Anti-Aβ vaccine therapy

Abstract

A liposomal vaccine composition containing a β-amyloid (Aβ)-derived peptide antigen (comprising amino acids 1-15 of Aβ, consisting essentially of Aβ, or consisting of Aβ) presented on the surface of liposomes, a peptide containing a universal T cell epitope, and an adjuvant containing monophosphorylated lipid A (MPLA) is used to induce anti-Aβ immune responses in human subjects without inducing serious adverse events. The β-amyloid (Aβ)-derived peptide antigen (SEQ ID NO: 1) is administered in an amount of 300-2000 μg. The liposomal vaccine composition is administered intramuscularly or subcutaneously.

Description

[Technical Field]

[0001] FIELD OF THE INVENTION The present invention relates to anti-Aβ therapeutic vaccines and their use for inducing anti-Aβ immune responses without inducing serious adverse events. Such vaccines are useful for treating and preventing diseases, particularly amyloid-β-related diseases or conditions, or conditions characterized by or associated with the loss of cognitive memory, such as Alzheimer's disease (AD) and Down's syndrome (DS) (including Down's syndrome-associated Alzheimer's disease). These vaccines contain Aβ-derived peptide B cell antigens and T cell epitopes. [Background technology]

[0002] background Alzheimer's disease (AD) is a devastating, progressive degenerative disorder characterized by the loss of cognitive function, including memory, as well as the ability to perform daily activities. Approximately 40 million people worldwide are affected by AD, a number that is rapidly increasing with the aging population. The primary neuropathological change in the brains of AD patients is neuronal death, primarily in areas related to memory and cognition (Soto, 1999). One of the most striking pathological features of AD is the presence of abundant amyloid-β (Aβ, Abeta, β-amyloid, Aβ) plaques in the brains of patients (Soto, 1999). Aβ plaques are formed by Aβ peptides consisting of 39–43 amino acids, which naturally have a random coil structure in their nonpathological state. During the pathological process, Aβ primarily converts to a β-sheet secondary structure and spontaneously aggregates to form insoluble deposits.

[0003] While the majority of existing treatments for AD are thought to be primarily symptomatic, the most effective approach to date is passive immunization, in which anti-Aβ monoclonal antibodies are administered directly to patients. This approach led to the FDA's approval of Aduhelm® (aducanumab) in 2021, marking the first approved anti-Aβ monoclonal antibody therapy. More recently, the FDA approved another anti-Aβ monoclonal antibody, LEQEMBI® (lecanemab), under accelerated approval in January 2023, and LEQEMBI® (lecanemab-irmb) for the treatment of Alzheimer's disease in July 2023. Several other anti-Aβ monoclonal antibodies are currently in the final stages of development (e.g., Eli Lilly filed for full FDA approval of donanemab in July 2023). The advantage of vaccines is that they stimulate the immune system to generate a pool of slightly different but highly specific antibodies, which can be further stimulated by booster vaccinations if necessary. However, active immunization (vaccination) approaches against Aβ pose several major challenges. Amyloid-β is a so-called autoantigen, and the human body is constantly exposed to it. Therefore, breaking immune tolerance and inducing an antibody response is extremely difficult. Furthermore, elderly and frail patients, such as those with AD, have weakened immune systems and reduced immune cell counts, making it extremely difficult to induce a strong immune response to a vaccine.

[0004] Despite these challenges, early studies have reported that a full-length Aβ vaccine (AN1792) induced antibody responses and promising efficacy, with vaccinated patients experiencing a slower rate of cognitive decline than those given a placebo (Gilman, 2005). However, 6% of treated patients developed meningoencephalitis, an inflammatory response thought to be due to a T cell-mediated response to full-length Aβ (Orgogozo, 2003). Other anti-amyloid vaccines currently in clinical development include Vaxxinity's UB-311 and Araclon Biotech's Abvac 40.

[0005] Another known anti-Aβ vaccine, ACI-24, contains a 15-amino acid sequence that perfectly matches the sequence of human Aβ (WO2007 / 068411). This peptide antigen is conjugated to a liposomal carrier with the goal of stimulating antibodies against Aβ while avoiding meningoencephalitis and hemorrhage (Muhs, 2007; Pihlgren, 2013). The Aβ1-15 peptide was selected as the antigen based on the rationale that this sequence contains B cell epitopes but lacks the potent T cell reactive site of full-length Aβ (Monsonego, 2003). The latter is thought to be responsible for unwanted inflammatory responses. ACI-24 has been shown to act through the simultaneous activation of Aβ1-15-specific B cell receptors and Toll-like receptor 4 (TLR4), the latter of which is activated by the monophosphorylated lipid A (MPLA) adjuvant included in the ACI-24 vaccine (Pihlgren, 2013). B cells are activated, proliferate, and produce immunoglobulins (Ig) by cross-linking Ig receptors on the B cell surface.

[0006] To enhance antibody production, activated T helper cells provide a second signal via T cell epitopes. T cell epitopes presented by major histocompatibility complex (MHC) molecules (called human leukocyte antigens (HLA) in humans) on the surface of antigen-presenting cells (APCs) promote the differentiation of cognate T helper cells capable of producing IFNγ and IL-4. Cytokine release and costimulatory signals between activated T cells and B cells increase antibody responses and class switching. After initial vaccination, naive T cells proliferate and differentiate into effector cells. A small fraction of these cells form a pool of long-lived memory T cells that can rapidly proliferate upon re-encountering their cognate peptide after a booster vaccination (Sallusto, 2010). So-called "universal" T cell epitopes are specific for T cells present in the majority of the human population. They are typically derived from antigens to which humans are commonly exposed throughout their lifetime (e.g., tetanus, influenza, etc.). The ability of a T cell epitope to activate T cells is the result of at least two complementary properties: i) binding affinity to the HLA groove (strength of binding), and ii) the ability to bind indiscriminately to different HLA haplotypes (ability to cover a highly diverse human population with respect to differences in the expression of HLA molecules).

[0007] WO2019 / 197414 describes a vaccine composition containing an ACI-24 vaccine modified to contain a peptide containing a universal T cell epitope encapsulated within liposomes. WO2019 / 197414 reports that immunization of C57BL / 6 mice with the ACI-24 vaccine containing the T cell epitope induced elevated titers of Aβ1-42 oligomer-specific antibodies compared with the ACI-24 vaccine (without the T cell epitope). Preclinical studies have shown that the ACI-24 vaccine containing the T cell epitope generates a potent and sustained immune response. Furthermore, the induced antibodies were shown to bind to pyroglutamic amyloid beta, a highly neurotoxic form of Aβ that is a promising target for the treatment of Alzheimer's disease (Vukicevic, 2022).

[0008] Down syndrome (DS), also known as trisomy 21, is one of the most common causes of intellectual disability, affecting 1 in 800 newborns. The disorder is most commonly caused by a triplication of chromosome 21 (Belichenko, 2016). Patients with Down syndrome have distinctive facial features, impaired immune and endocrine systems, and delayed cognitive development. Significant advances in medical care and disease understanding have not only improved the quality of life for individuals with Down syndrome, but also significantly extended their lifespan. The mortality rate for individuals with Down syndrome is comparable to that of individuals with other intellectual disabilities up to the age of 35. However, after that age, the mortality rate for individuals with Down syndrome doubles every 6.4 years, compared with 9.6 years for individuals without Down syndrome. The average life expectancy for individuals with Down syndrome is 60 years, compared with 79 years for the general U.S. population. Summary of the Invention

[0009] A key feature of Down syndrome (DS) in adults is an increased risk of developing clinical symptoms similar to those of Alzheimer's disease (AD). AD is characterized by specific cognitive decline suggestive of a dementia diagnosis. Nearly all DS patients over the age of 40 exhibit neuropathological changes similar to those of AD, in the form of senile plaque formation and neurofibrillary tangles (Head, 2012). It is widely accepted that the neuropathology of AD-like cognitive decline involves the deposition of beta-amyloid (Aβ) peptides, followed by plaque formation, neurofibrillary tangles, vascular damage, neuroinflammation, and ultimately neuronal death. The amyloid protein precursor (APP) gene, which encodes the precursor protein of Aβ, is located on chromosome 21. In DS patients, all or at least part of chromosome 21 is present in triplicate. This results in three copies of the APP-encoding gene, leading to excess Aβ production. Increased Aβ protein production has been shown to correlate with AD-like symptoms not only in subjects with Down syndrome (DS) but also in the general population who develop AD (Head, 2012). These findings conclusively demonstrate that lifelong overexpression of wild-type APP causes cognitive decline in subjects with Down syndrome, similar to the amyloid cascade hypothesis used to explain AD. Down syndrome-associated AD is characterized by the presence of Alzheimer's disease neuropathological features (particularly including the accumulation of cerebral amyloid plaques and neurofibrillary tangles), and if brain lesions progress sufficiently, they can lead to the emergence of clinical symptoms such as cognitive decline and functional impairment.

[0010] Cognitive decline in individuals with Down syndrome (DS) occurs several years before a diagnosis of dementia. Cognitive decline is classified into three categories: mild, moderate, and severe. Mild cognitive decline is often characterized by significant memory impairment and behavioral changes that affect daily life. Moderate cognitive decline is characterized by increased memory loss, significant personality changes due to agitation and confusion, changes in sleep patterns, and the need for assistance with daily activities. Severe cognitive decline may mean loss of communication skills, significant physical impairment, and the need for full-time assistance with daily routines. By age 30, 28% of individuals with Down syndrome (DS) report symptoms such as apraxia and agnosia, as well as personality and behavioral changes (Head, 2012). Early Aβ deposition may be associated with subtle declines in episodic and executive function, termed mild cognitive impairment (Hartley, 2017). A recent study measuring brain amyloid burden in Down syndrome (DS) patients using the positron emission tomography tracer [11C]Pittsburgh compound B (PiB) showed that increased total amyloid-β concentrations were associated with declines in verbal episodic memory, visual episodic memory, executive function, and fine motor processing speed. DS patients who consistently had a PiB+ status showed worsening episodic memory, whereas patients who consistently had a PiB- status showed stable or improved performance (Hartley, 2017). Because cognitive decline in DS patients can mimic symptoms of intellectual disability, diagnosis can be challenging, and better diagnostic methods are being sought. Further complicating the diagnostic challenge is the fact that early symptoms do not manifest uniformly. For example, memory loss is an important early clinical symptom of dementia, but this is not the case in individuals with DS.

[0011] Current treatments for cognitive decline in Down syndrome (DS) are very limited, with the majority of research focused on dementia or Alzheimer's disease (AD). Therapies that have been investigated and shown promise for these indications (e.g., cholinesterase inhibitors) have so far shown limited efficacy in DS patients with cognitive decline (Prasher, 2002). In contrast to AD, Aβ-targeted immunotherapy has not been widely explored in DS.

[0012] WO2013 / 044147 and Belichenko (2016) report that Ts65Dn mice, a DS model, were vaccinated with a vaccine containing Aβ1-15 peptide embedded in liposomes.

[0013] Description of the Invention This invention arose from clinical trials of the ACI-24 vaccine, which contains an anti-amyloid beta (anti-Aβ) antigen (containing amino acids 1-15 of the human Aβ sequence), a universal T cell epitope, and an MPLA adjuvant in a liposomal formulation (ACI-24.060). This vaccine was able to induce anti-Aβ antibody responses in patients with AD (prodromal AD) without inducing any serious adverse events (SAEs) related to the study treatment. More specifically, initial interim results from the first cohort (prodromal AD patients) showed that when administered at 300 μg or 900 μg of antigen in prodromal AD subjects, the vaccine was able to induce anti-Aβ antibody responses by week 6, i.e., two weeks after the second vaccination. The following clinical observations were also observed: The safety and tolerability of the treatment was considered to be good. No serious adverse events related to study treatment were observed.

[0014] Accordingly, the present invention provides a method for inducing an anti-Aβ immune response in a human subject without inducing serious adverse events (i.e., serious adverse events resulting from the treatment), the method comprising administering to the human subject a liposomal vaccine composition comprising the following components: a. A beta amyloid (Aβ)-derived peptide antigen presented on the surface of a liposome, the peptide antigen comprising, consisting essentially of, or consisting of amino acids 1-15 of Aβ; b. a peptide containing a universal T cell epitope; c. Adjuvants containing monophosphoryl lipid A (MPLA) Here, the β-amyloid (Aβ)-derived peptide antigen is administered in an amount of 300 to 2000 μg.

[0015] Such a method can also be expressed in the form of a medical application. Accordingly, the present invention also provides a liposomal vaccine composition for use in inducing an anti-Aβ immune response in a human subject without inducing a serious adverse event (i.e., a treatment-induced SAE), the composition comprising: a. A beta amyloid (Aβ)-derived peptide antigen presented on the surface of a liposome, the peptide antigen comprising, consisting essentially of, or consisting of amino acids 1-15 of Aβ; b. Peptides containing universal T cell epitopes c. an adjuvant comprising monophosphorylated lipid A (MPLA); Here, the β-amyloid (Aβ)-derived peptide antigen is administered in an amount of 300 to 2000 μg.

[0016] Similarly, the present invention provides the use of a liposomal vaccine composition in the manufacture of a medicament for use in inducing an anti-Aβ immune response in a human subject without inducing serious adverse events (i.e., serious adverse events caused by the treatment), comprising the following components: a. A beta amyloid (Aβ)-derived peptide antigen presented on the surface of a liposome, the peptide antigen comprising, consisting essentially of, or consisting of amino acids 1-15 of Aβ; b. a peptide containing a universal T cell epitope; c. Adjuvants containing monophosphoryl lipid A (MPLA) Here, a peptide antigen derived from β-amyloid (Aβ) is administered in an amount of 300 to 2000 μg.

[0017] All embodiments described herein apply to such methods or medical applications, regardless of how they are expressed. Throughout this disclosure, the term "liposomal vaccine composition" is used. This term can be used interchangeably with "liposomal composition." These compositions are immunogenic and are also referred to as "liposomal immunogenic compositions."

[0018] As introduced above and further described herein, the liposomal compositions of the present invention have been demonstrated to be safe for administration to human subjects. These compositions are safe when administered at doses that produce a beneficial anti-Aβ immune response. Safety is measured (assessed) based on the absence of serious adverse events caused by the administration of the liposomal vaccine composition. A "serious adverse event" or "SAE" can be defined as any adverse event or adverse reaction that results in death, is life-threatening, requires hospitalization or an extension of an existing hospitalization, results in a persistent or significant disability or incapacity, or is a congenital anomaly or birth defect. In the definition of a serious adverse event, "life-threatening" refers to an event in which the subject was at risk of death at the time of the event. It does not refer to an event that, if more severe, would have resulted in death. Important adverse events / reactions that are not immediately life-threatening or do not result in death or hospitalization, but which may endanger the subject or require intervention to prevent any of the other outcomes described in the above definition, are also considered serious. Although medical judgment is required to interpret such events, researchers participating in human clinical trials can determine whether a serious adverse event occurred during the clinical trial and whether it was related (induced or caused) to the administration of the liposomal vaccine composition. This determination can be based on whether the event is considered possible or likely to have been caused by the administration of the liposomal vaccine composition. For the avoidance of doubt, it is possible that a particular subject may experience a serious adverse event that is not related (induced or caused) to the administration of the liposomal vaccine composition. This is not excluded by the present invention.

[0019] Specific serious adverse events (SAEs) that have not been induced (demonstrated to date) upon administration of the liposomal vaccine composition of the present invention include, but are not limited to, the following: Central nervous system inflammation or other serious undesirable reactions to the vaccine Meningoencephalitis

[0020] As mentioned above, in a previous study (Orgogozo, 2003), some patients developed inflammatory responses that were 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 by using the Aβ1-15-based liposome composition of the present invention. Aβ-specific T cell activation can be assessed using enzyme-linked immunosorbent spot (ELISpot). ELISpot is a type of assay that focuses on quantitatively measuring cytokine secretion frequency in single cells.

[0021] Amyloid-related imaging abnormalities (ARIA) are abnormal signals seen on neuroimaging in patients with Alzheimer's disease and may be observed with amyloid-modifying therapies. ARIA-E refers to cerebral edema, which is associated with disruption of the tight endorphin junction of the blood-brain barrier and subsequent fluid retention. ARIA-H refers to cerebral microhemorrhages (mH), which are small intracerebral hemorrhages often associated with hemosiderosis.

[0022] Unless otherwise specified, the dosage herein refers to a single dose of a beta amyloid (Aβ)-derived peptide antigen in a liposomal vaccine composition. Thus, unless otherwise specified, the dosage is expressed based on the tetrapalmitoylated Aβ1-15 peptide set forth herein and SEQ ID NO: 1. SEQ ID NO:1 - Tetrapalmitoylated Aβ1-15 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

[0023] When specific values ​​are specified, these values ​​are subject to manufacturing tolerances, as will be understood by those skilled in the art. Typically, specified doses cover a 15% variation on either side of the indicated value. For example, a specified dose of 1000 μg of β-amyloid (Aβ)-derived peptide antigen contains 850 to 1150 μg of β-amyloid (Aβ)-derived peptide antigen. The term "anti-Aβ immune response" refers to the production of anti-Aβ antibodies that bind to Aβ by a human subject in response to administration of a liposomal vaccine composition. Therefore, this response is also referred to as an anti-Aβ antibody response. The antibodies can include antibodies of the IgM isotype, preferably antibodies of the IgG isotype. The antibody response is typically polyclonal. This response can be measured in a suitable sample, such as a serum-containing sample, collected from a human subject. Thus, the sample can include or be derived from a blood sample. The antibodies preferably bind to a pathological form of Aβ, defined as a form of Aβ containing β-sheet multimers. Therefore, the produced antibodies can be 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 coating Aβ, such as Aβ1-42, on a solid support and then applying a sample from a human subject to the coating. A secondary antibody is used to detect binding of the antibody from the sample to the immobilized Aβ. Such a method may be quantitative. The secondary antibody may be an anti-Ig antibody, which can detect all isotypes. The secondary antibody may also be an anti-IgG antibody, which can measure Aβ-specific IgG titers.

[0024] Thus, according to all aspects of the present invention, the β-amyloid (Aβ)-derived peptide antigen (dosage expressed for tetrapalmitoylated Aβ1-15 as set forth in SEQ ID NO: 1) is administered in an amount of 300-2000 μg. This dosage combines favorable safety (including no induction of serious adverse events (SAEs)) with the ability to generate an anti-Aβ immune response. According to some embodiments, the β-amyloid (Aβ)-derived peptide antigen is administered in an amount of 300-2000 μg, preferably 300-1600 μg, preferably 300-1000 μg, and more preferably 300-900 μg. In certain embodiments, an amount of 300 μg of the β-amyloid (Aβ)-derived peptide antigen (dosage expressed for tetrapalmitoylated Aβ1-15 as set forth in SEQ ID NO: 1) is administered. In a specific embodiment, the β-amyloid (Aβ)-derived peptide antigen (dosage expressed for tetrapalmitoylated Aβ1-15 set forth in SEQ ID NO: 1) is administered in an amount of 900 μg. In another specific embodiment, the β-amyloid (Aβ)-derived peptide antigen (dosage expressed for tetrapalmitoylated Aβ1-15 set forth in SEQ ID NO: 1) is administered in an amount of 1600 μg. In a preferred embodiment, the β-amyloid (Aβ)-derived peptide antigen of SEQ ID NO: 1 (tetrapalmitoylated Aβ1-15) is administered in an amount of 300 to 1600 μg. In a preferred embodiment, the β-amyloid (Aβ)-derived peptide antigen of SEQ ID NO: 1 (tetrapalmitoylated Aβ1-15) is administered in an amount of 300 to 900 μg.

[0025] As will be readily understood by one of skill in the art, dosages can also be expressed based on the equivalent amount of Aβ1-15 alone (i.e., without lysine residues and palmitoylation), as described herein and as set forth in SEQ ID NO:2. SEQ ID NO:2-Aβ1-15 H-Asp-Ala-Glu-Phe-Arg-His-Asp-Ser-Gly-Tyr-Glu-Val-His-His-Gln-OH

[0026] The Aβ-derived peptide antigen is at least partially displayed on the outer surface of the liposome. As will be understood by those skilled in the art, "displayed on the surface of the liposome" means that the peptide is at least partially displayed on the outer surface of the (intact) liposome (see, e.g., Muhs, 2007; Pihlgren, 2013). This is typically achieved by insertion into the outer surface of the liposome or by other means by immobilization thereon. Insertion into the outer surface of the liposome can be facilitated by binding the Aβ-derived peptide antigen to a moiety that inserts into the outer surface of the liposome. The liposome can be any liposome suitable for displaying the Aβ-derived peptide antigen on its surface. Typically, this moiety includes a hydrophobic moiety to ensure insertion into the lipid bilayer of the liposome. This 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 beta amyloid (Aβ)-derived peptide antigen may be palmitoylated. A preferred configuration is one in which the Aβ-derived peptide antigen (Aβ(1-15)) is linked to two palmitoyl residues at the N- and C-terminal regions of the peptide. Thus, the peptide antigen is tetrapalmitoylated. This can be facilitated by incorporating two amino acid residues, such as lysine, at the N- and C-terminal regions of the Aβ-derived peptide antigen. The amino acid residue, such as lysine, is palmitoylated.

[0027] In some embodiments, the liposomes have a negative surface charge and are anionic. Preferably, the liposomes comprise phospholipids, more preferably, the phospholipids comprise dimylcitoylphosphatidylcholine (DMPC) and dimylcitoylphosphatidylglycerol (DMPG). The liposomes may further comprise cholesterol. In some embodiments, the molar ratio of these three components may be 9:1:7.

[0028] Thus, the most preferred compositions comprise Aβ-derived peptide antigens reconstituted in liposomes, and therefore, these compositions of the present invention are generally referred to herein as "liposomal vaccine compositions of the present invention."

[0029] Aβ-derived peptide antigens induce B cell responses in subjects. These are "B cell antigens." B cells are activated, proliferate, and produce immunoglobulin (Ig) by crosslinking immunoglobulin (Ig) receptors on the B cell surface. As previously described, Aβ plaques are formed by Aβ peptides 39–43 amino acids long. In their native, non-pathological form, these peptides have a random coil structure. During the transition to a pathological state, they convert to a predominantly β-sheet secondary structure and spontaneously aggregate into insoluble deposits. Aβ-derived peptide antigens may include, consist essentially of, or consist of amino acids 1–15 of Aβ, and are sometimes referred to as "Aβ(1–15)" (WO 2007 / 068411, ACI-24). In this context, the term "consisting essentially of" means that the Aβ-derived peptide antigen contains the 15 consecutive amino acids 1-15 of Aβ, but may contain a limited number of additional residues, such as four lysine residues to facilitate palmitoylation.

[0030] The Aβ-derived peptide antigen contained in the composition of the present invention has a secondary structure that mimics the pathological form of Aβ. Preferably, the Aβ-derived peptide antigen has a secondary structure that includes a β-sheet structure. More preferably, the Aβ-derived peptide antigen mainly has a β-sheet structure when presented on the liposome surface.

[0031] The Aβ-derived peptide antigens included in the compositions of the present invention are synthetic peptides. In some embodiments, the Aβ-derived peptide antigens are produced by chemical synthesis.

[0032] The liposomal vaccine composition contains a universal T cell epitope. The universal T cell epitope may be at least partially encapsulated in liposomes. A "universal T cell epitope" refers to an epitope specific for T cells present in the majority of the human population. These are typically derived from antigens to which humans are commonly exposed throughout their lives. Examples include antigens contained in routinely administered vaccines. Specific examples include T cell epitopes contained in tetanus, influenza, and diphtheria, as well as keyhole limpet hemocyanin (KLH) and Epstein-Barr virus (EBV). The "universal" ability of a T cell epitope to activate T cells is the result of at least two complementary properties: i) binding affinity to the HLA groove (meaning binding strength) and ii) indiscriminate binding to different HLA haplotypes (meaning the ability to cover a highly diverse human population with respect to differences in HLA molecule expression). A universal T cell epitope may bind to most of the MHC class II alleles present in the human population.Therefore, the universal T cell epitope contained in the vaccine composition of the present invention may be able to stimulate CD4 T cell responses.Therefore, the universal T cell epitope contained in the vaccine composition of the present invention may be able to stimulate helper T cell responses that enhance (Aβ-specific) antibody production by B cells.

[0033] A vaccine composition can contain two, three, or four different universal T cell epitopes. It is preferable that multiple different universal T cell epitopes are contained in the same peptide. Therefore, synthetic peptide constructs containing multiple different universal T cell epitopes are preferred. In certain embodiments, a peptide contains two, three, or four universal T cell epitopes. When a synthetic peptide construct contains at least two universal T cell epitopes, they can be linked by a linker. The linker is used to physically link the universal T cell epitopes to each other in a manner that does not impair the immunogenicity of the linked epitopes. Suitable linkers for linking amino acids to each other are well known in the art. Preferred linkers are themselves amino acid-based linkers, i.e., peptide linkers. Thus, they can link universal T cell epitopes to each other via peptide bonds. The linker allows for correct processing of the universal T cell epitopes. Antigen presentation by MHC class II molecules requires that antigens enter the endosomal-lysosomal compartment. These antigens are then processed by proteolytic enzymes, a significant subset of which includes lysosomal cysteine ​​proteases of the papain family. The resulting peptides bind to MHC class II molecules and are presented on the surface of professional antigen-presenting cells (APCs), such as macrophages, dendritic cells (DCs), and B cells (Lutzner and Kalbacher 2008). Therefore, the linker preferably contains a substrate for a lysosomal cysteine ​​protease of the papain family. The linker may also contain a substrate for one or more of cathepsin S, cathepsin B, and cathepsin L. In some embodiments, the linker comprises, consists essentially of, or consists of at least two or at least three amino acids. In some embodiments, the linker comprises, consists essentially of, or consists of the amino acids VVR, TVGLR, KVSVR, PMGAP, or PMGLP.

[0034] Thus, a peptide containing two universal T cell epitopes can be a linear peptide of the form: [Universal T cell epitope 1]-[Linker]-[Universal T cell epitope 2]

[0035] Thus, a peptide containing three universal T cell epitopes can be a linear peptide of the form: [Universal T cell epitope 1]-[Linker]-[Universal T cell epitope 2]-[Linker]-[Universal T cell epitope 3]

[0036] Thus, a peptide containing four universal T cell epitopes can be a linear peptide of the form: [Universal T cell epitope 1]-[Linker]-[Universal T cell epitope 2]-[Linker]-[Universal T cell epitope 3]-[Linker]-[Universal T cell epitope 4]

[0037] It should be noted that the linkers need not be identical between each pair of linked universal T cell epitopes. Thus, for example, the linker between universal T cell epitope 1 and universal T cell epitope 2 may be different from the linker between universal T cell epitope 2 and universal T cell epitope 3. In the case of four universal T cell epitopes, each of the three linkers may be different, or two may be the same and the third different (in any order). In some embodiments where the peptide includes multiple linkers, they are all identical.

[0038] In some embodiments, the universal T cell epitope is derived from diphtheria toxin, tetanus toxin, Epstein-Barr virus, influenza hemagglutinin, and / or keyhole limpet hemocyanin. Accordingly, preferred combinations of universal T cell epitopes are selected from the following: a. A combination of universal T cell epitopes from diphtheria toxin and tetanus toxin b. A combination of universal T cell epitopes from Epstein-Barr virus and tetanus toxin c. a combination of universal T cell epitopes from Epstein-Barr virus, tetanus toxin, and keyhole limpet hemocyanin; or d. A combination of influenza hemagglutinin, diphtheria toxin, tetanus toxin, and a universal T cell epitope from Epstein-Barr virus

[0039] Preferably, the liposomal vaccine composition employs a synthetic peptide construct comprising multiple distinct universal T cell epitopes linked by a peptide linker. Suitable universal T cell epitopes and peptides comprising multiple universal T cell epitopes include those described in WO2019 / 197414, which is incorporated herein by reference.

[0040] Peptides containing universal T cell epitopes can be synthesized by solid-phase synthesis. In some embodiments, peptides containing universal T cell epitopes can contain up to 85 amino acids. Optionally, peptides containing at least one T cell epitope can be up to 80, 75, or 70 amino acids in length. In some embodiments, peptides containing at least one T cell epitope can contain at least 10 amino acids. Using peptides containing at least 10 amino acids ensures that sufficiently immunogenic T cell epitopes are generated. Optionally, peptides containing at least one T cell epitope can contain 10 or more amino acids. For example, peptides containing at least one T cell epitope can contain at least 20, 30, or 40 amino acids. In other embodiments, peptides can contain 30-60 amino acids. This is based on the preferred minimum length per universal T cell epitope and the preference for peptides containing at least two, three, or four T cell epitopes.

[0041] Examples of suitable universal T cell epitopes include peptides comprising, consisting essentially of, or consisting of an amino acid sequence selected from SEQ ID NO: 8, SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 11, and SEQ ID NO: 12. The composition of these peptides is described in more detail with reference to Table 1 below.

[0042] [Table 1]

[0043] In one embodiment, the universal T cell epitope comprises, consists essentially of, or consists of an amino acid sequence selected from the group consisting of SEQ ID NO:8, SEQ ID NO:9, SEQ ID NO:10, SEQ ID NO:11, and SEQ ID NO:12, or an analog thereof. Analogs are functionally equivalent sequences with respect to their ability to stimulate T helper cells and may contain one or more modifications compared to the listed sequences. They may contain one or more (preferably one or two) additions, deletions, or substitutions, so long as their function as a universal T cell epitope is maintained. The minimum and maximum lengths of peptides are described above and apply mutatis mutandis to analogs. When a peptide comprises multiple T cell epitopes, the minimum length of the peptide is adjusted accordingly to maintain the function of each T cell epitope. In one embodiment, the universal T cell epitope comprises an amino acid sequence selected from the group consisting of SEQ ID NO:8, SEQ ID NO:9, SEQ ID NO:10, SEQ ID NO:11, and SEQ ID NO:12. In one embodiment, the universal T cell epitope consists essentially of or consists of an amino acid sequence selected from the group of SEQ ID NO:8, SEQ ID NO:9, SEQ ID NO:10, SEQ ID NO:11, and SEQ ID NO:12.

[0044] Combinations of these peptides can also be included in the vaccine compositions of the present invention. The combined peptides are preferably linked by one or more linkers as defined above.

[0045] For example, a peptide comprising a universal T cell epitope may comprise, consist essentially of, or consist of at least two universal T cell epitopes, each having an amino acid sequence selected from the group consisting of SEQ ID NO:8, SEQ ID NO:9, SEQ ID NO:10, SEQ ID NO:11, SEQ ID NO:12, or an analog thereof.

[0046] For example, a peptide containing a universal T cell epitope may contain two, three, or four universal T cell epitopes, each having an amino acid sequence selected from the group consisting of SEQ ID NO:8, SEQ ID NO:9, SEQ ID NO:10, SEQ ID NO:11, and SEQ ID NO:12.

[0047] In one embodiment, the T cell epitope comprises the amino acid sequence of SEQ ID NO: 8. In one embodiment, the T cell epitope comprises the amino acid sequence of SEQ ID NO: 9. In one embodiment, the T cell epitope comprises the amino acid sequence of SEQ ID NO: 11. In one embodiment, the peptide comprising the T cell epitope comprises the amino acid sequence of SEQ ID NO: 10. In another embodiment, the peptide comprising the T cell epitope comprises the amino acid sequence of SEQ ID NO: 12.

[0048] In one embodiment, the peptide comprising the T cell epitope comprises the amino acid sequence SEQ ID NO:11 and at least the amino acid sequence SEQ ID NO:8.

[0049] In one embodiment, the peptide comprising a T cell epitope comprises the amino acid sequence SEQ ID NO: 10 and at least one of the amino acid sequence SEQ ID NO: 9 and / or the amino acid sequence SEQ ID NO: 11. In one embodiment, the peptide comprising a T cell epitope comprises the amino acid sequence SEQ ID NO: 12 and at least one of the amino acid sequence SEQ ID NO: 9 and / or the amino acid sequence SEQ ID NO: 11.

[0050] In one embodiment, the peptide comprising a T cell epitope comprises the amino acid sequence SEQ ID NO: 10, the amino acid sequence SEQ ID NO: 9, and the amino acid sequence SEQ ID NO: 11. In one embodiment, the peptide comprising a T cell epitope comprises the amino acid sequence SEQ ID NO: 12, the amino acid sequence SEQ ID NO: 9, and the amino acid sequence SEQ ID NO: 11.

[0051] The universal T cell epitopes are preferably linked by one or more linkers, preferably peptide linkers, more preferably one or more linkers comprising, consisting essentially of, or consisting of the amino acids VVR, TVGLR, KVSVR, PMGAP, or PMGLP. In one embodiment, the linker comprises, consists essentially of, or consists of the amino acids VVR.

[0052] For example, a peptide comprising a universal T cell epitope may comprise, consist essentially of, or consist of at least two universal T cell epitopes, each having an amino acid sequence selected from the group consisting of SEQ ID NO: 8, SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 11, and SEQ ID NO: 12, wherein the universal T cell epitopes are linked by one or more linkers, preferably the one or more linkers comprise, consist essentially of, or consist of the amino acids VVR, TVGLR, KVSVR, PMGAP, or PMGLP, and more preferably the one or more linkers comprise, consist essentially of, or consist of the amino acids VVR.

[0053] In one embodiment, the peptide comprising a T cell epitope comprises the amino acid sequence SEQ ID NO:10, the amino acid sequence SEQ ID NO:9, and the amino acid sequence SEQ ID NO:11, wherein the universal T cell epitope is linked by one or more linkers comprising, consisting essentially of, or consisting of the amino acids VVR, TVGLR, KVSVR, PMGAP, or PMGLP, preferably VVR. In one embodiment, the peptide comprising a T cell epitope comprises the amino acid sequence SEQ ID NO:12, the amino acid sequence SEQ ID NO:9, and the amino acid sequence SEQ ID NO:11, wherein the universal T cell epitope is linked by one or more linkers comprising, consisting essentially of, or consisting of the amino acids VVR, TVGLR, KVSVR, PMGAP, or PMGLP, preferably VVR.

[0054] Examples of suitable peptides that contain multiple different universal T cell epitopes include peptides that comprise, consist essentially of, or consist of an amino acid sequence selected from the group consisting of SEQ ID NO: 3 (SAT42), SEQ ID NO: 4 (SAT43), SEQ ID NO: 5 (SAT44), SEQ ID NO: 6 (SAT47), and SEQ ID NO: 7 (SAT58). The composition of these peptides is described in more detail with reference to Table 2 below.

[0055] [Table 2]

[0056] In one embodiment, a peptide comprising a universal T cell epitope as used herein comprises, consists essentially of, or consists of an amino acid sequence selected from the group consisting of SEQ ID NO:5 (SAT44), SEQ ID NO:6 (SAT47), SEQ ID NO:7 (SAT58), SEQ ID NO:3 (SAT42), and SEQ ID NO:4 (SAT43), or an analog thereof. Analogs of these peptides are defined herein to take into account the fact that each peptide contains two to four distinct (universal) T cell epitopes. Thus, the minimum length of an analog herein is 20 to 40 amino acids (minimum length per T cell epitope is 10 amino acids) so that functionality of each T cell epitope is maintained. Peptides or analogs may incorporate alternative linker sequences, as described herein. Preferably, a peptide comprising a universal T cell epitope as used herein comprises, consists essentially of, or consists of an amino acid sequence selected from SEQ ID NO:5 (SAT44), SEQ ID NO:6 (SAT47), SEQ ID NO:7 (SAT58), or an analog thereof. In one embodiment, a peptide comprising a universal T cell epitope as used herein comprises, consists essentially of, or consists of an amino acid sequence selected from SEQ ID NO:6 (SAT47) and SEQ ID NO:7 (SAT58). In one embodiment, a peptide comprising a universal T cell epitope as used herein comprises, consists essentially of, or consists of the amino acid sequence of SEQ ID NO:7 (SAT58).

[0057] In one embodiment, the peptide containing a universal T cell epitope may be administered in an amount between 40 μg and 700 μg. Typically, the specified doses cover a 30% variation on either side of the indicated value. The peptide containing a universal T cell epitope may be included in 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 containing a β-amyloid (Aβ)-derived peptide antigen (represented by tetrapalmitoylated Aβ1-15 as set forth in SEQ ID NO: 1) administered at 900 μg (with a ±15% margin of error due to manufacturing tolerances) may contain a peptide containing a universal T cell epitope in an amount ranging from 270 μg (with a ±30% margin of error due to manufacturing tolerances) to 360 μg (with a ±30% margin of error due to manufacturing tolerances). Similarly, a liposomal vaccine composition in which a beta amyloid (Aβ)-derived peptide antigen (dosage represented as tetrapalmitoylated Aβ1-15 set forth in SEQ ID NO: 1) is administered in an amount of 300 μg (which may be + / - 15% to account for manufacturing tolerances) can contain a peptide containing universal T cell epitope adjuvant administered in an amount of 90 μg (which may be + / - 30% to account for manufacturing tolerances) to 120 μg (which may be + / - 30% to account for manufacturing tolerances). Similarly, a liposomal vaccine composition in which a beta amyloid (Aβ)-derived peptide antigen (dosage expressed for tetrapalmitoylated Aβ1-15 set forth in SEQ ID NO: 1) is administered in an amount of 1600 μg (which may vary by ±15% to account for manufacturing tolerances) can contain a peptide containing a universal T cell epitope adjuvant administered in an amount ranging from 470 μg (which may vary by ±30% to account for manufacturing tolerances) to 650 μg (which may vary by ±30% to account for manufacturing tolerances).

[0058] The liposomal vaccine composition includes an adjuvant containing monophosphoryl lipid A (MPLA) ("MPLA adjuvant"). Lipid A-based adjuvants are derived from lipopolysaccharides (chemically modified to reduce toxicity) and have been proven safe and effective. As used herein, the MPLA adjuvant is preferably synthetic monophosphoryl lipid A (MPLA). As defined herein, the term MPLA encompasses MPLA derivatives such as monophosphoryl hexaacyl lipid A, 3-deacyl (synthetic) (3D-(6-acyl) PHAD®), PHAD® (phosphorylated hexaacyl disaccharide), and MPL. The MPLA adjuvant may be a Toll-like receptor (TLR) agonist, particularly a TLR4 agonist. The purpose of the adjuvant is to enhance or stimulate an immune response in a subject. Preferably, at least one MPLA adjuvant forms part of the liposome and may form part of the lipid bilayer. The MPLA adjuvant can be presented at least partially on the outer surface of the liposome, by forming at least part of the outer layer of the lipid bilayer. Liposomes can effectively function as adjuvants with the addition of monophosphoryl lipid A (MPLA). The MPLA adjuvant typically forms part of the outer layer of the liposome. MPLA is typically added during liposome formation (as further described herein). Thus, a preferred liposome comprises dimylcitoylphosphatidylcholine (DMPC), dimylcitoylphosphatidylglycerol (DMPG), cholesterol, and MPLA. The molar ratio of these four components can be 9:1:7:0.05 in some embodiments.

[0059] In some embodiments of the present invention, the compositions of the present invention comprise two different adjuvants. Additional adjuvants that can be used in accordance with the present invention include aluminum hydroxide (alum) and / or CpG. In some embodiments, one or more MPLA adjuvants that form part of the liposomes can be combined with an encapsulating adjuvant. In other embodiments, one or more MPLA adjuvants that form part of the liposomes can be mixed with an additional adjuvant (such as alum or CpG) when forming the liposomes.

[0060] The MPLA adjuvant can be administered in amounts ranging from 15 to 600 μg. Typically, the specified doses cover a 40% variability on either side of the indicated value. The MPLA adjuvant can be included in the composition in a dose that correlates with the dose of the beta amyloid (Aβ)-derived peptide antigen. Thus, for example, a liposomal vaccine composition in which the beta amyloid (Aβ)-derived peptide antigen (dosage represented as tetrapalmitoylated Abeta 1-15 set forth in SEQ ID NO: 1) is administered in an amount of 900 μg (which may be between + / - 15% to account for manufacturing tolerances) can contain the MPLA adjuvant administered in an amount of 200 μg (which may be + / - 40% to account for manufacturing tolerances) to 270 μg (which may be + / - 40% to account for manufacturing tolerances). Similarly, a liposomal vaccine composition containing 300 μg of amyloid beta (Aβ)-derived peptide antigen (the dosage represented by tetrapalmitoylated Aβ1-15 set forth in SEQ ID NO: 1) administered at a dose of 300 μg (which may be ±15% to account for manufacturing tolerances) can contain 65 μg of MPLA adjuvant (which may be ±40% to account for manufacturing tolerances) or up to 90 μg of MPLA adjuvant (which may be ±40% to account for manufacturing tolerances). Similarly, a liposomal vaccine composition containing 1600 μg of amyloid beta (Aβ)-derived peptide antigen (the dosage represented by tetrapalmitoylated Aβ1-15 set forth in SEQ ID NO: 1) administered at a dose of 1600 μg (which may be ±15% to account for manufacturing tolerances) can contain 360 μg of MPLA adjuvant (which may be ±40% to account for manufacturing tolerances) or up to 480 μg of MPLA adjuvant (which may be ±40% to account for manufacturing tolerances). This dosage contributes to the safety and efficacy (with respect to the ability to generate an anti-Aβ immune response) of the liposome vaccine composition. In some embodiments, the MPLA adjuvant is administered at 15-600 μg, preferably 40-450 μg. Where specific values ​​are specified herein, these values ​​are subject to manufacturing tolerances, as will be understood by those skilled in the art.

[0061] In one embodiment, the present invention provides a liposomal vaccine composition comprising the following components: a. A β-amyloid (Aβ)-derived peptide antigen presented on the surface of a liposome, the β-amyloid (Aβ)-derived peptide antigen comprising, consisting essentially of, or consisting of amino acids 1-15 of Aβ, wherein the β-amyloid (Aβ)-derived peptide antigen is tetrapalmitoylated Aβ1-15 set forth in SEQ ID NO: 1; b. A peptide comprising a universal T-cell epitope consisting essentially of or consisting of Aβ, comprising the amino acid sequence of SEQ ID NO: 7 (SAT58), or an analog thereof; and c. An adjuvant comprising monophosphoryl lipid A (MPLA), preferably 3D-(6-acyl)PHAD®, for use in inducing an anti-Aβ immune response in a human subject without inducing serious adverse events, wherein the β-amyloid (Aβ)-derived peptide antigen is administered in an amount of 300 to 2000 μg, preferably 300 to 1600 μg, for example 300 μg, 900 μg or 1600 μg, preferably 300 μg or 900 μg.

[0062] In another embodiment, the present invention provides a liposomal vaccine composition comprising the following components: a. A β-amyloid (Aβ)-derived peptide antigen presented on the surface of a liposome, the β-amyloid (Aβ)-derived peptide antigen comprising, consisting essentially of, or consisting of amino acids 1-15 of Aβ, wherein the β-amyloid (Aβ)-derived peptide antigen is tetrapalmitoylated Aβ1-15 set forth in SEQ ID NO: 1; b. A peptide comprising a universal T-cell epitope consisting essentially of or consisting of Aβ, comprising the amino acid sequence of SEQ ID NO: 7 (SAT58), or an analog thereof; c. An adjuvant comprising monophosphoryl lipid A (MPLA), preferably 3D-(6-acyl)PHAD®.

[0063] In a preferred embodiment, the vaccine composition comprises a 300 μg amount of a β-amyloid (Aβ)-derived peptide antigen, a 90-120 μg amount of a peptide comprising a universal T-cell epitope, and a 65-90 μg amount of an MPLA adjuvant.

[0064] In another preferred embodiment, the liposome vaccine composition comprises a 900 μg amount of a beta amyloid (Aβ)-derived peptide antigen, a 270-360 μg amount of a peptide comprising a universal T cell epitope, and a 200-270 μg amount of MPLA.

[0065] In another preferred embodiment, the liposome vaccine composition comprises a β-amyloid (Aβ)-derived peptide antigen in an amount of 1600 μg, a peptide comprising a universal T-cell epitope in an amount of 470-650 μg, and MPLA in an amount of 360-480 μg.

[0066] The liposome vaccine compositions of the present invention can be synthesized by known means, see, e.g., WO2005 / 081872, WO2012 / 020124, WO2012 / 055933, and WO2013 / 044147, WO2019 / 197414, each of which is incorporated herein by reference.

[0067] The liposome vaccine composition can be administered to a subject by any suitable route of administration. As known to those skilled in the art, the vaccine composition can be administered topically, orally, rectally, nasally, or parenterally (e.g., intravenously, intradermally, subcutaneously, or intramuscularly). Furthermore, the vaccine composition can be incorporated into a sustained-release matrix, such as a biodegradable polymer, which is implanted near or adjacent to the desired delivery site. However, in a preferred embodiment, the vaccine composition is administered by injection, most preferably intramuscularly or subcutaneously. Typical volumes of injectable forms of the liposome vaccine composition range from 0.01 to 10 ml, e.g., 0.75 to 2.5 ml.

[0068] The liposomal vaccine composition can be administered to a subject once to generate a protective immune response. However, it is typically administered multiple times to the same subject. Therefore, the present invention can employ a so-called prime-boost regimen. Vaccine administration is typically performed with an intervening period of at least one week, often about one to twelve months. The safety and efficacy (in terms of the ability to generate an anti-Aβ immune response) of liposomal vaccine compositions has been confirmed when administered periodically over a long period of time. In some embodiments, the liposomal vaccine composition is administered once and then again one to four weeks later. As long as an appropriate interval is provided between doses, the liposomal vaccine composition can be administered two, three, four, five, six, seven, eight, nine, ten, ten, eleven, or twelve times over a 12-month period. The liposomal vaccine composition can be administered indefinitely, as long as an appropriate period of time is allowed between doses. An appropriate period of time is typically at least one week and often about one to twelve months. The period of time can be determined based on monitoring of the individual subject. Monitoring can include monitoring the subject's disease state and / or monitoring the subject's immune response level over time. Tests that can track the course of disease (e.g., MMSE, amyloid PET scan, or anti-Aβ immune response) are described herein. In prophylactic applications, the liposomal vaccine composition can be administered less frequently than therapeutic treatments and can be administered according to a regular schedule. Monitoring can be used in the context of prophylactic methods, for example, in subjects predisposed to developing an amyloid-β-related disease or condition, or a condition characterized by or associated with loss of cognitive memory.Suitable tests and biomarkers are described herein and include monitoring brain Aβ levels using amyloid PET scans (which may be lacking in early prevention), monitoring AD progression biomarkers such as tau, phosphorylated tau (e.g., pTau217, pTau181) and Aβ levels (Aβ1-42 and Aβ1-40) in blood and / or CSF, neurofilament light chain (NfL), glial fibrillary acidic protein (GFAP) in blood and / or CSF, measuring efficacy particularly on clinical / cognitive / functional parameters, and measuring immune responses in serum and / or CSF, including but not limited to anti-Abeta 1-42 IgM titers and / or anti-Abeta 1-42 IgG titers in blood and / or CSF.

[0069] When administration periods for vaccination regimens are described herein, the first administration of the liposomal vaccine composition is considered to be zero (0). In some embodiments, the liposomal vaccine composition is administered every 4 to 12 weeks for at least 48 weeks. For example, the liposomal vaccine composition can be administered in five separate administrations at weeks 0, 4, 12, 24, and 48. In another embodiment, the liposomal vaccine composition can be administered in six separate administrations at weeks 0, 4, 8, and 12, 24, 48, and 74.

[0070] In all dosing regimens, the liposome vaccine composition can be administered at a later time point, if desired. Typically, this is after completion of the initial dosing schedule ("Schedule"). Thus, this is sometimes referred to as a "booster" administration. Such additional administration may be administered at any appropriate time after completion of the initial dosing schedule, for example, 4, 12, 24, 26, 36, or 48 weeks after the last scheduled dose, or 1, 2, 2.5, 3, 3.25, 3.5, 4, 5, or more weeks after the last scheduled dose.

[0071] The liposomal vaccine composition can be administered so that an anti-Aβ immune response is induced after two administrations of the liposomal vaccine. Preferably, the liposomal vaccine composition is administered once and then again 2 to 6 weeks later, and preferably the second administration is administered 4 weeks after the first administration.

[0072] In a preferred embodiment, the liposome vaccine composition can be administered a third time 6 to 10 weeks after the second administration, preferably 8 weeks after the second administration.

[0073] As previously demonstrated, the liposomal vaccine composition induces an anti-Aβ immune response in a human subject without inducing serious adverse events. In some embodiments, administration of the liposomal vaccine composition results in a reduction in the amount of Aβ-associated plaques in the subject's brain, which can be measured by methods known in the art, such as PET scanning (e.g., using an appropriate amyloid tracer as discussed herein). The liposomal vaccine composition can be administered to a human subject for treatment, prevention, induction of a protective immune response against, or alleviation of symptoms associated with an amyloid-β-associated disease or condition or a condition characterized by or associated with loss of cognitive memory ability. Thus, the liposomal vaccine composition can be administered to a human subject for both prophylactic and therapeutic purposes.

[0074] The amyloid-β-related disease or condition may be a neurological disease, particularly Alzheimer's disease (AD). Other examples of amyloid-β-related diseases or conditions according to the present invention include mild cognitive impairment (MCI), Down's syndrome (DS), Down's syndrome-related Alzheimer's disease, cardiac amyloidosis, cerebral amyloid angiopathy (CAA), multiple sclerosis, Parkinson's disease, dementia with Lewy bodies, 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 the loss of cognitive memory ability. Thus, conditions characterized by or associated with loss of cognitive memory ability according to the present invention include Alzheimer's disease, mild cognitive impairment (MCI), Down's syndrome (including Down's syndrome-associated Alzheimer's disease), cardiac amyloidosis, cerebral amyloid angiopathy (CAA), multiple sclerosis, Parkinson's disease, dementia with Lewy bodies, amyotrophic lateral sclerosis (ALS), and inclusion body myositis (IBM).

[0075] The amyloid-β-related disease or condition may be a neurological disease, particularly Alzheimer's disease (AD). Other examples of amyloid-β-related diseases or conditions according to the present invention include mild cognitive impairment (MCI), Down's syndrome (DS), Down's syndrome-related Alzheimer's disease, cardiac amyloidosis, cerebral amyloid angiopathy (CAA), multiple sclerosis, Parkinson's disease, dementia with Lewy bodies, 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 the loss of cognitive memory ability. Thus, conditions characterized by or associated with loss of cognitive memory ability according to the present invention include Alzheimer's disease, mild cognitive impairment (MCI), Down's syndrome (including Down's syndrome-associated Alzheimer's disease), cardiac amyloidosis, cerebral amyloid angiopathy (CAA), multiple sclerosis, Parkinson's disease, dementia with Lewy bodies, amyotrophic lateral sclerosis (ALS), and inclusion body myositis (IBM).

[0076] In the case of AD, it has been observed that intervention as early as possible to detect the onset of cognitive impairment is most effective. Therefore, preventive administration may be advantageous, especially if other risk factors are present. In such embodiments, pre-treatment subjects may exhibit a lack of cognitive impairment consistent with a Mini-Mental State Examination (MMSE) score of approximately 30. For the avoidance of doubt, this score indicates the absence of cognitive impairment. The Mini-Mental State Examination (MMSE) (Folstein 1975) is well-known in the field and is the most commonly used test for complaints of problems with memory and other mental abilities, helping clinicians detect cognitive impairment and assess its progression and severity. The MMSE consists of a series of questions and tests, each of which is scored for correct answers. The MMSE tests various mental abilities, including memory, attention, and language ability. Scores range from 0 to 30, with 30 being the highest and 0 being the lowest.

[0077] Additionally, administration to human subjects with early-stage AD may also be beneficial. In some embodiments, the human subject, prior to treatment, exhibits cognitive impairment consistent with a Mini-Mental State Examination (MMSE) score of at least 18 (i.e., 18-30), e.g., 18-28, preferably at least 20 (i.e., 20-30), e.g., 20-28. In some embodiments, the human subject is suffering from AD, particularly early-stage AD. Such subjects may exhibit cognitive impairment consistent with an MMSE score of at least 20. Early-stage AD includes prodromal AD (also known as mild cognitive impairment due to AD) and mild AD. In some embodiments, the human subject is suffering from prodromal AD. In some embodiments, the human subject is suffering from mild AD. Such subjects may exhibit cognitive impairment consistent with an MMSE score of 20-28. In other embodiments, the subject is not suffering from severe (late-stage) AD. In further embodiments, the subject is suffering from early-stage AD, mild AD, mild-to-moderate AD, moderate AD, or non-severe AD. Such subjects may exhibit cognitive impairment consistent with an MMSE score of at least 12. The Clinical Dementia Rating Scale (CDR-GS) global score can also be used to define the severity of dementia in AD subjects using a 0-5 point scale (0 = none, 0.5 = doubtful, 1 = very mild, 2 = moderate, 3 = severe, 4 = very severe, 5 = end-stage). Generally, a CDR-GS score of 0 is associated with preclinical AD (asymptomatic AD stage), a score of 0.5 is associated with prodromal AD (Minor Cognitive Impairment due to AD), and a score of 1 is associated with mild AD dementia.

[0078] In certain embodiments, the subject has mild to moderate AD. Such subjects may exhibit cognitive impairment consistent with an MMSE score of 12 to 28. In specific embodiments, the subject has moderate Alzheimer's disease (AD). Such subjects may exhibit cognitive impairment consistent with an MMSE score of 12 to 19. Another factor that may be considered when selecting a subject for treatment is age: for example, the subject may be 40 years of age or older.

[0079] As previously mentioned, a key feature of adult patients with Down syndrome (DS) is their increased risk of developing clinical symptoms (in addition to AD pathology) that resemble Alzheimer's disease (AD). AD is characterized by declines in specific cognitive domains, and in its most advanced stages, suggests a diagnosis of dementia. Nearly all DS patients over the age of 40 exhibit neuropathological changes similar to AD in the form of senile plaque formation and neurofibrillary tangles (Head, 2012). Therefore, when referring to the treatment, prevention, induction of a protective immune response, slowing of symptom progression, or alleviation of DS-related symptoms, it is intended to refer to AD-like symptoms in DS patients. Preventive treatments can also be applied to patients without evidence of β-amyloid plaque formation and neurofibrillary tangles. As previously mentioned, studies using the positron emission tomography tracer [11C]Pittsberg compound B (PiB) to measure brain amyloid burden in Down syndrome (DS) patients have shown that increased total amyloid-β levels are associated with declines in verbal episodic memory, visual episodic memory, executive function, and fine motor processing speed. DS patients who were consistently PiB+ demonstrated worsening episodic memory, whereas patients who were consistently PiB- demonstrated stable or improved performance (Hartley, 2017). Therefore, preventive treatment may be indicated for patients who are PiB- or who are shown to be amyloid-negative using other amyloid PET tracers (e.g., florbetaben). Conversely, therapeutic treatment may be indicated for patients who have evidence of beta-amyloid plaque formation and neurofibrillary tangles and / or who are PiB+ or who are shown to be amyloid-positive using other amyloid PET tracers (e.g., florbetaben). DS is a population at high risk for AD-like disease. DS offers an opportunity to explore effective treatments for AD that benefit both DS and the general population. The homogeneity of etiology, age-related onset, and lack of other dementias strongly support prevention trials of AD-like symptoms in DS. The focus in DS subjects is preventive therapy. Biomarker endpoints of Alzheimer's disease pathology may be employed to monitor treatment.Examples include, but are not limited to, Aβ levels, total tau, phosphorylated tau protein, soluble amyloid precursor protein α (sAPPα), soluble amyloid precursor protein β (sAPPβ), orexin A, neurofilament light chain (NfL), GFAP, inflammatory cytokines, angiogenic proteins, vascular damage markers in plasma and / or cerebrospinal fluid, and TLR-4 expression. PET scan imaging may also be used. For example, positron emission tomography (PET) tracers [11C]Pittsberg compound B (PiB), florbetapir, or florbetaben have been used to measure cerebral amyloid burden in patients with Down syndrome (DS) (Hartley, 2017). Other potential uses include tau positron emission tomography tracers such as flortaucipir and PI-2620. Free, total, and combined IgG antibody titers can be measured. Free IgM, total IgM, and composite IgM antibody titers can be measured. Clinical efficacy can be measured by, among other things, 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, Directed Recall Test (CRT) or its modified version (mCRT), Cambridge Cognitive Assessment for Down Syndrome (CAMCOG-DS), modified Selective Recall Test (SRT), NeuroPSYchological Assessment-II-Train and Car Subtest (NEPSY-II), Kaufman Brief Intelligence Scale-2 (KBIT-2)), Brief Practice Test (BPT4), behavior (e.g., Vineland Adaptive Behavior Scales (VABS), Neuropsychiatric Inventory (NPI)), and assessment of progression to dementia (e.g., Dementia Screening Questionnaire for Intellectual Disability (DSQIID)).

[0080] Assessment using the MMSE may not be appropriate for human subjects with Down syndrome (DS). Similarly, age-related considerations may differ (e.g., due to shorter life expectancy). Male or female subjects with Down syndrome (DS), regardless of age, may be specifically eligible for preventive treatment. As previously mentioned, preventive treatment may be indicated for subjects without evidence of beta-amyloid plaque formation and neurofibrillary tangles. Conversely, therapeutic treatment may be indicated for subjects with evidence of beta-amyloid plaque formation and neurofibrillary tangles. Human subjects with Down syndrome (DS) may be in the preclinical stage of AD without amyloid-related cognitive decline. Treated subjects may be 50 years of age or younger, such as 45, 40, 35, 30, or 25 years of age or younger. Treatable subjects with Down syndrome (DS) 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 revision 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, the DSM serves as the primary authority on psychiatric diagnosis.

[0081] According to some embodiments, a treatable subject may be identified by a PET scan that shows positive Aβ deposits. Such Aβ deposits are found not only in patients with early AD (mild cognitive impairment due to AD and mild AD) but also in patients with more advanced AD, such as moderate AD. For example, florbetaben positron emission tomography (PET) can be used to examine the amount of amyloid in the brain. According to some embodiments, a treatable subject may be identified by a PET scan that shows positive tau aggregates. For example, positron emission tomography (PET) using a tau tracer, such as PI-2620, can be used to examine tau accumulation in the brain.

[0082] Potential subjects for treatment can be identified based on their CDR score. The Clinical Dementia Rating Scale (CDR scale) is a numerical scale used to quantify the severity (i.e., "stage") of Alzheimer's disease (AD) symptoms. This system, developed at the University of Washington School of Medicine (Hughes et al., 1982), involves a semi-structured interview conducted by a qualified medical professional to assess a subject's cognitive and functional performance in six areas: memory, orientation, judgment and problem-solving skills, community involvement, home and hobbies, and personal care. These scores can be combined to obtain a composite score (called the Sum of Boxes (CDR-SB)) ranging from 0 (no symptoms) to 3 (severe symptoms). Therefore, CDR-SB scores range from 0 to 18 points. A CDR-SB score of 0 may identify a subject as normal. Such subjects may be eligible for preventive treatment, even if other risk factors are potentially present. A CDR-SB score of 0.5-2.5 may identify a subject as having prodromal AD or MCI. A CDR-SB score of 2.5-4.0 may identify a subject as having very mild AD. A CDR-SB score of 4.5-9.0 may identify a subject as having mild AD. A CDR-SB score of 9.5-15.5 may identify a subject as having moderate AD. A CDR-SB score of 16.0-18.0 may identify a subject as having severe AD. See O'Bryant et al., Arch Neurol. 2010;67(6):746-749. doi:10.1001 / archneurol.2010.115. As previously mentioned, administration to subjects with early-stage disease (cognitive impairment or AD) may also be beneficial. Thus, in some embodiments, the subject exhibits cognitive impairment prior to treatment consistent with a CDR-SB score of 15.5 or less (eg, between 0.5 and 15.5), or 9.0 or less (eg, between 0.5 and 9.0).

[0083] In certain embodiments, the subject suffers from mild Alzheimer's disease (AD). A subject suffering from mild Alzheimer's disease (AD) may have prodromal AD, early AD, mild AD, mild to moderate AD, or moderate AD. Such a subject may exhibit cognitive impairment consistent with an MMSE score of 12 to 28. Such a subject suffering from mild Alzheimer's disease (AD) may have a CDR-SB score of less than 16.0. The Clinical Dementia Rating Scale (CDR-GS) global score can also be used to define the severity of dementia in an AD subject, using a 0-5 point scale (0 = absent, 0.5 = doubtful, 1 = present but mild, 2 = moderate, 3 = severe, 4 = severe, 5 = end-stage). Generally, a CDR-GS score of 0 is associated with preclinical AD (asymptomatic AD stage), a score of 0.5 with prodromal AD (MCI due to AD), a score of 1 with mild AD dementia, and a score of 2 with moderate dementia.

[0084] The liposomal vaccine composition can be administered to a human subject receiving at least one additional therapy, preferably selected from an acetylcholinesterase inhibitor (ACHEI) and / or memantine. [Brief explanation of the drawings]

[0085] [Figure 1] Anti-Abeta 1-42 IgG antibody titers in the serum of monkeys immunized with ACI-24EE (group 1, filled circles) or ACI-24.060 (group 2, squares) are shown. [Figure 2] Anti-Abeta 1-42 IgG antibody titers in the cerebrospinal fluid of individual monkeys immunized with ACI-24EE (group 1, circles) or ACI-24.060 (group 2, squares) are shown before administration and at necropsy (day 183). [Figure 3] Figure 3 shows images of labeled Aβ plaques in brain sections from AD patients incubated with serum from monkeys immunized with CI-24.060 (Figure 3a: monkey serum pool before administration, Figure 3b: monkey serum pool at day 92). [Figure 4]OD values ​​are shown for the results of anti-pyroglutamate Abeta 3-42 IgG ELISA using serially diluted sera from monkeys immunized with CI-24.060 (gray triangles) and donanemab (black squares). [Figure 5] 1 shows the results of ECL values ​​of anti-Abeta 1-42 oligomeric IgG MSD using serially diluted sera from monkeys immunized with ACI-24.060 (gray triangles) and donanemab (black squares). DETAILED DESCRIPTION OF THE INVENTION

[0086] [Table A]

[0087] The invention will be further understood with reference to the following non-limiting examples.

[0088] Definition: The MMSE (Folstein 1975) is a widely used comprehensive cognitive function test that assesses memory, orientation, and behavior in a short battery of tests. Scores range from 0 to 30, with 30 being the best score and 0 being the worst.

[0089] The Clinical Dementia Rating Scale (Hughes et al. 1982) is a comprehensive scale that assesses the functioning of patients with Alzheimer's disease (not simply functional assessment, but cognitive function as well as memory) in six categories: memory, orientation, judgment and problem-solving ability, community activities, home and hobbies, and personal care. It is based on semi-structured interviews conducted with patients and caregivers by assessors who do not have access to the results of the cognitive tests mentioned above. Each category has a score ranging from 0 (no symptoms) to 3 (severe), and the sum of these items (sum of boxes) ranges from 0 to 18 points.

[0090] Patients with early Alzheimer's disease include those with mild cognitive impairment (MCI) due to Alzheimer's disease and mild Alzheimer's disease.

[0091] According to the National Institute on Aging-Alzheimer's Disease Association (NIA-AA) criteria, mild cognitive impairment due to Alzheimer's disease is defined as evidence of intrapersonal decline manifested as a change from a previously achieved cognitive level by self-report or informant report and / or clinician judgment, decline in cognitive function in at least one domain (not necessarily episodic memory) compared with age- and education-matched norms (decline in multiple cognitive domains is acceptable), preserved independence of functional abilities, absence of dementia, and clinical findings consistent with the Alzheimer's disease phenotype in the absence of other conditions that may cause dementia.

[0092] According to the NIA-AA criteria, suspected AD dementia meets the criteria for dementia and also has the following key features: insidious onset (symptoms develop gradually over months to years rather than suddenly over hours or days), a clear history of reported or observed cognitive deterioration, and the history and examination reveal initial and most prominent cognitive impairment in one of the following categories: amnesic symptoms (the most common syndromic symptom of AD dementia. Impairments should include learning impairment and difficulty recalling recently learned information. There should also be evidence of cognitive impairment in at least one other cognitive domain); non-amnesic symptoms: language symptoms (the most prominent impairment is word finding, but impairments in other cognitive domains should also be present); visuospatial presentation (the most prominent impairment is spatial cognitive functions such as object agnosia, impaired face recognition, simultaneity agnosia, and dyslexia, and impairments in other cognitive domains should also be present); and executive dysfunction (the most prominent impairment is impairments in reasoning, judgment, and problem-solving. Impairments in other cognitive domains should also be present).

[0093] Patients with early-stage AD are those with an MMSE score of 20 or more (≥20 points). This includes patients with mild cognitive impairment (MCI) due to AD and patients with mild AD.

[0094] Mild AD patients were those with an MMSE score of 20-28.

[0095] Patients with mild to moderate AD were those with an MMSE score of 12 to 28.

[0096] Patients with moderate AD were those with an MMSE score of 12-19. [Example]

[0097] Example Example 1: Preparation of liposomal vaccine composition ACI-24.060 Step 1: Synthesis and purification of T cell epitope peptides The SAT58 T cell epitope-containing peptide was prepared by linear solid-phase peptide synthesis (SPPS) using 2-chlorotrityl resin with standard Fmoc chemistry. The standard coupling procedure involved 3.0 equivalents of amino acid (SAT58 peptide) and coupling reagent in the presence of 3.0 equivalents of base in DMF at room temperature for at least 1 hour. For difficult sequences, double coupling was performed with extended reaction times. After amino acid coupling was complete, an acetylation capping step was introduced using 5.0 equivalents of Ac20 (acetic anhydride) in pyridine to prevent unwanted peptide chain elongation. The resin was washed with DMF, and the Fmoc group was removed by reaction with 20% piperidine in DMF for 5 minutes. After SPPS, global deprotection and peptide cleavage from the resin were performed using a standard cleavage cocktail (TFA / TIS / water / TBMTP) for a minimum of 2 hours at room temperature. The crude product was then precipitated with a 10-fold excess of cold isopropyl ether / heptane, washed with IPE, and the solid was filtered through a glass frit and dried under vacuum. The crude peptide was purified on a reverse-phase C18 column using a preparative HPLC system with a gradient of solvent A (water, 0.1% TFA) and solvent B (acetonitrile, 0.1% TFA). HPLC fractions containing the desired peptide with a purity greater than 90% were pooled together, diluted with water, and subjected to ion exchange. The desired ion-exchanged fraction was lyophilized to obtain a powder. The identity and purity of the final peptide were characterized and confirmed by HPLC-MS analysis.

[0098] Preparation of ACI-24.060 vaccine (cross-flow injection method) Lipids (DMPG, DMPC, cholesterol, and 3D-(6-acyl)PHAD® (Avanti Polar Lipids, USA)) were dissolved in 96% EtOH (ethanol) in a heating cabinet at 60°C. After the lipids were completely dissolved, the solution was filtered through a 0.2 μm pore size filter and injected into an injection system heated to 60°C. Specifically, an appropriate amount of SAT58 was dispersed in EtOH by sonication at room temperature (the EtOH concentration was typically 2% v / v of the final SAT58 solution) to prepare a peptide slurry. This was then diluted with His-sucrose buffer (10 mM histidine, 250 mM sucrose) for solubilization. The SAT58 solution was filtered through a 0.2 μm pore size filter, placed in an injection vessel, and heated to 40°C. When the lipid / EtOH solution and the SAT58 solution mixed, liposomes formed at the injection site. Immediately after liposome formation, the EtOH concentration was reduced by online dilution with 10 mM histidine and 250 mM sucrose. The intermediate liposomes were extruded through a 100 nm pore size polycarbonate membrane at room temperature. EtOH was removed by ultrafiltration / diafiltration (UDF) using hollow fiber membranes (MWCO: 500 kD) and the buffer was exchanged with PBS pH 6.9. SAT58 liposomes were then diluted with dispersion buffer (PBS pH 6.9) to a total lipid concentration of 1 mg / mL and warmed to 35°C. Pal1-15 was dissolved in a 10% w / v beta-OG solution in 10 mM NaHPO pH 11.4 buffer at 60°C and further diluted with the same buffer to a final concentration of 1 mg / mL. After mixing these two solutions using a cross-flow injection module, the liposome suspension was further incubated at 35°C with stirring to allow complete insertion of Pal1-15. A second UDF step using a hollow fiber membrane (MWCO: 500 kD) was performed to remove beta-OG and exchange the buffer for 10 mM histidine and 250 mM sucrose. The product was filtered through a 0.2 μm Acrodisc mPES syringe filter. The final product was prepared by appropriate dilution using 10 mM histidine / 250 mM sucrose buffer, sterile filtered through a 0.2 μm sterilizing-grade filter, and then aseptically filled into sterile glass vials, sealed, and stored at 2–8°C. [Example]

[0099] Example 2. Safety and Efficacy in Humans in a Phase 1b / 2 AD Study Test purpose: The overall objective of this Phase 1b / 2 multicenter, adaptive, double-blind, randomized, placebo-controlled trial (ACI-24-AD-DS-2102) is to evaluate the safety, tolerability, immunogenicity, and pharmacodynamic effects of ACI-24.060 in adults with prodromal Alzheimer's disease (AD) and Down syndrome. The study will be conducted in two parts. Part 1 will be conducted in adults with prodromal Alzheimer's disease (AD). Part 2 will be conducted in adults with Down syndrome (DS).

[0100] Part 1 (prodromal AD) testing: Main purpose: To evaluate the safety and tolerability of ACI-24.060. Secondary Objectives: To evaluate the anti-amyloid beta (Aβ) antibody response in serum generated by ACI-24.060. Exploratory purpose: -Positron emission tomography (PET) scans will be used to examine the effect of ACI-24.060 on amyloid levels in the brain. -To examine the effect of ACI-24.060 on brain tau levels using PET imaging. · Examine the effects of ACI-24.060 on behavioral, cognitive, and clinical functioning. -Examine the correlation between the degree of anti-Aβ antibody response and changes in biomarkers such as amyloid PET, volumetric magnetic resonance imaging (MRI), and advanced MRI sequences, as well as behavioral, cognitive, and clinical function. To investigate the influence of baseline demographic factors, such as subject age, apolipoprotein E (ApoE) genotype, and gender, on the effects of ACI-24.060 on test parameters. To investigate the effect of ACI-24.060 on MRI (volumetric MRI and advanced MRI sequences) changes. -Investigate AD-related biomarkers and immunogenicity associated with ACI-24.060 in collected test fluids.

[0101] Testing in Down Syndrome Part 2: Main purpose: To evaluate the safety and tolerability of ACI-24.060. -To evaluate anti-Aβ antibody responses in serum induced by ACI-24.060. Secondary Objectives: To evaluate the pharmacodynamic effects of ACI-24.060 on amyloid-related fluid biomarkers. PET scans will be used to assess the effect of ACI-24.060 on amyloid levels in the brain. Exploratory purpose: ·Evaluate the impact of ACI-24.060 on behavioral, cognitive, and clinical functioning. To investigate the influence of baseline demographic factors, such as subject age, ApoE genotype, and gender, on the test parameters of ACI-24.060. -Investigate the correlation between the degree of anti-Aβ antibody response and changes in biomarkers such as amyloid PET, volumetric MRI, behavior, cognitive function, and clinical function. To investigate the effect of ACI-24.060 on MRI (volumetric MRI and advanced MRI sequences) changes. - Using tau PET imaging, we will investigate the effect of ACI-24.060 on brain tau levels. To investigate the effect of baseline AD clinical status on ACI 24.060 test parameters in Down syndrome (DS). To investigate the effect of baseline intellectual disability on ACI 24.060 test parameters. To investigate biomarkers associated with AD in Down syndrome (DS) and immunogenicity associated with ACI-24.060 in collected test fluids.

[0102] Test Part 1: Part 1 of the study will be conducted to evaluate the effects of the study medication (ACI-24.060 or placebo) administered for 48 weeks in subjects with prodromal AD. Interim analysis (IA): In each cohort, multiple IAs for safety, tolerability, and immunogenicity will be conducted in some or all of the AD subjects at different study time points during treatment and follow-up. The first IAs for safety and tolerability will be conducted 2 weeks after the second study drug administration (i.e., W6), after data collection for the first 4 subjects was completed.

[0103] Exam Part 2: Part 2 of the study will be conducted to evaluate the effects of the study drug (ACI-24.060 or placebo) administered over 74 weeks in 88 adult subjects with Down syndrome (DS) and no dementia who have amyloid pathology confirmed by PET scan. Interim analysis: Interim analyses of safety, tolerability, and immunogenicity may be performed at different pre-specified time points during the study and follow-up period. The first interim analysis of safety and tolerability will be conducted no earlier than 2 weeks after the second dose of study drug (i.e., W6).

[0104] Number of subjects: Test Part 1: In Part 1 of the study, up to 88 AD patients can be randomized and initiated into up to four cohorts (AD1-AD4). Each cohort will initially include four AD patients, with a 3:1 active / placebo ratio. Any of the AD cohorts can be expanded. Exam Part 2: In Part 2 of the study, up to 88 patients with DS can be randomized and initiated in up to three cohorts (DS1-DS3). Each cohort will initially contain four to eight patients with DS, with a 3:1 active / placebo ratio. 72 patients with DS will be randomized to one of the three cohorts, with an overall 2:1 active / placebo ratio. 48 patients will receive ACI-24.060 and 24 will receive placebo, accounting for an expected dropout rate of approximately 15%. Study population: Research Part 1: The study population consisted of men and women aged 50 to 85 years with prodromal AD (mild cognitive impairment [MCI] due to AD) who had amyloid pathology confirmed by PET scan.

[0105] Study Part 2: The study population consisted of men and women with Down syndrome (DS) aged 35 to 50 years who were dementia-free and had amyloid pathology confirmed by PET scan.

[0106] Inclusion Criteria: Research Part 1 1. Age between 50 and 85 at the time of screening. 2. Diagnosis of prodromal AD: MCI due to AD according to the National Institute on Aging-Alzheimer's Disease Association (NIA-AA) criteria. 3. The presence of amyloid pathology is confirmed by PET scan at screening. 4. Clinical Dementia Rating (CDR) global score of 0.5. 5. Subjects must be able to understand the details of this study and provide written informed consent, as determined by the investigator. 6. Subjects must not be taking any commercially available AD medications or must be receiving a stable dose of an acetylcholinesterase inhibitor (ACHEI) and / or memantine for at least 2 months prior to baseline. 7. The subject is cared for by a trusted spouse, informant, or study partner to ensure compliance, assist with clinical evaluations, and report safety issues, and the spouse, informant, or study partner agrees to serve in this role. 8. Women who are postmenopausal for more than 1 year or surgically sterilized, or women of childbearing potential or who are not postmenopausal, must have a negative blood pregnancy test at screening and be willing to use highly effective contraception from the screening visit until the end of participation. Male participants with female partners of childbearing potential must use a barrier method (spermicide condom) during the study in addition to the contraception used by their female partners. 9. Subjects and study partners must be fluent in the official language of their country of residence and able to comply with all study procedures, including lumbar puncture.

[0107] Exam Part 2 1. Age ≥ 35 years and ≤ 50 years at screening (subjects ≥ 35 years and ≤ 39 years are considered eligible if they have Down syndrome (DS) and previous amyloid-positive findings consistent with AD pathology on PET scan and / or body fluid testing). 2. Male or female subjects with Down syndrome (DS) with a cytogenetic diagnosis of either trisomy 21 or a complete unbalanced translocation of chromosome 21. 3. PET scan at screening demonstrates the presence of amyloid pathology. 4. The subject, their legal representative (if applicable), and / or study partner, at the discretion of the investigator, understands the details of the study and is able to provide written informed consent before commencing any study-related activities. 5. At the investigator's discretion, the subject, their legal representative (if applicable), and / or their study partner or informant will be able to fully participate in this study and will have a sufficient understanding of the official language of their country of residence to ensure completion of study assessments. 6. Women who are postmenopausal for more than 1 year and / or surgically sterilized, or women of childbearing potential or who are not postmenopausal, must have a negative blood pregnancy test at screening and be willing to use highly effective contraception from the screening visit through the end of the study. Male participants with female partners of childbearing potential must use a barrier method (spermicide condom) during the study in addition to the contraception used by their female partners. 7. Mild to moderate intellectual disability according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) classification. 8. Subject must have a research partner who, at the discretion of the investigator, will have direct and regular contact with the subject for at least 10 hours per week and who can provide reliable answers to questions about the subject.

[0108] Dosage and duration: The investigational drug will be administered by intramuscular injection.

[0109] Clinical Trial Part 1: The initial dose of ACI-24.060 to be tested is 300 μg. For dose escalation, the next higher dose cannot be increased by more than three times, i.e., 900 μg. The maximum dose of ACI-24.060 to be tested is 1600 μg. Randomized AD subjects will receive five injections of the study drug (ACI-24.060 or placebo) on W0, W4, W12, W24, and W48. Dosing regimens may need to be modified to the same or different doses to optimize immunogenicity. Each subject will have a 26-week follow-up period after the treatment period. The overall study participation period for AD subjects is approximately 80 weeks (maximum 6-week screening period, 48-week treatment period, and 26-week follow-up period). Exam Part 2: Randomized DS subjects will receive the first five injections (ACI-24.060 or placebo) at W0, W4, W12, W24, and W48 on the same schedule as administered in Part 1, plus an additional injection at W74 at a dose previously shown to be safe and immunogenic in AD subjects in Part 1.

[0110] The dose of ACI-24.060 in the DS study population may need to be adjusted based on immunogenicity and safety / tolerability IA data obtained from the first 4-8 DS patients. The initial dose of ACI-24.060 tested will be the dose previously shown to be safe and immunogenic in AD patients in Part 1 of this study (i.e., 300 μg of ACI-24.060). The maximum dose of ACI-24.060 tested will be 1600 μg. Each subject will have a 26-week follow-up period after the treatment period. The total study participation period for DS patients will be approximately 106 weeks (maximum 6-week screening period, 74-week treatment period, and 26-week follow-up period).

[0111] As of January 19, 2024, 43 AD patients had been randomized to the study: 8 received ACI-24.060 300 micrograms or placebo (AD1 cohort), 29 received ACI-24.060 900 micrograms or placebo (expanded AD2 cohort), and 6 received ACI-24.060 1600 micrograms or placebo (AD3 cohort).

[0112] Safety and tolerability in this study have been favorable to date, with most adverse events being mild, no serious adverse events (suspected or likely related to the study vaccine), no adverse events leading to study discontinuation, no abnormalities found on MRIs performed after the start of study treatment, and no cases of ARIA-E have been reported. As of January 19, 2024, two serious adverse events (SAEs) have been reported in one subject in the AD2 cohort who received either ACI-24.060 or placebo at a dose of 900 μg. The subject was hospitalized for nephrectomy for removal of a clear cell renal tumor. The subject also experienced complete atrioventricular block during anesthesia induction, requiring placement of a pacemaker. The causality of these events is considered unrelated or unlikely to be related to the study vaccine, according to the investigator.

[0113] Data from an interim analysis conducted to date indicates that ACI-24.060 at doses of 300 μg and 900 μg can induce anti-Aβ antibody responses in subjects starting two weeks after the second dose, i.e., week 6. Data indicate that ACI-24.060 vaccination has so far been safe and well tolerated. [Example]

[0114] Example 3. Chronic Toxicity Test: The safety and immunogenicity of ACI-24.060 were evaluated in non-human primates (NHPs), specifically cynomolgus monkeys, which are a suitable species for evaluating vaccine immunogenicity due to their evolutionary closeness to the human immune system.

[0115] 3.1 Study design Healthy cynomolgus monkeys (Macaca fascicularis), nine males and nine females (18 animals in total), were used in this study. The animals were 2 to 3 years old, and weighed 2.7 to 4.4 kg for males and 2.8 to 3.4 kg for females. The monkeys were divided into two groups as shown in Table 3.

[0116] [Table 3]

[0117] Two groups were immunized seven times with ACI-24EE (placebo, group 1) or ACI-24.060 (group 2) by intramuscular (im) administration on days 1, 29, 57, 85, 113, 141, and 169.

[0118] 3.2 Toxicity assessment: Safety assessments were based on clinical observations, food consumption, post-dose observations, body weight, injection site evaluation, ophthalmology, electrocardiography, blood pressure, clinical pathology (hematology, clinical chemistry, coagulation tests, and urinalysis), and blood immunophenotyping. Complete necropsies were performed on all animals, gross abnormalities were recorded, and selected tissues were preserved for complete microscopic evaluation. No clinical findings, weight changes, ophthalmologic findings, electrocardiographic effects, blood pressure changes, or clinical pathology findings were associated with ACI-24.060 administration. Mild to moderate, reversible erythema or edema at the injection site was occasionally observed in individual animals in either the control or ACI24.060-treated groups. A single 1712 μg dose of ACI-24.060 did not affect the absolute or relative numbers of helper and cytotoxic T cells, NK cells, activated NK cells, B cells, or monocytes in peripheral blood.

[0119] No findings related to ACI-24.060 were observed at terminal or recovery sacrifice. The 1712 μg ACI-24.060 vaccine dose was well tolerated locally and systemically. No ACI-24.060-related findings were observed at the doses evaluated in this study, and ACI-24.060 was therefore deemed safe and well tolerated at the 1712 μg dose. These results demonstrate the safety and tolerability of chronic administration of ACI-24.060 in cynomolgus monkeys.

[0120] 3.3 Immunogenicity testing in serum: Immunogenicity, i.e., the level of Aβ-specific antibodies produced after vaccination, was assessed using serum samples collected before immunization and 1 and 3 weeks after each immunization (days 8, 22, 36, 50, 64, 78, 92, 106, 120, 134, 148, 162, and 176 for all animals and days 190, 204, and 211 for convalescent animals). Anti-Abeta 1-42 IgG antibody titers were measured for samples collected at each time point using a validated enzyme-linked immunosorbent assay (ELISA). Briefly, Abeta 1-42 peptide film was immobilized on a 96-well microtiter plate at 2-8°C for 12 or 72 hours. After washing and blocking, the plate was incubated with the sample at 37°C for 1 hour to allow binding of anti-Abeta 1-42 IgG antibodies present in the serum. After incubation, the plate was washed to remove non-reactive serum components. Antibody / antigen complexes were detected with a horseradish peroxidase-conjugated anti-human IgG secondary antibody. 3,3',5,5'-tetramethylbenzidine (TMB) substrate was added to the plate wells, and the reaction was stopped with H2SO4. Absorbance was measured at 450 nm and 630 nm using a spectrophotometer. The absorbance at 450 nm was corrected by the absorbance at 630 nm (A450-A630), and the corrected absorbance is proportional to the amount of anti-Abeta 1-42 IgG antibody in the sample. The antibody concentration in the sample was calculated from a standard curve fitted using a four-parameter logistic (4PL) plot.

[0121] Anti-Abeta 1-42 IgM antibody titers were analyzed by ELISA using a qualified method in samples collected before vaccination, 1 week after each immunization, and at a single time point for convalescent animals. Briefly, Aβ 1-42 peptide films were immobilized on 96-well microtiter plates and incubated at 2–8°C for 12 or 72 hours. After washing and blocking, the plates were incubated with the samples for 1 hour at 37°C to allow binding of anti-Abeta 1-42 IgM antibodies present in the serum. After incubation, the plates were washed to remove nonreactive serum components. Antibody / antigen complexes were detected via a secondary anti-human IgM antibody conjugated to horseradish peroxidase. 3,3',5,5'-tetramethylbenzidine (TMB) substrate was added to the plate wells, and the reaction was stopped using H2SO4. Absorbance was measured at 450 and 630 nm using a spectrophotometer. The absorbance at 450 nm was corrected by the absorbance at 630 nm (A450-A630), and the corrected absorbance was proportional to the amount of anti-Abeta 1-42 IgM antibody in the sample. The antibody concentration in the sample was calculated from a standard curve fitted using a four-parameter logistic (4PL) plot.

[0122] Anti-Abeta 1-42 IgG antibody titers in the serum of monkeys immunized with ACI-24EE (group 1, filled circles) or ACI-24.060 (group 2, squares) are shown in Figure 1. Data are presented as geometric means ± 95% confidence intervals (CI), with n = 8 for the placebo group and n = 10 for the ACI-24.060-immunized group. Arrows indicate the days of immunization. **** " indicates a significance level of less than 0.0001. Results showed that animals immunized with ACI-24.060 exhibited strong anti-Abeta 1-42 IgG antibody responses after two immunizations, with significantly higher levels compared to the placebo group. Furthermore, anti-Abeta 1-42 IgG antibody titers increased after each immunization and were maintained for up to 6 weeks after the final immunization, i.e., until the last sample was collected."

[0123] ACI-24.060 induced strong anti-Abeta 1-42 IgG antibody responses after two immunizations and anti-Abeta 1-42 IgM antibody responses after the third immunization. Anti-Abeta 1-42 IgG antibody titers were also detected in the cerebrospinal fluid (CSF) of animals immunized with ACI-24.060.

[0124] 3.4 Immunogenicity testing in cerebrospinal fluid (CSF): In all animals, blood samples were collected by lumbar puncture before vaccination (pre-dose) or from the cisterna magna at necropsy (day 183 for treatment animals and day 211 for recovery animals). Only results from treatment animals are shown. Anti-Abeta 1-42 IgG antibody titers in CSF were analyzed using Meso Scale Discovery (MSD). MSD 96-well small-spot streptavidin microplates were saturated overnight at 4°C with 5% PBS-Blocker A. After washing, the plates were coated with Abeta 1-42 biotinylated peptide film and incubated for 1 hour at 37°C on a shaker at 450 rpm. After washing, samples were added to the plates and incubated for 2 hours at 37°C with shaking to allow binding of anti-Abeta 1-42 IgG antibodies present in the samples. Next, the plates were washed and incubated with sulfo-TAG-labeled anti-human IgG (and IgG1-depleted) antibody for 1 hour at 37°C on a shaker. After washing, the plates were fixed with 1% PBS-formaldehyde for 15 minutes at room temperature with shaking. Antibody concentrations in the samples were calculated from the standard curve using a four-parameter logistic regression method with 1 / y2 weighting using MSD software. Anti-Abeta 1-42 IgG antibody titers in the cerebrospinal fluid of individual monkeys immunized with ACI-24EE (group 1, circles) or ACI-24.060 (group 2, squares) before administration and at necropsy (day 183) are shown in Figure 2. Data are expressed as the geometric mean of individual anti-Abeta 1-42 IgG antibody titers and 95% confidence intervals (AU / mL) (one datum from day 183 in the ACI-24.060 group was excluded due to a %CV > 35%). *indicates a significance level of less than 0.05. As shown in Figure 3, the anti-Abeta 1-42 IgG antibody titers detected in the cerebrospinal fluid of animals after immunization with ACI-24.060 were significantly higher than those before administration, despite large intragroup variability. No anti-Abeta 1-42 IgG antibody titers were observed in the placebo group.

[0125] 3.5 Tissue cross-reactivity To evaluate the potential cross-reactivity of ACI-24.060-immunized cynomolgus monkey serum with human frozen tissues and blood smears from three unrelated donors, a human tissue cross-reactivity (TCR) test was performed using immunohistochemistry (IHC). Brain sections from a human Alzheimer's disease patient served as a positive control. The frozen sections were dried and fixed in zinc formalin. After washing, endogenous peroxidase activity was blocked with a methanol solution containing 3% H2O2. The sections were then washed and incubated in reaction buffer. The slides were uploaded to a Discovery XT2 system for semi-automated IHC staining. The sections were incubated with serum at 37°C for 1 hour, followed by incubation with an anti-monkey-specific secondary antibody. Detection was performed using the OmniMap kit (Ventana) according to the manufacturer's recommendations. Frozen tissue, organ, or blood smears (Table 4) from three unrelated donors were used.

[0126] [Table 4]

[0127] Pooled serum from monkeys (day 92) immunized four times with ACI-24.060 at a dose of 1083 μg / mL was tested. Pooled serum from non-immunized monkeys (before administration) was used as a background level control. The immunized monkey serum specifically labeled Aβ plaques in brain sections from AD patients, but no labeling was observed when sections were incubated with pre-vaccination (pre-administration) monkey serum (Fig. 3a: pre-administration monkey serum pool, Fig. 3b: day 92 monkey serum pool). No off-target cross-reactivity was observed in over 30 frozen human tissues, demonstrating selectivity for Aβ.

[0128] Comparison of antibody titers against pyroglutamate Aβ produced in NHPs by 3.6ACI-24.060 with those of the clinically validated monoclonal antibody donanemab Antibody titers against pyroglutamate Aβ produced after vaccination were evaluated using six NHP serum samples collected on day 176 (3 weeks after the seventh immunization) and the monoclonal antibody donanemab (Thermo Fisher).

[0129] Anti-pyroglutamic acid Abeta 3-42 IgG antibody titers were measured by enzyme-linked immunosorbent assay (ELISA). Briefly, pyroglutamic acid Abeta 3-42 peptide film was immobilized on a 96-well plate and incubated overnight at 2–8°C. After washing and blocking, the plate was incubated with serially diluted serum samples or donanemab for 2 hours at 37°C to allow binding of anti-pyroglutamic acid Abeta 3-42 IgG antibodies present in the samples. After incubation, the plate was washed to remove non-reactive components. Antibody / antigen complexes were detected using a horseradish peroxidase-conjugated anti-human IgG secondary antibody. After a final wash, the plate was incubated with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) substrate solution for 1 hour. Absorbance (optical density, OD) was measured at 450 nm. Anti-pyroglutamate Abeta 3-42 antibody concentrations in NHP serum were back-calculated using an unweighted 4-parameter logistic regression (4PL) model with BioTek Gen5 software (Agilent, version 3.12) against donanemab, and a calibration curve was constructed. Results are presented in μg / mL, along with the mean back-calculated concentrations.

[0130] The OD values ​​of the anti-pyroglutamate Abeta 3-42 IgG ELISA are shown in Figure 4. Six NHP sera collected after seven injections of ACI-24.060 (day 176) were tested in parallel with donanemab. The initial 100-fold dilution or eight 2-fold dilutions from 0.25 μg / mL of serum (upper x-axis) or donanemab (lower x-axis) were plotted against the OD values ​​shown on the y-axis.

[0131] The binding activity of ACI-24.060 vaccine-induced antibodies to pyroglutamate-Abeta 3-42 in NHPs was in the donanemab concentration range of 11–48 μg / mL, which was associated with Aβ plaque clearance in human AD patients (Gueorguieva, I. et al. 2023).

[0132] Comparison of antibody titers against Aβ oligomers produced by ACI-24.060 with those of the clinically validated monoclonal antibody lecanemab in 3.7NHPs Assessment of antibody titers against Aβ1-42 oligomers produced after vaccination was performed using serum samples from six NHPs collected on day 176 (3 weeks after the seventh immunization) and the monoclonal antibody lecanemab (Source: MedChemExpress).

[0133] Anti-Abeta 1-42 oligomer IgG antibody titers were measured using MesoScale Discovery (MSD). MSD 96-well small-spot standard plates were coated with Aβ 1-42 oligomers and incubated overnight at 2–8°C. After washing and blocking, serially diluted serum samples and lecanemab were added to the plates and incubated with shaking at 37°C for 2 hours to allow binding of anti-Abeta 1-42 oligomer IgG antibodies present in the samples. After incubation, the plates were washed to remove non-reactive components and then incubated with sulfo-TAG-labeled anti-human IgG antibodies (containing IgG1 depletion antibodies) on a shaker for 1 hour at 37°C. After a final wash, 2x MSD read buffer was added, and the plates were immediately read on a MesoScale instrument. The luminescence intensity (expressed as ECL value) measured by the MSD reader is proportional to the amount of anti-Abeta 1-42 oligomer IgG present in the sample. Anti-Abeta 1-42 oligomeric antibody concentrations in NHP serum were back-calculated against a standard curve for lecanemab using four-parameter logistic regression with 1 / y2 weighting using MSD software. Results were expressed in μg / mL and as the mean back-calculated concentration.

[0134] The resulting ECL values ​​for anti-Abeta 1-42 oligomeric IgG MSD are shown in Figure 5. Six NHP sera collected after seven injections of ACI-24.060 (day 176) were tested in parallel with lecanemab. Eight 2-fold dilutions from the initial 800-fold dilution or 0.03 μg / mL of serum (upper x-axis) or lecanemab (lower x-axis), respectively, were plotted against the ECL values ​​shown on the y-axis.

[0135] The binding activity of ACI-24.060 vaccine-induced antibodies against Aβ1-42 oligomers in NHPs ranged from 18 to 26 μg / mL per mL of lecanemab. Furthermore, using a modified protocol from Soderberg et al. (2022), we found that ACI-24.060-induced antibodies in NHPs recognized Aβ oligomers more than 1,000-fold more strongly than monomers. This indicates that the specificity for pathological oligomeric Aβ is similar to that previously demonstrated with lecanemab. [Example]

[0136] Example 4: Early prediction of ACI-24.060 amyloid PET decline based on NHP data Quantitative clinical pharmacology models have been developed to describe the amyloid reduction induced by Aβ-targeting mAbs, such as donanemab. Based on patient-level data from the TRAILBLAZER-ALZ trial, Gueorguieva, I. et al. (2023) reported a population pharmacokinetic (PK) model for donanemab that coupled a pharmacodynamic (PD) model for amyloid plaque reduction and ARIA-E (amyloid-related imaging abnormality with edema or exudate) development. The amyloid-reducing PD model is an indirect response model that models amyloid plaque burden (measured by amyloid PET) as a plaque compartment with specific synthesis and degradation rates. The treatment effect of serum donanemab on amyloid PET was modeled as an increase in plaque degradation rate. According to Gueorguieva, I. et al. (2023), serum donanemab concentrations above 4.43 ug / mL were associated with a reduction in amyloid plaques, and "within the dose range studied, higher exposures had no further effect on the amount of amyloid cleared."

[0137] As shown in Example 3.7 above, immunization of NHPs with ACI-24.060 generated IgG that bound and recognized pyroglucomitrogenic Aβ with activity comparable to that achieved with donanemab at concentrations of 11–48 μg / mL. This concentration range is comparable to the estimated minimum serum exposure (Cmin) and mean serum exposure (Cavg) of 8 μg / mL and 40 μg / mL, respectively, achieved in the TRAILBLAZER-ALZ study during the first 3 months of treatment (Table 5). It also exceeds the reported threshold serum concentration of 4.43 μg / mL for donanemab to reduce amyloid PET.

[0138] [Table 5]

[0139] Maximum (Cmax), minimum (Cmin), and mean (Cavg) estimated serum exposures of donanemab obtained from Figure 1 in Gueorguieva, I. et al. (2023). Exposures obtained during the first 3 months of treatment (700 mg IV Q4W) are summarized in the second row, and exposures obtained during the subsequent treatment period (1400 mg IV Q4W) are summarized in the third row.

[0140] These results suggest that ACI-24.060 may reduce amyloid plaques in human AD patients.

[0141] Reference list TIFF2026503655000007.tif241164 TIFF2026503655000008.tif242164 TIFF2026503655000009.tif59164

[0142] 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 incorporated by reference in their entirety for all purposes related to the present invention.

[0143] The present invention is not limited in scope by the specific embodiments described herein. Indeed, various modifications of the present invention in addition to those described herein will become apparent to those skilled in the art from the foregoing description and accompanying drawings. Such modifications are intended to fall within the scope of the appended claims. Moreover, all aspects and embodiments of the present invention described herein are construed as broadly applicable and combinable with any other consistent embodiments, including those appropriately cited (including alone) from other aspects of the present invention.

Claims

1. 1. A liposome vaccine composition for use in inducing an anti-Aβ immune response in a human subject without inducing serious adverse events, comprising: a. A β-amyloid (Aβ)-derived peptide antigen presented on the surface of a liposome, the β-amyloid (Aβ)-derived peptide antigen comprising, consisting essentially of, or consisting of amino acids 1-15 of Aβ; b. a peptide containing a universal T cell epitope, and c. Adjuvants containing monophosphoryl lipid A (MPLA) wherein the beta amyloid (Aβ)-derived peptide antigen is administered in an amount of 300 to 2000 μg.

2. 2. The liposomal vaccine composition for use according to claim 1, wherein the beta amyloid (Aβ) derived peptide antigen is administered in an amount of 300 to 1600 μg, 300 to 1000 μg, or 300 to 900 μg.

3. The liposomal vaccine composition for use according to claim 1 or 2, wherein the peptide containing the universal T cell epitope is at least partially encapsulated in the liposome.

4. The liposome vaccine composition for use according to any one of claims 1 to 3, wherein the peptide comprising a universal T cell epitope comprises an amino acid sequence selected from the group consisting of SEQ ID NO:8, SEQ ID NO:9, SEQ ID NO:10, SEQ ID NO:11, and SEQ ID NO:12, or an analog thereof.

5. 5. The liposomal vaccine composition for use according to any one of claims 1 to 4, wherein the peptides comprising universal T-cell epitopes comprise at least two universal T-cell epitopes, each having an amino acid sequence selected from the group consisting of SEQ ID NO:8, SEQ ID NO:9, SEQ ID NO:10, SEQ ID NO:11 or SEQ ID NO:12, said universal T-cell epitopes being linked by one or more linkers, said one or more linkers comprising, consisting essentially of or consisting of the amino acids VVR, TVGLR, KVSVR, PMGAP or PMGLP, preferably VVR.

6. 6. The liposomal vaccine composition for use according to any one of claims 1 to 5, wherein the peptide comprising a universal T-cell epitope comprises, consists essentially of, or consists of an amino acid sequence selected from the group consisting of SEQ ID NO:5 (SAT44), SEQ ID NO:6 (SAT47), SEQ ID NO:7 (SAT58), SEQ ID NO:3 (SAT42), and SEQ ID NO:4 (SAT43), or an analog thereof.

7. 7. The liposomal vaccine composition for use according to any one of claims 1 to 6, wherein the peptide comprising the universal T-cell epitope comprises, consists essentially of, or consists of the amino acid sequence of SEQ ID NO: 7 (SAT58), or an analog thereof.

8. The liposomal vaccine composition for use according to any one of claims 1 to 7, wherein the beta amyloid (Aβ) derived peptide antigen is administered in an amount of 300 μg.

9. The liposomal vaccine composition for use according to claim 8, wherein the peptide containing the universal T cell epitope is administered in an amount of 90 to 120 μg.

10. The liposomal vaccine composition for use according to claim 8 or 9, wherein MPLA is administered in an amount of 65 to 90 μg.

11. The liposome vaccine composition for use according to any one of claims 8 to 10, wherein the β-amyloid (Aβ)-derived peptide antigen is administered in an amount of 300 μg, the peptide containing a universal T-cell epitope is administered in an amount of 90 to 120 μg, and the MPLA adjuvant is administered in an amount of 65 to 90 μg.

12. The liposomal vaccine composition for use according to any one of claims 1 to 7, wherein the β-amyloid (Aβ) derived peptide antigen is administered in an amount of 900 μg.

13. The liposomal vaccine composition for use according to claim 12, wherein the peptide containing the universal T cell epitope is administered in an amount of 270 to 360 μg.

14. The liposomal vaccine composition for use according to claim 12 or 13, wherein MPLA is administered in an amount of 200 to 270 μg.

15. The liposome vaccine composition for use according to any one of claims 12 to 14, wherein the beta amyloid (Aβ)-derived peptide antigen is administered in an amount of 900 μg, the peptide comprising a universal T cell epitope is administered in an amount of 270 to 360 μg, and MPLA is administered in an amount of 200 to 270 μg.

16. The liposomal vaccine composition for use according to any one of claims 1 to 7, wherein the beta amyloid (Aβ) derived peptide antigen is administered in an amount of 1600 μg.

17. The liposomal vaccine composition for use according to claim 16, wherein the peptide containing the universal T cell epitope is administered in an amount of 470 to 650 μg.

18. The liposomal vaccine composition for use according to claim 16 or 17, wherein MPLA is administered in an amount of 360 to 480 μg.

19. The liposome vaccine composition for use according to any one of claims 16 to 18, wherein the beta amyloid (Aβ)-derived peptide antigen is administered in an amount of 1600 μg, the peptide containing a universal T cell epitope is administered in an amount of 470 to 650 μg, and MPLA is administered in an amount of 360 to 480 μg.

20. The liposomal vaccine composition for use according to any one of claims 1 to 19, wherein the beta amyloid (Aβ) derived peptide antigen is lipidated.

21. The liposomal vaccine composition for use according to any one of claims 1 to 20, wherein the beta amyloid (Aβ) derived peptide antigen is tetrapalmitoylated.

22. A liposomal vaccine composition for use according to any one of claims 1 to 21, wherein the adjuvant forms part of the outer layer of the liposome, optionally at least part of the adjuvant being displayed on the surface of the liposome.

23. The liposomal vaccine composition for use according to any one of claims 1 to 22, wherein the monophosphoryl lipid A (MPLA) comprises synthetic monophosphoryl lipid A (MPLA).

24. 24. The liposomal vaccine composition for use according to any one of claims 1 to 23, wherein the monophosphoryl lipid A (MPLA) comprises monophosphoryl hexaacyl lipid A, 3-deacyl (synthetic) (3D-(6-acyl) PHAD®) and / or phosphorylated hexaacyl disaccharide (PHAD®).

25. The liposomal vaccine composition for use according to any one of claims 1 to 24, wherein the liposome comprises a phospholipid.

26. The liposomal vaccine composition for use according to any one of claims 1 to 25, wherein the phospholipids comprise dimylcitoylphosphatidylcholine (DMPC) and dimylcitoylphosphatidylglycerol (DMPG).

27. The liposomal vaccine composition for use according to any one of claims 1 to 26, wherein the liposomes contain cholesterol.

28. The liposomal vaccine composition for use according to claim 27, wherein the molar ratio of dimylcitoylphosphatidylcholine (DMPC): dimylcitoylphosphatidylglycerol (DMPG): cholesterol is 9:1:

7.

29. The liposome vaccine composition for use according to claim 28, wherein the molar ratio of dimylcitoylphosphatidylcholine (DMPC): dimylcitoylphosphatidylglycerol (DMPG): cholesterol: MPLA is 9:1:7:0.

05.

30. The liposomal vaccine composition for use according to any one of claims 1 to 29, which is administered by injection.

31. The liposomal vaccine composition for use according to any one of claims 1 to 30, which is administered intramuscularly or subcutaneously.

32. The liposomal vaccine composition for use according to claim 31, which is administered intramuscularly.

33. The liposomal vaccine composition for use according to claim 32, which is administered subcutaneously.

34. The liposomal vaccine composition for use according to any one of claims 1 to 33, wherein the liposomal vaccine composition is administered a first time and a second time 1 to 4 weeks later.

35. The liposomal vaccine composition for use according to any one of claims 1 to 33, wherein the liposomal vaccine composition is administered every 4 to 12 weeks for a period of at least 48 weeks or at least 74 weeks.

36. The liposome vaccine composition for use according to any one of claims 1 to 33, wherein the liposome vaccine composition is administered a first time and a second time 2 to 6 weeks later, preferably the second administration is 4 weeks after the first administration.

37. The liposomal vaccine composition for use according to any one of claims 1 to 36, wherein the induced anti-Aβ immune response is obtained after two administrations of the liposomal vaccine.

38. The liposomal vaccine composition for use according to any one of claims 34 to 37, wherein the liposomal vaccine composition is administered a third time 6 to 10 weeks after the second administration of the vaccine composition, preferably the third administration is 8 weeks after the second administration.

39. The liposomal vaccine composition for use according to any one of claims 34 to 38, further comprising a booster administration at a subsequent time point.

40. The liposomal vaccine composition for use according to any one of claims 1 to 39, wherein administration of the liposomal vaccine composition results in a reduction in the amount of Aβ-associated plaques in the brain of a subject.

41. The liposomal vaccine composition for use according to any one of claims 1 to 40, wherein the induced anti-Aβ immune response is for the treatment, prevention, induction of a protective immune response against, or alleviation of symptoms associated with an amyloid-β-related disease or condition in a human subject.

42. 42. The liposomal vaccine composition for use according to claim 41, wherein the amyloid beta-related disease or condition is selected from Alzheimer's disease, mild cognitive impairment (MCI), Down's syndrome (DS), Down's syndrome-associated Alzheimer's disease, cardiac amyloidosis, cerebral amyloid angiopathy (CAA), multiple sclerosis, Parkinson's disease, dementia with Lewy bodies, ALS (amyotrophic lateral sclerosis), adult-onset diabetes mellitus, inclusion body myositis (IBM), ocular amyloidosis, glaucoma, macular degeneration, lattice dystrophy, and optic neuritis.

43. The liposomal vaccine composition for use according to claim 42, wherein the amyloid-β related disease or condition is Alzheimer's disease.

44. The liposomal vaccine composition for use according to claim 43, wherein the Alzheimer's disease is early Alzheimer's disease.

45. The liposomal vaccine composition for use according to claim 44, wherein the early stage of Alzheimer's disease includes prodromal Alzheimer's disease, mild cognitive impairment due to Alzheimer's disease, and mild Alzheimer's disease.

46. The liposomal vaccine composition for use according to claim 43, wherein the Alzheimer's disease is prodromal Alzheimer's disease.

47. The liposome vaccine composition for use according to claim 43, wherein the Alzheimer's disease is mild Alzheimer's disease.

48. The liposome vaccine composition for use according to claim 43, wherein the Alzheimer's disease is mild to moderate Alzheimer's disease.

49. The liposome vaccine composition for use according to claim 43, wherein the Alzheimer's disease is moderate Alzheimer's disease.

50. The liposome vaccine composition for use according to claim 43, wherein the Alzheimer's disease is not severe Alzheimer's disease.

51. The liposomal vaccine composition for use according to claim 42, wherein the amyloid-β related disease or condition is Down's syndrome.

52. The liposomal vaccine composition for use according to claim 42, wherein the amyloid β-related disease or condition is Down's syndrome-related Alzheimer's disease.

53. 53. The liposomal vaccine composition for use according to any one of claims 1 to 52, wherein the human subject before treatment exhibits cognitive function consistent with a Mini-Mental State Examination (MMSE) score of at least 18, for example 18 to 28, or at least 20, for example 20 to 28.

54. The liposomal vaccine composition for use according to any one of claims 1 to 53, wherein the β-amyloid (Aβ) derived peptide antigen is tetrapalmitoylated Aβ1-15 as set forth in SEQ ID NO:

1.

55. The liposomal vaccine composition for use according to any one of claims 1 to 54, wherein the human subject is receiving at least one additional treatment selected from an acetylcholinesterase inhibitor (ACHEI) and / or memantine.

56. 1. A liposome vaccine composition for use in inducing an anti-Aβ immune response in a human subject without inducing serious adverse events, comprising: a. A β-amyloid (Aβ)-derived peptide antigen displayed on the surface of a liposome, the β-amyloid (Aβ)-derived peptide antigen comprising, consisting essentially of, or consisting of amino acids 1-15 of Aβ, wherein the β-amyloid (Aβ)-derived peptide antigen is tetrapalmitoylated Aβ1-15 as set forth in SEQ ID NO: 1; b. A peptide comprising a universal T-cell epitope comprising, consisting of, or consisting essentially of the amino acid sequence of SEQ ID NO: 7 (SAT58), or an analog thereof; and c. An adjuvant comprising monophosphoryl lipid A (MPLA), preferably 3D-(6-acyl)PHAD® wherein the beta amyloid (Aβ) derived peptide antigen is administered in an amount of 300 to 2000 μg, preferably 300 to 1600 μg, preferably 300 μg, 900 μg, or 1600 μg.

57. A liposomal vaccine composition comprising: a. A β-amyloid (Aβ)-derived peptide antigen presented on the surface of a liposome, the 1-15 amino acid peptide antigen comprising, consisting essentially of, or consisting of amino acids 1-15 of Aβ, wherein the β-amyloid (Aβ)-derived peptide antigen is tetrapalmitoylated Aβ1-15 as set forth in SEQ ID NO: 1; b. A peptide comprising a universal T-cell epitope consisting essentially of or consisting of Aβ, comprising the amino acid sequence of SEQ ID NO: 7 (SAT58), or an analog thereof; c. An adjuvant comprising monophosphoryl lipid A (MPLA), preferably 3D-(6-acyl)PHAD®.

58. 58. The liposomal vaccine composition of claim 57, comprising a β-amyloid (Aβ)-derived peptide antigen in an amount of 300 μg, a peptide containing a universal T-cell epitope in an amount of 90 to 120 μg, and an MPLA adjuvant in an amount of 65 to 90 μg.

59. 58. The liposomal vaccine composition of claim 57, comprising a β-amyloid (Aβ)-derived peptide antigen in an amount of 900 μg, a peptide comprising a universal T-cell epitope in an amount of 270-360 μg, and MPLA in an amount of 200-270 μg.

60. 58. The liposomal vaccine composition of claim 57, comprising a beta amyloid (Aβ)-derived peptide antigen in an amount of 1600 μg, a peptide comprising a universal T cell epitope in an amount of 470 to 650 μg, and MPLA in an amount of 360 to 480 μg.

Images