Anti-A beta vaccine therapy

Abstract

used to induce anti-Aβ immune responses in human subjects without inducing severe adverse events, a. Amyloid beta (Aβ)-derived peptide antigens presented on the surface of liposomes comprising, consisting essentially of, or consisting of amino acids 1-15 of Aβ b. Adjuvants containing monophosphoryl lipid A (MPLA) The liposome vaccine composition comprises: a beta amyloid (Aβ)-derived peptide antigen (SEQ ID NO: 1) administered in an amount of 300 to 2000 μg, preferably about 1000 μg; and MPLA administered in an amount of 15 to 600 μg, preferably about 175 μg. The liposome vaccine composition is administered intramuscularly or subcutaneously.

Description

Technical Field

[0001] Field of the Invention The present invention relates to an anti-a beta therapeutic vaccine and its use for inducing an anti-Aβ immune response without inducing severe adverse events. Such vaccines are useful for the treatment and prevention of conditions characterized by or associated with loss of cognitive memory function, such as diseases, particularly amyloid-beta related diseases or conditions, or Alzheimer's disease (AD) and Down syndrome (DS) including Down syndrome-related Alzheimer's disease. The vaccine incorporates an Aβ-derived peptide antigen on the outer surface of liposomes.

Background Art

[0002] Background Alzheimer's disease (AD) is a destructive, progressive neurodegenerative disorder characterized by loss of cognitive function, including memory, and loss of the ability to perform routine daily activities. AD affects approximately 40 million patients worldwide, and the number is increasing rapidly with the aging of the population. The major neuropathological change in the brains of AD patients is neuronal death, mainly in memory and cognition-related regions (Soto, 1999). One of the most prominent pathological features of AD is the presence of amyloid beta (a beta, A beta, β-amyloid, Aβ) plaques in the brains of affected individuals (Soto, 1999). Aβ plaques are formed by Aβ peptides 39-43 amino acids in length, which are in a random coil form in their native non-pathological form. During the transition to a pathological state, they are mainly converted to a β-sheet secondary structure and spontaneously aggregate into insoluble deposits.

[0003] Several currently available AD treatments are thought to act mainly symptomatically. Despite considerable efforts over the years to develop treatments, no disease-modifying treatments for AD have been approved to date. Attempts have been made over the long term to develop immunotherapies that would neutralize pathological Aβ in the affected brain (Winblad, 2014). Vaccines have the advantage of stimulating the immune system to produce a pool of very specific antibodies, albeit slightly different, and at the same time, if necessary, the response can be further recalled by booster vaccination.

[0004] However, there are several major challenges with the active immunization (vaccination) approach against Aβ. Amyloid beta is a so-called self-antigen to which humans are constantly exposed. Therefore, it is very difficult to break immune tolerance to it and induce an antibody response. Furthermore, it is very difficult to induce a strong immune response to a vaccine in elderly patients such as those with AD, as their immune system is already weakened and the number of immune cells is reduced.

[0005] Initial trial reports showed that the full-length Aβ1-42 vaccine (AN1792) induced an antibody response, had promising efficacy, and the rate of cognitive decline was slower in vaccinated patients than in placebo-treated patients (Gilman, 2005). However, 6% of the treated patients developed meningoencephalitis, an inflammatory response thought to be due to a T-cell-mediated response to full-length Aβ1-42 (Orgogozo, 2003).

[0006] Another known anti-Aβ vaccine, ACI-24, contains a 15-amino acid sequence that has complete identity with human Aβ sequence 1-15 (WO2007 / 068411). This peptide antigen is conjugated to a liposomal carrier for the purpose of stimulating antibodies against Aβ while avoiding meningoencephalitis and hemorrhage (Muhs, 2007, Pihlgren, 2013). The selection of the Aβ1-15 peptide as an antigen was based on the argument that this sequence contains a B cell epitope but lacks the strong T cell response site of full-length Aβ1-42, which was thought to be the cause of unwanted inflammatory responses (Monsonego, 2003). ACI-24 has been shown to act through the simultaneous activation of B cell receptors specific for Aβ1-15 and toll-like receptor 4 (TLR4), the latter of which is activated by the monophosphoryl lipid A (MPLA) adjuvant present in the ACI-24 vaccine (Pihlgren, 2013). B cells are activated to proliferate and produce immunoglobulins (Ig) by cross-linking the Ig receptors on the B cell surface.

[0007] Down syndrome (DS), also known as trisomy 21, is one of the most common causes of intellectual disability, occurring in 1 in 800 newborns. This condition most commonly involves the triplication of chromosome 21 (Belichenko, 2016). The facial features of individuals with DS are characteristic, and they have deficiencies in the immune and endocrine systems and delayed cognitive development. A major improvement in the medical understanding of the condition has not only improved the quality of life of DS patients but also significantly extended their lifespan. Currently, the mortality rate of DS patients is equivalent to that of those with other intellectual disabilities until the age of 35. However, after the age of 35, the mortality rate doubles every 6.4 years in DS patients, compared to every 9.6 years in non-DS people. The average life expectancy of the general population in the United States is 79 years, while that of DS patients is 60 years.

[0008] An important characteristic of adult subjects with DS is an increased risk of developing clinical symptoms similar to Alzheimer's disease (AD), characterized by a decline in specific cognitive domains that suggest a diagnosis of dementia. Almost all subjects with DS over the age of 40 show neuropathological changes similar to AD in the form of senile plaque formation and neurofibrillary changes (Head, 2012). It is well accepted that the neuropathology of AD-like cognitive decline includes β-amyloid (Aβ) peptide deposition and subsequent plaque formation, neurofibrillary changes, vascular damage, neuroinflammation, and finally neuronal death. The gene for amyloid protein precursor (APP), which encodes the precursor protein of Aβ, is located on chromosome 21. In subjects with DS, the entire chromosome 21 or at least a part of it is present in triplicate. As a result, the gene encoding APP becomes 3 copies, leading to excessive production of Aβ. Increased Aβ protein production has been shown to correlate with AD-like symptoms in DS subjects and in the general population that develops AD (Head, 2012). These findings conclusively demonstrate that overexpression of wild-type APP throughout life leads to cognitive decline in subjects with DS in a manner similar to the amyloid cascade hypothesis used to explain subjects with AD. Down syndrome-related Alzheimer's disease is characterized by the presence of neuropathological hallmarks of Alzheimer's disease (including in particular cerebral amyloid plaque accumulation and neurofibrillary changes), which can manifest clinical symptoms such as cognitive decline and functional impairment when the brain lesions are fully developed.

[0009] Cognitive decline in DS subjects occurs over several years prior to dementia diagnosis. Cognitive decline is classified into three categories: mild, moderate, and severe. Mild cognitive decline is often characterized by significant memory loss that affects daily life as well as behavioral changes. Moderate cognitive decline is further characterized by increased memory loss going back in time, significant personality changes due to agitation and confusion, changes in sleep patterns, and the need for assistance with daily life. Severe cognitive decline can mean the loss of the ability to communicate, a severe decline in physical ability, and the need for full-time assistance with routine daily tasks. Symptoms such as apraxia and agnosia, as well as changes in personality and behavior, have been reported in 28% of DS subjects by age 30 (Head, 2012). Early Aβ deposition may be associated with episodes termed mild cognitive impairment and / or a slight decline in executive function (Hartley, 2017). Recent studies using the positron emission tomography tracer [11C] Pittsburgh Compound B (PiB) to measure brain amyloid burden in DS subjects have shown that overall amyloid-β increases are associated with declines in verbal episodic memory, visual episodic memory, executive function, and fine motor processing speed. DS subjects who were consistently PiB+ showed worsening episodic memory, while those who were consistently PiB− demonstrated stability or improvement in their abilities (Hartley, 2017). Diagnosis of cognitive decline is difficult in the DS population because it can present with symptoms similar to those of intellectual disability, and improved diagnostic methods are under investigation. Complicating the difficulty of diagnosis is the fact that early symptoms do not appear uniformly. For example, memory loss, while an important early clinical symptom of dementia onset, is not consistent in the DS population.

[0010] Current treatments for cognitive decline in DS are very limited, and most research has focused on dementia or AD. Treatments that have been investigated and shown promise for these indications, such as cholinesterase inhibitors, are currently of limited effectiveness in DS subjects experiencing cognitive decline (Prasher, 2002). In contrast to AD, the effort to target Aβ with immunotherapy in DS has not been extensive.

[0011] WO2013 / 044147 and Belichenko (2016) describe vaccination of Ts65Dn mice, a model of DS, with a vaccine that includes Aβ1-15 peptide encapsulated in liposomes. SUMMARY OF THE INVENTION

[0012] DESCRIPTION OF THE INVENTION The present invention resulted from clinical trials of the ACI-24 vaccine, which includes an anti-alpha beta (anti-Aβ) antigen (including amino acids 1-15 of the human Aβ sequence) and the MPLA adjuvant in a liposomal formulation. The vaccine was able to induce anti-alpha beta antibody titers in two of the highest doses tested (300 μg and 1000 μg of antigen) in human subjects with AD (mild to moderate AD) without inducing serious adverse events (SAEs) associated with the test treatment (investigational product). More specifically, the vaccine was able to induce anti-alpha beta antibody titers in human subjects with AD (mild to moderate AD) when administered 300 μg and 1000 μg of antigen, along with the following clinical observations: · At all test doses, safety was considered good in the trial; · No SAEs associated with the test treatment were observed; · No signal of CNS inflammation or other serious adverse responses to the vaccine; · No ARIA-E and ARIA-H were observed (1 microlesion with a low signal of a hemosequence suspicious for microbleeds (possibility of artifactual result) at a 100 μg dose of ACI-24 in 1 AD patient); · No signs of meningoencephalitis onset; · No observations of T cell activation and induction of inflammatory cytokines.

[0013] Similarly, the vaccine was able to induce anti-a beta antibody titers at both tested doses (300 μg and 1000 μg of antigen) without inducing serious adverse events (SAEs) associated with the test treatment (investigational product) in human subjects with DS. More specifically, the vaccine was able to induce anti-a beta antibody titers in human subjects with DS when administered 300 μg and 1000 μg of antigen, along with the following clinical observations: early response expression (the first increase in titer was observed at week 4) and a boosting effect over time (measured by Meso Scale Discovery (MSD) immunoassay): · To date, safety was considered good in the tests at all tested doses; · No reports of SAEs; · No signals of CNS inflammation or other serious adverse responses to the vaccine; · No observed ARIA-E and ARIA-H; · No signs of the onset of encephalitis; · No observed T cell activation and induction of inflammatory cytokines to date.

[0014] Accordingly, the present invention is a method for inducing an anti-Aβ immune response in a human subject without inducing serious adverse events (i.e., SAEs caused by the treatment), comprising administering to the human subject a. a β-amyloid (Aβ)-derived peptide antigen presented on the surface of a liposome consisting essentially of or consisting of amino acids 1-15 of Aβ b. an adjuvant comprising monophosphoryl lipid A (MPLA) in the form of a liposome vaccine composition, wherein the β-amyloid (Aβ)-derived peptide antigen is administered in an amount of 300-2000 μg, provides a method.

[0015] Such a method can also be represented in the form of a medical use. Accordingly, the present invention also relates to a liposome vaccine composition for use in inducing an anti-Aβ immune response in a human subject without inducing serious adverse events (i.e., SAEs caused by the treatment). a. A β - amyloid (Aβ) - derived peptide antigen presented on the surface of liposomes that contain, consist essentially of, or consist of amino acids 1 - 15 of Aβ b. An adjuvant containing monophosphoryl lipid A (MPLA) There is also provided a liposomal vaccine composition comprising the above, wherein the Aβ - derived peptide antigen is administered in an amount of 300 - 2000 μg.

[0016] Similarly, the present invention relates to the use in the manufacture of a medicament for inducing an anti - Aβ immune response in a human subject without inducing a serious adverse event (i.e., an SAE caused by the treatment). a. A β - amyloid (Aβ) - derived peptide antigen presented on the surface of liposomes that contain, consist essentially of, or consist of amino acids 1 - 15 of Aβ b. An adjuvant containing monophosphoryl lipid A (MPLA) There is provided the use of a liposomal vaccine composition comprising the above, wherein the Aβ - derived peptide antigen is administered in an amount of 300 - 2000 μg.

[0017] All embodiments herein, however expressed, apply to such methods or medical uses.

[0018] As introduced above and as further detailed herein, the liposome compositions of the present invention have been shown to be safe for administration to human subjects. The compositions are safe when administered in a dosage that produces a beneficial anti-Aβ immune response. Safety is measured in accordance with the absence of any serious adverse events attributable to the administration of the liposome vaccine composition. "Serious adverse event" or "SAE" can be defined as any adverse event or adverse reaction that is fatal, life-threatening, requires hospitalization or prolongation of current hospitalization, results in persistent or significant disability or incapacity, or is a congenital anomaly or congenital deficiency. "Life-threatening" in the definition of serious adverse event refers to an event where the subject was at risk of death at the time of the event. Events that are more severe and hypothetically may have led to death are not considered. Serious adverse events / responses that are not immediately life-threatening or do not result in death or hospitalization but are significant enough to endanger the subject or require intervention to prevent one of the other outcomes listed in the above definition should also be considered severe. Although medical judgment is required for the interpretation of such events, the treating physician participating in the human clinical trial can determine whether a serious adverse event has occurred during the clinical trial and whether it is related to the administration of the liposome vaccine composition. To avoid doubt, it is possible for a serious adverse event to occur in a subject that is not related to (not induced or caused by) the administration of the liposome vaccine composition. This is not precluded by the present invention.

[0019] Specific SAEs not induced when administering the liposome compositions of the present invention are · CNS inflammation or other serious unwanted responses to the vaccine; · ARIA-E and ARIA-H; · Meningoencephalitis; · T cell activation and induction of inflammatory cytokines including.

[0020] In the context of the liposome composition of the present invention, "T cell activation" means Aβ-specific T cell activation. As described above, in a previous study (Orgogozo, 2003), some patients exhibited an inflammatory response thought to be due to a T cell-mediated response to full-length Aβ1-42. This T cell-mediated response to full-length Aβ1-42 is avoided using the liposome composition of the present invention based on Aβ1-15. Aβ-specific T cell activation can be evaluated using enzyme-linked immunospot (ELISpot), a type of assay focused on the quantitative measurement of the frequency of cytokine secretion by single cells.

[0021] Amyloid-related imaging abnormalities (ARIA) are abnormal signals seen in neuroimaging of Alzheimer's disease patients associated with amyloid-modifying therapy. ARIA-E refers to cerebral edema, including disruption of the tight endothelial junctions of the blood-brain barrier followed by fluid accumulation. ARIA-H refers to microhemorrhages (mH) of the brain, which are small brain hemorrhages often accompanied by hemosiderin deposition.

[0022] There may be no serious adverse events (SAEs) during the period when the liposome vaccine composition is administered. There may be no SAEs for an appropriate period after administration of the final liposome vaccine composition. For example, there may be no SAEs 12 weeks, 24 weeks, 36 weeks, or 48 weeks, or 1 year, 2 years, or 3 years after administration of the final liposome vaccine composition.

[0023] Unless otherwise specified, the dosages indicated here relate to the single-dose amount of the β-amyloid (Aβ)-derived peptide antigen in the liposome vaccine composition. Thus, in ACI-24, the dosage, unless otherwise specified, is represented with reference to the tetra-palmitoylated A beta 1-15 described here and also in SEQ ID NO: 1: SEQ ID NO: 1 - Tetra-palmitoylated A beta 1-15 H-Lys(palmitoyl)-Lys(palmitoyl)-Asp-Ala-Glu-Phe-Arg-His-Asp-Ser-Gly-Tyr-Glu-Val-His-His-Gln-Lys(palmitoyl)-Lys(palmitoyl)-OH

[0024] When specific values are specified, these values are subject to manufacturing tolerances as would be recognized by one of ordinary skill in the art. Generally, the specified dosages cover a 15% variation on either side of the indicated value. For example, a dosage of a β-amyloid (Aβ)-derived peptide antigen specified as 1000 μg includes 850 - 1150 μg of the β-amyloid (Aβ)-derived peptide antigen. The liposomal vaccine compositions described herein were safe when the β-amyloid (Aβ)-derived peptide antigen was administered in an amount of 10 - 1000 μg. However, in order to elicit an anti-Aβ immune response, a dosage of at least 300 μg was required. The two highest dosages administered (300 μg and 1000 μg) resulted in a measurable anti-Aβ immune response. The response may have been dose-dependent. The term "anti-Aβ immune response" refers to the production of anti-Aβ antibodies that bind to Aβ in a human subject in response to administration of the liposomal vaccine composition. The response may, therefore, also be referred to as an anti-Aβ antibody response. The antibodies may include antibodies of the IgM isotype. The antibodies preferably include antibodies of the IgG isotype. The antibody response is generally polyclonal. This response can be measured in a suitable sample taken from a human subject, such as a serum-containing sample. Therefore, the sample may include or be derived from a blood sample. The antibodies preferably bind to the pathological form of Aβ, as defined as Aβ in a form that includes β-sheet multimers. The antibodies produced are, therefore, referred to as "Aβ-specific" antibodies. The anti-Aβ immune response can be measured by any suitable method such as ELISA. For example, the anti-Aβ immune response can be measured by a method in which Aβ, such as Aβ1 - 42, is coated on a solid support and a sample from a human subject is applied thereto. A secondary antibody can be used to detect the binding of antibodies from the sample to the immobilized Aβ. Such a method can be quantitative. The secondary antibody can be an anti-Ig antibody, thereby enabling the detection of all isotypes. The secondary antibody can be an anti-IgG antibody. Thereby, it may be possible to measure the Aβ-specific IgG titer.

[0025] Thus, according to all aspects of the present invention, the β-amyloid (Aβ)-derived peptide antigen (the dosage is represented for the tetra-palmitoylated A beta 1-15 shown in SEQ ID NO: 1) is administered in an amount of 300 to 2000 μg. This dosage combines safety (no SAE induction) and the ability to produce an anti-Aβ immune response. At the highest dosage tested, the anti-Aβ immune response increased and safety was maintained, so a high dosage within this range may be advantageous. For example, according to one embodiment, the β-amyloid (Aβ)-derived peptide antigen is administered in an amount of 500 to 2000 μg, preferably 1000 to 1500 μg. In one embodiment, the β-amyloid (Aβ)-derived peptide antigen (the dosage is represented for the tetra-palmitoylated A beta 1-15 shown in SEQ ID NO: 1) is administered in an amount of 1000 μg. In a preferred embodiment, the β-amyloid (Aβ)-derived peptide antigen of SEQ ID NO: 1 (tetra-palmitoylated A beta 1-15) is administered in an amount of 300 to 2000 μg.

[0026] As will be readily appreciated by those skilled in the art, the dosage may alternatively be expressed with reference to the corresponding amount of A beta 1-15 alone (i.e., without lysine residues and palmitoylation), described herein and also in SEQ ID NO: 2: SEQ ID NO: 2 - A beta 1-15 H-Asp-Ala-Glu-Phe-Arg-His-Asp-Ser-Gly-Tyr-Glu-Val-His-His-Gln-OH

[0027] Thus, according to one aspect of the present invention, a β-amyloid (Aβ)-derived peptide antigen (the dosage is represented for A beta 1-15 shown in SEQ ID NO: 2) is administered in an amount of 152 to 1016 μg (corresponding to 300 to 2000 μg of the tetra-palmitoylated A beta 1-15 shown in SEQ ID NO: 1). This dosage satisfies safety (no SAE induction) and the ability to produce an anti-Aβ immune response. At the highest dosage tested, the anti-Aβ immune response increased and safety was maintained, so a high dosage within this range may be advantageous. For example, according to one embodiment, a β-amyloid (Aβ)-derived peptide antigen (the dosage is represented for A beta 1-15 shown in SEQ ID NO: 2) is administered in an amount of 255 to 1016 μg, preferably 510 to 767 μg. In one embodiment, a β-amyloid (Aβ)-derived peptide antigen (the dosage is represented for A beta 1-15 shown in SEQ ID NO: 2) is administered in an amount of 130 to 177 μg, preferably 152 μg. In one embodiment, a β-amyloid (Aβ)-derived peptide antigen (the dosage is represented for A beta 1-15 shown in SEQ ID NO: 2) is administered in an amount of 432 to 588 μg, preferably 510 μg. In one embodiment, a β-amyloid (Aβ)-derived peptide antigen (the dosage is represented for A beta 1-15 shown in SEQ ID NO: 2) is administered in an amount of 510 μg. In one embodiment, the β-amyloid (Aβ)-derived peptide antigen of SEQ ID NO: 2 is administered in an amount of 152 to 1016 μg.

[0028] Additional beneficial effects observed upon administration of the liposomal vaccine composition of the invention at a specified dosage include a dosage-dependent decrease in brain amyloid load (measured by PET, see Figure 1), improvement in cognition measured by the Mini-Mental State Examination (MMSE) during the treatment period (Figure 2), and improvement in cognition / function measured by CDR-SB during the treatment period (Figure 3). The Mini-Mental State Examination (MMSE) (Folstein 1975) is well-known in the art; it is most commonly used to test for complaints of memory or other intellectual problems, helps physicians detect cognitive impairment, and helps evaluate its progression and severity. It consists of a series of questions and tests, each of which is scored if answered correctly. The MMSE tests a number of different intellectual abilities, including a person's memory, attention, and language. The score ranges from 0 to 30, with 30 being the best possible score and 0 being the worst. As shown in Figure 2, when the β-amyloid (Aβ)-derived peptide antigen was administered in an amount of 1000 μg, the MMSE improved during the treatment period. It should be noted that the study was not based on this specific parameter.

[0029] The Clinical Dementia Rating scale or CDR scale is a numerical scale used to quantify the severity of symptoms of AD (i.e., its 'disease stage'). The system was developed at the Washington University School of Medicine (Hughes et al 1982) and involves certified healthcare providers who evaluate the cognitive and functional abilities of human subjects by semi-structured interview in six domains: memory, orientation, judgment and problem-solving, community affairs, home and hobbies, and personal care. The scores for each of these are combined to yield a total score in the range of 0 (asymptomatic) to 3 (severe), referred to as the item total score (CDR-SB). The CDR-SB score thus ranges from 0 to 18 points. As shown in Figure 3, when the β-amyloid (Aβ)-derived peptide antigen was administered in an amount of 1000 μg, there was a relative improvement in CDR-SB during the treatment period. It should be noted that the study was not based on this specific parameter.

[0030] Further beneficial effects observed by administration of the liposomal vaccine composition of the present invention at a specified dose to DS subjects include early response expression with an increase in anti-Aβ antibody titer as early as 4 weeks, early IgG titers compared to AD patients (by the AD test described in Example 1), time-course observation of the boost effect (measured by, for example, Meso Scale Discovery immunoassay), and consistent responses in the majority of the highest-dose patients (measured by, for example, Meso Scale Discovery immunoassay).

[0031] The Aβ-derived peptide antigen is presented on the outer surface of the liposome. This is generally by insertion into the outer surface of the liposome. Insertion into the outer surface of the liposome can be facilitated via binding of the Aβ-derived peptide antigen to a moiety inserted into the outer surface of the liposome. The liposome can be any liposome suitable for presenting the Aβ-derived peptide antigen on the surface. Generally, the moiety includes a hydrophobic moiety to ensure insertion into the lipid bilayer of the liposome. The moiety can be any suitable moiety, but is preferably a fatty acid. Thus, in a preferred embodiment, the β-amyloid (Aβ)-derived peptide antigen is lipidated. The fatty acid can include a palmitoyl residue. Therefore, the β-amyloid (Aβ)-derived peptide antigen may be palmitoylated. A preferred construct is the Aβ-derived peptide antigen (Aβ(1-15)) bound to two palmitoyl residues in the N and C terminal regions of the peptide. Thus, the peptide antigen is tetra-palmitoylated. This can be facilitated by incorporation of two amino acid residues such as lysine into the N and C terminal regions of the Aβ-derived peptide antigen. Amino acid residues such as lysine are palmitoylated.

[0032] In one embodiment, the liposome has a negative surface charge; the liposome is anionic. Preferably, the liposome comprises a phospholipid, and more preferably still, the phospholipid comprises dimyristoyl phosphatidyl-choline (DMPC) and dimyristoyl phosphatidyl-glycerol (DMPG). The liposome may further comprise cholesterol. The molar ratio of these three components may be 9:1:7 in one embodiment.

[0033] Therefore, the most preferred configuration comprises an Aβ-derived peptide antigen reconstituted in the liposome. Thus, these compositions of the present invention may generally be referred to herein as "the liposomal vaccine compositions of the present invention".

[0034] The Aβ-derived peptide antigen induces a B cell response in a subject. It is a "B cell antigen". B cells are activated and proliferate, and produce immunoglobulin (Ig) by cross-linking the Ig receptors on the B cell surface. As already explained, Aβ plaques are formed by Aβ peptides 39-43 amino acids in length that are in a random coil form in their native non-pathological form. During the transition to a pathological state, they are mainly converted to a β-sheet secondary structure and spontaneously aggregate into insoluble deposits. Therefore, the Aβ-derived peptide antigen is herein defined as a peptide antigen that is derived from (human) Aβ's (maximum) 43 amino acids but is not the full-length Aβ. More specifically, the Aβ-derived peptide antigen contains the immunodominant B cell epitope of Aβ(1-42) but lacks the T cell epitope found in Aβ(1-42). The Aβ-derived peptide antigen comprises, consists essentially of, or consists of 15 contiguous amino acids from the N-terminal 17 amino acids of Aβ. It should be noted that the Aβ-derived peptide antigen can be provided in relation to a large peptide molecule, the remainder of which is not derived from the Aβ amino acid sequence. For example, the peptide may contain additional residues such as lysine residues to facilitate palmitoylation. Such residues are generally found at the N and C termini of the peptide. In this specification, the term "consists essentially of" means that the Aβ-derived peptide antigen contains 15 contiguous amino acids from the N-terminal 17 amino acids of Aβ but may contain a certain number of additional residues such as lysine residues to facilitate palmitoylation. The Aβ-derived peptide antigen comprises, consists essentially of, or consists of amino acids 1-15 of Aβ, which may be referred to as "Aβ(1-15)" (WO2007 / 068411, ACI-24).

[0035] The Aβ-derived peptide antigen comprised in the composition of the present invention adopts a secondary structure that mimics the pathological form of Aβ. Preferably, the Aβ-derived peptide antigen adopts a secondary structure that includes a β-sheet form. Even more preferably, the Aβ-derived peptide antigen mainly adopts a β-sheet form when presented on the surface of a liposome.

[0036] The Aβ-derived peptide antigen contained in the composition of the present invention is a synthetic peptide. In certain embodiments, the Aβ-derived peptide antigen is produced by chemical synthesis.

[0037] The liposomal vaccine composition contains at least one monophosphoryl lipid A (MPLA) adjuvant. Lipid A-based adjuvants are derived from lipopolysaccharides (chemically modified to reduce toxicity) and have been proven to be safe and effective. The MPLA adjuvant used herein is preferably synthetic monophosphoryl lipid A (MPLA). As defined herein, the term MPLA refers to monophosphoryl hexa-acyl lipid A, 3-deacyl (synthetic) (3D-(6-acyl)PHAD (登録商標) ), PHAD (登録商標) (phosphorylated hexa-acyl disaccharide) and MPLA derivatives such as MPL. The MPLA adjuvant can be a toll-like receptor (TLR) agonist, particularly a TLR4 agonist. The purpose of the adjuvant is to increase or stimulate the immune response in a subject. Preferably, at least one MPLA adjuvant forms part of the liposome; it can form part of the lipid bilayer. The MPLA adjuvant can be presented, at least in part, on the outer surface of the liposome; this can be the result of the adjuvant forming part of at least the outer layer of the lipid bilayer. The liposome can function efficiently as an adjuvant due to the loading of monophosphoryl lipid A (MPLA). The MPLA adjuvant generally forms part of the outer layer of the liposome. MPLA is generally added during liposome formation (further described herein). Thus, a preferred liposome contains dimyristoyl phosphatidyl-choline (DMPC), dimyristoyl phosphatidyl-glycerol (DMPG), cholesterol, and MPLA. The molar ratio of these four components can be 9:1:7:0.05 in certain embodiments.

[0038] In certain embodiments of the present invention, the compositions of the present invention comprise two different adjuvants. Additional adjuvants that may be used in accordance with the present invention include, among others, aluminum hydroxide (Alum) and / or CpG. In certain embodiments, one or more MPLA adjuvants that form part of the liposome can be combined with an encapsulated adjuvant. In other embodiments, when forming the liposome, one or more MPLA adjuvants that form part of the liposome can be mixed with an additional adjuvant (e.g., Alum or CpG).

[0039] The MPLA adjuvant can be mixed with the composition in a dose that correlates with the dose of the β-amyloid (Aβ)-derived peptide antigen. Thus, for example, a liposomal vaccine composition in which the β-amyloid (Aβ)-derived peptide antigen (the dose is expressed for the tetra-palmitoylated A beta 1-15 shown in SEQ ID NO: 1) is administered in an amount of 1000 μg (which can be 850 - 1150 μg considering manufacturing tolerances) can include the MPLA adjuvant administered in an amount of 175 μg (which can be 50 - 300 μg considering manufacturing tolerances) or in an amount of 225 μg (which can be 150 - 300 μg considering manufacturing tolerances). Similarly, a liposomal vaccine composition in which the β-amyloid (Aβ)-derived peptide antigen (the dose is expressed for the tetra-palmitoylated A beta 1-15 shown in SEQ ID NO: 1) is administered in an amount of 300 μg (which can be 255 - 345 μg considering manufacturing tolerances) can include the MPLA adjuvant administered in an amount of 52.5 μg (which can be 15 - 90 μg considering manufacturing tolerances) or in an amount of 67.5 μg (which can be 45 - 90 μg considering manufacturing tolerances). The MPLA adjuvant can be administered in an amount of 15 - 600 μg. This dosage contributes to the safety and efficacy of the liposomal vaccine composition (in terms of the ability to produce an anti-Aβ immune response). By certain embodiments, the MPLA adjuvant is administered in an amount of 50 - 600 μg, preferably 150 - 450 μg. In certain embodiments, the MPLA adjuvant is administered in an amount of 175 μg. When specific values are specified, these values are subject to manufacturing tolerances as would be recognized by those skilled in the art. Generally, the specified dosage of the MPLA adjuvant covers a variation of about 71% to either side of the indicated value. In other embodiments, based on the development of a narrow concentration range of MPLA stock solution, the MPLA adjuvant can be administered in an amount of 45 - 600 μg. This dosage also contributes to the safety and efficacy of the liposomal vaccine composition (in terms of the ability to produce an anti-Aβ immune response). By certain embodiments, the MPLA adjuvant is administered in an amount of 150 - 600 μg, preferably 200 - 450 μg. In certain embodiments, the MPLA adjuvant is administered in an amount of 225 μg. For these embodiments, when specific values are specified, these values are also subject to manufacturing tolerances as would be recognized by those skilled in the art.Generally, the dosage of the identified MPLA adjuvant covers an approximately 33% variation to either side of the indicated value.

[0040] The liposomal vaccine composition of the present invention can be synthesized by known means. See, for example, WO2005 / 081872, WO2012 / 020124, WO2012 / 055933 and WO2013 / 044147 (each of which is incorporated herein by reference).

[0041] The liposomal vaccine composition can be administered to a subject by any suitable route of administration. As will be appreciated by those skilled in the art, the vaccine composition can be administered by local, oral, rectal, nasal or parenteral (e.g., intravenous, intradermal, subcutaneous or intramuscular) routes. Further, the vaccine composition may be incorporated into a sustained release matrix such as a biodegradable polymer, and the polymer is implanted in proximity or in close proximity to where delivery is desired. However, in a preferred embodiment, the vaccine composition is administered by injection, most preferably intramuscularly or subcutaneously. The typical volume of an injectable dosage form of the liposomal vaccine composition is 0.01 - 10 ml, such as 0.75 - 2.5 ml, preferably about 2.5 ml.

[0042] The liposomal vaccine composition can be administered to a subject once to obtain a protective immune response. However, generally, liposomal vaccine compositions are administered to the same subject multiple times. Thus, a so-called prime-boost regimen can be used according to the present invention. Vaccine administrations are generally separated by an intervening period of at least one week and often about 1 to 12 months. Safety and efficacy (in terms of the ability to produce an anti-Aβ immune response) have been confirmed when liposomal vaccine compositions are administered regularly over a long period. In certain embodiments, the liposomal vaccine composition is administered a first time and a second time 1 to 4 weeks later. The liposomal vaccine composition may be administered 2, 3, 4, 5, 6, 7, 8, 9, 10 times or more if there is an appropriate interval between administrations. The liposomal vaccine composition may be administered 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12 times during a 12-month period if there is an appropriate period between administrations. The liposomal vaccine composition may be administered indefinitely if there is an appropriate interval between administrations. Appropriate intervals are generally at least one week and often about 1 to 12 months. The interval can be based on monitoring of the individual subject. Monitoring can include monitoring the disease state of the subject over time and / or monitoring the immune response level of the subject. Tests that allow tracking of the disease course (e.g., MMSE, amyloid PET scan or anti-Aβ immune response) are described herein. In prophylactic applications, the liposomal vaccine composition may be administered less frequently compared to a therapeutic method and may be administered according to a regular schedule. In a prophylactic method, monitoring can be used. For example, in a subject at risk of developing a condition characterized by or associated with an amyloid-beta related disease or condition or loss of cognitive memory ability.Appropriate tests and biomarkers are described herein, including monitoring of cerebral A beta levels using amyloid PET scans (which may not be present in early prevention), monitoring of AD progression biomarkers such as tau, phosphorylated tau, and A beta levels (Aβ1-42 and Aβ1-40) in blood and / or CSF, neurofilament light chain in blood and / or CSF, measurement of effectiveness against clinical / cognitive parameters, and measurement of immune responses in serum and / or CSF including but not limited to blood anti-A beta 1-42 IgM titer and / or anti-A beta 1-42 IgG titer.

[0043] When a vaccination regimen is herein defined for a period, the administration of the initial liposomal vaccine composition is considered as time 0. In certain embodiments, the liposomal vaccine composition is administered every 4 - 12 weeks for at least 48 weeks. For example, the liposomal vaccine composition can be administered every 4 weeks for 12 weeks and then every 12 weeks for at least 36 weeks. Thus, this includes four separate administrations of the liposomal vaccine composition at week 0, 4, 8, and 12, followed by three separate administrations of the liposomal vaccine composition at week 24, 36, and 48. Depending on the overall administration regimen, the liposomal vaccine composition may be further administered at a later time point as needed. Generally, this is after completion of the initial administration schedule (the "schedule"). Thus, it can be referred to as a "booster" administration. Such further administrations can be made at appropriate intervals after completion of the initial administration schedule; for example, 4, 12, 24, 26, 36, or 48 weeks after the final administration according to the schedule or longer such as 1 year, 2 years, 2.5 years, 3 years, 3.25 years, 3.5 years, 4 years, 5 years or more after the final administration according to the schedule.

[0044] As already shown, the liposomal vaccine composition induces an anti-Aβ immune response in a human subject without inducing a serious adverse event. The liposomal vaccine composition can be administered to a human subject for the treatment, prevention, induction of a protective immune response, or reduction of symptoms associated with an amyloid-beta related disease or condition or a condition characterized by or associated with loss of cognitive memory function. The liposomal vaccine composition can, therefore, be administered to a human subject for both prophylactic and therapeutic purposes.

[0045] The amyloid-beta related disease or condition can be a neurological disorder, such as (and in particular) Alzheimer's disease (AD). Other examples of amyloid-beta related diseases or conditions according to the present invention include mild cognitive impairment (MCI), Down syndrome (DS) including Down syndrome-related Alzheimer's disease, cardiac amyloidosis, cerebral amyloid angiopathy (CAA), multiple sclerosis, Parkinson's disease, Lewy body dementia, ALS (amyotrophic lateral sclerosis), adult-onset diabetes, inclusion body myositis (IBM), ocular amyloidosis, glaucoma, macular degeneration, lattice dystrophy, and optic neuritis. Many of these conditions are characterized by or associated with loss of cognitive memory function. Therefore, the conditions characterized by or associated with loss of cognitive memory function according to the present invention include AD, mild cognitive impairment (MCI), Down syndrome including Down syndrome-related Alzheimer's disease, cardiac amyloidosis, cerebral amyloid angiopathy (CAA), multiple sclerosis, Parkinson's disease, Lewy body dementia, ALS (amyotrophic lateral sclerosis), and inclusion body myositis (IBM).

[0046] Accordingly, the present invention relates to the treatment and prevention of an amyloid-beta related disease or condition or a condition characterized by or associated with loss of cognitive memory function, including administering the vaccine of the present invention. An amyloid-beta related disease or condition or a condition characterized by or associated with loss of cognitive memory function includes Alzheimer's disease, mild cognitive impairment (MCI), Down syndrome (DS) including Down syndrome-related Alzheimer's disease, cardiac amyloidosis, cerebral amyloid angiopathy (CAA), multiple sclerosis, Parkinson's disease, Lewy body dementia, ALS (amyotrophic lateral sclerosis), adult-onset diabetes, inclusion body myositis (IBM), ocular amyloidosis, glaucoma, macular degeneration, lattice dystrophy and optic neuritis, preferably Alzheimer's disease (AD), Down syndrome (DS) and Down syndrome-related Alzheimer's disease.

[0047] With respect to AD, it has been recognized that intervention as early as possible in the onset of cognitive impairment may be most effective. Accordingly, prophylactic administration may be advantageous, particularly in the presence of other risk factors. In such embodiments, the human subject prior to treatment may exhibit absence of cognitive impairment corresponding to a Mini-Mental State Examination (MMSE) score of about 30. To avoid misunderstanding, this score indicates the absence of cognitive impairment.

[0048] Furthermore, administration to human subjects having early AD may also be beneficial. In certain embodiments, the human subject prior to treatment exhibits cognitive impairment corresponding to a Mini-Mental State Examination (MMSE) score of at least 18 (thus 18 - 30), for example 18 - 28, preferably at least 20 (thus 20 - 30), for example 20 - 28. In certain embodiments, the human subject has AD, particularly early AD. Such a subject may exhibit cognitive impairment corresponding to an MMSE score of at least 20. Early AD includes mild cognitive impairment due to AD and mild AD. In certain embodiments, the human subject has mild AD. Such a subject may exhibit cognitive impairment corresponding to an MMSE score of 20 - 28. In other embodiments, the subject does not have severe (late stage) AD. In further embodiments, the human subject has early AD, mild AD, mild to moderate AD or moderate AD. Such a subject may exhibit cognitive impairment corresponding to an MMSE score of at least 12.

[0049] In a specific embodiment, the human subject has mild to moderate AD. Such a subject may exhibit cognitive impairment corresponding to an MMSE score of 12 - 28. In a specific embodiment, the human subject has moderate AD. Such a subject may exhibit cognitive impairment corresponding to an MMSE score of 12 - 19.

[0050] Other factors that may be included in the selection of the treatment subject include age. For example, the subject may be over 40 years old.

[0051] As previously described, an important characteristic of adult subjects with DS is an increased risk of developing clinical symptoms similar to Alzheimer's disease (AD), characterized by a decline in specific cognitive domains that suggests a diagnosis of dementia in the most advanced disease stage. Nearly all subjects with DS over 40 years of age exhibit neuropathological changes similar to AD in the form of amyloid plaque formation and neurofibrillary tangles (Head, 2012). Thus, when referring specifically herein to the treatment, prevention, induction of a defensive immune response, or alleviation of symptoms associated with DS, it is intended to relate to AD-like symptoms in DS subjects. Preventive treatment can be applied to subjects without evidence of beta-amyloid plaque formation and neurofibrillary tangles. As previously described, studies using the positron emission tomography tracer [11C] Pittsburgh Compound B (PiB) to measure brain amyloid burden in DS subjects have shown that overall amyloid-β increases correlated with declines in verbal episodic memory, visual episodic memory, executive function, and fine motor processing speed. DS subjects who were consistently PiB+ showed deterioration of episodic memory, while those who were consistently PiB− demonstrated stability or improvement in their abilities (Hartley, 2017). Thus, preventive treatment can be applied to subjects who are PiB−. Conversely, therapeutic treatment can be applied to subjects with evidence of beta-amyloid plaque formation and / or neurofibrillary tangles and / or those who are PiB+. DS is a population with an increased risk of AD-like diseases. It provides an opportunity to investigate effective treatments for AD that would be beneficial to both the DS population and the general population. The homogeneity of the etiology, age-related disease onset, and the absence of other dementias strongly enable preventive trials of AD-like symptoms in DS. The focus for DS subjects is preventive treatment. Biomarker endpoints of Alzheimer pathology can be employed for monitoring treatment. Examples include plasma and / or CSF A-beta levels, total tau, phosphorylated tau protein, soluble amyloid precursor protein alpha (sAPPα), soluble amyloid precursor protein beta (sAPPβ), orexin A, neurofilament light chain (NfL), inflammatory cytokines, angiogenic proteins, and vascular injury markers, and TLR-4 expression can be employed for monitoring treatment.Positron emission tomography (PET) tracers such as [11C] Pittsburgh compound B (PiB), florbetapir, or florbetaben (Hartley, 2017) for measuring brain amyloid load in the DS population and potentially tau PET tracers such as florotaucipir or PI-2620 may also be used in PET scanning imaging. Free, total, and complexed IgG titers can be measured. Free, total, and complexed IgM titers can be measured. Clinical effectiveness can be measured using, in particular, the Clinical Global Impression of Change (CGIC) and / or cognitive tests (e.g., Cambridge Neuropsychological Test Automated Battery (CANTAB) motor control, reaction time, paired associate learning, Cued Recall Test (CRT), Cambridge Cognitive Test - Down syndrome (CAMCOG-DS), Modified Selective Reminding Test (SRT), NEPSY-II - Train and Car Subtests, Kaufman Brief Intelligence Test Second Edition (KBIT-2)); Brief Psychiatric Rating Scale (BPRS-4), behavior (e.g., Vineland Adaptive Behavior Scale (VABS), Neuropsychiatric Inventory (NPI), and assessment of progression to dementia (e.g., Dementia Screening Questionnaire for Individuals with Intellectual Disabilities (DSQIID)).

[0052] In a human subject with DS, assessment by MMSE may not be appropriate. Similarly, age considerations may vary (for example, due to a short life expectancy). Male or female subjects with DS may be treated prophylactically at any age, particularly. As already described, prophylactic treatment may be applicable to subjects without evidence of beta-amyloid plaque formation and neurofibrillary changes. Conversely, therapeutic treatment may be applicable to subjects with evidence of beta-amyloid plaque formation and neurofibrillary changes. A human subject with DS may be in the preclinical stage of AD without amyloid-related cognitive decline. The subject to be treated may be under 50 years old, for example, 45, 40, 35, 30, or under 25 years old. A human subject with DS who can be treated may be identified as having mild to moderate intellectual disability using the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) classification. DSM-5 is the 2013 revised edition of the Diagnostic and Statistical Manual of Mental Disorders, a classification and diagnostic tool published by the American Psychiatric Association (APA). In the United States, DSM serves as the primary authority for mental diagnosis.

[0053] According to certain embodiments, a human subject who can be treated may be identified as positive for Aβ deposits by a PET scan. Such Aβ deposits are seen in patients with earlier stage AD (mild cognitive impairment due to AD and mild AD) and also more advanced stages of AD such as moderate AD. For example, florbetaben positron emission tomography (PET) may be used to investigate amyloid load in the brain.

[0054] Human subjects who can be treated can be identified based on the CDR score, which can be the CDR-SB score introduced above. A CDR-SB score of 0 can identify the patient as normal. Such subjects can potentially be prophylactically treated in the presence of other risk factors. A CDR-SB score of 0.5 - 2.5 can identify subjects with MCI. A CDR-SB score of 2.5 - 4.0 can identify subjects with very mild AD. A CDR-SB score of 4.5 - 9.0 can identify subjects with mild AD. A CDR-SB score of 9.5 - 15.5 can identify subjects with moderate AD. A CDR-SB score of 16.0 - 18.0 can identify subjects with severe AD. See Bryant et al., Arch Neurol. 2010;67(6):746 - 749. doi:10.1001 / archneurol.2010.115. As previously described, administration to human subjects with early disease (cognitive impairment or AD) can also be beneficial. Thus, in certain embodiments, the human subject prior to treatment exhibits a cognitive impairment corresponding to a CDR-SB score not exceeding 15.5, for example 0.5 - 15.5 or not exceeding 9.0, for example 0.5 - 9.0.

[0055] The human subjects who can be treated can be identified based on the Montreal Cognitive Assessment (MoCA), a 30-question test that takes about 10-12 minutes to complete (Nasreddine ZS, Phillips NA, et al. The Montreal Cognitive Assessment, MoCA: A brief screening tool for mild cognitive impairment. J Am Geriatr Soc. 2005;53:695-699). MoCA assesses various types of cognitive abilities. This includes orientation, short-term memory / delayed recall, executive function / visuospatial ability, language ability; abstraction, animal naming, attention, and clock drawing tests. The MoCA score ranges from 0 to 30, and a score of 26 or above is generally considered normal. In the initial test data establishing MoCA, the average score of normal controls was 27.4, while it was 22.1 for people with mild cognitive impairment (MCI) and 16.2 for subjects with Alzheimer's disease. Thus, a MoCA score of less than 26 can identify subjects as treatable. A score of 26 or above can identify subjects as potentially preventable in the presence of other risk factors. As already described, administration to human subjects with the initial disease may also be beneficial. Thus, in one embodiment, the human subject before treatment exhibits a cognitive impairment corresponding to a MoCA score of 16-26.

Brief Description of the Drawings

[0056]

Figure 1

[0057]

Figure 2

[0058]

Figure 3

[0059]

Table 1

Table 2

[0060] The present invention is further understood with reference to the following non - limiting examples.

[0061] Definition: The MMSE (Folstein 1975) is widely used in a test of overall cognitive function that evaluates memory, orientation, and execution in a short series of tests. The score ranges from 0 to 30, with 30 being the best possible score and 0 being the worst possible score.

[0062] The Clinical Dementia Rating Scale (Hughes et al 1982) is an overall rating of the function of Alzheimer's patients in six categories: memory, orientation, judgment and problem - solving, community problems, home and hobbies, and self - care (since cognition is also confirmed by memory, it is not purely a function - only evaluation). It is based on a semi - structured interview method conducted by an evaluator with the patient and caregiver without evaluating the results of the above - mentioned cognitive tests. The score for each category ranges from 0 (asymptomatic) to 3 (severe), and the sum of these items (total item score) can, therefore, range from 0 to 18 points.

[0063] Early - stage AD patients include mild cognitive impairment due to AD and mild AD (MCI).

[0064] According to the National Institute on Aging - Alzheimer's Association (NIA - AA) criteria, mild cognitive impairment due to Alzheimer's disease is manifested by a clinical picture consistent with the phenotype of AD, which is characterized by a change in cognition from the previously achieved level as indicated by self - or informant report and / or physician judgment, cognitive impairment in at least one domain (but not necessarily episodic memory) compared to age - and education - adjusted normative values (dysfunction in more than one cognitive domain is acceptable), preservation of functional ability independence, no dementia, and no other potentially dementing disorders, and requires evidence of decline within the individual.

[0065] Likely AD dementia according to the NIA - AA criteria meets the criteria for dementia and further has the following main characteristics: insidious onset (symptoms develop gradually over months to years, not suddenly over hours or days), a clear history of cognitive worsening by report or observation; and the initial and most prominent cognitive deficit is demonstrated by history and one of the following category of tests: amnestic type (the most common symptom of AD dementia. The deficit includes impairment in learning and recall of recently learned information). There must also be evidence of cognitive impairment in at least one other cognitive domain); non - amnestic type: language disorder type (the most prominent deficit is anomia, but there must also be deficits in other cognitive domains); visuospatial disorder type: (the most prominent deficit is spatial cognition, including object agnosia, prosopagnosia, simultanagnosia, and alexia; there must also be deficits in other cognitive domains); executive dysfunction (the most prominent deficit is impairment in inference, judgment, and problem - solving. There must also be deficits in other cognitive domains).

[0066] Early - stage AD patients are patients with a MMSE score of at least 20 (20 or more), including patients with mild cognitive impairment due to AD and patients with mild AD.

[0067] Mild AD patients are patients with a MMSE score of 20 - 28.

[0068] Mild - to - moderate AD patients are patients with a MMSE score of 12 - 28.

[0069] Moderate AD patients are those with MMSE scores of 12 - 19.

Example

[0070] Example 1. Safety and Efficacy in Humans in a Phase I / II AD Trial Purpose of the clinical trial : The overall trial objective was to evaluate the safety, immunogenicity, and efficacy of ACI - 24 by repeated dosing at four different dose levels in patients with mild to moderate Alzheimer's disease (AD) diagnosed according to the criteria of the National Institute of Neurological and Communicative Disorders and Stroke - Alzheimer's Disease and Related Disorders Association (NINCDS - ADRDA) and having scores of 18 - 28 on the Mini - Mental State Examination (MMSE) at initial screening.

[0071] Primary purpose: · To evaluate the safety and tolerability of ACI - 24 in patients with mild to moderate Alzheimer's disease. · To evaluate the effects of various doses of ACI - 24 on the induction of anti - Aβ1 - 42 IgG titers in serum.

[0072] Secondary purpose: · To explore the effect of ACI - 24 on the reduction of Aβ levels in the brains of patients with mild to moderate Alzheimer's disease. · To explore the effect of ACI - 24 on T - cell activation. · To explore the effects of ACI - 24 on putative biomarkers of Alzheimer's disease progression such as total tau and phosphorylated tau protein (phospho - tau) and Aβ levels (Aβ1 - 42 and Aβ1 - 40) in blood and CSF. · To explore the efficacy of ACI - 24 on clinical / cognitive endpoints in patients with mild to moderate Alzheimer's disease. · Explore the induction of immune responses in serum and / or CSF, including but not limited to the anti-Aβ1-42 IgM titer in blood. · Explore the induction of inflammatory cytokines in blood.

[0073] Forty-eight patients were randomized into four dose cohorts at a 3:1 active (ACI-24) to placebo (saline) ratio. The investigational drug was administered to the patients seven times, with the first four doses every four weeks and the remaining three doses every twelve weeks. The subcutaneous injection schedule was at weeks 0, 4, 8, 12, 24, 36, and 48, and booster injections were given if optional. Four patients in cohort 3 who consented and were able to receive a single additional 300 μg or placebo booster dose were given the dose 2.5 to 3.25 years after the last injection at visit 16 (V16, week 48, during which the seventh injection was administered) and 6 to 15 months after a two-year safety follow-up. Patients in cohort 4 were given a booster dose of 1000 μg of ACI-24 or placebo 18 months (week 74) after the first administration. The dose cohorts were tested sequentially as follows. · Dose cohort 1: 10 μg antigen or placebo · Dose cohort 2: 100 μg antigen or placebo · Dose cohort 3: 300 μg antigen or placebo · Dose cohort 4: 1000 μg antigen or placebo

[0074] The antigen dose relates to tetrapalmitoylated Aβ1-15 acetate. The vaccine formulation is an injectable suspension (liposome suspension in PBS). The dose cohorts were tested in a sequential manner, and each cohort had completed four immunizations. Safety data, including data two weeks after the fourth injection (i.e., visits 8 and 14), were reviewed by the Data Safety Monitoring Board (DSMB) prior to the start of enrollment in the next cohort. To further enhance safety, an interval of at least one week was planned between the first administrations for the first four subjects in each cohort.

[0075] Inclusion criteria: ·AD that is almost certain according to the NINCDS-ADRDA criteria. · Florbetaben-PET scan consistent with the presence of amyloid pathology at screening. · Mini-Mental State Examination (MMSE) score of 18 - 28 * 。 · Over 40 years old and less than 90 years old ** 。 · Patients who have received a fixed dose of acetylcholinesterase inhibitor in the 4 months prior to baseline. · Patients cared for by a reliable spouse or caregiver to ensure compliance, clinical evaluation, and reporting of safety issues. · Women must have been amenorrheic, using surgical contraception, or reliable contraceptive methods for at least 1 year. · Patients who, in the judgment of the investigator, can understand and provide an informed consent document. · Patients and caregivers must be fluent in the language of the trial and able to comply with all trial procedures. · Patients must be conscious, alert, able to make correct judgments 4 times, and provide an informed consent document (applicable only in some countries). * For the booster injection in cohort 3, the previous lower limit of 18 points for MMSE was not required, but in all cases, patients had to be able to correctly judge time, place, person recognition, and current activities and submit an informed consent, in the judgment of the investigator, to participate. ** For the booster injection in cohort 3, the upper age limit did not apply.

[0076] Exclusion criteria: · Patients with an MRI scan in the last 6 months showing severe cerebrovascular disease and / or another pathology including more than 5 microbleeds. · Patients with other medical conditions that can affect cognitive ability, such as Parkinson's disease. · Patients with any unstable medical condition (e.g., epilepsy, uncontrolled hypertension) that may interfere with safety assessment. · Patients who received memantine in the 3 months prior to baseline (for the booster injection in cohort 3, memantine is acceptable). · Patients who are receiving any anticoagulant. · Patients with a history of hemorrhagic stroke. · Patients with a history of non-hemorrhagic stroke or myocardial infarction in the last year. · Patients with a history of major mental disorder in the past two years. · Patients with a history of inflammatory neurological disorders including meningoencephalitis. · Clinically significant abnormalities in clinical hematology or biochemistry, including but not limited to increases more than 1.5 times the upper limit of normal for SGOT, SGPT, or creatinine. · Patients with a history of autoimmune diseases. · Patients with a history of cancer other than skin cancer in the past five years. · Patients who received any vaccine in the 2 months prior to baseline. · Patients who previously received an AD immunotherapeutic agent or vaccine. · Patients who are predicted to receive any vaccination other than the investigational influenza vaccine during the trial. · Patients who cannot undergo MRI examination for any reason, including metal implants and claustrophobia. · Patients with a positive HIV test at screening. · Patients with a positive syphilis serology. · Pregnant women or women planning pregnancy or breastfeeding.

[0077] Results / Conclusions: Forty-eight mild to moderate AD patients were randomized and exposed to ACI-24 at various dose levels (10 μg, 100 μg, 300 μg, and 1000 μg / dose) with up to 7 subcutaneous injections over 12 months. Some patients from the two highest dose cohorts received an additional single post-booster dose (i.e., a total of 8 subcutaneous injections). The anti-a beta IgG response was not observed in placebo-treated patients and patients treated at the two lowest doses tested (10 μg and 100 μg of antigen, cohorts 1 and 2). The vaccine was able to induce an anti-a beta antibody response in human subjects who required it, at the highest doses tested (300 μg and 1000 μg of antigen, cohorts 3 and 4), and a dose-dependent anti-Aβ IgG response was observed at the two highest doses. An administration-related delayed IgG response was observed. At all test doses, safety was considered good in the trial (10 μg to 1000 μg of antigen). No signals of SAE, CNS inflammation or other adverse responses to the vaccine related to the trial treatment, ARIA-E, ARIA-H (a low signal of 1 micro-lesion in a hemosequence where microbleeding was suspected, shown at the 100 μg ACI-24 dose (possibility of artifactual results)), signs of meningoencephalitis onset, and induction of T cell activation and inflammatory cytokines were observed. A dose-dependent trend of reduction in brain amyloid accumulation was observed at week 52 in both cohorts 3 and 4, at the two highest doses (Figure 1). The trial was not based on the clinical efficacy and PET scan parameters of a limited number of enrolled subjects (small trial population), but exploratory analysis confirmed a positive trend in cognition measured by MMSE. This was observed during the treatment period at the highest dose in cohort 4, relative to placebo and low doses (Figure 2). Similarly, exploratory analysis confirmed a positive trend in cognition / function measured by CDR-SB, observed during the treatment period at the highest dose, relative to placebo and low doses (Figure 3).

[0078] Example 2. Safety and Efficacy in Humans in a Phase II AD Trial Purpose of the clinical trial: The overall trial objective was to evaluate the safety, immunogenicity, and efficacy / target engagement of ACI-24 administered to patients with mild Alzheimer's disease (AD) diagnosed according to the National Institute on Aging - Alzheimer's Association (NIA-AA) criteria and having a score of 20 - 28 on the Mini-Mental State Examination (MMSE) at initial screening.

[0079] Primary purpose: ·Evaluate the safety and tolerability of ACI-24 in patients with mild Alzheimer's disease. ·Evaluate the effect of ACI-24 on inducing anti-Aβ antibody response in serum. ·Evaluate the effect of ACI-24 on brain amyloid burden in patients with mild Alzheimer's disease by florbetaben-PET imaging at week 52 (12 months) and week 76 (18 months).

[0080] Secondary purpose: ·Explore the effect of ACI-24 on putative biomarkers of Alzheimer's disease progression, including the concentrations of total tau, phosphorylated tau protein (phosphotau), and Aβ in blood and / or CSF. ·Explore the effect of ACI-24 on T cell activation in blood. ·Explore the effect of ACI-24 on whole brain and hippocampal volumes by volumetric MRI. ·Explore the effect of ACI-24 on clinical and cognitive endpoints in patients with mild Alzheimer's disease. ·Explore the effect of ACI-24 on blood inflammatory cytokines.

[0081] Inclusion criteria: At screening, patients who meet all of the following inclusion criteria should be considered eligible to participate in the clinical trial. 1. Probable AD dementia according to the NIA-AA core clinical criteria 2. Florbetaben-PET scan consistent with the presence of amyloid pathology at screening 3. Mini-Mental State Examination (MMSE) score of 20 - 28 4. 50 years of age or older and 85 years of age or younger 5. Patients who have received a stable dose of acetylcholinesterase inhibitor for at least 3 months prior to baseline 6. Patients who are being cared for by a reliable spouse or caregiver to ensure compliance, clinical evaluation, and reporting of safety issues, and the spouse or caregiver, have agreed to fulfill this role. 7. Women must have been amenorrheic, surgically sterilized, or using reliable contraception for at least one year. 8. Patients who, in the opinion of the investigator, can understand and provide an informed consent document. 9. Patients and caregivers must be fluent in the official language of the country in which they live and be able to comply with all trial procedures. 10. Patients must be conscious and alert and have correctly judged four times (recognition of person, place, time / date, and event) [applicable only in some countries].

[0082] In the first cohort, intramuscularly administered ACI-24 is tested. This trial is a multi-center, prospective, placebo-controlled, double-blind, and randomized trial evaluating treatment with ACI-24 formulation versus placebo over 76 weeks (18 months) in patients with mild Alzheimer's disease. The antigen dose is related to tetra-palmitoylated Aβ1-15 acetate. The vaccine formulation is an injectable suspension (liposome suspension in PBS).

[0083] Cohort 1 with ACI-24: A single dose of ACI-24 at 1000 μg / dose via the intramuscular route is tested. Patients are randomized in a 2:1 active (ACI-24) to placebo ratio. For patients participating in Cohort 1, the treatment period lasts 76 weeks, and the treatment / placebo is administered 8 times (the dose for each trial treatment is administered by two separate simultaneous intramuscular injections); 4 times at 4-week intervals, 3 times at 12-week intervals, and once 26 weeks after the 7th and previous dose. After the treatment period, there is a 24-week safety follow-up starting 2 weeks after the last dose. Patients who receive fewer than 8 doses for any reason are followed for at least a certain period after the last dose. Free, total, and immunocomplexed IgG titers are measured.

[0084] Example 3. Safety and Efficacy in Humans in a Phase Ib DS Trial Primary purpose: · To evaluate the safety and tolerability of ACI-24 in adults with Down syndrome. · To evaluate the effects of various doses of ACI-24 on anti-Aβ Ig titer induction in serum.

[0085] Secondary purpose: · To explore the efficacy of ACI-24 on the Clinical Global Impression of Change (CGIC) in adults with Down syndrome. · To explore the effects of ACI-24 on cognitive (CANTAB motor control, reaction time, paired associate learning; BPT) and behavioral (VABS, NPI) endpoints in adults with Down syndrome. · To explore the effects of ACI-24 on whole brain, ventricular, and hippocampal volumes by MRI. · To explore the effects of ACI-24 on peripheral T cell activation. · Plasma and / or, if applicable, CSF * ( * in subgroups) on putative biomarkers of Alzheimer's pathology in Down syndrome, including Aβ levels, total tau, phosphorylated tau protein (phospho-tau), sAPPα, sAPPβ, orexin A, inflammatory cytokines, angiogenic proteins, TLR-4 expression, and vascular injury markers. · CSF * ( * in subgroups) to evaluate the effects of various doses of ACI-24 on anti-Aβ Ig titer induction.

[0086] Method: This is a prospective, multi-site, placebo-controlled, double-blind, and randomized trial of two doses of ACI-24 treatment versus placebo over 24 months. The trial consists of two-dose cohorts of 8 subjects each (in each dose cohort, 6 subjects received ACI-24 300 μg, 6 subjects received ACI-24 1000 μg, and 2 subjects received placebo), and were injected s.c. at 0 months, 1 month, 2 months, 3 months, 6 months, 9 months, and 12 months (or more precisely, at week 0, week 4, week 8, week 12, week 24, week 36, and week 48), with a 12-month treatment-free safety follow-up. The dose cohorts were tested sequentially in ascending order of dose. The second dose cohort was initiated after the safety and tolerability data of the last subject in the previous cohort up to the 8th [14th week] visit were reviewed by the Data Safety Monitoring Board (DSMB). The antigen dose relates to tetra-palmitoylated Aβ1-15 acetate. The vaccine formulation is an injectable suspension (liposome suspension in PBS). Interim analysis in this trial was conducted based on the grounds that dose escalation would be possible after the 8th [14th week] visit of the last subject in cohort 1. The analysis was focused on safety and tolerability. The interim analysis was conducted in an unblinded manner, and the unblinded data were submitted to the DSMB. Further interim analyses are planned after the 9th [16th week], 12th [28th week], 15th [40th week], and 18th [52nd week] visits of the last subjects in cohort 1 and cohort 2, respectively. These analyses will be focused on safety, tolerability, antibody titers, and inflammatory cytokine data (part of the biomarkers). The interim analyses at the 12th [28th week] and 18th [52nd week] visits will further include biomarkers as well as CGIC, NPI, and Vineland data (part of the clinical rating scales and cognitive tests).

[0087] Inclusion criteria: · Males or females aged 25 to 45 years with Down syndrome cytogenetically diagnosed with trisomy 21 or a complete unbalanced translocation of chromosome 21. · The subject and the trial partner / legal representative can, in the judgment of the trial doctor, understand and provide an informed consent document. · An informed consent document was obtained from the subject and the trial partner / legal representative before any trial-related actions. · In the judgment of the investigator, the subject is proficient in English enough to participate fully in the trial and to enable reliable evaluation of the trial to be carried out. · The subject has a trial partner / legal representative who has direct contact with the subject for at least 10 hours per week and can answer questions about the subject.

[0088] Exclusion criteria: · Subjects weighing less than 40 kg. · IQ less than 40 (evaluated by the Kaufman Brief Intelligence Test, Second Edition (KBIT-2)). · In the judgment of the investigator, any clinically significant current mental or neurological disorder other than Down syndrome (including past disorders with a risk of recurrence). · Any medical condition that may significantly interfere with the safety evaluation of the investigational drug. · Currently meets the DSM-IV criteria for drug or alcohol abuse or dependence in the past 5 years. · Has a history of or has an unmanaged seizure. If there is a history of seizures, there must have been no seizures in the past 2 years before trial screening and it must be well managed. The use of anti-seizure medications is permitted. · History of meningitis or meningoencephalitis. · Has a history of malignant neoplasm in the past 3 years before trial screening or evidence of current disease recurrence or metastasis. · History of permanent cognitive deficit immediately after head trauma. · History of inflammatory neuropathy. · History of autoimmune diseases that may involve the CNS. · MRI scan at screening showing one area of evidence of cerebral edema, superficial siderosis, or previous large hemorrhage or more than 4 cerebral microbleeds (regardless of anatomical location or diagnostic characterization as "possible" or "definite"). · MRI examination is contraindicated due to metal implants or any reason including severe claustrophobia that prevents the MRI examination from being performed. ·Significant hearing or visual impairment or other problems appropriately determined by the investigator that comply with the protocol and prevent the conduct of outcome measurements. ·Severe infection or major surgery within 3 months prior to screening. ·History of chronic or recurrent infection clinically determined by the investigator to be significant. ·History or presence of immunological or inflammatory conditions clinically determined by the investigator to be significant. ·Celiac disease without a gluten-free diet for at least 3 months prior to study screening. ·Chronic benign skin conditions, unless determined by the investigator not to be clinically significant. ·Any vaccination within 2 months prior to baseline other than the influenza vaccine; if the influenza vaccine, it should be administered at least 2 weeks before baseline if necessary. ·Clinically significant arrhythmia or other abnormalities on ECG at screening (minor abnormalities recorded by the investigator as not being clinically significant are acceptable). ·Clinically significant abnormal vital signs, including sustained sitting blood pressure higher than 160 / 90 mmHg. ·Deviations from normal values of hematological parameters, liver function tests, and other biochemical measurements determined by the investigator at the study site to be clinically significant. ·Subjects with hypothyroidism during treatment not on stable medication for at least 3 months prior to screening, with clinically significant abnormalities in serum T-4 and TSH at screening. ·Subjects with diabetes having HbA1c ≥ 8.0%. ·Subjects who have received any investigational drug for Down syndrome and have less than either 30 days of washout or 5 half-lives of the drug, whichever is longer. ·Female subjects with pregnancy confirmed by serum test at screening or who are planning pregnancy or lactation. ·Female subjects not using a reliable method of contraception (except abstinence). · Patients who have received any anticoagulant or aspirin at a dose exceeding 100 mg per day within 7 days prior to lumbar puncture (to avoid the risk of bleeding during scheduled or unscheduled lumbar puncture). · Use of antidepressants other than stable doses of SSRI / SNRI, antipsychotics (typical or atypical), GABA agonists (e.g., gabapentin) or stimulants (e.g., methylphenidate, modafinil). Exceptionally, low-dose atypical antipsychotics (e.g., up to risperidone 0.5 mg / day or quetiapine 50 mg / day) or benzodiazepines are only permitted after review by the principal investigator of the project and / or the medical monitor and with the consent of the facility's representative investigator. · Use of current immunosuppressants or immunomodulators or their use within 6 months prior to the screening for the trial. Use of current oral steroids or their use within 3 months prior to the screening for the trial. · Use of cholinesterase inhibitors or glutamatergic drugs (topiramate, memantine, lamotrigine) if not at a stable dose for at least 3 months prior to screening. · Subjects who have donated blood or had apheresis within 30 days prior to screening and are planning to donate blood during the trial participation period or within 4 weeks after the trial completion.

[0089] Results The trial is a well - registered, placebo - controlled, Phase 1b trial of the ACI - 24 anti - A beta vaccine. 16 subjects were randomized in the trial. The vaccine was able to induce an anti - A beta antibody response in human subjects who required it at both doses tested (300 μg and 1000 μg of antigen). An early - onset IgG response was observed, with titers first increasing at week 4. According to MSD data, a boost effect was observed over time, and the anti - A beta antibody response was consistent in the majority of patients at the highest dose. The vaccine had good tolerability in DS subjects and showed a favorable safety profile at all test doses. Safety was considered good in the trial at the doses tested. There were no subjects who discontinued during the treatment period. No signals of SAE, CNS inflammation or other serious adverse responses to the vaccine, ARIA - E, ARIA - H, signs of encephalitis onset, as well as T - cell activation and induction of inflammatory cytokines related to the trial treatment were observed. The subsequent DS clinical development plan (Example 5) focuses on preventive treatment, especially using biomarker endpoints (such as A beta, neurofilament, and tau). Further, to boost immunogenicity, the vaccine is administered intramuscularly at the highest dose (1000 μg). Two of the selected read - out information are PET scan imaging and measurement of free, total, and immunocomplexed IgG titers generated by the vaccine.

[0090] Example 4. Toxicity Test: 4.1 Single - Dose Toxicity The single - dose toxicity of ACI - 24 was evaluated in two non - clinical models (mice and monkeys). ACI - 24 had good tolerability and was not associated with organ toxicity. The two tests are summarized below.

[0091] 4.1.1 Evaluation of Single - Dose Toxicity after Subcutaneous or Intramuscular Administration in Mice Purpose To evaluate the toxicity, local tolerability, and potential immunogenicity of a single s.c. or i.m. injection in mice.

[0092] Design The tests were conducted under GLP standards. The number of animals in each group, the dosage form administered, the route of administration, and the dosage levels are summarized in Table 1. An observation period of 14 days was established to evaluate the potential for delayed toxicity and / or the reversibility of the observed changes in the animals. Satellite groups were added for both routes of administration (s.c. and i.m.) to evaluate the immune response on day 14 and on day 1, 3, or 7 only for the s.c. route of administration.

[0093]

Table 3

[0094] The animals were checked for deaths at least once a day and for clinical signs at least twice a day (three times on day 1). The skin response at the injection site was recorded before injection and then at 6 hours, 24 hours, and 48 hours after injection, then at 3 days and 7 days. The rectal temperature was recorded before injection and then at 6 hours, 24 hours, and 48 hours after injection and at the end of the observation period. Body weight and food intake were recorded at least three times a week. Hematological and blood biochemical examinations were performed on three of the first major animals and three of the last major animals, respectively, at the end of the observation period. Aβ1-42 specific IgG and IgM antibodies were determined by ELISA. At the end of the observation period, all surviving animals were sacrificed and subjected to a complete macroscopic post-mortem examination. Spleens from all satellite animals were sampled for lymphocyte cell separation. The weights of the designated organs were measured and selected tissue sections were preserved for the primary animals. Microscopic tests were performed at the subcutaneous injection sites of two satellite mice in Group 6 (a total of 9 male and 9 female mice were sacrificed 1 day, 3 days, and 7 days after injection), and stained with hematoxylin and eosin (HE) or with polyclonal rabbit anti-Aβ1-40 precursor protein that would later become Aβ. Subsequent microscopic tests were performed at the intramuscular injection sites (formalin-fixed muscle samples) of mice in Group 8 (6 males and 6 females), and stained with hematoxylin-eosin.

[0095] Results A single administration of ACI-24 to mice via the s.c. (dose levels of 65 μg, 260 μg, or 385 μg / injection) or i.m. route (dose level of 65 μg / injection), followed by a 14-day observation period, had good tolerance. During the test period, no deaths were observed due to treatment with the vehicle or the test article formulation. There were no toxicologically relevant clinical signs and / or differences in rectal temperature due to treatment with the test article. No treatment-related skin responses were shown. There was no effect of treatment with the test article on body weight and food intake. In the examination of test values, no toxicologically relevant differences in hematological or biochemical parameters were observed in animals receiving empty liposomes or the test article. Microscopic tests at the i.m. injection sites showed that administration of ACI-24 (2 × 32.5 μg / injection) into the gastrocnemius muscle produced minimal to slight non-harmful granulomatous inflammation characterized by mononuclear cell infiltration associated with minimal fibrosis in all treated mice 2 weeks later. These findings were considered non-harmful because of the low severity.

[0096] Conclusion Under the experimental conditions of this study, a no-observed-adverse-effect level (NOAEL) was established at a dose of 65 μg / injection via the i.m. route and 385 μg / injection via the s.c. route.

[0097] 4.1.2 Evaluation of the toxicity of ACI-24 after single subcutaneous administration in monkeys Purpose The toxicity and local tolerance of single subcutaneous injection of ACI-24 in cynomolgus monkeys were evaluated in this GLP study.

[0098] Design The test design is described in Table 2. [Table 4] · Administered once on Day 1. · Local tolerance was evaluated at 6 hours, 24 hours, 48 hours, and 7 days later. · Rectal temperature was recorded at 6 hours, 24 hours, 48 hours, and 14 days later. · ACI-24-250 and ACI-24-1000 correspond to the target doses of 250 μg and 1000 μg of the αβ1-15 antigen, respectively.

[0099] The dosage form was administered once on Day 1. Clinical signs were evaluated at least three times a day during the test and further at approximately 6 hours after treatment on the treatment day. The local tolerance at the injection site was evaluated on the treatment day, before injection, and at 6 hours, 24 hours, 48 hours, and 7 days after treatment. Rectal temperature was recorded on the treatment day, before injection, at 6 hours, 24 hours, 48 hours, and at the end of the 14-day observation period after treatment. The body weight of each animal was recorded at specified intervals, and the food intake was estimated during the test. Electrocardiogram examination, blood pressure measurement, and laboratory tests (including hematology, blood biochemistry, urine test, blood lymphocyte fraction analysis, and quantification of the seric immune response) were performed during the pretreatment period, after treatment, and during the observation period. Ophthalmic tests were performed once during the pretreatment period and at the end of the 14-day observation period. At the end of the observation period, the animals were sacrificed, the organ weights were recorded, and gross postmortem examination and microscopic tests of selected tissues were performed.

[0100] Results A single administration of ACI-24 or empty liposomes by s.c. injection to cynomolgus monkeys was well tolerated. There were no unexpected deaths during the test. No systemic clinical signs were shown in any of the animals after treatment or during the observation period. There were no statistical differences in body temperature at any time point between the control animals and the treated animals. The recorded values were within the normal range recorded in healthy animals of this species and this age. It was considered that body weight and food intake were not affected by the test article treatment. Electrocardiogram parameters, including PQ and QT intervals, QRS complex duration, and heart rate, were not affected by the test article treatment. Systolic and diastolic blood pressure measurements were not affected by the test article treatment at all time points. No relevant ophthalmological findings were observed in any of the groups during the pretreatment period or at the end of the treatment period. Hematological parameters, including lymphocyte fraction populations, blood biochemistry, and urine tests, were not affected by the test article treatment at all time points. At autopsy, organ weights were not affected by the test article treatment, and no macroscopic lesions related to systemic treatment were observed.

[0101] Conclusion The NOAEL after a single systemic administration of ACI-24 was considered to be 385 μg of peptide / injection under the experimental conditions of this study.

[0102] 4.2 Repeated-dose toxicity Study to evaluate the potential cross-reactivity of cynomolgus monkey antibodies to ACI-24 with a panel of selected normal human tissues Objective The objective of this GLP study was to evaluate the potential cross-reactivity of serum antibodies from cynomolgus monkeys treated with ACI-24 against histological frozen sections of human tissues using immunohistochemical techniques.

[0103] Design ​The test article was a serum preparation from cynomolgus monkeys pre-immunized with ACI-24 (animal 6529, day 31), injected with the vaccine ACI-24-250-other vaccine batches (Pal 1-15 antigen: 80 μg / dose target, MPLA: 30 μg / dose target) on day 2 and day 24 (blood collected on day 31, used for immunostaining). This serum contained anti-amyloid (Aβ) IgG antibodies at a concentration of approximately 4 μg / mL. Serum from empty liposome-immunized monkeys was used as the negative control serum (animal 6613, day 49). The test system used frozen sections (5 μm thick) of human Alzheimer's brain tissue (cortex) identified as positive for the antibodies generated in animal 6529, day 31 (serum from ACI-24 immunized monkeys). Human healthy brain tissue (same region) was used as the negative control. The system was verified by the selection of tissues with numerous small, distinct amyloid plaques that were Aβ positive by screening with mouse anti-Aβ antibody. The detection method was verified using serial dilutions of the test serum and the negative control serum to determine the optimal dilution that produced specific positive immunohistochemical staining with minimal non-specific background staining in human Alzheimer's and healthy brain tissues. Frozen sections from a panel of selected human tissues (Table 3) were used to evaluate the potential for tissue cross-reactivity.

[0104]

Table 5

[0105] Results Tissue viability was confirmed using anti-human antibodies against vimentin, von Willebrand factor (endothelial marker), cytokeratin, and transferrin receptor (CD71). Furthermore, frozen sections from whole tissues stained with hematoxylin and eosin showed no significant autolysis. The titer measurement results showed that the 1:2000 dilution of serum 6529, on the 31st day (serum of ACI-24 immunized monkeys), was optimal because specific staining of amyloid plaques was observed and the non-specific background staining of surrounding tissues in human Alzheimer's brain tissue was minimal. No corresponding positive staining was seen in human brain-cortex negative control tissue. For human tissue titer measurement, dilutions of 1:2000 and one lower (1:1000) and one higher (1:4000) were used. No specific positive staining was seen for any of the human tissues tested against serum 6529, on the 31st day (serum of ACI-24 immunized monkeys). Throughout most of the tissue, this serum non-specifically stained smooth muscle cells (blood vessels, mucosal muscularis and muscular layer), myoepithelial cells and other occasional stromal cells. Various non-specific stainings were seen in most of the test tissues, which was thought to be due to the use of goat anti-monkey IgG antibody that interacts with both cynomolgus monkey serum 6529, on the 31st day (serum of ACI-24 immunized monkeys) and negative control serum (serum of empty liposome immunized monkeys). Although the intensity was higher with serum 6529, on the 31st day (serum of ACI-24 immunized monkeys) than the negative control (serum of empty liposome immunized monkeys), the location and distribution of the staining of serum 6613, on the 49th day (serum of empty liposome immunized monkeys) should be considered non-specific. The minimal amount of non-specific staining was also seen in the buffer replacement negative control and was thought to be due to inappropriate quenching of endogenous peroxidase in smooth muscle, connective tissue and macrophages. This minimal non-specific staining considered to be endogenous peroxidase was added to that seen as a result of incubation with serum 6529, on the 31st day (serum of ACI-24 immunized monkeys) and negative control serum (serum of empty liposome immunized monkeys).

[0106] Conclusion The results showed that there was no specific positive staining due to the anti-ACI-24 antibody in serum 6529, on the 31st day. It can be concluded that cynomolgus monkey antibodies against ACI-24 do not cross-react with human tissues.

[0107] 4.2.2 Repeated dose toxicity after subcutaneous administration of ACI-24 in cynomolgus monkeys Purpose The purpose of this study was to evaluate the potential toxicity of the test article, ACI-24, when administered subcutaneously to cynomolgus monkeys every 4 weeks for 21 weeks. After completion of the treatment period, the designated animals were maintained for a 2-week drug-free period to evaluate the reversibility of any observed toxicity. Another purpose of this study was to analyze the induction of T cell responses by ACI-24 in monkeys.

[0108] Design Two groups of 3 male and 3 female cynomolgus monkeys were treated with the test article, ACI-24, at peptide / injection dose levels of 28 μg (Group 3) or 78 μg (Group 4) by the s.c. route every 4 weeks for a total of 6 injections (21 weeks). Five male and 5 female cynomolgus monkeys were treated according to the same treatment design at a peptide / injection dose level of 311 μg (Group 5). Three male and 3 female (Group 2) were treated with ACI-24-vehicle and five male and 5 female (Group 1) were treated with PBS, both serving as control groups. Two animals / sex from Groups 1 and 5 were maintained for a 2-week recovery period.

[0109]

Table 6

[0110] Blood samples for immunotoxicology studies were collected during the pretreatment period, at week 15, week 19 and at the end of the treatment period. Blood samples for immunoresponse analysis were collected from all animals during the treatment period and from the remaining animals in Groups 1 and 5 weekly during the observation period (except week 1). Animals were checked twice daily for death and clinical signs. Body weight was recorded twice during the pretreatment period, on the first day of treatment, and then weekly until the end of the study. Rectal temperature was taken before treatment (treatment day) and 6 hours, 24 hours, and 48 hours after treatment. Additionally, it was measured at the end of the 2-week observation period in the remaining animals of groups 1 and 5. Rectal temperature was recorded on day 15 in all animals. Food intake was estimated daily throughout the study. Ophthalmic examinations were performed once in all animals before the study and at the end of the treatment period. Electrocardiogram examinations and blood pressure measurements were performed once in all animals before the study, then at least 2 hours after the last administration and at the end of the treatment period. Blood tests were performed in all animals before the study, then at week 9, 15, 19, 21, 22, and at the end of the recovery period. Blood biochemical tests were performed in all animals before the study, then at week 9, 22 (the end of the treatment period), and at the end of the observation period. Urine tests were performed before the study and at the end of the treatment period. These tests were also performed in the remaining animals of groups 1 and 5 at the end of the observation period. Animals were subjected to a complete macroscopic postmortem examination. Additionally, the weights of specified organs were measured and selected tissue sections were preserved. Microscopic examinations were performed on specified tissues from all animals sacrificed at the end of the treatment period. To investigate the T cell response, peripheral blood mononuclear cells (PBMCs) from monkeys treated with PBS, ACI-24-empty, ACI-24-30, ACI-24-125, or ACI-24-500 were harvested between days 113 and 148 after the first immunization corresponding to the time point when an antibody response was observed. PBMCs were restimulated with concanavalin A (positive control), Aβ1-42, Aβ1-15, or cell culture medium (negative control). Cells were incubated with the stimulant for 3 hours and then transferred to ELISPOT plates and incubated for 48 hours. Detection of IFN-γ, IL-4, and IL-5-producing cells was performed using an alkaline phosphatase-based detection system with an ELISPOT reader.

[0111] Results No unexpected deaths or early euthanasia occurred during the test. Hypertrophy, edema, and nodules were observed at the injection site in a severity corresponding to the dose, and persisted for 1 - 2 days and 1 - 2 weeks after administration of the dosage form. Nodules were observed in some animals for 1 month, and there was no correlation with the administered dose levels. No local responses were observed in PBS - treated control animals or ACI - 24 - empty - treated animals. Animals treated with the test article at the active level showed slight to moderate local responses at the injection site. During the treatment and observation period, body weight and weight gain were considered similar in control and treated animals. It was considered that food intake was not affected by treatment with the test article. No eye changes or electrocardiogram findings were shown during the test in control and treated animals. Hematological and blood biochemical parameters and urine tests were considered unchanged at the different time points evaluated. The s.c. - injected ACI - 24 vaccine induced a strong Aβ - specific IgG response in 5 monkeys. The responding monkeys were treated with ACI - 24 - 30 (1 monkey), ACI - 24 - 125 (1 monkey), or ACI - 24 - 500 (3 monkeys). Persistent anti - Aβ IgG potency was observed in 3 monkeys after day 120, suggesting that 5 immunizations were required to induce an anti - Aβ IgG response in monkeys. Monkeys treated with PBS or empty liposomes showed no detectable anti - Aβ IgG antibodies as expected. Similar results were observed when measuring the Aβ - specific IgG response in plasma instead of serum. ACI - 24 induced an anti - Aβ IgM titer in 1 out of 3 monkeys that received the highest dose (ACI - 24 - 500). ACI - 24 induced an anti - MPLA IgG titer in 2 monkeys after ACI - 24 - 30. Complete reversibility was shown at the end of the observation period. At the injection site, nodules and hypertrophy of the subcutaneous tissue correlated with s.c. granulomatous inflammation in all treatment groups, including the vehicle control group (empty liposomes). The lesions in the vehicle control group were all of minimal severity. The minimal lesions in animals receiving the active test article were essentially similar.

[0112] Conclusion Under the experimental conditions of this study, the NOAEL was determined to be 311 μg peptide / injection after 6 injections in cynomolgus monkeys. The local responses observed at the injection site did not affect the clinical status of the animals and were considered to be consistent with the normal granulomatous inflammatory response after s.c. injection of foreign substances. This study also shows that ACI-24 can overcome immune tolerance to Aβ1-15 in monkeys. The lack of correlation between IL-4 results and IFN-γ secretion by PBMCs from monkeys immunized with ACI-24 and restimulated with Aβ1-15, together with the very low T cell response, indicates a positive safety profile for ACI-24 due to the preferential Th2 response of the ACI-24 vaccine.

[0113] 4.2.3 13-Week Toxicity Study via Subcutaneous Route in hAPP V717I Transgenic Mice Purpose The purpose of this GLP-compliant study was to evaluate the potential toxicity of ACI-24 in transgenic mice overexpressing human amyloid precursor protein (hAPP V717I). The transgenic mouse model hAPP V717I reflects the pathophysiology of patients with Aβ plaque deposits in the brain and was therefore selected as the most appropriate model for the safety evaluation of ACI-24 based on the biological findings.

[0114] Design hAPP V717I mice were immunized with subcutaneous administration of ACI-24 every 2 weeks for a total treatment period of 13 weeks. hAPP V717I mice were divided into 5 different groups containing 3 different doses of peptide per injection (80 μg, 160 μg, and 400 μg; n = 28). PBS and empty liposomes (without peptide antigen) served as negative controls (n = 24). The study also tested the toxicity of MPLA incorporated into liposomes at a dose of 100 μg MPLA per injection.

[0115] The study design is summarized in Table 5.

Table 7

[0116] Results ACI-24 immunization induced a dose-dependent humoral anti-Aβ immune response characterized mainly by anti-Aβ IgG and low anti-Aβ IgM, · Treatment-related death · Increased mortality · Marked changes in clinical signs · Changes in body weight or relative or absolute organ weights · Dose-dependent changes in hematology and blood biochemistry were not brought about. Some non-dose-dependent changes were considered to have limited toxicological significance. ACI-24 treatment resulted in minimal to moderate subcutaneous tissue fibrosis at the injection sites in all treatment groups, and the incidence and severity were increased minimally in the liposome treatment groups (ACI-24 or empty liposomes) when compared to the PBS control group.

[0117] T cell response: Spleen cells isolated from mice immunized with high-dose ACI-24 (400 μg) and restimulated with Aβ1-15 peptide in vitro showed a significant increase in the number of IL-4-secreting cells, suggesting that ACI-24 preferentially induces a Th2 response. T cell proliferation was not observed.

[0118] Local brain inflammation: · Immunization with ACI-24 did not induce the release of pro-inflammatory cytokines (IFN-γ, TNF-α, IL-6) in the brains of immunized mice and was associated with a slight decrease in the levels of IFN-γ, TNF-α, and IL-6. · Immunization with high-dose ACI-24 (400 μg) did not increase any of T cells (CD3, CD4, and CD8), macrophages (F4 / 80), and B cells (B220 or CD45R) in the brains of immunized mice as evaluated by immunohistochemistry. · Immunization with ACI-24 did not increase the incidence of microbleeds (hemosiderin of Perl) in the brain or the severity of perivascular brown pigment-laden macrophages at any dose level when compared to the PBS control group. · Immunization with ACI-24 does not change the vascular density (collagen type IV), does not enhance thioflavin-S-positive amyloid plaques in blood vessels, and indicates only low-risk cerebral amyloid angiopathy (CAA).

[0119] Conclusion These data indicate that immunization with ACI-24 does not induce any of microbleeds, local brain inflammation, infiltration of peripheral inflammatory cells (T cells, B cells or macrophages), and perivascular accumulation of Aβ, providing the potential for the promising safety of ACI-24 as a vaccine. As supported by this test result, the NOAEL (no-observed-adverse-effect level) was set at 400 μg / injection of ACI-24 for systemic toxicity.

[0120] 4.2.4 Subcutaneous immunogenicity and toxicity test in cynomolgus monkeys Objective The objective of this GLP test was to evaluate the toxicity and immunogenicity of various batches of ACI-24 when subcutaneously administered to cynomolgus monkeys 5 times at 2-week intervals.

[0121] Design The test design is described in Table 6.

Table 8

[0122] Throughout the test, all animals were observed at least twice a day for viability / mortality and clinical signs. The injection sites were observed daily during the treatment and recovery periods. Food intake was estimated (qualitatively) twice a day per cage during the test. All animals had their body weights measured twice a week during the pre-test and then weekly during the treatment and recovery periods. Blood samples were taken for clinical chemistry investigations between the pre-test and the end of the treatment period (week 12). Blood samples were taken once during the pre-test and 14 days after each administration for IgG anti-A beta determination. At the end, blood samples were collected to obtain serum, plasma, and PBMCs, which were either stored or analyzed as part of another test. After completion of the scheduled treatment period, the animals from Groups 1, 3, and 4 were sacrificed and the weights of various organs were measured. Macroscopic changes were recorded. A set of tissues and organs was collected, processed, and histologically tested. The animals from Groups 2 and 5 were maintained for future investigations and were subsequently removed from the study.

[0123] Results There were no deaths during the implementation of the test protocol. There were no associated clinical signs or local effects at the injection sites. Food intake and body weight were not affected during the treatment period. Subcutaneous administration of three formulations of ACI-24 induced an equivalent profile of anti-Aβ IgG antibodies across all groups, thus showing appropriate correlation between batches. One animal vaccinated with ACI-24 “New Batch 6.9” (Group 3 female 24) showed a persistent anti-Aβ IgG titer three-fold higher than that generally seen from Day 43 onwards. Monkeys administered PBS showed no detectable anti-Aβ IgG antibodies as expected. There were no changes related to hematological or blood chemistry parameters. There were no relevant macroscopic findings or remarkable changes in the recorded organ weights at autopsy. Histological findings at the injection site consisted of single / multiple foci of mononuclear cells in the subcutaneous tissue, with an increased incidence in Group 3 and increased severity in Group 4. These findings were present in monkeys of all groups tested (1, 3 and 4), including one control male. These changes were of minimal to slight intensity and the distribution was strictly local.

[0124] Conclusion Five subcutaneous administrations of various batches of ACI-24 to cynomolgus monkeys every two weeks (up to about 1320 μg / injection) were well tolerated and did not affect body weight, food intake or clinical pathology parameters. Based on the results obtained under these test conditions, all batches of ACI-24 evaluated were considered equivalent in terms of toxicity and immunogenicity, and a dose of about 1320 μg / injection is currently considered the NOAEL (No Observed Adverse Effect Level).

[0125] Example 5: Phase 2 double-blind, randomized, placebo-controlled trial to evaluate the safety, tolerability and target engagement of ACI-24 in adults with Down syndrome Measurement of primary evaluation items: · Number of participants with adverse events (AE) evaluated by intensity (mild, moderate or severe) and causality (not related, probably not related, possibly related or probably related) [Period: From screening to Week 100] · Mean change from baseline in vital signs Systolic and diastolic blood pressure (mmHg), heart rate (bpm), body temperature (degrees Celsius) [Period: From baseline to week 100] · Mean change from baseline in suicidal thoughts / behavior using the Columbia-Suicide Severity Rating Scale (C-SSRS) [Period: From baseline to week 100] · Number of participants reporting suicidal thoughts or behavior using the Columbia-Suicide Severity Rating Scale (C-SSRS) [Period: From baseline to week 100] · Number of participants with abnormal MRI results Incidence of amyloid-related imaging abnormalities (ARIA) [Period: From baseline to week 100]

[0126] Measurement of secondary evaluation items: · Change from baseline in the ratio of standardized uptake values (SUVR) of composite evaluated by amyloid PET imaging using florbetaben [Period: From baseline to week 76] · Change from baseline in blood anti-Aβ antibody titer [Period: From baseline to week 100] · Change from baseline in amyloid-related biomarkers (Aβ1-40, Aβ1-42), total tau, phosphorylated tau and NfL in blood / CSF (pg / mL) (CSF is optional). [Period: From baseline to week 100] · Change from baseline in brain tau burden evaluated by tau PET imaging [Period: From screening to week 74] · Change from baseline in cognitive ability using the Cambridge Neuropsychological Test Automated Battery - Paired Associates Learning [CANTAB-PAL] Scores are z-scores in the range of -7.5 to 0. The higher the score (e.g., 0), the better the outcome is indicated. [Period: From baseline to week 100] · Changes from baseline in cognitive ability using the Cambridge Cognitive Examination - Down's Syndrome [CAMCOG-DS] [Period: From baseline to week 100] The total score ranges from 0 to 107. The higher the score, the better the outcome. · Changes from baseline in adaptive behavior (Vineland Adaptive Behavior Scales) [Period: From baseline to week 100] The composite score ranges from 20 to 140. The higher the score, the better the outcome. · Changes from baseline in Clinical Global Impression of Change (CGIC) [Period: From baseline to week 100] The score ranges from 1 to 7. The higher the score, the worse the outcome.

[0127] Method: This trial is a prospective, multi-center, placebo-controlled, double-blind, randomized trial evaluating the effect of a single dose of ACI-24 vaccine against placebo over a 74-week treatment period and a 26-week safety follow-up period. After the screening period, eligible subjects are randomized 1:1 to ACI-24 or the corresponding placebo, both administered via the intramuscular route. Approximately 72 subjects (36 subjects receiving 1000 μg of ACI-24 and 36 subjects receiving placebo) are randomized in this trial. Subjects are treated by repeated administration of ACI-24 (1000 μg dose) or the corresponding placebo using the intramuscular route. ACI-24 (1000 μg dose) or placebo is administered 8 times (each 1 dose of the test treatment is administered by 2 separate intramuscular injections): the first 4 administrations are at 4-week intervals (W0, W4, W8, and W12); the next 3 administrations are at 12-week intervals (W24, W36, and W48); and the last administration is at W74 (26-week interval from the previous administration). After the 74-week treatment period, there is a 26-week safety follow-up period.

[0128] Inclusion criteria: · Male or female subjects with DS cytogenetically diagnosed with trisomy 21 or a complete unbalanced translocation of chromosome 21. · 40 years of age or older and 50 years of age or younger at the time of screening. · Elevated cerebral Aβ demonstrated by a composite SUVR ≥ 1.25 on florbetaben PET scan as evaluated by central reading. · The subject, legal representative (if applicable), and / or study partner can understand and provide an informed consent document before the start of any study-related activities, as determined by the investigator. · The subject, legal representative (if applicable), and / or study partner can participate adequately in the study, are fluent in the official language of the country in which they live, and can complete the study assessment, as determined by the investigator. · Mild to moderate intellectual disability according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) classification. · The subject has a study partner who has direct and regular contact with the subject and can provide reliable answers to questions about the subject, as determined by the investigator. · Subjects in the preclinical stage of AD or with mild cognitive impairment due to AD.

[0129] List of references Belichenko PV, Madani R, Rey-Bellet L, et al. An Anti-β-Amyloid Vaccine for Treating Cognitive Deficits in a Mouse Model of Down Syndrome. PLOS ONE. 2016;11(3):e0152471. Folstein MF, Folstein SE, McHugh PR (1975) "Mini-Mental State": a practical method for grading the cognitive state of patients for the clinician J Psychiatr Res 12: 189 - 198 Gilman S., Koller M., Black R.S., Jenkins L., Griffith S.G., Fox N.C., Eisner L., Kirby L., Boada Rovira M., Forette F., Orgogozo J.M., Clinical effect of Aβ immunization (AN1792) in patients with AD in an interrupted trial. Neurology 64, 1553-1562 (2005). Hartley SL, Handen BL, Devenny D, et al. Cognitive decline and brain amyloid-β accumulation across 3 years in adults with Down syndrome. Neurobiology of aging. 2017;58:68-76. Head E, Powell D, Gold BT, Schmitt FA. Alzheimer's Disease in Down Syndrome. European journal of neurodegenerative disease. 2012;1(3):353-364. Hughes CP, Berg L, Danzinger WL et al (1982) A new clinical scale for the staging of dementia. Am J Psychiatry; 140: 566 - 572 Monsonego A., Weiner H.L., Immunotherapeutic approaches to Alzheimer's disease. Science. 31;302(5646):834-8 (2003). Muhs A., Hickman D.T., Pihlgren M., Chuard N., Giriens V., Meerschman C., van der Auwera I., van Leuven F., Sugawara M., Weingertner M.-C., Bechinger B., Greferath R., Kolonko N., Nagel-Steger L., Riesner D., Brady R.O., Pfeifer A., Nicolau C., Liposomal vaccines with conformation-specific amyloid peptide antigens define immune response and efficacy in APP transgenic mice. PNAS, 104 23:9810-9815 (2007). Nasreddine ZS, Phillips NA, et al. The Montreal Cognitive Assessment, MoCA: A brief screening tool for mild cognitive impairment. J Am Geriatr Soc. 2005;53:695-699. Orgogozo J.M., Gilman S., Dartigues J.F., Laurent B., Puel M., Kirby L.C., Jouanny P., Dubois B., Eisner L., Flitman S., Michel B.F., Boada M., Frank A., Hock C., Subacute meningoencephalitis in a subset of patients with AD after Abet42 immunization. Neurology 61: 46-54 (2003). Prasher VP, Huxley A, Haque MS (2002) A 24-week, doubleblind, placebo-controlled trial of donepezil in patients with Down syndrome and Alzheimer’s disease-pilot study. Int J Geriatr Psychiatry 17(3):270-278 (PMID: 11921156) Pihlgren M., Silva A.B., Madani R., Giriens V., Waeckerle-Men Y., Fettelschoss A., Hickman D.T., Lopez-Deber M.P., Ndao D.M., Vukicevic M., Buccarello A.L., Gafner V., Chuard N., Reis P., Piorkowska K., Pfeifer A., Kuendig T.M., Muhs A., Johansen P., TLR4- and TRIF-dependent stimulation of B lymphocytes by peptide liposomes enables T cell-independent isotype switch in mice. Blood. Jan 3;121(1):85-94 (2013). Soto C., Plaque busters: strategies to inhibit amyloid formation in Alzheimer’s disease. Molecular Medicine Today (vol 5), August 1999. Winblad B., Graf A., Riviere M.E., Andreasen N., Ryan J.M., Active immunotherapy options for Alzheimer's disease. Alzheimers Res Ther. 2014 Jan 30;6(1):7.

[0130] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. All publications and patents specifically mentioned herein are hereby incorporated by reference in their entirety for all purposes related to this invention.

[0131] The invention is not limited in scope by the specific embodiments described herein. Indeed, in addition to what is described herein, various modifications of the invention will become apparent to those skilled in the art from the foregoing and the appended drawings. Such modifications are intended to fall within the scope of the appended claims. Further, all aspects and embodiments of the invention described herein are broadly applicable and are to be construed as being capable of being combined, as appropriate, with any and all other compatible embodiments, including those from other aspects of the invention (including isolated ones).

Claims

1. a. A β-amyloid (Aβ)-derived peptide antigen presented on the surface of a liposome, which is tetra-palmitoylated A beta 1-15 of SEQ ID NO: 1; and b. An adjuvant containing monophosphoryl lipid A (MPLA) A liposome vaccine composition comprising the above, wherein the β-amyloid (Aβ)-derived peptide antigen is administered in an amount of 300 to 2000 μg as tetra-palmitoylated A beta 1-15 (SEQ ID NO: 1), A liposome vaccine composition for inducing an anti-Aβ immune response without inducing severe adverse events in a human subject.

2. The liposome vaccine composition according to claim 1, wherein the β-amyloid (Aβ)-derived peptide antigen is administered in an amount of 500 to 2000 μg, 1000 to 1500 μg, or 1000 μg as tetra-palmitoylated A beta 1-15 (SEQ ID NO: 1).

3. The liposome vaccine composition according to claim 1 or 2, wherein MPLA is administered in an amount of 15 to 600 μg, 50 to 600 μg, 150 to 450 μg, 175 μg or 225 μg.

4. The liposome vaccine composition according to any one of claims 1 to 3, wherein the β-amyloid (Aβ)-derived peptide antigen is administered in an amount of 850 to 1150 μg as tetra-palmitoylated A beta 1-15 (SEQ ID NO: 1) and the MPLA adjuvant is administered in an amount of 50 to 300 μg.

5. The liposome vaccine composition according to claim 4, wherein the β-amyloid (Aβ)-derived peptide antigen is administered in an amount of 1000 μg as tetra-palmitoylated A beta 1-15 (SEQ ID NO: 1), or the β-amyloid (Aβ)-derived peptide antigen is administered in an amount of 1000 μg as tetra-palmitoylated A beta 1-15 (SEQ ID NO: 1) and the MPLA adjuvant is administered in an amount of 175 or 225 μg.

6. The liposome vaccine composition according to any one of claims 1 to 3, wherein the β-amyloid (Aβ)-derived peptide antigen is administered in an amount of 300 μg as tetra-palmitoylated A beta 1-15 (SEQ ID NO: 1), or the β-amyloid (Aβ)-derived peptide antigen is administered in an amount of 300 μg as tetra-palmitoylated A beta 1-15 (SEQ ID NO: 1) and the MPLA adjuvant is administered in an amount of 52.5 or 67.5 μg.

7. The liposome vaccine composition according to any one of claims 1 to 6, wherein the adjuvant forms the outer layer of the liposome and / or the adjuvant is at least partially presented on the surface of the liposome.

8. The liposome vaccine composition according to any one of claims 1 to 7, wherein the monophosphoryl lipid A (MPLA) comprises synthetic monophosphoryl lipid A (MPLA).

9. The liposome vaccine composition according to claim 8, wherein the monophosphoryl lipid A (MPLA) comprises monophosphoryl hexa-acyl lipid A, 3-deacyl (synthetic) (3D-(6-acyl)PHAD (registered trademark)) and / or phosphorylated hexa-acyl disaccharide (PHAD (registered trademark)).

10. The liposome vaccine composition according to any one of claims 1 to 9, wherein the liposome comprises a phospholipid.

11. The liposome vaccine composition according to claim 10, wherein the phospholipid comprises dimyristoyl phosphatidylcholine (DMPC) and dimyristoyl phosphatidylglycerol (DMPG).

12. The liposome vaccine composition according to any one of claims 1 to 11, wherein the liposome comprises cholesterol.

13. The liposome vaccine composition according to claim 11, wherein the liposome comprises cholesterol, and the molar ratio of dimyristoyl phosphatidylcholine (DMPC):dimyristoyl phosphatidylglycerol (DMPG):cholesterol is 9:1:7, or the molar ratio of dimyristoyl phosphatidylcholine (DMPC):dimyristoyl phosphatidylglycerol (DMPG):cholesterol:MPLA is 9:1:7:0.

05.

14. The liposome vaccine composition according to any one of claims 1 to 13, wherein the liposome vaccine composition is for injection, intramuscular administration or subcutaneous administration.

15. The liposome vaccine composition according to any one of claims 1 to 14, wherein the liposome vaccine composition is administered according to a schedule in which a second administration is carried out 1 to 4 weeks after the first administration.

16. The liposome vaccine composition according to any one of claims 1 to 15, wherein as an initial administration schedule, it is administered at least every 4 to 12 weeks for 48 weeks.

17. The liposome vaccine composition according to claim 16, wherein as an initial administration schedule, it is administered every 4 weeks for 12 weeks and further administered every 12 weeks for at least 36 weeks.

18. The liposomal vaccine composition according to claim 16 or 17, which is further administered as a booster after the initial administration schedule is completed.

19. The liposomal vaccine composition according to any one of claims 1 to 18 for treating, preventing, inducing a protective immune response or alleviating symptoms associated therewith in a human subject for an amyloid-beta related disease or condition.

20. The liposomal vaccine composition according to claim 19, wherein the amyloid-beta related disease or condition is selected from Alzheimer's disease, mild cognitive impairment (MCI), Down syndrome (DS) including Down syndrome-related Alzheimer's disease, cardiac amyloidosis, cerebral amyloid angiopathy (CAA), multiple sclerosis, Parkinson's disease, Lewy body dementia, ALS (amyotrophic lateral sclerosis), adult-onset diabetes, inclusion body myositis (IBM), ocular amyloidosis, glaucoma, macular degeneration, lattice dystrophy and optic neuritis.

21. The liposomal vaccine composition according to claim 20, wherein the amyloid-beta related disease or condition is Alzheimer's disease.

22. The liposomal vaccine composition according to claim 21, wherein the Alzheimer's disease is early Alzheimer's disease, mild Alzheimer's disease, mild to moderate Alzheimer's disease, moderate Alzheimer's disease, or not severe Alzheimer's disease.

23. The liposomal vaccine composition according to claim 22, wherein the early Alzheimer's disease includes mild cognitive impairment due to Alzheimer's disease and mild Alzheimer's disease.

24. The liposomal vaccine composition according to claim 20, wherein the amyloid-beta related disease or condition is Down syndrome or Down syndrome-related Alzheimer's disease.

25. The liposomal vaccine composition according to any one of claims 1 to 24, wherein the human subject before treatment exhibits cognitive function corresponding to at least an 18 Mini-Mental State Examination (MMSE) score.

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