Autologous serum insert for treating an ocular condition

Abstract

An article of manufacture comprising a solid autologous serum ocular insert. In certain embodiments, the article further comprises a backing layer adjacent to the solid autologous serum ocular insert. The insert can be administered to an ocular surface of a subject for treating an ocular condition.

Description

[0001] AUTOLOGOUS SERUM INSERT FOR TREATING AN OCULAR CONDITION

[0002] CROSS REFERENCE TO RELATED APPLCIATION

[0003] This claims the benefit of U.S. Provisional Application No. 63 / 543,413, filed October 10, 2023, which is incorporated herein by reference in its entirety.

[0004] BACKGROUND

[0005] Dry eye disease (DED) is a chronic condition on the ocular surface that affects over 16 million adults in the US alone and its prevalence is expected to increase as the population ages. The costs of treating DED are staggering, with an estimate of nearly $4 billion in annual direct costs to the healthcare system. DED is characterized by a failure to produce sufficient quality or volume of tears to maintain proper moisture of the ocular surface, leading to significant, negative effects on vision and quality of life.

[0006] Current treatment approaches include conservative options like over-the-counter lubricants artificial tears, lid hygiene, and identification / reduction of environmental triggers. When these options fail to control DED progression, prescriptive topical options such as cyclosporine A (CsA) are often the next line of treatment. Despite their widespread use, the overall efficacy of CsA eyedrops is considered suboptimal. For patients with a significant inflammatory component contributing to their DED, prescription lifitegrast is an option, yet not without serious ocular discomfort and limited applicability for many patients.

[0007] One appealing alternative is the use of blood products, most notably autologous serum eye drops (ASEDs), which share many similarities with native tears. Human serum contains a multitude of growth factors and has been used widely in wound healing and regenerative medicine applications outside of ophthalmology. ASEDs have been shown repeatedly to achieve favorable results treating DED, both objectively using clinical assessments and symptomatically based on patient self-reporting. Since the first reported use of ASED therapy for DED in 1975, this has become a very popular approach.

[0008] ASEDs arc generally accepted to be more efficient than artificial tears and with far fewer side effects than corticosteroid or CsA eye drops. Still, there are significant drawbacks associated with their use. First, there is no one standard approach for preparing and storing ASEDs and variations exist from clinic to clinic, making predictable and reproducible results nearly impossible. Clinical preparation is cumbersome and requires multiple time-consuming steps and frequent patient visits to collect blood. The frequency of blood collection is primarily due to the lack of preservatives (critical in preventing further irritation of the ocular surface) and need for refrigeration to preserve biological activity of the growth factors in serum and prevent contamination.

[0009] Another major disadvantage of ASED therapy is the need for repeated and frequent drop instillation for ongoing treatment. Patients must self-administer ASEDs every 2-3 hours for optimal results, due to the short duration of physiological action of serum proteins. Conventional ASED preparations use saline solution to achieve dilutions of 20-50%. One study reports that approximately 150 bottles are produced with a single blood donation, with bottles being stored frozen until the day of use, refrigerated during that day, and disposed of at the end of the day with any remaining serum. Previous studies have suggested that lyophilization can dramatically increase shelf life of prepared ASED, but this effect is negated once eye drops have been reconstituted for use, and it fails to address the frequent dosing needed. Others have reported that plasma preparations rich in growth factors (platelet rich plasma, PRP, or platelet rich fibrin, PRF) offer superior regenerative effects due to an absence of pro-inflammatory leukocytes and larger volumes collected per donation. These blood products can be used as eye drops, injections, or even solid implants. The preparation requires proficiency in a particular series of pipetting steps that serum alone does not. Further, the complexities of immune regulation on the ocular surface are such that it remains unclear if a complete absence of leukocytes is in fact beneficial.

[0010] While incremental advances have been demonstrated with strategies such as hyaluronic acid dilution or alternate blood products, there still exists a critical need for improved preparation, storage, and use methods for DED therapy. Such improvements could transform the clinical management of DED and dramatically enhance the experience of ASED treatment for patients.

[0011] SUMMARY

[0012] Disclosed herein is an article of manufacture comprising a solid autologous serum ocular insert. In certain embodiments, the article further comprises a backing layer adjacent to the solid autologous serum ocular insert. The insert can be administered to an ocular surface of a subject for treating an ocular condition.

[0013] DETAILED DESCRIPTION

[0014] Overview of Terms

[0015] The following explanations of terms are provided to better describe the present disclosure and to guide those of ordinary skill in the art in the practice of the present disclosure. As used herein, “comprising” means “including” and the singular forms “a” or “an” or “the” include plural references unless the context clearly dictates otherwise. The term “or” refers to a single element of stated alternative elements or a combination of two or more elements, unless the context clearly indicates otherwise.

[0016] Unless explained otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this disclosure belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present disclosure, suitable methods and materials are described below. The materials, methods, and examples are illustrative only and not intended to be limiting, unless otherwise indicated. Other features of the disclosure are apparent from the following detailed description and the claims.

[0017] Although the operations of exemplary embodiments of the disclosed method may be described in a particular, sequential order for convenient presentation, it should be understood that disclosed embodiments can encompass an order of operations other than the particular, sequential order disclosed. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Further, descriptions and disclosures provided in association with one particular embodiment are not limited to that embodiment and may be applied to any embodiment disclosed.

[0018] Unless otherwise indicated, all numbers expressing quantities of components, molecular weights, percentages, temperatures, times, and so forth, as used in the specification or claims are to be understood as being modified by the term “about.” Accordingly, unless otherwise indicated, implicitly or explicitly, the numerical parameters set forth are approximations that can depend on the desired properties sought and / or limits of detection under standard test conditions / methods. When directly and explicitly distinguishing embodiments from discussed prior art, the embodiment numbers are not approximates unless the word “about” is recited. Furthermore, not all alternatives recited herein are equivalents.

[0019] To facilitate review of the various embodiments of the disclosure, the following explanations of specific terms are provided.

[0020] “Administration” as used herein is inclusive of administration by another person to the subject or self-administration by the subject.

[0021] Ocular region: Any area of the eye, including the anterior and posterior segment of the eye, and which generally includes, but is not limited to, any functional (e.g., for vision) or structural tissues found in the eyeball, or tissues or cellular layers that partly or completely line the interior or exterior of the eyeball. Ocular regions include the anterior chamber, the posterior chamber, the vitreous cavity, the choroid, the suprachoroidal space, the subretinal space, the conjunctiva, the subconjunctival space, the episcleral space, the intracorneal space, the epicorneal space, the sclera, the pars plana, surgically-induced avascular regions, the macula, and the retina.

[0022] "Ocular condition" means a disease, ailment or condition which affects or involves the eye or one of the parts or regions of the eye. Broadly speaking the eye includes the eyeball and the tissues and fluids which constitute the eyeball, the periocular muscles (such as the oblique and rectus muscles) and the portion of the optic nerve which is within or adjacent to the eyeball.

[0023] Subject: Human and non-human subjects, including avian species and non-human mammals, such as non-human primates, companion animals (such as dogs and cats), livestock (such as ungulates and / or ruminants), as well as non-domesticated animals, such as the big cats.

[0024] Therapeutically Effective Amount: A quantity of a specified therapeutic agent sufficient to achieve a desired effect in a subject being treated with that therapeutic agent. Ideally, a therapeutically effective amount of an agent is an amount sufficient to inhibit or treat the disease or condition without causing a substantial cytotoxic effect in the subject. The therapeutically effective amount of an agent will be dependent on the subject being treated, the severity of the affliction, and the manner of administration of the therapeutic composition. For example, a "therapeutically effective amount" may be a level or amount of agent needed to treat dry eye disease, or reduce or prevent dry eye disease without causing significant negative or adverse side effects to the eye or a region of the eye.

[0025] “Treatment” refers to a therapeutic intervention that ameliorates a sign or symptom of a disease or pathological condition after it has begun to develop, or administering a compound or composition to a subject who does not exhibit signs of a disease or exhibits only early signs for the purpose of decreasing the risk of developing a pathology or condition, or diminishing the severity of a pathology or condition. As used herein, the term “ameliorating,” with reference to a disease or pathological condition, refers to any observable beneficial effect of the treatment. The beneficial effect can be evidenced, for example, by a delayed onset of clinical symptoms of the disease in a susceptible subject, a reduction in severity of some or all clinical symptoms of the disease, a slower progression of the disease, an improvement in the overall health or well-being of the subject, or by other parameters well known in the art that are specific to the particular disease. The phrase “treating a disease” refers to inhibiting the full development of a disease, for example, in a subject who is at risk for a disease such as dry eye disease.

[0026] Autologous Serum Ocular Insert Embodiments

[0027] Disclosed herein is a novel autologous serum ocular insert (ASOI). The ASOI is a small and easily handled solid insert, which resides in the lower fornix. The ASOI achieves the same level of protein delivery as a full daily course of ASEDs. The ASOI delivers serum proteins more efficiently to the ocular surface and may include a backing layer that directs proteins toward the eye and not the eyelid. The production steps require minimal additives and the overall production process is quick and simple.

[0028] Solid bodies can be fabricated using serum only. For example, lyophilized serum can be molded (for example, via compression molding) into an insert. In other embodiments, the insert can be made via solvent evaporation, casting or spin coating. The insert may have any shape, for example, circular, oval, triangular (e.g., pie-shaped, cut from a whole circle), or half-circular. In certain embodiments, the insert is circular and has a diameter of 2 to 20 mm, more particularly 5 to 10 mm. In certain embodiments, the solid serum insert has a thickness of 0.1 to 1.5 mm.

[0029] In certain embodiments, a backing layer adjacent to the solid autologous scrum ocular insert is included. The backing layer limits diffusion of the serum toward the eyelid, thus directing the serum towards the ocular surface. When inserted onto the eye, the backing layer undergoes dissolution and can release solvated backing material as a comfort agent. The backing layer may be fabricated from a material having a suitable viscosity. In another embodiment, a water-soluble hydrogel could be used if it is safe to use in the ocular region. Illustrative materials for the backing layer include carboxymethylcellulose, hydroxypropyl methylcellulose, hydroxypropyl cellulose, polyethylene glycol, polyvinyl alcohol, propylene glycol, hydroxypropyl guar, polyvinylpyrrolidone, glycerine, and mineral oil.

[0030] Similar to the ASOI, the backing layer can be fabricated by molding a powder form of the desired material into a solid body. The backing material solid body is then pressed together with the ASOI resulting in an insert that includes the ASOI and an adjacent backing layer.

[0031] In certain embodiments, the ASOI including the backing layer has a thickness of 0.2 to 2.0 mm.

[0032] In certain embodiments, the ASOI is excipient-free. For example, the ASOI does not include any carriers, binders, extenders, disintegrants, diluents and lubricants. In certain embodiments, the ASOI is preservative-free. Methods of Using Autologous Serum Ocular Insert Embodiments

[0033] The ASOI is useful for treating an ocular condition, particularly an ocular surface condition. In certain embodiments, the ASOI is useful for treating dry eye disease. In certain embodiments, the ASOI is useful for treating exposure keratitis or corneal injury.

[0034] In certain embodiments, the ASOI can deliver a total serum protein amount of 8 to 50 mg per day.

[0035] In certain embodiments, only a single ASOI is administered to a subject once a day. In certain embodiments a single ASOI is administered per day over a period of days. The ASOI may be inserted in the subject’s lower fornix.

[0036] In certain aspects, the ASOI requires less frequent dosing compared to ASEDs. In certain aspects, the ASOI has longer shelf stability, and simpler storage methods, compared to ASEDs.

[0037] In certain aspects, the ASOI exhibits epitheliotropic activity and biocompatibility.

[0038] In certain aspects, the ASOI requires only one day of serum delivery per insert.

[0039] In certain embodiments, patients may get a minimum of 33% more doses per blood draw with ASOIs compared to the current drop protocol and require no more than 2-3 blood draws per year with ASOIs as opposed to 5-6 times a year currently with ASEDs.

[0040] Examples

[0041] Example 1 - Fabrication of solid autologous serum insert

[0042] 100ml of sterile human serum was flash frozen using liquid nitrogen and lyophilized for a minimum of 48 hours. The lyophilized serum was then loaded into a 6mm evacuable pellet die on a Carver two-post press and compressed using 2500 lbs for 30 min resulting in a 6 mm disc. No excipients were used to prepare this insert, which was able to be handled and cut into even pieces easily. Protein quantification using bicinchoninic acid (BCA) assay confirmed that there was no significant loss of protein mass during processing. The 6 mm disc has a serum mass of 290 mg. In certain examples, the 6 mm disc is cut into 6 even triangular pieces, which each individual piece corresponding to an ASOI with a daily dose to match the current clinical standard.

[0043] Example 2 - Fabrication of a dual-layered solid autologous serum insert

[0044] A carboxymethylcellulose (CMC) backing layer was pressed together with the ASOI resulting in an insert that includes the ASOI and an adjacent CMC backing layer. CMC is non-cytotoxic and has beneficial effects on corneal epithelium, and is used as a comfort agent. The serum layer will be placed adjacent to the ocular surface to provide more direct diffusion of proteins to the site of interest, and the CMC layer provides added comfort and structural support to the insert, which can be handled easily. CMC Protein quantification using bicinchoninic acid (BCA) assay confirmed that there was no loss of protein mass during processing. Testing

[0045] The suitability of ASOI as a replacement for ASED will be evaluated by comparing the two treatment methods in a healthy rabbit model. We will monitor tear film concentration of the following proteins known to influence ocular surface homeostasis: lactoferrin, EGF, TGFb, IgA, HGF, and PDGF over time, as well as osmolarity, ASOI degradation, and ocular surface health. We will correlate concentration to likelihood of efficacy in dry eye disease using known parameters for those same key proteins in native tears. The outcome of this evaluation will be a direct comparison of a once-daily ASOI to a typical course of daily ASED. A second in vivo study will use rabbits to evaluate compatibility of the ASOI in a benzalkonium chloride-induced dry eye model.

[0046] For example, healthy New Zealand white rabbits will have the nictitating membrane in both eyes removed to recapitulate human anatomy and ensure proper placement of the inserts. Triangular ASOIs will then be placed in the inferior fornix of the right eye only. The paired eye will receive 20% serum eye drops 8 times per day as a positive control. Tear film collection will be carried out twice per day using Schirmer strips that are then soaked in DI water. These samples will be assayed using individual enzyme-linked immunosorbent assays (ELISAs) for the following factors, all of which are known to be key contributors to ocular surface health(31-34): lactoferrin, EGF, TGF , IgA, HGF, and PDGF. We will compare tear film concentration to expected amounts in natural tear film those measured in the positive control ASED as a preliminary evaluation of efficacy in treating dry eye disease. We will also measure tear film osmolarity using a freezing point osmometer (Advanced Instruments) against the reference value of 275-307 mOsm / L for healthy eyes (35). We will also track degradation of the insert over time via visual analysis and evaluate ocular surface health each day of the study via slit lamp examination. This study will last a total of 5 days, with a new ASOI placed in the fornix at the same time each day. Rabbits will then be euthanized and both eyes enucleated for histology. The resulting slides will be analyzed by a masked observer for signs of irritation on the cornea, sclera, and conjunctiva.

[0047] In addition to the 10-rabbit study, we will conduct a pilot study of 4 rabbits in a benzalkonium chloride (BAC)-induced dry eye model. This study will again use New Zealand white rabbits with the nictitating membrane resected. One eye will be randomized to receive topical administration of 0.1% BAC twice daily for 7 days. On day 7, that same eye will receive a single ASOI before sacrifice 24 hours later. Ocular surface health will be monitored at baseline and on days 3, 5, 7, and upon sacrifice using Schirmer test, rose bengal staining, and fluorescein staining. The primary goal of this study is to determine whether sufficient tolerability (as measured by rabbit facial grimace scoring(37)) and solvation (determined qualitatively through retention analysis) of the insert is possible in an aqueous deficient dry eye model.

[0048] Using commercially obtained human serum samples, we will longitudinally evaluate these characteristics of the ASOI: pH, osmolality, protein concentration, mass, and bioactivity. Standard cellbased assays of growth factor signaling for proliferation and migration will be used to test releasates from ASOIs stored for up to 12 months at two sets of storage conditions, accelerated and long-term. The outcome of this aim will be a time-dependent profile of bioactivity in both the ASOI and standard ASED. We anticipate that bioactivity of fresh ASOIs will be comparable to that of fresh ASED, and that shelf life of the ASOI will significantly exceed that of the unaltered ASED. These tests are based on ICH guidelines for stability of drug products, with shelf life will be defined as the longest time period at which there are no statistically significant changes in any single property compared to baseline

[0049] In view of the many possible embodiments to which the principles of the disclosed invention may be applied, it should be recognized that the illustrated embodiments are only preferred examples of the invention and should not be taken as limiting the scope of the invention.

Claims

What is claimed is:

1. An article of manufacture comprising a solid autologous serum ocular insert.

2. The article of claim 1, wherein the insert has a thin circular shape.

3. The article of claim 2, wherein the insert has a diameter of 2 to 20 mm4. The article of claim 1, wherein the insert is in the form of a disc.

5. The article of any one of claims 1 to 4, wherein the insert has a thickness of 0.1 to 1.5 mm.

6. The article of any one of claims 1 to 5, further comprising a backing layer adjacent to the solid autologous serum ocular insert.

7. The article of claim 6, wherein the backing layer comprises a solid comfort agent.

8. The article of claim 6, wherein the backing layer comprises carboxymethylcellulose, hydroxypropyl mcthylccllulosc, hydroxypropyl cellulose, polyethylene glycol, polyvinyl alcohol, propylene glycol, hydroxypropyl guar, polyvinylpyrrolidone, glycerine, mineral oil, or a combination thereof.

9. The article of any one of claims 6 to 8, wherein the backing layer has a thickness of 0.2 to 2.0 mm.

10. The article of any one of claims 1 to 9, wherein the article is excipient-free.

11. A method comprising administering the insert of any one of claims 1 to 10 to an ocular surface of a subject for treating an ocular condition.

12. The method of claim 11, comprising inserting the insert at the lower fornix of the subject.

13. The method of claim 11 or 12, wherein the ocular condition is dry eye disease.

14. The method of claim 11 or 12, wherein the ocular condition is exposure keratitis or corneal injury.

15. The method of any one of claims 11 to 14, wherein the insert delivers a total serum protein amount of 8 to 50 mg per day.