7, or about 8 disc diameters in size. In some embodiments, the pre-bleb solution may be injected with a 38-gauge cannula. In some embodiments, the 38-gauge cannula may be a MedOne PolyTip Cannula 25G / 38G.

[0201] In some embodiments, between about 50% and about 90% of the pre-bleb solution may be subsequently removed. In some embodiments, about 50%, about 55%, about 60%, aboutAttorney Docket No.: 132042-5007-WO65%, about 70%, about 75%, about 80%, about 85%, or about 90% of the pre-bleb solution may be subsequently removed. In some embodiments, about 75% of the pre-bleb solution may be subsequently removed. In some embodiments, the composition comprising PRP cells may then then be injected into the subretinal space as a bleb. In some embodiments, the pre-bleb location may be the same as the site of administration of the bleb location {e.g., the site of PRP surgical administration).

[0202] In some embodiments, a pharmaceutical composition comprising PRP cells may exhibit an endotoxin level of less than or equal to about 5.00 EU / mL as determined by Nexgen Endosafe Systems (Charles River Laboratories, Wilmington, MA). In some embodiments, the pharmaceutical composition comprising PRP cells may exhibit an endotoxin level of about 0.00 EU / mL, about 0.25 EU / mL, about 0.50 EU / mL, about 0.75 EU / mL, about 1.00 EU / mL, about 1.25 EU / mL, about 1.50 EU / mL, about 1.75 EU / mL, about 2.00 EU / mL, about 2.25 EU / mL, about 2.50 EU / mL, about 2.75 EU / mL, about 3.00 EU / mL, about 3.25 EU / mL, about 3.50 EU / mL, about 3.75 EU / mL, about 4.00 EU / mL, about 4.25 EU / mL, about 4.50 EU / mL, about 4.75 EU / mL, or about 5.00 EU / mL as determined by Nexgen Endosafe Systems. In some embodiments the pharmaceutical composition comprising PRP cells exhibit an endotoxin level of less than about 0.025 EU / mL.

[0203] In some embodiments, a pharmaceutical composition comprising PRP cells may appear as white or off white settled cells upon visual inspection. In some embodiments, the pharmaceutical composition comprising PRP cells may appear as a homogenous cell suspension upon visual inspection. In some embodiments, the pharmaceutical composition comprising PRP cells may appear as a translucent, colorless fluid. In other embodiments, the pharmaceutical composition comprising PRP cells may appear as an opaque, colorless fluid. In some embodiments, the pharmaceutical composition comprising the PRP cells may appear essentially free of visible particulates and foreign matter. In some embodiments, the pharmaceutical composition comprising PRP cells may appear as white or off-white settled cells or homologous cell suspension, in a translucent or opaque colorless fluid, essentially free of visible particulates and foreign matter.

[0204] In some embodiments, a pharmaceutical composition comprising PRP cells may be maintained between about 1 °C to about 8 °C prior to administration to the subject. In some embodiments, the composition comprising PRP cells may be maintained at about 1 °C, about 2 °C, about 3 °C, about 4 °C, about 5 °C, about 6 °C, about 7 °C, or about 8 °C prior to administration. In some embodiments, the pharmaceutical composition comprising PRP cells mayAttorney Docket No.: 132042-5007-WObe resuspended prior to administration. In some embodiments, the pharmaceutical composition comprising PRP cells may be resuspended by flicking or slinging. In some embodiments, the composition comprising resuspended PRP cells may be drawn into a 33-gauge PolyTip Funnel cannula prior to administration.

[0205] In some embodiments, the pharmaceutical composition comprising PRP cells may be surgically administered as a one-time injection at about 10 pl to about 100 pL volume into the subretinal space of the subject’s eye (e.g., one eye only) after pars plana vitrectomy. In some embodiments, the pharmaceutical composition comprising PRP cells may be surgically administered as a one-time injection at about 10 pL, about 15 pL, about 20 pL, about 25 pL, about 30 pL, about 35 pL, about 40 pL, about 45 pL, about 50 pL, about 55 pL, about 60 pL, about 65 pL, about 70 pL, about 75 pL, about 80 pL, about 85 pL, about 90 pL, about 95 pL, or about 100 pL volume into the subretinal space of the subject’s eye (e.g., one eye only) after pars plana vitrectomy. In some embodiments, the pharmaceutical composition comprising PRP cells may be surgically administered as a one-time injection at about 50 pL volume into the subretinal space of the subject’s eye (e.g., one eye only) after pars plana vitrectomy.

[0206] In some embodiments, the one-time injection may be administered into the worse seeing eye after pars plana vitrectomy. In some embodiments, the one-time injection may be administered into both eyes of the subject after pars plana vitrectomy. In some embodiments, the pharmaceutical composition comprising PRP cells may be injected into the subretinal space using a 33-gauge funnel cannula. In some embodiments, the 33-gauge funnel cannula may be a MedOne PolyTip Funnel Cannula 25G / 33G. In some embodiments, the pharmaceutical composition comprising PRP cells may be administered at the same site as the retinotomy made during the pre-bleb creation. In some embodiments, the bleb may be raised in the superior macula without lifting the fovea. In some embodiments, the bleb may be raised by lifting the fovea to create a subfoveal bleb. In some embodiments, the bleb may be about 3 to about 11 disc diameters in size. In some embodiments, the bleb may be about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, or about 11 disc diameters in size. In some embodiments, the bleb may be about 6, about 7, or about 8 disc diameters in size.

[0207] In some embodiments, the pharmaceutical composition comprising PRP cells may be transplanted in combination with other retinal cells, such as with photoreceptors. Transplantation of the pharmaceutical composition comprising PRP cells may be performed by various techniques known in the art. In accordance with one embodiment, the transplantation may be performed via pars plana vitrectomy surgery followed by delivery of the cells through a small retinal opening intoAttorney Docket No.: 132042-5007-WOthe subretinal space or by direct injection. The pharmaceutical composition comprising PRP cells may be introduced into the target site in the form of cell suspension, cell aggregates, or adhered onto a matrix, such as extracellular matrix.

[0208] In some embodiments, a composition comprising photoreceptor precursor cells (e.g., a pharmaceutical composition of PRP cells) can include at least about 1*103to about 1xio9PRP cells. In some embodiments, a composition of photoreceptor precursor cells can include at least about 1x3PRP cells, about 1xio4PRP cells, about 1xio5PRP cells, about 1×106PRP cells, about 1 X107PRP cells, about 1xio8PRP cells, or about 1 X109PRP cells. In some embodiments, a composition comprising photoreceptor precursor cells can include at least about 1×106PRP cells. In some embodiments, a composition comprising photoreceptor precursor cells can include at least about 2X106PRP cells. In some embodiments, a composition comprising photoreceptor precursor cells can include at least about 3X106PRP cells. In some embodiments, a composition comprising photoreceptor precursor cells can include at least about 4x10® PRP cells. In certain embodiments, the compositions may be substantially purified (with respect to non-PRP cells) preparations comprising differentiated and / or matured PRP cells. The cells may be provided as a monolayer of cells or as a composition comprising aggregated cells.

[0209] In some embodiments, the live cell concentration of a pharmaceutical composition comprising PRP cells may be calculated using automated cell counting with acridine orange and / or propidium iodide using, for example, a Cellaca™ MX High Throughput Cell Counter (Revvity, Waltham, MA, Part No.: MX-AOPI). In some embodiments, the live cell concentration of the pharmaceutical composition comprising PRP cells for a dose comprising about 1×106PRP cells per 50 pL may have a concentration of about 2.72x107cells / mL to about 4.08x107cells / mL as determined by automated cell counting. In some embodiments, the live cell concentration of the pharmaceutical composition comprising PRP cells for a dose comprising about 2x106PRP cells per 50 pL may have a concentration of about 5.04X107cells / mL to about 7.56X107cells / mL as determined by automated cell counting. In some embodiments, the live cell concentration of the pharmaceutical composition comprising PRP cells for a dose comprising about 3x106PRP cells per 50 pL may have a concentration of about 7.12x107cells / mL to about 1.07x108cells / mL as determined by automated cell counting. In some embodiments, the live cell concentration of the pharmaceutical composition comprising PRP cells for a dose comprising about 4x106PRP cells per 50 pL may have a concentration of about 9.44X107cells / mL to about 1.42x10scells / mL as determined by automated cell counting.Attorney Docket No.: 132042-5007-WO

[0210] In some embodiments, a percentage cell viability of a pharmaceutical composition comprising PRP cells may be calculated using automated cell counting with acridine orange and / or propidium iodide using, for example, a Cellaca™ MX. In some embodiments, the percentage viability of the pharmaceutical composition comprising PRP cells may be calculated to be between about 30% and about 110%. In some embodiments, the percentage viability of the pharmaceutical composition comprising PRP cells may be calculated to be about 30%, about 31%, about 32%, about 33%, about 34%, about 35%, about 36%, about 37%, about 38%, about 39%, about 40%, about 41%, about 42%, about 43%, about 44%, about 45%, about 46%, about 47%, about 48%, about 49%, about 50%, about 51%, about 52%, about 53%, about 54%, about 55%, about 56%, about 57%, about 58%, about 59%, about 60%, about 61%, about 62%, about 63%, about 64%, about 65%, about 66%, about 67%, about 68%, about 69%, about 70%, about 71%, about 72%, about 73%, about 74%, about 75%, about 76%, about 77%, about 78%, about 79%, about 80%, about 81%, about 82%, about 83%, about 84%, about 85%, about 86%, about 87%, about 88%, about 89%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, about 100%, about 101%, about 102%, about 103%, about 104%, about 105%, about 106%, about 107%, about 108%, about 109%, or about 110%. In some embodiments, the percentage viability of the pharmaceutical composition comprising PRP cells may be calculated to be at least about 40%.

[0211] In some embodiments, the sterility of the pharmaceutical composition comprising PRP cells may be assessed for contaminant growth. In some embodiments, the pharmaceutical composition comprising PRP cells may exhibit no contaminant growth.

[0212] In some embodiments, an intraocular dexamethasone intravitreal implant may be delivered about 1 mm to about 5 mm posterior to the limbus after the administration of the composition comprising PRP cells. In some embodiments, an intraocular dexamethasone intravitreal implant may be delivered about 1.0 mm, about 1.5 mm, about 2.0 mm, about 2.5 mm, about 3.0 mm, about 3.5 mm, about 4.0 mm, about 4.5 mm, about 5.0 mm, about 5.5 mm, or about 6.0 mm posterior to the limbus after the administration of the composition comprising PRP cells. In some embodiments, an intraocular dexamethasone intravitreal implant may be delivered about 3.5 mm posterior to the limbus after the administration of the composition comprising PRP cells. In some embodiments, the intraocular dexamethasone intravitreal implant may be delivered away from the bleb so as not to disturb the subretinally transplanted PRP cells.

[0213] In some embodiments, betamethasone may be administered after the administration of the composition comprising PRP cells. In some embodiments, betamethasone may beAttorney Docket No.: 132042-5007-WOadministered at about 0.1 mL to about 1.0 mL as a subconjunctival injection. In some embodiments, betamethasone may be administered in about 0.1 mL, about 0.2 mL, about 0.3 mL, about 0.4 mL, about 0.5 mL, about 0.6 mL, about 0.7 mL, about 0.8 mL, about 0.9 mL, or about 1.0 mL as a subconjunctival injection. In some embodiments, betamethasone may be administered as a 0.5 mL subconjunctival injection. In some embodiments, any sclerotomies may be closed using water-tight sutures to reduce the risk of postoperative hypotony after the administration of the composition comprising PRP cells. In some embodiments, atropine and either bacitracin zinc / polymyxin B sulfate ointment or neomycin / polymyxin B sulfate / dexamethasone ophthalmic ointment may be administered to the subject after the administration of the composition comprising PRP cells.

[0214] In some embodiments, the subject may be monitored in a post-anesthesia care unit after the administration of the composition comprising PRP cells. In some embodiments, the subject may remain in a supine position for about one hour to about six hours in the post-anesthesia care unit. In some embodiments, the subject may remain in the supine position for about one, about two, about three, about four, about five, or about six hours in the post-anesthesia care unit. In some embodiments, the subject may remain in a supine position for at least about two hours in the post-anesthesia care unit. In some embodiments, the subject may remain in the supine position for about four hours in the post-anesthesia care unit. In some embodiments, the subject may remain in the supine position for as much time as physically feasible for up to about 48 hours after the administration of the composition comprising PRP cells.

[0215] In some embodiments, the subject may also be administered an immunosuppressive (IS) regimen. In some embodiments, the IS regimen begins about 1 day to about 30 days prior to the dose of the composition comprising the photoreceptor precursor cells. In some embodiments, the IS regimen begins about 30, about 29, about 28, about 27, about 26, about 25, about 24, about 23, about 22, about 21, about 20, about 19, about 18, about 17, about 16, about 15, about 14, about 13, about 12, about 11, about 10, about 9, about 8, about 7, about 6, about 5, about 4, about 3, about 2, or about 1 day prior to the dose of the therapeutically effective amount of the composition comprising photoreceptor precursor cells. In some embodiments, the IS regimen begins 21 days prior to the dose of the therapeutically effective amount of the composition comprising photoreceptor precursor cells. In some embodiments, the IS regimen begins 14 days prior to the dose of the therapeutically effective amount of photoreceptor precursor cells.

[0216] In some embodiments, the subject will receive an IS regimen in order to minimize the risk of rejection of the PRP cells and optimize cell survival and engraftment. The IS regimen mayAttorney Docket No.: 132042-5007-WObe administered at various timepoints before, during, and after treatment. In some embodiments, the subject will receive tacrolimus and mycophenolic acid (MPA) prior to administration of the composition comprising PRP cells. Tacrolimus is a calcineurin inhibitor that suppresses T-cell responses. M A is an antimetabolite immunosuppressant that has cytostatic effects on T- and B-lymphocytes. Both drugs have been extensively studied, have established safety profiles, and are generally well tolerated both alone and in combination (Tacrolimus PI, 2012; Myfortic PI, 2022).

[0217] In some embodiments, tacrolimus may be administered to the subject about one to about six weeks before the administration of the composition comprising PRP cells at a daily dose of about 0.005 mg / kg to about 0.100 mg / kg. In some embodiments, tacrolimus may be administered to the subject about one, about two, about three, about four, about five, or about six weeks before the administration of the composition comprising PRP cells. In some embodiments, tacrolimus may be administered at a daily dose of about 0.005, about 0.010 mg / kg, about 0.015 mg / kg, about 0.020 mg / kg, about 0.025 mg / kg, about 0.030 mg / kg, about 0.035 mg / kg, about 0.040 mg / kg, about 0.045 mg / kg, about 0.050 mg / kg, about 0.055 mg / kg, about 0.060 mg / kg, about 0.065 mg / kg, about 0.070 mg / kg, about 0.075 mg / kg, about 0.080 mg / kg, about 0.085 mg / kg, about 0.090 mg / kg, about 0.095 mg / kg, or about 0.100 mg / kg. In some embodiments, tacrolimus may be administered to the subject about three weeks before (e.g., approximately 21 days before) the administration of the composition comprising PRP cells at a daily dose of about 0.075 mg / kg. In some embodiments, tacrolimus may be administered to the subject about two weeks before (e.g., approximately 14 days before) the administration of the composition comprising PRP cells at a daily dose of about 0.075 mg / kg.

[0218] In some embodiments, tacrolimus may be administered to the subject to maintain trough levels between about 2 and about 12 ng / mL. In some embodiments, tacrolimus may be administered to the subject to maintain trough levels of about 2 ng / mL, about 3 ng / mL, about 4 ng / mL, about 5 ng / mL, about 6 ng / mL, about 7 ng / mL, about 8 ng / mL, about 9 ng / mL, about 10 ng / mL, about 11 ng / mL, or about 12 ng / mL. In some embodiments, tacrolimus may be administered to the subject to maintain trough levels between about 2 ng / mL to about 8 ng / mL, about 3 ng / mL to about 9 ng / mL, about 4 ng / mL to about 10 ng / mL, about 5 ng / mL to about 11 ng / mL, about 6 ng / mL to about 12 ng / mL, about 2 ng / mL to about 7 ng / mL, about 3 ng / mL to about 8 ng / mL, about 4 ng / mL to about 9 ng / mL, about 5 ng / mL to about 10 ng / mL, about 6 ng / mL to about 11 ng / mL, about 7 ng / mL to about 12 ng / mL, about 2 ng / mL to about 6 ng / mL, about 3 ng / mL to about 7 ng / mL, about 4 ng / mL to about 8 ng / mL, about 5 ng / mL to about 9 ng / mL, about 6 ng / mL to about 10 ng / mL, about 7 ng / mL to about 11 ng / mL, about 8 ng / mL to about 12 ng / mL,Attorney Docket No.: 132042-5007-WOabout 2 ng / mL to about 5 ng / mL, about 3 ng / mL to about 6 ng / mL, about 4 ng / mL to about 7 ng / mL, about 5 ng / mL to about 8 ng / mL, about 6 ng / mL to about 9 ng / mL, about 7 ng / mL to about 10 ng / mL, about 8 ng / mL to about 11 ng / mL, about 9 ng / mL to about 12 ng / mL, about 2 ng / mL to about 4 ng / mL, about 3 ng / mL to about 5 ng / mL, about 4 ng / mL to about 6 ng / mL, about 5 ng / mL to about 7 ng / mL, about 6 ng / mL to about 8 ng / mL, about 7 ng / mL to about 9 ng / mL, about 8 ng / mL to about 10 ng / mL, about 9 ng / mL to about 11 ng / mL, or about 10 ng / mL to about 12 ng / mL. In some embodiments, tacrolimus may be administered to the subject to maintain trough levels between about 6 ng / mL to about 10 ng / mL. In some embodiments, tacrolimus may be administered to the subject to maintain trough levels between about 6 ng / mL to about 12 ng / mL. In some embodiments, tacrolimus may be administered to the subject to maintain trough levels between about 4 ng / mL to about 10 ng / mL. In some embodiments, tacrolimus may be administered to the subject to maintain trough levels between about 4 ng / mL to about 12 ng / mL. In some embodiments, tacrolimus trough levels will be monitored via blood sampling prior to and / or after administration of the composition comprising PRP cells.

[0219] In some embodiments, tacrolimus may be discontinued about 1 week to about 70 weeks after the delivery of the composition comprising PRP cells. In some embodiments, tacrolimus may be discontinued about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, about 15, about 16, about 17, about 18, about 19, about 20, about 21, about 22, about 23, about 24, about 25, about 26, about 27, about 28, about 29, about 30, about 31, about 32, about 33, about 34, about 35, about 36, about 37, about 38, about 39, about 40, about 41, about 42, about 43, about 44, about 45, about 46, about 47, about 48, about 49, about 50, about 51, about 52, about 53, about 54, about 55, about 56, about 57, about 58, about 59, about 60, about 61, about 62, about 63, about 64, about 65, about 66, about 67, about 68, about 69, or about 70 weeks after the delivery of the composition comprising PRP cells. In some embodiments, tacrolimus may be discontinued 52 weeks after the delivery of the composition comprising PRP cells.

[0220] In some embodiments, MPA may be administered about one to about three weeks before administration of the composition comprising PRP cells at a daily dose of about 500 mg to about 900 mg twice daily. In some embodiments, MPA may be administered about one, about two, or about three weeks before administration of the composition comprising PRP cells. In some embodiments, MPA may be administered at a daily dose of about 500 mg, about 510 mg, about 520 mg, about 530 mg, about 540 mg, about 550 mg, about 560 mg, about 570 mg, about 580 mg, about 590 mg, about 600 mg, about 610 mg, about 620 mg, about 630 mg, about 640 mg,Attorney Docket No.: 132042-5007-WOabout 650 mg, about 660 mg, about 670 mg, about 680 mg, about 690 mg, about 700 mg, about 710 mg, about 720 mg, about 730 mg, about 740 mg, about 750 mg, about 760 mg, about 770 mg, about 780 mg, about 790 mg, about 800 mg, about 810 mg, about 820 mg, about 830 mg, about 840 mg, about 850 mg, about 860 mg, about 870 mg, about 880 mg, about 890 mg, or about 900 mg twice daily. In some embodiments, MPA may be administered about two weeks before (e.g., approximately 14 days before) administration of the composition comprising PRP cells at a daily dose of about 720 mg twice daily.

[0221] In some embodiments, MPA may be discontinued about 1 week to about 70 weeks after the delivery of the composition comprising PRP cells. In some embodiments, MPA may be discontinued about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, about 15, about 16, about 17, about 18, about 19, about 20, about 21, about 22, about 23, about 24, about 25, about 26, about 27, about 28, about 29, about 30, about 31, about 32, about 33, about 34, about 35, about 36, about 37, about 38, about 39, about 40, about 41, about 42, about 43, about 44, about 45, about 46, about 47, about 48, about 49, about 50, about 51, about 52, about 53, about 54, about 55, about 56, about 57, about 58, about 59, about 60, about 61, about 62, about 63, about 64, about 65, about 66, about 67, about 68, about 69, or about 70 weeks after the delivery of the composition comprising PRP cells. In some embodiments, MPA may be discontinued 52 weeks after the delivery of the composition comprising PRP cells.

[0222] In some embodiments, the subject may receive systemic (e.g., oral prednisone) and local (e.g., dexamethasone intravitreal implant and / or topical difluprednate drops) corticosteroids. In some embodiments, an oral corticosteroid regimen may begin prior to administration of the composition comprising PRP cells, and topical corticosteroids may begin the same day or the day following administration. In some embodiments, both types of corticosteroids may be tapered over the weeks following surgery.

[0223] In some embodiments, the subject may receive oral prednisone about one day to about fourteen days before administration of the composition comprising PRP cells at a daily starting dose of about 0.1 mg / kg to about 2 mg / kg, but not to exceed 80 mg. In some embodiments, the subject may receive oral prednisone about one, about two, about three, about four, about five, about six, about seven, about eight, about nine, about ten, about eleven, about twelve, about thirteen, or about fourteen days before administration of the composition comprising PRP cells. In some embodiments, the subject may receive oral prednisone at a daily starting dose of about 0.1 mg / kg, about 0.2 mg / kg, about 0.3 mg / kg, about 0.4 mg / kg, about 0.5 mg / kg, about 0.6 mg / kg,Attorney Docket No.: 132042-5007-WOabout 0.7 mg / kg, about 0.8 mg / kg, about 0.9 mg / kg, about 1.0 mg / kg, about 1.1 mg / kg, about 1.2 mg / kg, about 1.3 mg / kg, about 1.4 mg / kg, about 1.5 mg / kg, about 1.6 mg / kg, about 1.7 mg / kg, about 1.8 mg / kg, about 1.9 mg / kg, or about 2.0 mg / kg, but not to exceed 80 mg. In some embodiments, the subject may receive oral prednisone about one week (e.g., approximately seven days) before administration of the composition comprising PRP cells at a daily starting dose of 1 mg / kg, but not to exceed 80 mg. In some embodiments, when the subject weighs more than 100 kg, the dose of oral prednisone may exceed 80 mg.

[0224] In some embodiments, the subject may receive oral prednisone about one day to about fourteen days before administration of the composition comprising PRP cells at a daily starting dose of about 0.1 mg / kg to about 2 mg / kg, only to exceed 80 mg when the subject weighs more than 100 kg. In some embodiments, the subject may receive oral prednisone about one, about two, about three, about four, about five, about six, about seven, about eight, about nine, about ten, about eleven, about twelve, about thirteen, or about fourteen days before administration of the composition comprising PRP cells. In some embodiments, the subject may receive oral prednisone at a daily starting dose of about 0.1 mg / kg, about 0.2 mg / kg, about 0.3 mg / kg, about 0.4 mg / kg, about 0.5 mg / kg, about 0.6 mg / kg, about 0.7 mg / kg, about 0.8 mg / kg, about 0.9 mg / kg, about 1.0 mg / kg, about 1.1 mg / kg, about 1.2 mg / kg, about 1.3 mg / kg, about 1.4 mg / kg, about 1.5 mg / kg, about 1.6 mg / kg, about 1.7 mg / kg, about 1.8 mg / kg, about 1.9 mg / kg, or about 2.0 mg / kg, only to exceed 80 mg when the subject weighs more than 100 kg. In some embodiments, the subject may receive oral prednisone about one week (e.g., approximately seven days) before administration of the composition comprising PRP cells at a daily starting dose of 1 mg / kg, only to exceed 80 mg when the subject weighs more than 100 kg.

[0225] In some embodiments, the starting dose of prednisone may be continued for six days after administration of the composition comprising PRP cells and then tapered over approximately six weeks. In some embodiments, the starting dose of prednisone may be continued for about one, about two, about three, about four, about five, about six, about seven, about eight, about nine, about ten, about eleven, about twelve, about thirteen, or about fourteen days after administration. In some embodiments, the dose may be tapered as shown in Table 3.Table 3. Oral Prednisone TaperDay after PRPPrednisone daily dosecell deliveryStarting Dose 1 mg / kg (maximum 80 mg)Day 7 Starting dosex0.83Attorney Docket No.: 132042-5007-WODay after PRPPrednisone daily dosecell deliveryDay 14 Starting dosex0.67Day 21 Starting dosex0.5Day 28 Starting dosex0.33Day 35 Starting dosex0.17Day 42 Starting dosex0.08Day 48 Stop

[0226] In some embodiments, the oral prednisone may be terminated after about 1 to about 70 days after administration of the composition comprising PRP cells. In some embodiments, the oral prednisone may be terminated after about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, about 15, about 16, about 17, about 18, about 19, about 20, about 21, about 22, about 23, about 24, about 25, about 26, about 27, about 28, about 29, about 30, about 31, about 32, about 33, about 34, about 35, about 36, about 37, about 38, about 39, about 40, about 41, about 42, about 43, about 44, about 45, about 46, about 47, about 48, about 49, about 50, about 51, about 52, about 53, about 54, about 55, about 56, about 57, about 58, about 59, about 60, about 61, about 62, about 63, about 64, about 65, about 66, about 67, about 68, about 69, or about 70 days. In some embodiments, the oral prednisone may be terminated after 48 days after administration of the composition comprising PRP cells. In some embodiments, the doses may be rounded to the nearest 5 mg to facilitate optimal dosage form availability. In some embodiments, adjustments resulting in a slower taper may be made.

[0227] In some embodiments, the subject may receive an intravitreal corticosteroid implant such as Ozurdex® (e.g., a dexamethasone intravitreal implant). This implant provides a means of administering corticosteroids close to the site of administration in a sustained-release fashion for up to about three months. The implant may be placed into the vitreous cavity after delivery of the composition comprising PRP cells, whereupon it dissolves without requiring subsequent removal.

[0228] In some embodiments, a dexamethasone intravitreal implant may be administered intraoperatively on the same day as administration of the composition comprising PRP cells at a dose of about 0.1 mg to about 1.5 mg. In some embodiments, the dexamethasone intravitreal implant may be administered intraoperatively on the same day as administration of the composition comprising PRP cells at a dose of about 0.1 mg, about 0.2 mg, about 0.3 mg, about 0.4 mg, about 0.5 mg, about 0.6 mg, about 0.7 mg, about 0.8 mg, about 0.9 mg, about 1.0 mg, about 1.1 mg, about 1.2 mg, about 1.3 mg, about 1.4 mg, or about 1.5 mg. In some embodiments, a dexamethasone intravitreal implant may be administered intraoperatively on the same day as administration of the composition comprising PRP cells at a dose of about 0.7 mg. In someAttorney Docket No.: 132042-5007-WOembodiments, a subject may receive an additional dexamethasone intravitreal implant at a later timepoint. In some embodiments, a subject may receive multiple additional dexamethasone intravitreal implants at later timepoints.

[0229] In other embodiments, the subject may receive difluprednate drops at a concentration of about 0.01% to about 0.10% starting on the same day as administration of the composition comprising PRP cells. In other embodiments, the subject may receive difluprednate drops at a concentration of about 0.01% to about 0.10% starting on the day following administration of the composition comprising PRP cells. In other embodiments, the subject may optionally receive difluprednate drops at a concentration of about 0.01%, about 0.02%, about 0.03%, about 0.04%, about 0.05%, about 0.06%, about 0.07%, about 0.08%, about 0.09%, or about 0.10%. In other embodiments, the subject optionally may receive difluprednate drops at a concentration of 0.05% starting on the same day as administration of the composition comprising PRP cells. In other embodiments, the subject optionally may receive difluprednate drops at a concentration of 0.05% starting on the day following administration of the composition comprising PRP cells.

[0230] In some embodiments, the difluprednate drops may be administered between one and eight times daily into the same eye as the composition comprising PRP cells was administered to the subject. In some embodiments, the difluprednate drops may be administered about one, about two, about three, about four, about five, about six, about seven, or about eight times daily into the same eye as the composition comprising PRP cells was administered to the subject. In some embodiments, the difluprednate drops may be administered about four times daily into the same eye as the composition comprising PRP cells was administered to the subject.

[0231] In some embodiments, after the administration of the composition comprising PRP cells, the difluprednate drops may be tapered overtime. In some embodiments, the difluprednate drops may be terminated after about 1 day to about 70 days after administration of the composition comprising PRP cells. In some embodiments, the difluprednate drops may be terminated after about 1, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 11, about 12, about 13, about 14, about 15, about 16, about 17, about 18, about 19, about 20, about 21, about 22, about 23, about 24, about 25, about 26, about 27, about 28, about 29, about 30, about 31, about 32, about 33, about 34, about 35, about 36, about 37, about 38, about 39, about 40, about 41, about 42, about 43, about 44, about 45, about 46, about 47, about 48, about 49, about 50, about 51, about 52, about 53, about 54, about 55, about 56, about 57, about 58, about 59, about 60, about 61, about 62, about 63, about 64, about 65, about 66, about 67, about 68, about 69, or about 70 days after administration of the composition comprising PRP cells. InAttorney Docket No.: 132042-5007-WOsome embodiments, the difluprednate drops may be terminated after about 29 days after administration of the composition comprising PRP cells. In some embodiments, the dose may be tapered as shown in Table 4.Table 4. Difluprednate Drops TaperDay after PRP cell delivery Difluprednate daily doseDay 1 (Starting Dose) 1 drop in eye 4x / dayDay 8 1 drop in eye 3x / dayDay 15 1 drop in eye 2x / dayDay 22 1 drop in eye 1x / dayDay 29Stop

[0232] In some embodiments, basiliximab may optionally be used to prevent cell graft rejection by the subject’s immune system. In some embodiments, basiliximab may be administered as an infusion at a dose of about 1 mg to about 40 mg. In some embodiments, basiliximab may be administered as an infusion at a dose of about 1 mg, about 2 mg, about 3 mg, about 4 mg, about 5 mg, about 6 mg, about 7 mg, about 8 mg, about 9 mg, about 10 mg, about 11 mg, about 12 mg, about 13 mg, about 14 mg, about 15 mg, about 16 mg, about 17 mg, about 18 mg, about 19 mg, about 20 mg, about 21 mg, about 22 mg, about 23 mg, about 24 mg, about 25 mg, about 26 mg, about 27 mg, about 28 mg, about 29 mg, about 30 mg, about 31 mg, about 32 mg, about 33 mg, about 34 mg, about 35 mg, about 36 mg, about 37 mg, about 38 mg, about 39 mg, or about 40 mg. In some embodiments, basiliximab may be administered as an infusion at a dose of about 20 mg. In some embodiments, the basiliximab may be administered on one occasion after surgery. In other embodiments, basiliximab may be administered on two occasions after surgery. In some embodiments, basiliximab may be administered at a first time within about 24 hours after surgery and at a second time about three to about four days after surgery.

[0233] In some embodiments, the subject may receive an intravenous antibiotic prior to administration of the composition comprising PRP cells. The intravenous antibiotic may be cefazolin and / or vancomycin. The antibiotics may prevent bacterial infection of the eye before, during, or after the surgical administration of the composition comprising PRP cells. In some embodiments, vancomycin may be used to prevent infection in subjects.

[0234] In some embodiments, the subject may be administered intravenous cefazolin at a dose of about 0.1 g to about 4.0 g prior to the surgical administration of the composition comprising PRP cells including to prevent infection. In some embodiments, the subject may be administered intravenous cefazolin at a dose of about 0.1 g, about 0.2 g, about 0.3 g, about 0.4 g, about 0.5 g, about 0.6 g, about 0.7 g, about 0.8 g, about 0.9 g, about 1.0 g, about 1.1 g, about 1.2 g, about 1.3Attorney Docket No.: 132042-5007-WOg, about 1.4 g, about 1.5 g, about 1.6 g, about 1.7, about 1.8 g, about 1.9 g, about 2.0 g, about 2.1 g, about 2.2 g, about 2.3 g, about 2.4 g, about 2.5 g, about 2.6 g, about 2.7 g, about 2.8 g, about 2.9 g, about 3.0 g, about 3.1 g, about 3.2 g, about 3.3 g, about 3.4 g, about 3.5 g, about 3.6 g, about 3.7 g, about 3.8 g, about 3.9 g, or about 4.0 g prior to the surgical administration of the composition comprising PRP cells. In some embodiments, the subject may be administered intravenous cefazolin at a dose of about 2.0 g prior to the surgical administration of the composition comprising PRP cells to prevent infection. In some embodiments, the subject may be administered intravenous cefazolin at a dose of about 3.0 g of cefazolin prior to the surgical administration of the composition comprising PRP cells. In some embodiments, the intravenous cefazolin may be administered to the subject about 10 minutes to about 120 minutes prior to the surgical administration of the composition comprising PRP cells. In some embodiments, the intravenous cefazolin may be administered to the subject about 10, about 20, about 30, about 40, about 50, about 60, about 70, about 80, about 90, about 100, about 110, or about 120 minutes prior to the surgical administration of the composition comprising PRP cells. In some embodiments, the intravenous cefazolin may be administered to the subject about 60 minutes prior to the surgical administration of the composition comprising PRP cells.

[0235] In some embodiments, the subject may be administered vancomycin at a dose of about 8 mg / kg to about 22 mg / kg prior to the surgical administration of the composition comprising PRP cells. In some embodiments, the subject may be administered vancomycin at a dose of about 8 mg / kg, about 9 mg / kg, about 10 mg / kg, about 11 mg / kg, about 12 mg / kg, about 13 mg / kg, about 14 mg / kg, about 15 mg / kg, about 16 mg / kg, about 17 mg / kg, about 18 mg / kg, about 19 mg / kg, about 20 mg / kg, about 21 mg / kg, or about 22 mg / kg prior to the surgical administration of the composition comprising PRP cells. In some embodiments, the subject may be administered vancomycin at a dose of about 15 mg / kg prior to the surgical administration of the composition comprising PRP. In some embodiments, the vancomycin may be administered to the subject about 10 minutes to about 120 minutes prior to the surgical administration of the composition comprising PRP cells. In some embodiments, the vancomycin may be administered to the subject about 10, about 20, about 30, about 40, about 50, about 60, about 70, about 80, about 90, about 100, about 110, or about 120 minutes prior to the surgical administration of the composition comprising PRP cells. In some embodiments, the vancomycin may be administered to the subject about 60 minutes prior to the surgical administration of the composition comprising PRP cells.

[0236] In some embodiments, the subject will be assessed for the presence of antiphotoreceptor precursor cell HLA antibodies at screening. In alternative embodiments, the subjectAttorney Docket No.: 132042-5007-WOwill not be assessed for the presence of anti-photoreceptor precursor cell HLA antibodies at screening. In some embodiments, anti-photoreceptor precursor cell HLA antibody testing at screening is optional. In some embodiments, the subject will not be treated with and / or administered the composition comprising PRP cells if the subject expresses anti-photoreceptor precursor cell HLA antibodies at screening. In some embodiments, the subject will not be treated with and / or administered the composition comprising PRP cells if the subject expresses antiphotoreceptor precursor cell HLA-C antibodies at screening. In some embodiments, the subject will not be treated with and / or administered the composition comprising PRP cells if the subject expresses anti-photoreceptor precursor cell HLA-DR antibodies at screening. In some embodiments, the subject will not be treated with and / or administered the composition comprising PRP cells if the subject expresses anti-photoreceptor precursor cell HLA-DPB1 antibodies at screening. In some embodiments, the subject will not be treated with and / or administered the composition comprising PRP cells if the subject expresses one or more of anti-photoreceptor precursor cell HLA-C, HLA-DR, and / or HLA-DPB1 antibodies at screening.Assessments of Improvement in Vision

[0237] A subject administered a composition comprising PRP cells may be subjected to one or more ophthalmic, visual function, functional vision, and / or retinal imaging assessments to determine if the treatment improved their vision. In some embodiments, these assessments are performed in the same eye to which the composition comprising PRP cells were administered. In some embodiments, the assessments may be performed in both eyes.

[0238] In some embodiments, a patient-reported outcome may be assessed. In some embodiments, the Michigan Retinal Degeneration Questionnaire (MRDQ) and the Michigan Vision-related Anxiety Questionnaire (MVAQ) may be administered. The MRDQ is a psychometrical ly validated measure for subjects with inherited retinal degenerations. The 59-item questionnaire encompasses seven domains representative of physiological visual function pathways: central vision, color vision, contrast sensitivity, scotopic function, photopic peripheral vision, mesopic peripheral vision, and photosensitivity. The MVAQ is a psychometrically validated fourteen-item psychosocial screening and monitoring tool used for subjects with inherited retinal degenerations. In some embodiments, subjects may complete the questionnaires at a respective visit before any visual function testing may be conducted. In some embodiments, the subject may complete the questionnaires before (e.g., baseline) and after administration of the composition comprising PRP cells. In some embodiments, the patient-reported outcome may be considered improved if a change from baseline is observed after administration of the composition comprisingAttorney Docket No.: 132042-5007-WOPRP cells as measured by the Michigan Retinal Degeneration Questionnaire (MRDQ) and the Michigan Vision-related Anxiety Questionnaire (MVAQ).

[0239] In some embodiments, visual function of the subject may be assessed to measure how well the eye and visual system function. Low-luminance visual acuity (LLVA) and best corrected visual acuity (BCVA) may be assessed in each eye using the Early Treatment of Diabetic Retinopathy Study (ETDRS) and / or the Berkeley Rudimentary Vision Test (BRVT) charts before and after administration of the composition comprising PRP cells to evaluate visual acuity (VA) changes. LLVA and BCVA are measures of the ability to distinguish shapes and details of images at a set distance. Both of these tests of visual function are a measure of cone cell function and foveal and / or macular health. In some embodiments, subjective refraction, LLVA, and / or BCVA may be performed before pupil dilation or anesthetic eye drops or other ocular manipulation that may interfere with VA assessment. If the LLVA and BCVA are performed on the same day, the LLVA may be performed before BCVA testing.

[0240] In some embodiments, the logarithm of the Minimum Angle of Resolution (LogMAR) value may be reported for subjects before or after the administration of the composition comprising PRP cells. The Minimum Angle of Resolution may be measured as one fifth of the height of the optotype, expressed in minutes of arc. In some embodiments, an ETDRS letter score of about 85 corresponds to a LogMAR value of about 0.0. In some embodiments, an ETDRS letter score of about 60 corresponds to a LogMAR value of about 0.5. In some embodiments, an ETDRS letter score of about 35 corresponds to a LogMAR value of about 1.0. In some embodiments, an ETDRS letter score of about 10 corresponds to a LogMAR value of about 1.5. In the event that a subject is unable to read letters on the ETDRS chart in either eye, the BRVT chart may be used to quantify a LogMAR value to measure visual acuity. In some embodiments, the visual acuity measured by a single tumbling E test corresponds to a LogMAR value of between about 2.0 to about 2.5. In some embodiments, the visual acuity measured by a black and white discrimination test corresponds to a LogMAR value of about 3.0. In some embodiments, the visual acuity measured by a light perception test corresponds to a LogMAR value of about 3.9.

[0241] In some embodiments, LLVA and BCVA may be reported as the calculated ETDRS letter score (if applicable) and the corresponding LogMAR value in each eye or in the study eye only. If a subject is unable to read letters on the ETDRS chart in either eye and their acuity is found to be count fingers (CF), hand motion (HM), or light perception (LP), their vision in the respective eye may also be tested using the BRVT chart and reported using a LogMAR value in addition to their original result (e.g., CF, HM, or LP). In some embodiments, the BRVT chart includes various tests,Attorney Docket No.: 132042-5007-WCfor example, single tumbling E, black and white discrimination, and light perception or no light perception. In some embodiments, the ETDRS and BRVT charts provide quantifiable vision impairment levels across the spectrum of visual function through the use of the LogMAR value.

[0242] In some embodiments, a subject at baseline (e.g., before the administration of the composition comprising PRP cells) may have a BCVA of LogMAR of 0.5 of higher (e.g., 0.5 or higher, 1.0 or higher, or 1.3 or higher) in the study eye. In some embodiments, a subject may have at baseline a BCVA LogMAR 3.9-1.3 (e.g., 3.9-1.3, 2.9-1.0, or 1.3-0.5) in the study eye. In some embodiments, a subject has at baseline an ETDRS score of 60 or less (e.g., 60 or less, 35 or less, or 20 or less) in the study eye. In some embodiments, a subject at baseline has a LogMAR that cannot be appropriately determined with an ETDRS test and / or chart, and requires other tests (e.g., a BRVT) that are better suited for assessing relatively worse visual acuity. In some embodiments, a subject may have a BCVA at baseline between about LogMAR 3.9 to about LogMAR 0.5 in the study eye. In some embodiments, a subject may have an ETDRS letter score at baseline between about 20 and about 60 in the study eye. In some embodiments, a subject has a BCVA at baseline between about LogMAR 3.9 to about LogMAR 1.3 in the study eye. In some embodiments, a subject has at baseline an ETDRS letter score of about 20 or less in the study eye. In some embodiments, a subject has a BCVA at baseline between about LogMAR 3.9 to about LogMAR 1.3 in the study eye and / or an ETDRS letter score of about 20 or less in the study eye. In some embodiments, a subject has a BCVA at baseline between about LogMAR 2.9 to about LogMAR 1.0 in the study eye. In some embodiments, a subject has at baseline an ETDRS letter score of about 30 or less in the study eye. In some embodiments, a subject has a BCVA at baseline between about LogMAR 2.9 to about LogMAR 1.0 in the study eye and / or an ETDRS letter score of about 30 or less in the study eye. In some embodiments, a subject has a BCVA at baseline between about LogMAR 1.3 to about LogMAR 0.5 in the study eye. In some embodiments, a subject has at baseline an ETDRS letter score between about 20 and about 60 in the study eye. In some embodiments, a subject has a BCVA at baseline between about LogMAR 1.3 to about LogMAR 0.5 in the study eye and / or an ETDRS letter score between about 20 and about 60 in the study eye.

[0243] LLVA may be measured by placing a 2.0-log unit neutral density filter over the front of each eye. To establish an accurate baseline LLVA as well as ensure that the subject can perform the LLVA assessment in a reliable manner, LLVA may be performed at least three times in each eye, across at least two separate days during the screening. In some embodiments, two of theAttorney Docket No.: 132042-5007-WOtests may be performed on the first day and one test may be performed on the second day for each eye.

[0244] In some embodiments, full-field stimulus testing (FST) may be performed in each eye using multiple colors and wavelength to evaluate light sensitivity. In some embodiments, the subject may be assessed for light sensitivity before (e.g., baseline) and after administration of the composition comprising PRP cells by FST. In some embodiments, the light sensitivity may be considered improved if a change from baseline is observed after administration of the composition comprising PRP cells as indicated by a positive change in light sensitivity as measured by FST. In some embodiments, FST is performed before or after pupil dilation. In some embodiments, FST is performed after pupil dilation.

[0245] In some embodiments, the subject may be assessed for LLVA and BCVA before (e.g., baseline) and after administration of the composition comprising PRP cells. In some embodiments, the visual function may be considered improved if a change from baseline is observed after administration of the composition comprising PRP cells as indicated by an improvement in BCVA of about 0.3 or more LogMAR units (e.g., about 15 or higher ETDRS letter score) and / or an improvement in LLVA of about 0.3 or more LogMAR units (e.g., about 15 or higher ETDRS letter score). In some embodiments, a subject may have a BCVA at baseline between about LogMAR 3.9 to about LogMAR 1.0 in the study eye. In some embodiments, a subject may have an ETDRS letter score at baseline between about 20 and about 60 in the study eye. In some embodiments, a subject may have a BCVA at baseline between about LogMAR 3.9 to about LogMAR 0.5 in the study eye. In some embodiments, a subject may have an ETDRS letter score at baseline between about 20 and about 60 in the study eye.

[0246] In some embodiments, visual function, and retinal sensitivity after administration of the composition comprising PRP cells may be assessed in each eye using macular integrity assessment (MAIA) microperimetry (MP). Micro perimetry is a type of visual field test that measures sensitivity to light in the central retina in pre-defined locations. MP allows assessments of sensitivity in both rods and cones and may be measured in decibels. Lower decibels (e.g., about 0 dB) indicate low or no vision, whereas higher decibels (e.g., about 36 dB) indicates better vision and light sensitivity. During screening, MP may be performed twice in each eye and may be performed over two or more days. In some embodiments, a third attempt may be performed. A mean retinal sensitivity may be calculated based on multiple MP readings. In some embodiments, the subject may be assessed for retinal sensitivity before (e.g., baseline) and after administration of the composition comprising PRP cells. In some embodiments, the retinalAttorney Docket No.: 132042-5007-WOsensitivity may be considered improved if a change from baseline is observed after administration of the composition comprising PRP cells as indicated by an improvement in mean retinal sensitivity of seven or more decibels in the region of administration of the composition comprising PRP cells.

[0247] In some embodiments, retinal sensitivity after administration of the composition comprising PRP cells may be assessed in each eye using static perimetry in both eyes by certified technicians using an Octopus 900 perimeter (Haag-Streit AG, Switzerland). In some embodiments, static perimetry may be performed twice in each eye and may be performed over at least two days prior to administration of the composition comprising PRP cells. In some embodiments, a third attempt may be performed. In some embodiments, static perimetry is performed before or after pupil dilation. In some embodiments, static perimetry is performed after pupil dilation. In some embodiments, dark-adapted static perimetry may also be performed in both eyes. In some embodiments, dark-adapted static perimetry is performed before or after pupil dilation. In some embodiments, dark-adapted static perimetry is performed after pupil dilation. In some embodiments, the subject may be assessed for retinal sensitivity before (e.g., baseline) and after administration of the composition comprising PRP cells. In some embodiments, the retinal sensitivity may be considered improved if a change from baseline is observed after administration of the composition comprising PRP cells as indicated by a positive change in mean retinal sensitivity in the region of administration of the composition comprising PRP cells.

[0248] In some embodiments, a color vision test may be performed to determine if the treatment improved their vision. In some embodiments, color vision may be assessed in both eyes using the Hardy Rand and Rittler (HRR) pseudoisochromatic test. In some embodiments, the subject may be assessed by color vision test before (e.g., baseline) and after administration of the composition comprising PRP cells. In some embodiments, the color vision may be considered improved if a change from baseline is observed after administration of the composition comprising PRP cells as indicated by a better performance on the HRR pseudoisochromatic test.

[0249] In some embodiments, retinal imaging may be performed in both eyes before and after administration of the composition comprising PRP cells to determine if the treatment improved their vision. In some embodiments, retinal imaging may include spectral domain optical coherence tomography (SD-OCT), fundus autofluorescence (FAF), and / or color fundus photography (CFP). OCT is a non-invasive imaging technique that provides a cross-sectional view of the retina, allowing measurement of the outer nuclear layer thickness. FAF is a non-invasive imagingAttorney Docket No.: 132042-5007-WOtechnique of the retina that utilizes the fluorescent properties of lipofuscin within the retinal pigment epithelium (RPE) to create and image.

[0250] In some embodiments, functional vision may be assessed to measure how well a person performs a visual task and evaluate the impact of visual impairment in daily life activities. In some embodiments, the ability of a subject to navigate their environment under different lighting conditions after administration of the composition comprising PRP cells may be assessed using the Ora Visual Navigation Course (Ora-VNC™; Ora, Inc., Andover, MA). In some embodiments, a multi-luminance navigation test (MLNT) may be performed to assess functional vision. The MLNT is a standardized, lab-based test where the subject navigated a course with obstacles under different illumination levels. In some embodiments, the MLNT may be performed using each eye separately as well as using both eyes together. In some embodiments, the subject may be assessed for functional vision before (e.g., baseline) and after administration of the composition comprising PRP cells. In some embodiments, the functional vision may be considered improved if a reduction of two or more illumination levels from baseline is observed after administration of the composition comprising PRP cells as indicated by the MLNT.

[0251] In some embodiments, the subject may be screened prior to administration of the composition comprising PRP cells. The subject may be screened using LLVA, BCVA, MP, SD-OCT, FAF, CFP, fluorescein angiography (FA), FST, color vision test, ophthalmic evaluation, urinalysis, MLNT, static perimetry, and / or dark-adapted perimetry. In some embodiments, FST, FA, static perimetry, and / or dark-adapted perimetry are performed after pupil dilation. In some embodiments, the subject may be screened for genetic confirmation of primary photoreceptor disease, pregnancy, blood serology, hematology, anti-PRP cell antibodies, biomarkers, clinical chemistry, coagulation and / or human leukocyte antigen (HLA) typing. In some embodiments, the subject may be screened no more than seventy days before administration of the composition comprising PRP cells.Illustration of Subject Technology as Clauses

[0252] Various examples of aspects are described as numbered clauses (1, 2, 3, etc.) for convenience. These are provided as examples, and do not limit the subject technology. Identifications of the figures and reference numbers are provided below merely as examples and for illustrative purposes, and the clauses are not limited by those identifications.Attorney Docket No.: 132042-5007-WO

[0253] Clause 1: A method of treating an inherited retinal disease in a subject in need thereof, the method comprising: administering a therapeutically effective amount of a composition comprising photoreceptor precursor cells to an eye of the subject in need thereof.

[0254] Clause 2: The method of clause 1, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is surgically administered to the eye of the subject.

[0255] Clause 3: The method of clause 1 or 2, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is surgically administered into a subretinal space of the eye of the subject.

[0256] Clause 4: The method of any one of clauses 1-3, wherein a subretinal injection that comprises the therapeutically effective amount of the composition comprising photoreceptor precursor cells is surgically administered into the subretinal space of the eye of the subject.

[0257] Clause 5: The method of any one of clauses 1-4, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered as a single dose.

[0258] Clause 6: The method of any one of clauses 1-5, wherein the subject is a human.

[0259] Clause 7: The method of clause 6, wherein the human is at least 18 years of age.

[0260] Clause 8: The method of any one of clauses 1-7, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells includes between about 0.5x106to about 5.0x106photoreceptor precursor cells.

[0261] Clause 9: The method of any one of clauses 1-8, wherein the subject is administered one or more immunosuppressive agents beginning about two to three weeks prior to administration of the therapeutically effective amount of the composition comprising photoreceptor precursor cells.

[0262] Clause 10: The method of clause 9, wherein one or more immunosuppressive agents are selected from the group consisting of: tacrolimus, mycophenolic acid, prednisone, locally administered dexamethasone, and difluprednate.

[0263] Clause 11: The method of clause 10, wherein one or more immunosuppressive agents are administered to the subject for about fifty-two weeks after the administration of the therapeutically effective amount of photoreceptor precursor cells.Attorney Docket No.: 132042-5007-WO

[0264] Clause 12: The method of any one of clauses 1-11, wherein the composition comprising photoreceptor precursor cells includes rod cells and / or cone cells.

[0265] Clause 13: The method of any one of clauses 1-12, wherein the photoreceptor precursor cells are derived from human induced pluripotent stem cells.

[0266] Clause 14: The method of any one of clauses 1-13, wherein the photoreceptor precursor cells are allogeneic.

[0267] Clause 15: The method of any one of clauses 1-14, wherein the inherited retinal disease affects a function and / or structure of a retina in the eye of the subject.

[0268] Clause 16: The method of any one of clauses 1-15, wherein the inherited retinal disease is a primary photoreceptor disease.

[0269] Clause 17: The method of clause 16, wherein the primary photoreceptor disease is selected from the group consisting of: retinitis pigmentosa, Usher Syndrome, cone-rod disease, rod-cone disease, cone dystrophy, and cone-rod dystrophy.

[0270] Clause 18: The method of any one of clauses 1-17, wherein the subject has diminished vision due to cellular loss of rod cells and / or cone cells.

[0271] Clause 19: The method of any one of clauses 1-18, wherein the method of treating results in a change in retinal structure in the eye in the subject.

[0272] Clause 20: The method of clause 19, wherein the change in retinal structure is an increase in thickness of an outer retinal layer.

[0273] Clause 21: The method of clause 20, wherein the thickness of the outer retinal layer is measured by spectral domain optical coherence tomography or by fundus autofluorescence.

[0274] Clause 22: The method of any one of clauses 1-21, wherein the photoreceptor precursor cells differentiate and / or mature into cells that exhibit one or more of the following properties: form inner segments, form outer segments, express opsin, or traffic rhodopsin to outer segments by rods.

[0275] Clause 23: The method of any one of clauses 1-22, wherein the method of treating leads to reformation of an outer nuclear layer.

[0276] Clause 24: The method of any one of clauses 1-23, wherein the method of treating improves visual function and / or functional vision in the subject, wherein the subject is human.Attorney Docket No.: 132042-5007-WO

[0277] Clause 25: The method of clause 24, wherein visual function and / or functional vision is improved where, as compared to baseline, the subject exhibits one or more of: a mean retinal sensitivity greater than or equal to seven decibels as measured by micro perimetry, light sensitivity improvement as measured by full-field stimulus testing, a clinically significant improvement in retinal sensitivity as measured by static perimetry, a best corrected visual acuity (BCVA) greater than or equal to 0.3 Logarithm of the Minimum Angle of Resolution (Log AR) units and > 15 Early Treatment of Diabetic Retinopathy Study (ETDRS) letter score, optionally wherein the human has a BCVA at baseline between LogMAR 3.9 to LogMAR 0.5 in a study eye and / or has an ETDRS letter score at baseline of 60 or less in the study eye, a low luminance visual acuity (LLVA) greater than or equal to 0.3 LogMAR units and > 15 ETDRS letter score, a clinically significant improvement in retinal sensitivity as measured by dark-adapted static perimetry, a clinically significant improvement in fixation location as measured by microperimetry, a clinically significant improvement in fixation stability as measured by microperimetry, a clinically significant improvement in color vision as measured by Hardy Rand and Rittler pseudoisochromatic test, a clinically significant improvement in quality of life scale scores as measured by the Michigan Retinal Degeneration Questionnaire (MRDQ) and / or the Michigan Vision-related Anxiety Questionnaire (MVAQ), an ability to navigate a multi-luminance navigation test, and / or an ability to navigate a multi-luminance navigation test at least two illumination levels lower.

[0278] Clause 26: A method of treating vision loss in a human in need thereof, the method comprising: administering a therapeutically effective amount of one or more immunosuppressive agents to the human; and administering a therapeutically effective amount of a composition comprising photoreceptor precursor cells to a subretinal space of an eye of the human.

[0279] Clause 27: The method of clause 26, wherein the therapeutically effective amount of one or more immunosuppressive agents is administered to the human about two or three weeks prior to administration of the therapeutically effective amount of the composition comprising photoreceptor precursor cells.

[0280] Clause 28: The method of clause 26 or 27, wherein the therapeutically effective amount of one or more immunosuppressive agents is administered to the human for about fifty to about fifty-four weeks after administration of the therapeutically effective amount of the composition comprising photoreceptor precursor cells.Attorney Docket No.: 132042-5007-WO

[0281] Clause 29: The method of any one of clauses 26-28, wherein one or more immunosuppressive agents are selected from the group consisting of: tacrolimus, mycophenolic acid, prednisone, locally administered dexamethasone, and difluprednate.

[0282] Clause 30: The method of any one of clauses 26-29, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered as a single dose.

[0283] Clause 31: The method of any one of clauses 26-30, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered to one eye of the human.

[0284] Clause 32: The method of any one of clauses 26-31, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered to both eyes of the human.

[0285] Clause 33: The method of any one of clauses 26-32, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is surgically administered to the human.

[0286] Clause 34: The method of any one of clauses 26-33, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells includes between about 0.5x106to about 5.0x106cells.

[0287] Clause 35: The method of any one of clauses 26-34, wherein the human is treated with a therapeutically effective amount of the composition comprising photoreceptor precursor cells if the human meets: is at least about 18 years of age, has a confirmed genetic diagnosis of primary photoreceptor disease, has a BCVA between LogMAR 3.9 to LogMAR 0.5 in a study eye, has an ETDRS letter score between 20 and 60 in the study eye, exhibits regions of ellipsoid zone (EZ) loss with preservation of inner nuclear layer (INL) and retinal pigment epithelium (RPE) layer in regions of EZ loss in the retina, has clear ocular media and adequate pupil dilation in both eyes, has serological evidence of prior Epstein-Barr virus infection, or combinations thereof.

[0288] Clause 36: The method of any one of clauses 26-35, wherein the human is not treated with a therapeutically effective amount of the composition comprising photoreceptor precursor cells if the human: has a history or current evidence of scleritis, endophthalmitis, recurrent idiopathic or autoimmune-associated uveitis or vitritis, ocular herpes simplex virus infection, retinal detachment, amblyopia, nystagmus, glaucoma or other significant optic neuropathy,Attorney Docket No.: 132042-5007-WOdiabetic macular edema or diabetic retinopathy, cystoid macular edema that is or could be treated with carbonic anhydrase inhibitors, spherical equivalent refractive error of greater than 8.00 diopters myopia, recent ocular surgery, significant ocular trauma, clinically relevant cataract, clinically relevant vitreomacular adhesion or traction, epiretinal membrane, macular pucker, macular hole, disorders of the ocular media, prior vitreoretinal surgery, monocular vision, tuberculosis infection, recent immunosuppressive therapy, uncontrolled diabetes, previous treatment with cell therapy, gene therapy, or retinal implant, recent investigational therapy, or bone marrow or solid organ transplant; wherein the human does not have a presence of narrow iridocorneal angles contraindicating pupillary dilation, an intraocular pressure (IOP) >21 mmHg, a known allergy to tacrolimus, mycophenolic acid, corticosteroids, basiliximab, or to their ingredients, a contraindication to general anesthesia or to undergoing a surgical procedure, an active ocular inflammation or infection, cancers or pathology of the central nervous system which may alter visual function, cause vision loss, or limit vision recovery, an active malignancy, or a current active bacterial, fungal, or viral infection; wherein the human is not currently taking one or more lOP-lowering medications and is not currently pregnant; and optionally, wherein the human does not express anti-photoreceptor precursor cell HLA antibodies, or the human does not express one or more of anti-photoreceptor precursor cell HLA-C antibodies, anti-photoreceptor precursor cell HLA-DPB1 antibodies, and / or anti-photoreceptor precursor cell HLA-DR antibodies.

[0289] Clause 37: A method of increasing a thickness of an outer nuclear layer of a retina of a human subject, the method comprising surgically administering a composition comprising a therapeutically effective amount of a composition comprising photoreceptor precursor cells to a subretinal space of an eye of the human subject.

[0290] Clause 38: The method of clause 37, wherein the thickness of the outer nuclear layer is measured by spectral domain optical coherence tomography or by fundus autofluorescence.

[0291] Clause 39: The method of clause 37 or 38, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered as a single dose.

[0292] Clause 40: The method of any one of clauses 37-39, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered to one eye of the subject.Attorney Docket No.: 132042-5007-WO

[0293] Clause 41: The method of any one of clauses 37-40, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered to both eyes of the subject.

[0294] Clause 42: The method of any one of clauses 37-41, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells includes between about 0.5x106to about 5.0x106cells.

[0295] Clause 43: The method of any one of clauses 37-42, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells includes rod cells and / or cone cells.

[0296] Clause 44: The method of any one of clauses 37-43, wherein photoreceptor precursor cells are derived from human induced pluripotent stem cells.

[0297] Clause 45: The method of any one of clauses 37-44, wherein the photoreceptor precursor cells differentiate and / or mature into rod cells and / or cone cells.

[0298] The present disclosure is now described with reference to the following Examples. These Examples are provided for the purpose of illustration only and the disclosure should in no way be construed as being limited to these Examples, but rather should be construed to encompass any and all variations which become evident as a result of the teaching provided herein.

[0299] Without further description, it is believed that one of ordinary skill in the art can, using the preceding description and the following illustrative examples, make and utilize the compounds of the present disclosure and practice the claimed methods. The following working examples, therefore, specifically point out the preferred embodiments of the present invention and are not to be construed as limiting in any way the remainder of the disclosure.EXAMPLESExample 1: Methods Used in Non-Clinical Evaluation of BRT-A

[0300] Non-clinical pharmacology evaluations of BRT-A was conducted using a variety of methods. BRT-A is a cell therapy product composed of photoreceptor precursor (PRP) cells derived from human induced pluripotent stem cells.

[0301] Briefly, BRT-A cells were thawed and formulated in a vehicle delivery solution consisting of BSSTMSterile Irrigating Solution (balanced salt solution) supplemented with 0.2% human serum albumin (HSA). The vehicle delivery solution was used as the vehicle control article (VCA)Attorney Docket No.: 132042-5007-WOin the nonclinical studies. BRT-A or VCA were administered as single subretinal injections. Rats were transplanted with either solution at 5 to 10 weeks of age after the loss of the majority of photoreceptors.

[0302] BRT-A was administered as a single subretinal injection (2 pL / eye (a single 2-pL bleb / eye)) to the eye. Prior to BRT-A administration, a subretinal space was created by injecting fluid between the neural retina and the retinal pigment epithelium (RPE), thereby forming a bleb. A subretinal injection provides direct access to the outer nuclear layer (ONL).

[0303] After the administration of BRT-A, the adnexa and anterior portion of both eyes were examined using a slit lamp biomicroscope and the ocular fundi were examined using an indirect ophthalmoscope or Zeiss ophthalmic surgical scope. Prior to examination, pupils were dilated with a mydriatic agent {e.g., 1% tropicamide). In all studies, visual observations of eyes were recorded at approximately every two to three weeks post dose.

[0304] Optical coherence tomography (OCT) imaging was performed using the Envisu™ R-2210 Spectral Domain OCT equipped with InVivoVue (IVV) imaging software and IVV Diver Analysis software (Bioptigen Inc. / Leica Microsystems, Wetzlar, Germany). Images of the area of the bleb (BRT-A or VCA) were collected from treated eyes, and images for corresponding nasal retinal regions were collected from untreated eyes. Averages were calculated for retinal thickness {e.g., the distance between the retinal ganglion cell nerve fiber layer and the retinal pigment epithelium (RPE) and was measured in the images at up to 121 software-determined locations (on a regularly spaced grid)), maximum retinal thickness, replacement ONL thickness, and area of transplant.

[0305] Automated pupillometry was performed on rats on the morning after overnight dark adaptation using an A-2000 small animal pupillometer (Neuroptics Inc., Irvine, CA). Rats were exposed to light stimuli of two wavelengths (622 nm red and 463 nm blue) in increasing intensities from low to high (intensity range, 0.065-11.941 w / m2); all flashes of light stimuli were presented for a duration of 0.5 seconds. Pupil diameters were measured before and after each test flash to calculate the maximum percentage change in pupil size after each stimulus.Example 2: Non-Clinical Evaluation of BRT-A Potency

[0306] A non-clinical pharmacology evaluation of BRT-A was conducted in a Foxn1-S334ter immunocompromised rat model of primary photoreceptor disease (retinitis pigmentosa). Rod and cone photoreceptor (PR) differentiation of BRT-A were evaluated at one-month post dose. At one-month post dose, reformation of the ONL was noted, and the majority of Ku80+ (a human nuclearAttorney Docket No.: 132042-5007-WOmarker) cells were rod or cone photoreceptors (92%). Based on stereology evaluation, those PRs contained an average of 60.2% NRL+ (rod cell marker) rods, while 32.1% were MEF2C+ (cone cell marker) cones, representing a rod:cone ratio of 1.9:1. Approximately 7.6% of the transplanted cells were other retinal cells (e.g., Ku80+ cells that did not co-label with NRL or MEF2C). The percentage of engrafted cells labeled with proliferative cell markers (Ki67 and PHH3) was low and included an average of 0.89% Ki67+ staining cells and 0.02% PHH3+ staining cells. These results demonstrated that BRT-A cells were able to engraft to the desired location, reform the retinal ONL and differentiate into cells required for functional vision (described further in Examples below), thus showing promise for the treatment of human subjects with retinal diseases and vision loss.Example 3: Non-Clinical Evaluation of BRT-A Stability and Function

[0307] Cell engraftment, differentiation, ONL reformation, and functional analysis of BRT-A in the Foxn1-S334ter rat was examined at one-, three-, and six-months post dose. After a single subretinal injection of BRT-A in Foxn1-S334ter rats, a dose-dependent increase in thickness of the replacement ONL and overall area of the graft in the retina was determined by OCT. Pupillometry responses to red and blue lights at different intensities were highly similar across treatment conditions at Day 80 and at five months post dose, which demonstrated that BRT-A does not have an adverse impact on remaining retinal function. Based on histopathology and immunohistochemistry (IHC) evaluation, xenograft cells were durable at six months post dose, including rod and cone PRs that matured to express opsins, presynaptic proteins, and form outer segments. The number of PRs was stable over time and an increase in the number of other retinal cells was noted. The other retinal cell types present within the graft included retinal progenitor cells, amacrine cells, bipolar cells, and glia. The proliferation markers Ki67 and PHH3 were low for both cell batches, particularly at six months post dose. The iPSC marker NANOG was not detected. Microscopic findings were noted with similar incidence and severity in BRT-A-treated, VCA-treated, or untreated eyes at six months post dose, and included minimal-to-moderate mixed cell infiltrates and / or inflammation of the limbus (infiltrates only), conjunctiva, and underlying sclera.Example 4: Non-Clinical Evaluation of BRT-A Engraftment and DifferentiationCell engraftment and differentiation of different batches of BRT-A at three- and six-months post dose was also evaluated. After single subretinal injections of BRT-A cells from two different lots in Foxn1-S334ter rats, xenograft cells were durable at six months post dose, including a majority of engrafted cells that expressed rod or cone PR markers. In eyes treated with either lot of BRT-A cells, there were no significant changes in total engrafted cell numbers at three versus sixAttorney Docket No.: 132042-5007-WOmonths post dose, and the overall composition of engrafted cells from both lots of BRT-A were comparable to each other at both time points. Proliferative markers in eyes treated with either lot were low at three and six months, and trended lowest at six months.Example 5: Non-Clinical Evaluation of Stability of a BRT-A Formulation

[0308] In vivo differentiation of BRT-A cell formulation held at 4 °C for 48 hours prior to subretinal administration was evaluated in the Foxn1-S334ter rat model at one-, three-, and six-months post dose. A 48-hour hold of the prepared dose at 4 °C prior to administration had no pronounced effects on transplanted PR differentiation, maturation, or engraftment versus a suspension that was not held for 48 hours (but rather prepared and injected within 8 hours in prior study). In addition, the composition of other retinal cell types within the engrafted cell population, as well as cell proliferation, was comparable between the conditions. Proliferation markers of Ki67 and PHH3 were low in both studies, and the percentage of proliferative cells declined at one versus six months. In both studies, the iPSC marker NANOG was not detected.Example 6: Non-Clinical Evaluation of BRT-A Durability and Differentiation

[0309] Cell engraftment and differentiation of BRT-A was evaluated in the Foxn1-S334ter rat model at one-, three-, and six-months post dose. After a single subretinal injections of BRT-A cells in Foxn1-S334ter rats, xenograft cells were durable at six months post dose, including a majority of engrafted cells that expressed rod or cone PR markers. There were some changes noted from one to three months post dose in terms of the overall percentage of PRs and other retinal cell types; however, no further changes in these percentages were noted at three versus six months post dose. Proliferative markers in eyes treated were low at one-, three-, and six-months post dose, and were lowest at six months post dose.Example 7: Non-Clinical Evaluation of BRT-A in Rat Model of Retinitis Pigmentosa

[0310] The replacement of PRs and reformation of the retinal ONLby BRT-A was also evaluated in the Foxn1-S334ter rat model of RP at one-, three-, and six-months post dose. A total of 158 rats aged 47 to 64 days received either BRT-A prepared dose at target doses of 2×105, 4×105, or 8×105cells, VCA, or remained untreated (Table 5). BRT-A or VCA was delivered via a single subretinal injection to one eye on Day 1. The BRT-A doses were administered within 48 hours of formulation. Animals were monitored for one-, three-, and six-months post dose.Table 5. Study Design Summary in Foxn1-S334ter RatsAttorney Docket No.: 132042-5007-WOPost-dose dura tion / Target DoseAnimals, N Animals, N=158Treatment dose, concentration,(M; F) 1 3 6(cells / eye) (cells / pL)month months months 14Untreated 0 0 0 0 7M;7F (7M;7F)36VGA 0 0 5M;5F 6M;6F 7M;7F (18M;18F)36BRT-A 2x1051x1055M;5F 6M;6F 7M;7F (18M;18F)36BRT-A 4x1052x1055M;5F 6M;6F 7M;7F (18M;18F)36BRT-A 8x1054x1055M;5F 6M;6F 7M;7F(18M;18F)

[0311] Bench testing was performed to determine the delivered dose when BRT-A prepared dose is passed through the delivery device (syringe and needle). Evaluation parameters included daily cage-side observations, weekly health observations and body weights, ophthalmic examinations, OCT, automated pupillometry, and IHC. Histopathology was performed on listed tissues for all unscheduled deaths. Detailed dilated ophthalmic examinations were performed on all animals before and after BRT-A administration on Day 8 and the one-, three-, and six-month time points. OCT imaging was performed on all rats in the six-month group at one-, three-, and six-months post dose. Additionally in the six-month group, automated pupillometry was performed on one eye prior to surgery (Day -5) and post dose on Days 80 and 165.

[0312] Necropsies were performed at one-, three-, and six-month post dose (scheduled termination), as well as on all unscheduled deaths. At the time of necropsy, macroscopic evaluations were performed. For scheduled terminations, eyes and optic nerves were fixed for histological analysis. Tissues identified as abnormal during scheduled terminations were collected, fixed, and processed to H& E-stained slides for histopathology evaluation. Abnormal tissues from BRT-A-treated scheduled termination animals were also immunolabeled with STEM 121 (human cytoplasm marker). For unscheduled deaths, certain tissues (brain, eyes, optic nerves, liver, lung, kidney, lymph nodes, spleen, testis, ovary, gross lesions) were collected, fixed, and processed to H& E-stained slides for histopathology evaluation.

[0313] For scheduled terminations, eyes were fixed, cryosectioned, and immunolabeled by IHC with Ku80 (human nuclear marker), MEF2C (cone marker), and NRL (rod marker). These markers were quantified by stereology. Additional sections were immunolabeled with the proliferation markers, Ki67 and PHH3, and engrafted cells expressing these markers were quantified.Attorney Docket No.: 132042-5007-WOExpression of markers for PR maturation (RHO, ARR3, M / L opsin, VGLUT 1, PRPH2), as well as other retinal cell types (CHX10, S0X2, PAX6, human GFAP [STEM 123]) were analyzed semi-quantitatively. The iPSC marker NANOG was also assessed. The relative occupancy of Ku80+ in different ocular compartments was semi-quantitatively assessed. In a subset of eyes (three from each dosing group at each time point), additional retinal markers were evaluated, including PR maturation markers AIPL1 (rod and cone PR marker), NR2E3 (rod marker), SAG (rod marker), PPP4R4 (cone marker), GNAT2 (cone marker), and S-opsin (cone marker). SOX9 (expressed in retinal progenitor cells, Muller glia, and retinal astrocytes) was also evaluated. Antibody sensitivity and specificity was assessed for each antibody used in this study.

[0314] Bench testing was performed to determine delivered dose when BRT-Acell formulations were passed through the delivery (syringe and needle) device (Table 6). The mean number of viable cells delivered from the device had a coefficient of variation (CV) of <30% (26%, 21.5%, and 18.6%, for the low, mid, and high doses, respectively). The number of cells ejected from the device from low, mid, and high doses had 95% confidence intervals that did not overlap and were significantly different by statistical evaluation. The average measured viability of dissociated cells was assessed by acridine orange / propidium iodide assay, which indicated that all doses were at least 97% viable.Table 6. Syringe Testing Summary DataTarget dose 2x105cells 4x105cells 8x105cells Mean analytical dose (viable cells) 154,600 315,511 518,867 Standard deviation 40,162 67,711 96,336N 9 9 6% Coefficient of variation 26.0% 21.5% 18.6% 95% Confidence interval (upper limit) 185,472 367,558 619,965 95% confidence interval (lower limit) 123,728 263,464 417,769 Mean % of target dose 77.3% 78.9% 64.9% Average viability 98.5% 99.2% 97.7%

[0315] There were no BRT-A-related clinical observations and surviving animals gained weight during the study. There were fifteen total deaths / sacrifices at unscheduled intervals. Mortality occurred in all groups, including one untreated animal, four treated with VCA, five treated with 2*105BRT-A, three treated with 4*105BRT-A, and two treated with 8x105BRT-A. The majority of the fifteen deaths were related to complications from anesthesia during study-related procedures and no deaths were considered BRT-A-related. In these unscheduled deaths, BRT-A-relatedAttorney Docket No.: 132042-5007-WOmicroscopic findings were limited to the presence of xenograft cells in the treated eyes that were primarily noted in the retina, and less frequently in the choroid at the retinotomy site of two eyes treated with BRT-A. Microscopic findings attributed to the subretinal injection procedure included the presence of a retinotomy site (characterized by a sharply demarcated focus of retinal atrophy) and / or minimal focal hypertrophy of the RPE at the retinotomy site.

[0316] Ophthalmology examination findings were primarily model- or procedure-related. BRT-A-related findings included the presence of transplanted cells predominantly in the retina and occasionally in the vitreous. OCT images showed a dose-dependent response on retinal / replacement ON L thickness and overall area of the graft (FIG. 1). Retinas were reattached by one month, which was the first post-dose time point examined by OCT (with the exception of one eye treated with BRT-A that was detached at one month but had reattached by three months). The graft size increased in thickness and area from one to six months post dose, with the implanted regions appearing uniform in apparent density and structure. At six months post dose, the estimated average replacement ONL thickness was 35.5 pm, 51.8 pm, and 82.4 pm for eyes treated with target BRT-A dose levels of 2x105, 4x105, or 8x105cells, respectively.

[0317] Based on the pupillometry data, there were no adverse effects on visual function when comparing eyes treated with BRT-A, VCA, or untreated eyes (FIG. 2). In particular, pupillometry responses to red and blue lights at different intensities were similar across treated and untreated conditions at Days 80 and 165 post dose, demonstrating the functional similarity of the eyes treated with BRT-A compared with VCA-treated and untreated eyes.

[0318] For all scheduled terminations, the relative occupancy of different ocular compartments with xenograft cells was assessed in eyes treated with BRT-A, including the retina, vitreous cavity, choroid, optic nerve, and sclera, and were scored semi-quantitatively on a 0 to 5 scale (Table 7).In all eyes with xenograft cells present, the majority of cells were engrafted in the retina. In general, there was an increase in the number of engrafted cells in the retina from one to six months post dose for each tested BRT-A dose level as quantified by stereology. Xenograft cells were also observed in the vitreous in a minority of eyes treated with BRT-A at each dose and time point examined. When present, those cells occupied <5% of the vitreous cavity. Transplanted cells were found in the choroid of two BRT-A (8x 105)-treated eyes at six months post dose and occupied <5% of the choroid. Including all Eyes treated with BRT-A, 99% had cells engrafted in the retina, 28% had cells located in the vitreous, and 2% of eyes had cells located in the choroid. Cells located in the vitreous are presumed to have refluxed into the vitreous cavity at the time of injection. Cells located in the choroid are presumed to have been deposited into the choroid atAttorney Docket No.: 132042-5007-WOthe time of injection (e.g., needle tip inadvertently inserted into the choroid). Based on histopathology and IHC, there were no xenograft cells observed in the optic nerve or sclera in any eye at any time point evaluated.Table 7. Ocular Compartment Xenograft Occupancy in S334ter-Foxn1 Rats After BRT-A AdministrationPost-dose1 month 3 months 6 months durationTarget BRT-A2x1054X1058x1052x1054x1058x1052x1054x1058x10 dose, cells5Total animals in10 10 10 12 12 11 9 11 13 each groupRetina1 0 0 0 0 0 0 0 0 (no cells present)Retina (6%-10%) 9 8 1 3 0 0 0 0 0 Retina (11%- 0 2 9 9 1 0 0 0 0 25%)Retina (26%- 0 0 0 0 11 1 9 1 2 50%)Retina (>50%) 0 0 0 0 0 10 0 10 11 Vitreous6 8 8 8 9 8 7 6 11 (no cells present)Vitreous (<5%) 4 2 2 4 3 3 2 5 2 Choroid10 10 10 12 12 11 9 11 11 (no cells present)Choroid (<5%) 0 0 0 0 0 0 0 0 2 Optic nerve10 10 10 12 12 11 9 11 13 (no cells present)Sclera10 10 10 12 12 11 9 11 13(no cells present)

[0319] In animals euthanized at scheduled necropsies, the engrafted cells were durable at the six-month time point. By stereological cell counts, the estimated total engrafted cell numbers per eye increased from one to six months, including a statistically significant increase in the number of PRs and other retinal cells (FIG. 3).

[0320] There were some changes noted in the percentage of PR and other retinal cell types within the engrafted cell population from one to three months, including a small reduction in the percentage of PRs and an increase in the percentage of other retinal cells. However, the relative percentages of these cell types were consistent thereafter (FIG. 4). The majority of engrafted cells were PRs at each timepoint analyzed. Across all eyes and doses, the average percentage ofAttorney Docket No.: 132042-5007-WOengrafted cells that expressed PR markers at six months was 69.0%. Within the overall engrafted PR population at six months, rods and cones were present at an approximately 1.6:1 ratio.

[0321] PR maturation was assessed by immunolabeling with a panel of mature rod and cone markers. Rods and cones formed outer segments starting at one-month post dose, and the majority expressed additional markers of PR maturation by three-months post dose. Engrafted PRs expressed the pan-PR marker AIPL1 and the formation of PR outer segments was confirmed by PRPH2 labeling. Engrafted cones matured to express cone opsins, including a majority of engrafted cones that expressed M / L opsin, and a minority of cones that expressed S-opsin. Additional key cone PR proteins were also expressed, including cone ARR3, PPP4R4, and GNAT2. Rod PRs matured and expressed key rod-specific proteins, including rhodopsin (RHO), NR2E3, and SAG. Host bipolar cells extended long dendrites into the replacement ONL and were found juxtaposed to presynaptic proteins expressed by transplanted PRs, indicating anatomic integration of transplanted PRs with the host retina.

[0322] By semiquantitative analysis, markers for other retinal cell types including CHX10, SOX2, and PAX6 increased from one to three months post dose but were largely consistent from three to six months. GFAP increased from one to six months, indicating maturation of retinal glia over time. Expression of CHX10, SOX2, PAX6, and GFAP indicated the presence of amacrine cells, bipolar cells, and retinal glia in the xenograft. Rod and cone PRs combined made up a majority of engra...

Claims

1. Attorney Docket No.: 132042-5007-WO2.WHAT IS CLAIMED IS:

1. A method of treating an inherited retinal disease in a subject in need thereof, the method comprising:4.administering a therapeutically effective amount of a composition comprising photoreceptor precursor cells to an eye of the subject in need thereof.

2. The method of claim 1, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is surgically administered to the eye of the subject.

3. The method of claim 1 or 2, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is surgically administered into a subretinal space of the eye of the subject.

4. The method of any one of claims 1-3, wherein a subretinal injection that comprises the therapeutically effective amount of the composition comprising photoreceptor precursor cells is surgically administered into the subretinal space of the eye of the subject.

5. The method of any one of claims 1-4, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered as a single dose.

6. The method of any one of claims 1-5, wherein the subject is a human.

7. The method of claim 6, wherein the human is at least 18 years of age.

8. The method of any one of claims 1-7, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells includes between about 0.5x106to about 5.0x106photoreceptor precursor cells.

9. The method of any one of claims 1-8, wherein the subject is administered one or more immunosuppressive agents beginning about two to three weeks prior to administration of the therapeutically effective amount of the composition comprising photoreceptor precursor cells.Attorney Docket No.: 132042-5007-WO10. The method of claim 9, wherein one or more immunosuppressive agents are selected from the group consisting of: tacrolimus, mycophenolic acid, prednisone, locally administered dexamethasone, and difluprednate.

11. The method of claim 9 or 10, wherein one or more immunosuppressive agents are administered to the subject for about fifty-two weeks after the administration of the therapeutically effective amount of photoreceptor precursor cells.

12. The method of any one of claims 1-11, wherein the composition comprising photoreceptor precursor cells includes rod cells and / or cone cells.

13. The method of claim any one of claims 1-12, wherein the photoreceptor precursor cells are derived from human induced pluripotent stem cells.

14. The method of any one of claims 1-13, wherein the photoreceptor precursor cells are allogeneic.

15. The method of any one of claims 1-14, wherein the inherited retinal disease affects a function and / or structure of a retina in the eye of the subject.

16. The method of any one of claims 1-15, wherein the inherited retinal disease is a primary photoreceptor disease.

17. The method of claim 16, wherein the primary photoreceptor disease is selected from the group consisting of: retinitis pigmentosa, Usher Syndrome, cone-rod disease, rod-cone disease, cone dystrophy, and cone-rod dystrophy.

18. The method of any one of claims 1-17, wherein the subject has diminished vision due to cellular loss of rod cells and / or cone cells.

19. The method of any one of claims 1-18, wherein the method of treating results in a change in retinal structure in the eye in the subject.Attorney Docket No.: 132042-5007-WO20. The method of claim 19, wherein the change in retinal structure is an increase in thickness of an outer retinal layer and / or improved retinal structure organization.

21. The method of claim 20, wherein the thickness of the outer retinal layer is measured by spectral domain optical coherence tomography or by fundus autofluorescence.

22. The method of any one of claims 1-21, wherein the photoreceptor precursor cells differentiate and / or mature into cells that exhibit one or more of the following properties: form inner segments, form outer segments, express opsin, or traffic rhodopsin to outer segments by rods.

23. The method of any one of claims 1-22, wherein the method of treating leads to reformation of an outer nuclear layer.

24. The method of any one of claims 1-23, wherein the method of treating improves visual function and / or functional vision in the subject, wherein the subject is human.

25. The method of claim 24, wherein visual function and / or functional vision is improved where, as compared to baseline, the human exhibits one or more of:29.a. a mean retinal sensitivity greater than or equal to seven decibels as measured by microperimetry,30.b. light sensitivity improvement as measured by full-field stimulus testing,31.c. a clinically significant improvement in retinal sensitivity as measured by static perimetry,32.d. a best corrected visual acuity (BCVA) greater than or equal to 0.3 Logarithm of the Minimum Angle of Resolution (LogMAR) units and > 15 Early Treatment of Diabetic Retinopathy Study (ETDRS) letter score, optionally wherein the human has a BCVA at baseline between LogMAR 3.9 to LogMAR 0.5 in a study eye and / or has an ETDRS letter score at baseline of 60 or less in the study eye,33.e. a low luminance visual acuity (LLVA) greater than or equal to 0.3 LogMAR units and > 15 ETDRS letter score,34.f. a clinically significant improvement in retinal sensitivity as measured by dark-adapted static perimetry,35.g. a clinically significant improvement in fixation location as measured by microperimetry, h. a clinically significant improvement in fixation stability as measured by microperimetry, Attorney Docket No.: 132042-5007-WO36.i. a clinically significant improvement in color vision as measured by Hardy Rand and Rittler pseudoisochromatic test,37.j. a clinically significant improvement in quality of life scale scores as measured by the Michigan Retinal Degeneration Questionnaire (MRDQ) and / or the Michigan Vision- related Anxiety Questionnaire (MVAQ),38.k. an ability to navigate a multi-luminance navigation test, and / or39.l. an ability to navigate a multi-luminance navigation test at least two illumination levels lower.

26. A method of treating vision loss in a human in need thereof, the method comprising:41.administering a therapeutically effective amount of one or more immunosuppressive agents to the human; and42.administering a therapeutically effective amount of a composition comprising photoreceptor precursor cells to a subretinal space of an eye of the human.

27. The method of claim 26, wherein the therapeutically effective amount of one or more immunosuppressive agents is administered to the human about two or three weeks prior to administration of the therapeutically effective amount of the composition comprising photoreceptor precursor cells.

28. The method of claim 26 or 27, wherein the therapeutically effective amount of one or more immunosuppressive agents is administered to the human for about fifty to about fifty-four weeks after administration of the therapeutically effective amount of the composition comprising photoreceptor precursor cells.

29. The method of any one of claims 26-28, wherein one or more immunosuppressive agents are selected from the group consisting of: tacrolimus, mycophenolic acid, prednisone, locally administered dexamethasone, and difluprednate.

30. The method of any one of claims 26-29, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered as a single dose.Attorney Docket No.: 132042-5007-WO31. The method of any one of claims 26-30, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered to one eye of the human.

32. The method of any one of claims 26-31, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered to both eyes of the human.

33. The method of any one of claims 26-32, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is surgically administered to the human.

34. The method of any one of claims 26-33, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells includes between about 0.5x106to about 5.0x106cells.

35. The method of any one of claims 26-34, wherein the human is treated with a therapeutically effective amount of the composition comprising photoreceptor precursor cells if the human: is at least about 18 years of age, has a confirmed genetic diagnosis of primary photoreceptor disease, has a BCVA between LogMAR 3.9 to LogMAR 0.5 in a study eye, has an ETDRS letter score between 20 and 60 in the study eye, exhibits regions of ellipsoid zone (EZ) loss with preservation of inner nuclear layer (INL) and retinal pigment epithelium (RPE) layer in regions of EZ loss in the retina, has clear ocular media and adequate pupil dilation in both eyes, has serological evidence of prior Epstein-Barr virus infection, or combinations thereof.

36. The method of any one of claims 26-35, wherein the human is not treated with a therapeutically effective amount of the composition comprising photoreceptor precursor cells if the human: has a history or current evidence of scleritis, endophthalmitis, recurrent idiopathic or autoimmune-associated uveitis or vitritis, ocular herpes simplex virus infection, retinal detachment, amblyopia, nystagmus, glaucoma or other significant optic neuropathy, diabetic macular edema or diabetic retinopathy, cystoid macular edema that is or could be treated with carbonic anhydrase inhibitors, spherical equivalent refractive error of greater than 8.00 diopters myopia, recent ocular surgery, significant ocular trauma, clinically relevant cataract, clinically relevant vitreomacular adhesion or traction, epiretinal membrane, macular pucker, macular hole, disorders of the ocular media, prior vitreoretinal surgery, monocularAttorney Docket No.: 132042-5007-WO53.vision, tuberculosis infection, recent immunosuppressive therapy, uncontrolled diabetes, previous treatment with cell therapy, gene therapy, or retinal implant, recent investigational therapy, or bone marrow or solid organ transplant;54.wherein the human does not have a presence of narrow iridocorneal angles contraindicating pupillary dilation, an intraocular pressure (IOP) >21 mmHg, a known allergy to tacrolimus, mycophenolic acid, corticosteroids, basiliximab, or to their ingredients, a contraindication to general anesthesia or to undergoing a surgical procedure, an active ocular inflammation or infection, cancers or pathology of the central nervous system which may alter visual function, cause vision loss, or limit vision recovery, an active malignancy, or a current active bacterial, fungal, or viral infection;55.wherein the human is not currently taking one or more lOP-lowering medications and is not currently pregnant; and56.optionally, wherein the human does not express anti-photoreceptor precursor cell HLA antibodies, or the human does not express one or more of anti-photoreceptor precursor cell HLA-C antibodies, anti-photoreceptor precursor cell HLA-DPB1 antibodies, and / or anti-photoreceptor precursor cell HLA-DR antibodies.

37. A method of increasing a thickness of an outer nuclear layer of a retina of a human subject, the method comprising surgically administering a composition comprising a therapeutically effective amount of a composition comprising photoreceptor precursor cells to a subretinal space of an eye of the human subject.

38. The method of claim 37, wherein the thickness of the outer nuclear layer is measured by spectral domain optical coherence tomography or by fundus autofluorescence.

39. The method of claim 37 or 38, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered as a single dose.

40. The method of any one of claims 37-39, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered to one eye of the subject.Attorney Docket No.: 132042-5007-WO41. The method of any one of claims 37-40, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells is administered to both eyes of the subject.

42. The method of any one of claims 37-41, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells includes between about 0.5x106to about 5.0x106cells.

43. The method of any one of claims 37-42, wherein the therapeutically effective amount of the composition comprising photoreceptor precursor cells includes rod cells and / or cone cells.

44. The method of any one of claims 37-43, wherein the photoreceptor precursor cells are derived from human induced pluripotent stem cells.

45. The method of any one of claims 37-44, wherein the photoreceptor precursor cells differentiate and / or mature into rod cells and / or cone cells.

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