WO2020007937A1

WO2020007937A1 - Use of interleukin-2 for treating systemic sclerosis

Info

Publication number: WO2020007937A1
Application number: PCT/EP2019/067898
Authority: WO
Inventors: David Klatzmann; Roberta LORENZON; Arsène MEKINIAN; Michelle ROSENZWAJG
Original assignee: Iltoo Pharma; Assistance Publique - Hôpitaux De Paris; Sorbonne Universite
Priority date: 2018-07-03
Filing date: 2019-07-03
Publication date: 2020-01-09

Abstract

The invention relates to the use of interleukin-2 in treating systemic sclerosis in a subject, wherein IL-2 is to be administered at a low dose of less than about 3.5 MlU/day.

Description

Use of interleukin 2 for treating systemic sclerosis

The present invention relates to administering low dose interleukin 2 (IL-2) for use in treating systemic sclerosis.

Background of the invention

Systemic sclerosis, also known as“scleroderma”, is a rare and serious immune-mediated rheumatic disease that is characterized by fibrosis of the skin and internal organs and vasculopathy. The early symptoms of the disease are often Raynaud’s phenomenon and gastro-oesophageal reflux in association with specific anti-nuclear antibody (ANA) profile. Clinical manifestations include inflammatory skin disease (puffy and swollen fingers), skin fibrosis, ulcers, calcinosis, telangiectasia, musculoskeletal inflammation, or constitutional manifestations such as fatigue. A subgroup of patients displays organ based manifestations of the disease, which might include lung fibrosis, pulmonary arterial hypertension, renal failure (usually with accelerated phase hypertension and a thrombotic microangiopathy clinical picture), or gastrointestinal complications.

Chronic disease burden and morbidity are significant. Systemic sclerosis has a high mortality, greater than any other rheumatic disease. However no disease-modifying drugs for systemic sclerosis exist. The currently available treatments merely aim at reducing the complications of skin or internal organs (for a review, see Denton and Khanna, The Lancet, 2017, 390:1685- 1699) .

Treatment of skin-associated complications and interstitial lung disease consists in immune- modulating therapies (such as methotrexate, mycophenolate mofetil or cyclophosphamide). Non-steroidal anti-inflammatory drugs and low-dose daily prednisolone may be helpful for musculoskeletal pain in association with intensive physiotherapy or occupational therapy. Patients with a poor prognosis and lung fibrosis can receive intensive immunosuppression with haemopoietic autologous stem-cell transplantation (HSCT).

Endothelin receptor antagonists, epoprostenol analogues, and phosphodiesterase-5 inhibitors may be used for controlling pulmonary arterial hypertension. Use of ACE inhibitors in prevention of renal crisis is highly debated. In addition, rituximab is being proposed as an alternative to cyclophosphamide for the treatment of interstitial lung diseases. Summary of the invention

It is herein provided a method for treating systemic sclerosis in a subject by administration of a low dose of IL-2, namely a dose of at most 3.5 MlU/day.

More specifically the invention provides IL-2 for use in treating systemic sclerosis in a subject, wherein IL-2 is to be administered at a dose of about 1 to about 2MIU/day, wherein the treatment comprises at least a first course wherein interleukin-2 is administered once per day during at least 2 or 3 consecutive days, preferably during 3 to 7, still preferably during 4 to 5 consecutive days, preferably followed by a maintenance dose after about six days or one week to about 4 weeks.

This dosage has been chosen to effectively expand and activate Tregs without substantially activating Teffs. The consequence is a dramatic increase in the Treg/Teff balance in the subject, without impact on its immunocompetency.

Legend to the Figure:

The Figure shows reduction of the Rodnan’s skin score in a patient with systemic sclerosis, treated with low dose IL-2 as described in the Example.

Detailed description of the invention:

Definitions

The“subject” or“patient” to be treated may be any mammal, preferably a human being. The human subject may be a child, an adult or an elder. Systemic sclerosis is more frequent in women, but any gender is encompassed. Typically the patient may especially be an adult who is more than 30 or 40 years old. The patients include patients affected with“Primary Systemic sclerosis”, with no other rheumatic disease, patients affected by “Sharp’s syndrome” (Mixed connective tissue disease (MCTD) disease with features of three diseases: lupus, scleroderma and polymyositis), and patients with “Reynolds syndrome” an association of Systemic sclerosis and primary biliary cirrhosis.

The term“treating” or“treatment” means any improvement in the disease. It includes alleviating at least one symptom, or reducing the severity or the development of the disease. In particular it includes reducing the risk, occurrence or severity of acute episodes (flares). The term“treating” or“treatment” encompasses reducing the progression of the disease. In particular the invention encompasses preventing or slowing down the progression of systemic sclerosis. The term“treating” or“treatment” further encompasses prophylactic treatment, by reducing the risk or delaying the onset of the disease, especially in a subject who is asymptomatic but has been diagnosed as being“at risk”.

“Regulatory T cells” or“Tregs” are T lymphocytes having immunosuppressive activity. Natural Tregs are characterized as CD4+CD25+Foxp3+ cells. Tregs play a major role in the control of inflammatory diseases, although their mode of action in such disease is not well understood. In fact, in most inflammatory diseases, Treg depletion exacerbates disease while Treg addition decreases it. Most Tregs are CD4+ cells, although there also exists a rare population of CD8+ Foxp3+ T lymphocytes with a suppressive activity.

Within the context of this application, "effector T cells" (or“Teff”) designates conventional T lymphocytes other than Tregs (sometimes also referred to as Tconv in the literature), which express one or more T cell receptor (TCR) and perform effector functions (e.g., cytotoxic activity, cytokine secretion, anti-self recognition, etc). Major populations of human Teff according to this invention include CD4+ T helper lymphocytes (e.g., ThO, Thl, Thl7) and CD4+ or CD8+ cytotoxic T lymphocytes, and they can be specific for self or non-self antigens.

Systemic sclerosis

The present invention relates to administering interleukin 2 (IL-2) for use in treating systemic sclerosis, including diffuse cutaneous systemic sclerosis or limited cutaneous systemic sclerosis. Indeed cases of systemic sclerosis can generally be classified into one of two major disease subsets based on the extent of skin involvement: those with proximal involvement are classified as diffuse cutaneous systemic sclerosis, whereas those with restricted involvement affecting the limbs distal to the elbows or knees, with or without face and neck involvement, are classified as limited cutaneous systemic sclerosis. These skin-based subsets define the disease dichotomously and have other distinguishing clinical associations, as well as specific serum autoantibody profiles. More specifically, the present invention relates to alleviating, delaying, slowing down or preventing development of articular and extra-articular symptoms, more particularly skin involvement, vascular manifestations (Raynaud’s phenomenon), organ failure, lung fibrosis, gastrointestinal manifestations, cardiac disease, pulmonary hypertension, and fatigue in patients with systemic sclerosis.

In a particular aspect, it is provided a method for treating articular symptoms of systemic sclerosis (such as arthralgia, puffy fingers or morning stiffness) in a patient in need thereof. In a particular embodiment the present invention aims at preventing or alleviating articular symptoms in patients with systemic sclerosis, such as arthralgia, puffy fingers or morning stiffness.

In another embodiment, the method provides preventing or alleviating skin involvement of systemic sclerosis, including skin thickening or hardening, which can be measured by a modified Rodnan skin score, as described e.g. in Khanna et al, Journal of Scleroderma and Related Disorders 2017“Standardizaton of the modifed Rodnan skin score for use in clinical trials of systemic sclerosis”. The modified Rodnan skin score (MRSS) is a standard outcome measure for skin disease in systemic sclerosis and calculated by summation of skin thickness in 17 different body sites (total score = 51).

Importantly, measurement of skin thickening may also be used as a surrogate for disease activity.

Interleukin 2 (IL-2)

As used herein, Interleukin-2 (IL-2) encompasses mammal wild type Interleukin-2, and variants thereof. Preferably, IL-2 is a human IL-2, or a variant thereof.

Active variants of IL-2 have been disclosed in the literature. Variants of the native IL-2 can be fragments, analogues, and derivatives thereof. By "fragment" is intended a polypeptide comprising only a part of the polypeptide sequence. An "analogue" designates a polypeptide comprising the native polypeptide sequence with one or more amino acid substitutions, insertions, or deletions. Muteins and pseudopeptides are specific examples of analogues. "Derivatives" include any modified native IL-2 polypeptide or fragment or analogue thereof, such as glycosylated, phosphorylated, fused to another polypeptide or molecule, polymerized, etc., or through chemical or enzymatic modification or addition to improve the properties of IL-2 (e.g., stability, specificity, etc.). The IL-2 moiety of active variants (including fragments, analogues, or derivatives) generally has at least 75%, preferably at least 80%, 85%, more preferably at least 90% or at least 95% amino acid sequence identity to the amino acid sequence of the reference IL-2 polypeptide, for instance mature wild type human IL-2.

Methods for determining whether a variant IL-2 polypeptide is active are available in the art. An active variant is defined as a variant that shows an ability to stimulate Tregs, including variants with an improved ability, or a similar ability, or even a reduced ability to stimulate Tregs when compared to wild-type IL-2 or aldesleukin (as defined below), to the extent it does not stimulate Teffs more than it stimulates Tregs at the dosage herein defined. Methods for testing whether a candidate molecule stimulate T cells, and Tregs in particular, are well- known. Variants may be tested for their ability to stimulate effector T cells (such as CD8+ T cells and NK cells) or CD4+Foxp3+ Tregs.

A typical in vitro method for determining the ability of a candidate variant to preferentially stimulate Treg cells is described hereafter. Total PBMC are activated (e.g. at 4x10⁶ cells per well) with anti-CD3 antibody (e.g. at 100 ng/ml), and cultured. On day 3 of culture, cells are typically washed and rested in fresh media for 3 days. Cells are then washed and contacted with IL-2 variants (e.g. at either 10 nM or 100 pM). About three days later, cells are counted and analyzed by flow cytometry.

Said active variants induce signaling events that preferentially induce survival, proliferation, activation and/or function of Treg cells. In certain embodiments, the IL-2 variant retains the capacity to stimulate, in Treg cells, STAT5 phosphorylation and/or phosphorylation of one or more of signaling molecules downstream of the IL-2R, e.g., p38, ERK, SYK and LCK. In other embodiments, the IL-2 variant retains the capacity to stimulate, in Treg cells, transcription or protein expression of genes or proteins, such as FOXP3 or IL-10, that are important for Treg cell survival, proliferation, activation and/or function. In other embodiments, the IL-2 variant exhibits a reduced capacity to stimulate endocytosis of IL- 2/IL-2R complexes on the surface of CD25+ T cells. In other embodiments, the IL-2 variant demonstrates inefficient, reduced, or absence of stimulation of PI3 -kinase signaling, such as inefficient, reduced or absent phosphorylation of AKT and/or mTOR (mammalian target of rapamycin). In yet other embodiments, the IL-2 variant retains the ability of wild type IL-2 to stimulate STAT5 phosphorylation and/or phosphorylation of one or more of signaling molecules downstream of the IL-2R in Treg cells, yet demonstrates inefficient, reduced, or absent phosphorylation of STAT5, AKT and/or mTOR or other signaling molecules downstream of the IL-2R in FOXP3- CD4+ or CD8+ T cells or NK cells. In other embodiments, the IL-2 variant is inefficient or incapable of stimulating survival, growth, activation and/or function of FOXP3- CD4+ or CD8+ T cells or NK cells.

In all cases, these variants have the capacity to stimulate cell lines such as CTLL-2 or HT-2 which can be universally used to determined their biological activity.

As used herein, "wild type IL-2" means IL-2, whether native or recombinant, having the 133 normally occurring amino acid sequence of native human IL-2 (SEQ ID NO: 1, which is the IL-2 sequence less the signal peptide, consisting of an additional 20 N-terminal amino acids), whose amino acid sequence is described in Fujita, et. al, PNAS USA, 80,7437-7441 (1983). As used herein, "IL-2 mutein" means a polypeptide in which specific substitutions to the human mature interleukin-2 protein have been made.

Examples of IL-2 variants are disclosed, for instance, in EP109748, EP136489, US4,752,585 ; EP200280, EP118617, WO99/60128, EP2288372, US9,6l6,l05, US9,580,486,

WO2010/085495, WO2016/164937.

For instance, certain mutations may result in a reduced affinity for the signaling chains of the IL-2 receptor (IL-2Rp/CD 122 and/or IL-2Ry/CDl32) and/or a reduced capacity to induce a signaling event from one or both subunits of the IL-2 receptor. Other mutations may confer higher affinity for CD25 (IL-2Ra).

Particular examples of useful variants include IL-2 muteins which show at least one amino acid substitution at position D20, N30, Y31, K35, V69, Q74, N88, V91, or Q126, numbered in accordance with wild type IL-2, meaning that the chosen amino acid is identified with reference to the position at which that amino acid normally occurs in the mature sequence of wild type IL-2 of SEQ ID NO:l.

Preferred IL-2 muteins comprise at least one substitution at position D20H, D20I, D20Y, N30S, Y31H, K35R, V69AP, Q74, N88R, N88D, N88G, N88I, V91K, or Q126L

We prefer conservative modifications and substitutions at other positions of IL-2 (i. e., those that have a minimal effect on the secondary or tertiary structure of the mutein).

Such conservative substitutions include those described by Dayhoff in The Atlas of Protein Sequence and Structure 5 (1978), and by Argos in EMBO J., 8: 779-785 (1989).

For example, amino acids belonging to one of the following groups represent conservative changes: -ala, pro, gly, gln, asn, ser, thr; -cys, ser, tyr, thr; -val, ile, leu, met, ala, phe; -lys, arg, his; -phe, tyr, trp, his ; and -asp, glu.

Variants with mutations which disrupt the binding to the a subunit of IL-2R are not preferred, as those mutants may have a reduced capacity to stimulate Tregs.

IL-2 can be produced by DNA recombinant technique. The host organism used to express a recombinant DNA encoding IL-2 may be prokaryotic (a bacterium such as E. coli) or eukaryotic (e.g., a yeast, fimgus, plant or mammalian cell). Processes for producing IL-2 have been described e.g., in US4,656,l32; US4,748,234; US4,530,787; or US4,748,234, incorporated therein by reference.

Alternatively, IL-2 can be produced by chemical peptide synthesis. For instance, IL-2 can be produced by the parallel synthesis of shorter peptides that are subsequently assembled to yield the complete sequence of IL-2 with the correct disulfide bridge. A synthesis of Interleukin-2 is illustrated for instance in Asahina et al., Angewandte Chemie International Edition, 2015, Vol.54, Issue 28, 8226-8230, the disclosure of which being incorporated by reference herein.

In some embodiment, IL-2 is a variant having at least 80%, preferably at least 90%, 95%, 98%, 99%, sequence identity with a mature wildtype human IL-2. The variant can be glycosylated or non-glycosylated.

IL-2 is commercially available, including for pharmaceutical uses, and it is authorized for use in human patients. Suitable commercial forms include, e.g.

Proleukin® (aldesleukin) is a recombinant unglycosylated des-alanyl-l, serine- 125 human interleukin-2, produced in E.coli.

Roncoleukin® is a recombinant human IL-2 produced in yeast.

In a preferred embodiment, IL-2 is aldesleukin. Aldesleukin is the active ingredient of Proleukin®. Aldesleukin is an unglycosylated variant of mature human IL-2 comprising two amino acid modifications as compared to the sequence of mature human IL-2: the deletion of the first amino acid (alanine) and the substitution of cysteine at position 125 by serine.

The amino acid sequence of aldesleukin is provided as SEQ ID NO:2.

IL-2 for use in the present invention is preferably in essentially pure form, e.g., at a purity of 95% or more, further preferably 96, 97, 98 or 99% pure.

The biological activity of IL-2 is typically determined in a standard cell proliferation assay using an IL-2 dependent cell line, such as CTLL-2 or HT-2.

Lor instance, the biological activity of IL-2 may be determined by a cell-based assay performed on HT-2 cell line (clone A5E, ATCC® CRL-1841™) whose growth is dependent on IL-2. Cell growth in the presence of a range of test interleukin-2 product is compared with the growth recorded with IL-2 international standard (WHO 2nd International Standard for INTERLEUKIN 2 (Human, rDNA derived) NIBSC code: 86/500). Cell growth is measured after addition and transformation of [3-(4,5-dimethylthiazol-2-yl)-5-(3- carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (inner salt, MTS) into formazan by active viable cells. Lormazan concentration is then measured by spectrophotometry at 490 nm.

In a preferred embodiment, IL-2 as used in the present invention is des-alanyl-l, serine- 125 human interleukin-2, preferably produced recombinantly. In a particular embodiment it is unglycosylated, preferably it is produced in E.coli. The IL-2 may be used alone or in combination with any other therapeutically active agent.

In a particular embodiment, the IL-2 is conjugated to a water-soluble polymer, such as polyethylene glycol (PEG). A preferred conjugate is described in patent application W02012/065086, wherein the conjugate comprises a water-soluble polymer such as PEG covalently attached via a releasable linkage to an amine group of an IL-2 moeity.

In a particular embodiment, the IL-2 may be mutated at position D109C (with the C residue being capable of binding a PEG moiety), as described e.g. in international patent application W02016/0025385.

In another particular embodiment, the IL-2 is fused to an immunoglobulin, preferably an IgG, preferably a human IgG, or preferably to a Fc region of an immunoglobulin. On may also use a particular fusion construct, that comprises two IL-2 proteins fused to one immunoglobulin, is disclosed e.g. in WO2014/023752 and WO2015/118016.

In another embodiment, the IL-2 is fused at the N-terminal end of a Fc moiety, either directly or preferably through a peptide linker, e.g. an 8 to 12 amino acid linker, as described e.g. in international patent application WO2016/014428.

Dosage and regimen

The standard measure of an amount IL-2 is the International Unit (IU), which technically is not a fixed weight but the amount that produces a fixed biological effect in a specific cell proliferation assay, as determined by the World Health Organization (WHO). The reason is that i) the weight varies depending on the exact sequence of the molecule and its glycosylation profile, and ii) what matters is the activity, not the weight of the molecule.

The principle of the International Unit is precisely to provide a standard to which any IL-2 molecule can be compared (regardless of their source, or their sequence, including wild-type or active variant sequences).

In practice, the WHO provide ampoules containing an IL-2 molecule that has been calibrated and serves as the reference to determine the dosage of a given preparation of IL-2 (again regardless of the source or sequence of said IL-2) defined by its potency. For instance, to determine the dosage of a given preparation of IL-2, the biological activity of the candidate IL-2 preparation is measured in a standard cell proliferation assay using an IL-2 dependent cell line, such as CTLL-2, and compared with the biological activity of the standard. The cells are grown in the presence of different doses of the standard. A dose-response effect of IL-2 is established, where the dose of IL-2 is plotted on the X axis as IU and the measure of proliferation (pr) is on the Y axis. When one wants to determine the activity of any IL-2 product of unknown activity, the product is used to grow the 11-2 dependent cells and the proliferation is measured. The pr value is then plotted on the Y axis and from that value a line parallel to the X axis is drawn. From the point of intersection of this line with the dose response line, a line parallel to the Y axis is then drawn. Its intersection with the X axis provides the activity of the candidate IL-2 product in IU.

Any change of the WHO standard ampoules do not impact the International Unit nor the determination of a dosage of any IL-2 preparation.

The lst standard (WHO international Standard coded 86/504, dated 1987) contained a purified glycosylated IL-2 derived from Jurkat cells and was arbitrarily assigned a potency of 100 IU/ampoule. As the stocks of the lst international standard (IS) were running low, the WHO had to replace it. The WHO provided another calibrated IL-2 ampoule, this time produced using E. coli. The 2nd standard ampoules contained 210 IU of biological activity per ampoule. The change of standard ampoules does not mean that the IU changes. So, determining the dosage of a test IL-2 preparation will not vary whether one uses the lst standard ampoule or the 2nd standard ampoule, or a subsequent standard ampoule, as a reference.

According to the invention, IL-2 is preferably administered at a dosage ranging from about 1 MlU/day to about 2 MlU/day. This dosage is particularly suitable for human subjects.

This dosage effectively activates Tregs without substantially activating Teffs. The consequence is a dramatic increase in the Treg/Teff balance in the subject. At this dosage IL-2 substantially avoids side effects, while very substantially inducing Tregs.

In a preferred embodiment, particularly advantageous for subcutaneous administration, IL-2 is administered at a dose of 1, 1.5 or 2 MlU/day.

According to the invention, the treatment typically comprises at least a first course wherein interleukin-2 is administered once per day during at least about 2 or 3 consecutive days, preferably during 3 to 7, still preferably during 4 to 5 consecutive days, preferably followed by a maintenance dose after about six days or about 1 to about 4 weeks.

The maintenance dose is typically administered during at least one month, preferably at least about 3 months, still preferably at least about 6 months. In a preferred embodiment, the maintenance dose is administered between about 3 months and about 12 months, preferably between about 6 months and about 12 months.

In a preferred embodiment, the maintenance treatment consists of an administration of interleukin-2 once or twice a week, or every one or two weeks. In a preferred embodiment, the maintenance treatment consists of an administration of interleukin-2 once or twice a week, every one or two weeks, during a period of at least one month, preferably from about 3 months to about 12 months.

Preferably the maintenance dosage is substantially the same as the first course dosage, or it can be a lower or higher dosage.

In a preferred embodiment, the treatment comprises at least a first course wherein interleukin- 2 is administered at a dosage of at most 3.5 MlU/day, preferably about 1 to about 2MIU/day, preferably 1-1.5 MlU/day, once per day during 2 or 3 to 7 days, preferably 5 days, followed by a maintenance dose after one to two weeks, of about 1 to about 2MIU/day, preferably 1-1.5 MlU/day every 2 weeks, during at least three months, preferably at least six months.

In another embodiment, especially when the IL-2 molecule is a variant with longer half-life and/or is conjugated to a moiety that improves the half-life of the conjugate, the regimen is adjusted to the extent the Treg increase during maintenance remains at least 1.3, 1.5, 1.7, 1.9, or at least twice the baseline Treg level. For that purpose, in an embodiment, the regimen may be defined as a first (induction) course consisting of a dosage of at most 3.5MIU one per day during 1 to 3 days, followed by a maintenance course after 1 to 4 weeks. Preferably the maintenance course then consists in an administration of IL-2 at a maintenance dosage, once every 2 weeks to once a month, during about 1 month, preferably 3 months, still preferably 6 months, or more.

In a particular embodiment, the subject is administered with IL-2 as the single active ingredient effective in treating Systemic sclerosis.

In another particular embodiment, the subject it administered with IL-2, as well as with other active ingredients, either simultaneously or sequentially. For instance, the subject may be administered with IL-2 in combination with immunosuppressant agent (methotrexate, mycophenolate mofetil or cyclophosphamide), corticosteroids, and/or with nonsteroidal anti inflammatory drugs (NSAIDs), and/or optionally associated with at least another symptomatic drug that aims at reducing the complications of internal organs (e.g. ACE inhibitors to prevent renal crisis and endothelin receptor antagonists, epoprostenol analogues, and phosphodiesterase-5 inhibitors for pulmonary arterial hypertension). However, in preferred embodiments, the dosage of such additional active ingredients can be reduced dramatically, reducing the risk and severity of side effects.

Administration forms and routes 11-2 may be administered using any convenient route, including parenteral, e.g. intradermal, subcutaneous, or intranasal route. The subcutaneous route is preferred. Oral, sublingual or buccal administrations are also encompassed.

IL-2 is typically administered in association (e.g., in solution, suspension, or admixture) with a pharmaceutically acceptable vehicle, carrier or excipient. Suitable excipients include any isotonic solution, saline solution, buffered solution, slow release formulation, etc. Liquid, lyophilized, or spray-dried compositions comprising IL-2 or variants thereof are known in the art and may be prepared as aqueous or nonaqueous solutions or suspensions. Preferably the pharmaceutical compositions comprise appropriate stabilizing agents, buffering agents, bulking agents, or combinations.

The Examples illustrate the invention without limiting its scope.

Examples

The case reports show that low-dose IL2 can tip the Treg/Teff balance in favor of Tregs and lead to clinical improvement in patients with systemic sclerosis.

Patient selection

Inclusion criteria for study were as follows:

1) documented diagnosis of Systemic sclerosis (ScS) according with ACR/EULAR criteria (Classification Criteria for Systemic Sclerosis: An ACR-EULAR Collaborative Initiative Arthritis Rheum 2013 Nov; 65(11): 2737-2747 doi: I (1 1002/art.38098)

2) moderately active disease defined by skin, muscular and joint involvement without pulmonary hypertension (PAPs<25mmHg)

3) under standard treatment (> 2 months) at the time of inclusion.

Exclusion criteria included co-infection with HBV or HIV, several organ damages (heart failure, renal crisis, or hepatic insufficiency, or pulmonary hypertension), pregnancy and drug addiction.

Treatment

Each patient received 1MUI /day of aldesleukin from Day-l to Day-5 (the induction period), and then every 2 weeks from Day- 15 to Day- 180 (the maintenance period). This protocol is referred to as“ldIL-2” (low dose IL-2) therapy. Patients are thereafter followed up for 2, 6 and 12 months.

Results

Case reports from the first 6 patients treated are presented below.

2-14-01-A-C: (Systemic Sclerosis with anti-Scl70+) female, 48 years old without regular treatment. Under ldIL-2 therapy, arthralgia has decreased by around 50%.

2-14-02-G-M: (Systemic Sclerosis with anti-centromere+) female, 72 years old without regular treatment. After three months of ldIL-2 therapy, muscular, articular and gastrointestinal symptoms (dysphagia) have decreased.

2-14-03 -O-M: (Reynolds Syndrome: Systemic Sclerosis and primary biliary cirrhosis with anti-centromere+, anti-SSA+, anti-GP2lO+,) female, 37 years old without regular treatment. After two months of therapy the patient reports greater elasticity of the skin. Furthermore, at three months of ldIL-2 therapy, the patient has dramatically decreased arthralgia and morning stiffness.

2-14-06-RV: (Reynolds Syndrome: Systemic Sclerosis with anti-centromere+ and primary biliary cirrhosis) female, 31 years old on regular treatment with hydroxychloroquine 400 mg/day. After three months of ldIL-2 therapy, the patient has dramatically decreased arthralgia.

2-14-08-BP: (Systemic Sclerosis with anti-centromere+) female, 54 years without regular treatment. Under ld IL-2 therapy, she dramatically improved skin involvement shown by a Rodnan’s score that decreasing from a value of 14 at baseline to a value of 5 after three and six months of therapy. See Figure.

Claims

1. Interleukin-2 for use in treating systemic sclerosis in a subject, wherein IL-2 is to be administered at a dose of 3.5 MlU/day or less.

2. Interleukin-2 for use according to claim 1, for alleviating at least one articular symptom associated with systemic sclerosis, such as arthralgia, puffy fingers or morning stiffness, or at least one extra-articular symptom associated with systemic sclerosis, such as skin involvement, vascular manifestations (Raynaud’s phenomenon), organ failure, lung fibrosis, gastrointestinal manifestations, cardiac disease, pulmonary hypertension, and fatigue.

3. Interleukin-2 for use according to claim 1 or 2, wherein it is to be administered at a dose of about 1-1.5 MlU/day.

4. Interleukin-2 for use according to any of claims 1 or 2, wherein the treatment comprises at least a first course wherein interleukin-2 is administered once per day during at least 2 or 3 consecutive days, preferably 3 to 7 days, preferably 4 to 5 consecutive days, followed by a maintenance treatment, preferably after about 1 to about 4 weeks.

5. Interleukin-2 for use according to claim 4, wherein the maintenance treatment consists of an administration of interleukin-2 once or twice a week, every one or two weeks, or once a month, during a period of at least one month, preferably from about 3 months to about 12 months.

6. Interleukin-2 for use according to any of claims 1 to 4, wherein IL-2 is administered repeatedly.

7. Interleukin-2 for use according to any of claims 1 to 6, wherein interleukin-2 is administered by subcutaneous route.

8. Interleukin-2 for use according to any of claims 1 to 7, wherein the treatment is preventive, the subject being susceptible to develop systemic sclerosis.

9. Interleukin-2 for use according to any of claims 1 to 8, wherein the treatment reduces the number and/or severity of inflammatory episodes.

10. Interleukin-2 for use according to any of claims 1 to 9, wherein the subject is human.

11. Interleukin-2 for use according to any of claims 1 to 10, wherein IL-2 is conjugated to at least one PEG moiety.

12. Interleukin-2 for use according to any of claims 1 to 10, wherein IL-2 is conjugated to an immunoglobulin, or a Fc region of an immunoglobulin.

13. Interleukin-2 for use according to any of claims 1 to 12, wherein IL-2 is a wherein said 11-2 is human IL-2 or an active analogue thereof, which active analogue has at least 85% amino acid identity with human wild-type IL-2.

14. Interleukin-2 for use according to claim 13, wherein said IL-2 is an active analogue of human IL-2 which has at least 90% amino acid identity with human wild-type IL-2.

15. Interleukin-2 for use according to claim 14, wherein said IL-2 is aldesleukin.