WO1999027956A1

WO1999027956A1 - Tolerance inducing combination of at least two endogenous antigens for treatment of sms, sle, iddm, etc.

Info

Publication number: WO1999027956A1
Application number: PCT/SE1998/002154
Authority: WO
Inventors: Anders Essen-Möller
Original assignee: Diamyd Therapeutics Ab
Priority date: 1997-11-28
Filing date: 1998-11-27
Publication date: 1999-06-10
Also published as: AU1580399A; SE9704451D0

Abstract

A new method for the treatment of autoimmune diseases in human patients is disclosed, said method involving the re-balancing of the patient's immune response using specific, functional adjuvant/s and the administration of at least two antigens associated with the disease to be treated. Accordingly, a new composition is disclosed, said composition comprising at least antigens together with a functional adjuvant, capable of re-balancing the immune response in relation to the response, typical for the disease to be treated.

Description

TOLERANCE INDUCING COMBINAΗON OF AT LEAST TWO ENDOGENOUS ANTIGENS FOR TREATMENT OF SMS, SLE, IDDM, ETC.

The present invention concerns a method and compositions for the induction of tolerance against an endogenous antigen in the treatment of autoimmune diseases and in particular a method and compositions for the induction of a specific immune response, chosen depending on the mode of action of the autoimmune disease to be treated. Background of the invention

Novel autoantibody assays permit rapid and reliable identification of individuals with an autoreactivity. As now evident, in an autoimmune disease such as insulin-dependent diabetes it is possible to use autoantibodies to GAD65 (glutamate decarboxylase) as a means to predict the clinical onset of the disease. The destruction of the organ (i.e. the insulin- producing cells in the islets of Langerhans) is virtually complete at the time of clinical diagnosis. In addition to the autoantibodies, all cells of the immune system including macrophages, T helper cells and T cytotoxic cells may be detected at the site of the lesion. Autoimmune diseases are often associated with complete loss of function such as the production of insulin. All insulin producing cells are destroyed. This destruction is chronic and the immune system maintains its memory towards beta cell self-reactivity since pancreas and islet transplantation is associated with reappearance of GAD65 antibodies in patients who were GAD65 antibody negative at the time of transplantation.

The complete immunological destruction of the target cells results in a deficiency of a cellular product (such as insulin) or loss of function. The treatment of an autoimmune disease is therefore almost always a substitution therapy. The loss of endogenous insulin production is replaced by exogenous replacement therapy with insulin. This type of therapy has sustained the life of millions of diabetic patients since the discovery of insulin in 1921.

There is currently no remedy for organ-specific autoimmune diseases. Current treatment is conservative and the symptoms are often treated with a large variety of immune suppressive agents. In disease such as insulin-dependent diabetes, thyroiditis and Addison's disease the treatment is replacement of the lost hormone. Immunotherapy may alleviate the symptoms but the patients are never cured from their condition. Insulin therapy is for life and the life sustaining ability of insulin is incomplete. In fact, the disease in fact has a 500% overmortality due to the development of long term complications, These complications affect vital organs and functions and include nephropathy (almost 30% of all kidney transplants are due to diabetic kidney disease), retinopathy (diabetes is the most common cause of acquired blindness) neuropathy (foot ulcers developed due to reduced sensations) and macrovascular disease (increased frequency of myocardial infarctions; the most common cause of amputations is diabetes). A method to halt the immunological activities against autoantigens would therefore be of immense importance to the treatment of organ-specific autoimmunity.

The administration of antigens in order to elicit an immune response is a well known technique, successfully practised in the form of vaccination. During the second half of our century, numerous diseases have been practically eradicated in the western world, thanks to consequently performed vaccination programs encompassing the whole population.

It has more recently been shown, that specific antigens have a central role in serious autoimmune diseases, such as diabetes, and that these antigens can be administered to a patient in order not only to induce immunity but also to induce tolerance to the respective antigens. Insulin, an endogenous antigen associated with diabetes, has been used in this manner. Also the protein known as GAD65 has b>sen suggested for use in order to induce tolerance. Alternatively, genetic information governing the expression of the desired antigen can be introduced, for example incorporated in a host-organism. These practices are however associated with the risk of aggravating the condition. The administration of cDNA in particular has shown to elicit a cell mediated response, that is a T-cell response.

Consequently, the prior art methods and substances for inducing tolerance to endogenous antigens are thus subject to a severe drawback in that the immune response cannot be properly predicted or influenced. The immune system can react to the treatment by either mobilising a cell-mediated or humoral, antibody mediated response. Despite striking immunological advances in the past 20 years, adjuvant use remains largely empiric. Their mechanisms of action in vitro and in vivo are as varied as the immune response itself. In fact, few if any studies have revealed how any adjuvant operates in vivo. There is an urgent need for novel methods and/or substances making it possible to influence the character of the immune response and thus helping to ensure a positive end-result of the treatment. Further, prior art methods and compositions, involving the administration of single antigens, associated with the autoimmune disease to be treated, are subjected to serious drawbacks. Firstly, studies indicate that not all patients respond to the treatment. Secondly, there is the risk of inducing hypersensitivity to the host's own tissues, producing autoimmune reactions and possibly aggravating the disease to be treated. Summary of the invention

The above problems are solved or alleviated through a novel method and composition according to the attached claims. Through the simultaneous administration of at least two antigens, associated with the disease to be treated, a more balanced immune response can be achieved. The present inventor further discloses, that specific compounds influence the immune response and, in admixture with the antigen to be administered, can act as functional adjuvants, directing the immune response in the desired direction i.e. towards an immune mediated response. The present invention thus makes available a novel method and compositions for inducing tolerance to endogenous antigens. The present invention in particular discloses the simultaneous administration of two or more antigens, associated with the same disease, in admixture with or simultaneously with a functional adjuvant, rebalancing or guiding the immune system towards the humoral antibody producing arm or towards the cell mediated defence arm, depending of the nature of the disease in question.

Description of the invention Vaccination therapy can be summarised as a method of inducing an immune response to an exogenous, pathogenic agent, such as a virus or bacteria. An inactivated form of the pathogenic agent or specific antigens associated with the same, are administered to a patient in order to induce an immune response, thus making the patient's immune system better prepared to encounter the pathogen. In order to amplify the immune response, suitable adjuvants are administered in admixture with the inactivated pathogenic agent.

In the following text, the term "adjuvant" denotes an agent that increases specific immune responses to an antigen. The term "carrier" is used in the following to describe any immunogenic protein bound to a hapten or to a weakly immunogenic antigen. Carriers increase the immune response by providing T-cell help to the hapten or antigen. Further, the term "vehicle" denotes the substrate for the adjuvant, the antigen and/or the antigen-carrier complex. Unlike carriers, vehicles are not themselves immunogenic. Like carriers, most vehicles can alone enhance antigens and are consequently sometimes considered to be another class of adjuvants. The term "adjuvant formulation" means in this context an adjuvant in a suitable vehicle. As antigen is processed by antigen presenting cells (APC:s) and antigen fragments then via MHC class-Ll molecules are presented to T-helper cells, immune reactivity is largely dependent on said MHC-class II molecules which vary from individual to individual. The method of the present invention is therefor to present the individual's immune system with an sufficient amount of various antigen in a form that immune modulates away from the for the autoimmune disorder predominating and harmful defence arm - let it be humoral or cell- mediated. The immunological tolerance induced is caused by re-balancing the immune system through exposure to a panel of antigens together with a disease specific, functional adjuvant. Also, the administration of only one antigen, associated with an autoimmune disease, may cause over-production of antibodies. By the simultaneous administration of at least two antigens, associated with the disease, a more balanced response is achieved. Further, the immunogenic properties of the composition according to the invention may also be influenced, not only by the choice of antigen/s and adjuvant/s but by the ratio between these components. According to one embodiment of the present invention, the at least two antigens are administered in admixture with the functional adjuvant and possible carrier and vehicle, easily chosen by a person skilled in the art. However, the present inventors disclose the possibility of administering the at least two antigens and the functional adjuvant through different routes of administration. It is, for example, conceivable that one antigen is administered orally and one other via injection, either intravenously or intramuscularly. The adjuvant can likewise be administered through different routes, chosen so that the desired immune response balancing effect is achieved. Intra nasal delivery has shown to be highly effective for generating an antibody response and is thus considered as a preferred route of administration, alone or in conjuction with other routes. Examples of suitable adjuvants presently approved by the FDA include aluminium salts, for example alum. In addition to these, several adjuvants are under study and in some cases human trials .are in progress. For example Ouil-A and Ribi Adjuvant System (RAS) have been shown to augment the production of IgGl and IgG2. Also, the Montanide CSA 720 adjuvant has been shown to induce an antibody response, and according to recent studies, does this faster and resulting in higher titres than achieved with alum. Other, recently published studies indicate, that the presentation of IL-12 on alum enchances its immunomodulatory effects and the use of the cytokine as an adjuvant for simultaneously promoting both humoral antibody and type 1 cytokine responses is suggested. Examples of adjuvants, inducing a cell mediated response include, but are not limited to, gliding bacterial adjuvant (GBA) which has shown to induce T cell proliferation in vitro. The choice of adjuvant is, for practical purposes, limited by the regulations currently in force, i.e. FDA regulations. Naturally, a skilled person can choose a suitable adjuvant within the scope of the present invention, among adjuvants presently under development.

Examples of vehicles include mineral oil emulsions (Freund's), vegetable oil emulsions (peanut oil), microspheres, liposomes, antigen phospholipid complexes, nonionic block polymer surfactants, squalene and squalane.

Examples of carriers include bacterial toxoids, fatty acids, bentonite, cholera toxin, KLH (keyhole limpet hemocyanin), living vectors (attenuated salmonella, adenovirus, polio vaccine virus, etc). When the purpose is to induce tolerance, an immune response is highly unwanted. On the contrary, it is the overly active immune system that is the cause of the disease. According to the present invention, the mode of administration and the adjuvants, administered in admixture with or simultaneously with the antigen/antigens, are chosen so that an cell mediated immune response is avoided or minimised and in particular, the adjuvants are chosen so, that a antibody mediated response is achieved. Consequently, the present invention discloses a method for the treatment of autoimmune diseases, characterized in that two or more antigens, associated with the disease in question, are administered to a patient in doses, inducing tolerance, in admixture with or simultaneously with an adjuvant, capable of re-balancing the immune response away from that response associated with the disease to be treated, for example causing an antibody mediated immune response in diseases associated with a cell mediated response and vice versa.

According to a preferred embodiment of the invention, alum is used as the antibody response causing adjuvant. Further, according to the present invention, two or more antigens are administered simultaneously. In particular, the present invention discloses the simultaneous administration of insulin and protein GAD65, together with a suitable adjuvant, causing an antibody mediated response. Other antigens of central importance in the development of autoimmune diseases are, in IDDM for example ICA512 (IA2), ICA512B (IA2B), insulin, Hsp60, Hsp65, ICA69, Glima38, Imogen 38, Insulin-Bchain and other autoantigen relevant to insulin dependent diabetes.

Importantly, the nature of the autoimmune disease in question must be considered in choosing the treatment. Stiff man syndrome (SMS) and systemic lupus erythromatosus (SLE) are associated with an antibody mediated immune response, whereas insulin dependent diabetes (IDDM), multiple sclerosis (MS) and rheumatoid arthritis (RA) are associated with a cell-mediated response. In the treatment of these and similar diseases, the adjuvant, vehicle and possible modes of administration are to be chosen so, that the immune response is rebalanced towards a cell-mediated response in the case of SMS and SLE, and towards an antibody mediated response in the case of IDDM, MS and RA, only to mention a few examples.

Suitable modes of administration of the tolerance inducing substance according to the present invention are the following: intravenous, intra muscular or nasal administration. Oral administration can be suitable in cases, where the substance is formulated so that it can pass through the upper gastro-intestinal tract without loosing its biological function or in cases where the active components are expressed in the lower gastro-intestinal tract and where an uptake through the intestinal mucus membrane is possible.

Example A tolerance inducing composition is prepared by mixing protein GAD65 and insulin, respectively in a liquid carrier, preferably pyrogene free water for injections (WFI). An

.antibody response causing adjuvant, preferably alum, is added. The tolerance inducing composition is sterile filtered, homogenized, packaged in glass vials and sealed under sterile conditions. The filled vials are subjected to normal quality control measures, making certain that the end-product complies with pharmacopeic reflations (European Pharmacopeia). The tolerance inducing composition is injected intramuscularly in a patient, subject to tolerance inducing therapy. The patient's antibody ther is monrtor«3d in order to follow the response to the treatment.

Although the invention has been described with r>sgard to its preferred embodiments, which constitute the beΛ mode presently lαiown to the inventors, it should be understood that various changes and modifications as would be obvious to one having the ordinary skill in this art may be made without departing from the scope of the invention which is set forth in the claims appended hereto.

Claims

1. Composition for the treatment of autoimmune diseases by inducing tolerance to endogenous antigens in a human patient, characterized in that said composition contains at least two antigens.

2. Composition for the treatment of autoimmune diseases by inducing tolerance to endogenous antigens in a human patient, characterized in that said composition contains at least two antigens and at least one adjuvant which elicits an humoral, antibody mediated immune response.

3. Composition according to any one of claim 1 - 2, characterized in that the at least two antigens are chosen from the group comprising insulin, GAD65, ICA512 (IA2), ICA512B

(IA2B), Hsp60, Hsp65, ICA69, Qima38, Imogen 38, Insulin-Bchain and other autoantigen relevant to insulin dependent diabetes and any peptide thereof or cDNA-sequence coding for one of said antigens.

4. Composition according to claim 2, characterized in that the antigens are insulin and protein G AD65.

5. Composition according to any one of claim 2 - 4, characterized in that the at least one adjuvant is/are chosen from the group comprising aluminium salts, preferably alum.

6. Method for the treatment of an autoimmune disease in a human patient, characterized in that the immune response of said patient is directed towards either a cell- mediated response or a humoral, antibody mediated response, depending on the nature of the specific autoimmune disease to be treated.

7. Method for the treatment of an autoimmune disease in a human patient by inducing tolerance to endogenous antigens, characterized in that at least two antigens are administered simultaneously to said patient. 8. Method for the treatment of an autoimmune disease in a human patient by inducing tolerance to endogenous antigens, characterized in that at least two antigens are administered to said patient simultaneously with an adjuvant which elicits an antibody mediated response.

9. Method for the treatment of insulin dependent diabetes, characterized in that GAD65 and insulin are administered to the patient in admixture or simultaneously with alum. AMENDED CLAIMS

[received by the International Bureau on 27 April 1999 (27.04.99); original claims 1-9 replaced by amended claims 1-9 (1 page)]

Claims

1. Use of a composition comprising at least two antigens and at least one functional adjuvant, which adjuvant elicits an humoral, .antibody mediated immune response, for the treatment of an immune disease associated with a cell mediated immune response.

2. Use of a composition comprising at least two antigens and at least one functional adjuvant, which adjuvant elicits a cell mediated immune response, for the treatment of an immune disease associated with an humoral, antibody mediated immune response. 3. Use according to claim 1 , characterized in that the disease is one of insulin dependent diabetes mellitus (IDDM), multiple sclerosis (MS) and rheumatoid arthritis (RA).

4. Use according to claim 3, characterized in that the at least two antigens are chosen from the group comprising insulin, GAD65, ICA512 (IA2), ICA512β (IA2β), HspόO, Hsp65, ICA69, Glima38, Imogen 38, Insulin-B chain and the adjuvant is alum.

5. Use according to claim 2, characterized in that the disease in one of stiff man syndrome (SMS) and systemic lupus erythromatosus (SLE).

6. Use according to claim 5, characterized in that the adjuvant is gliding bacterial adjuvant (GBA). 7. Method for re-balancing the immune response in a patient suffering from a disease associated with a cell mediated immune response, characterized in that at least two antigens, associated with the disease in question, are administered to said patient in doses inducing tolerance, simultaneously with an adjuvant, capable of eliciting a humoral, antibody mediated immune response.

8. Method according to claim 7, characterized in that the disease is one of insulin dependent diabetes mellitus (IDDM), multiple sclerosis (MS) and rheumatoid arthritis (RA).

9. Method according to claim 8, characterized in that the at least two antigens are chosen from the group comprising insulin, GAD65, ICA512 (IA2), ICA512β (IA2β), HspόO, Hsp65, ICA69, Glima38, Imogen 38. Insulin-B chain and the adjuvant is alum.