THU0198 EFFICACY AND SAFETY OF FILGOTINIB FOR PATIENTS WITH RHEUMATOID ARTHRITIS WITH INADEQUATE RESPONSE TO METHOTREXATE: FINCH 1 52-WEEK RESULTS

Background:

Filgotinib (FIL) is an oral, potent, selective JAK1 inhibitor. FINCH 1 (NCT02889796) assessed FIL efficacy and safety in patients (pts) with rheumatoid arthritis (RA) with inadequate response to methotrexate (MTX-IR); primary outcome results at week (W)12 and W24 were previously reported.1

Objectives:

To present FINCH 1 W52 results.

Methods:

This global, phase 3, double-blind, active- and placebo (PBO)-controlled study randomised MTX-IR pts with active RA on a background of stable MTX 3:3:2:3 to oral FIL 200 mg or FIL 100 mg once daily, subcutaneous adalimumab (ADA) 40 mg every 2W, or PBO up to W52; pts receiving PBO at W24 were rerandomised to FIL 100 or 200 mg. Efficacy was assessed from clinical, radiographic, and pt-reported outcomes; W52 comparisons were not adjusted for multiplicity. Safety endpoints included adverse events (AEs) and laboratory abnormalities.

Results:

Of 1755 treated pts, 1417 received study drug through W52. The majority (81.8%) were female, mean (standard deviation [SD]) RA duration was 7.8 (7.6) years, and baseline mean (SD) DAS28(CRP) was 5.7 (0.9). FIL efficacy was sustained through W52; 54%, 43%, and 46% of pts receiving FIL 200 and 100 mg and ADA, respectively, had W52 DAS28(CRP) <2.6 (nominal p for FIL 200 vs ADA = 0.024) (Figures 1–2, Table 1). FIL safety profile through W52 was consistent with W24 data. AEs of interest were infrequent and balanced among treatments (Table 2); 82 pts (4.7%) discontinued treatment due to AEs.

Table 1.

Efficacy outcomes at week 52

FIL 200 mg(n = 475)FIL 100 mg(n = 480)ADA(n = 325)ACR20/50/70, %78/62/4476/59/3874/59/39DAS28(CRP) ≤3.2, %66+5959mTSSa0.18+++0.450.61HAQ-DIb−0.93+−0.85−0.85SF-36 PCSb12.011.512.4FACIT-Fb11.912.211.7

aLeast squares mean change from baseline.

bMean change from baseline.

+p <0.05,+++p <0.001 vs ADA; not adjusted for multiplicity.

ADA, adalimumab; FIL, filgotinib; mTSS, modified van der Heijde TSS.

Table 2.

Treatment-emergent AEs through week 52

Event, n (%)FIL 200(n = 475)FIL 100 mg(n = 480)ADA(n = 325)All AEs352 (74.1)350 (72.9)239 (73.5)Serious AEs35 (7.4)40 (8.3)22 (6.8)Infection206 (43.4)194 (40.4)129 (39.7)Serious infection13 (2.7)13 (2.7)10 (3.1)Herpes zoster6 (1.3)4 (0.8)2 (0.6)VTE1 (0.2)01 (0.3)MACE (adjudicated)02 (0.4)1 (0.3)Malignancy (excluding NMSC)2 (0.4)2 (0.4)2 (0.6)NMSC1 (0.2)1 (0.2)0Death3 (0.6)1 (0.2)1 (0.3)

Data omitted for patients rerandomised from placebo to FIL.

ADA, adalimumab; AE, adverse event; FIL, filgotinib; MACE, major adverse cardiovascular event; NMSC, nonmelanoma skin cancer; VTE, venous thromboembolism.

Conclusion:

Through W52, both FIL 200 and 100 mg showed sustained efficacy based on clinical and pt-reported outcomes and radiographic progression and were well tolerated in MTX-IR pts with RA, with faster onset and numerically greater efficacy for FIL 200 vs 100 mg.

References:

[1]Combe et al.,Ann Rheum Dis.2019; 78 (Suppl 2):77–8.

Disclosure of Interests:

Bernard Combe Grant/research support from: Novartis, Pfizer, Roche-Chugai, Consultant of: AbbVie; Gilead Sciences, Inc.; Janssen; Eli Lilly and Company; Pfizer; Roche-Chugai; Sanofi, Speakers bureau: Bristol-Myers Squibb; Gilead Sciences, Inc.; Eli Lilly and Company; Merck Sharp & Dohme; Pfizer; Roche-Chugai; UCB, Alan Kivitz Shareholder of: AbbVie, Amgen, Gilead, GSK, Pfizer Inc, Sanofi, Consultant of: AbbVie, Boehringer Ingelheim,,Flexion, Genzyme, Gilead, Janssen, Novartis, Pfizer Inc, Regeneron, Sanofi, SUN Pharma Advanced Research, UCB, Paid instructor for: Celgene, Genzyme, Horizon, Merck, Novartis, Pfizer, Regeneron, Sanofi, Speakers bureau: AbbVie, Celgene, Flexion, Genzyme, Horizon, Merck, Novartis, Pfizer Inc, Regeneron, Sanofi, Yoshiya Tanaka Grant/research support from: Asahi-kasei, Astellas, Mitsubishi-Tanabe, Chugai, Takeda, Sanofi, Bristol-Myers, UCB, Daiichi-Sankyo, Eisai, Pfizer, and Ono, Consultant of: Abbvie, Astellas, Bristol-Myers Squibb, Eli Lilly, Pfizer, Speakers bureau: Daiichi-Sankyo, Astellas, Chugai, Eli Lilly, Pfizer, AbbVie, YL Biologics, Bristol-Myers, Takeda, Mitsubishi-Tanabe, Novartis, Eisai, Janssen, Sanofi, UCB, and Teijin, Désirée van der Heijde Consultant of: AbbVie, Amgen, Astellas, AstraZeneca, BMS, Boehringer Ingelheim, Celgene, Cyxone, Daiichi, Eisai, Eli-Lilly, Galapagos, Gilead Sciences, Inc., Glaxo-Smith-Kline, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sanofi, Takeda, UCB Pharma; Director of Imaging Rheumatology BV, J-Abraham Simon-Campos: None declared, Herbert S.B. Baraf Grant/research support from: Horizon; Gilead Sciences, Inc.; Pfizer; Janssen; AbbVie, Consultant of: Horizon; Gilead Sciences, Inc.; Merck; AbbVie, Speakers bureau: Horizon, Uma Kumar: None declared, Franziska Matzkies Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Beatrix Bartok Shareholder of: Gilead Sciences Inc., Employee of: Gilead Sciences Inc., Lei Ye Shareholder of: Gilead Sciences Inc., Employee of: Gilead Sciences Inc., Ying Guo Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Chantal Tasset Shareholder of: Galapagos (share/warrant holder), Employee of: Galapagos, John Sundy Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Angelika Jahreis Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Neelufar Mozaffarian Shareholder of: Gilead, Employee of: Gilead, Robert B.M. Landewé Consultant of: AbbVie; AstraZeneca; Bristol-Myers Squibb; Eli Lilly & Co.; Galapagos NV; Novartis; Pfizer; UCB Pharma, Sang-Cheol Bae: None declared, Edward Keystone Grant/research support from: AbbVie; Amgen; Gilead Sciences, Inc; Lilly Pharmaceuticals; Merck; Pfizer Pharmaceuticals; PuraPharm; Sanofi, Consultant of: AbbVie; Amgen; AstraZeneca Pharma; Bristol-Myers Squibb Company; Celltrion; F. Hoffman-La Roche Ltd.; Genentech, Inc; Gilead Sciences, Inc.; Janssen, Inc; Lilly Pharmaceuticals; Merck; Myriad Autoimmune; Pfizer Pharmaceuticals, Sandoz, Sanofi-Genzyme, Samsung Bioepsis., Speakers bureau: AbbVie; Amgen; Bristol-Myers Squibb; Celltrion; F. Hoffman-La Roche Ltd, Janssen, Inc; Merck; Pfizer Pharmaceuticals; Sanofi-Genzyme; UCB, Peter Nash Grant/research support from: AbbVie, Bristol-Myers Squibb, Celgene, Eli Lilly and Company, Gilead, Janssen, MSD, Novartis, Pfizer Inc, Roche, Sanofi, UCB, Consultant of: AbbVie, Bristol-Myers Squibb, Celgene, Eli Lilly, Gilead, Janssen, MSD, Novartis, Pfizer Inc, Roche, Sanofi, UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Celgene, Eli Lilly, Gilead, Janssen, MSD, Novartis, Pfizer Inc, Roche, Sanofi, UCB

SAT0158 EFFICACY AND SAFETY OF FILGOTINIB IN METHOTREXATE-NAÏVE PATIENTS WITH RHEUMATOID ARTHRITIS: FINCH 3 52-WEEK RESULTS

Background:

Filgotinib (FIL) is a potent, selective JAK 1 inhibitor. FINCH 3 assessed FIL efficacy and safety in methotrexate (MTX)-naïve patients (pts) with rheumatoid arthritis (RA); week (W)24 primary outcome results were previously presented.1

Objectives:

To report FINCH 3 (NCT02886728) results through W52.

Methods:

This global, phase 3, double-blind, active-controlled study randomised MTX-naïve pts with moderately to severely active RA 2:1:1:2 to oral FIL 200 mg once daily + MTX ≤20 mg weekly, FIL 100 mg + MTX, FIL 200 mg monotherapy (mono) + placebo (PBO), or PBO + MTX up to W52. Comparisons at W52 were not adjusted for multiplicity. Safety was assessed from adverse events and laboratory abnormalities.

Results:

Of 1249 treated pts, 975 received study drug through W52. FIL efficacy was sustained up to W52. Treatment with FIL + MTX or FIL mono increased proportions of pts achieving ACR20/50/70 and clinical disease remission by DAS28(CRP) <2.6 (FIL 200 mg + MTX, 53%; FIL mono, 46%), CDAI, SDAI, and Boolean criteria; improved HAQ-DI; and halted radiographic progression vs MTX alone (Table 1 andFigure). Safety was consistent with W24 data (Table 2).

Table 1.

Efficacy outcomes at week 52

FIL 200 mg + MTX (n = 416)FIL 100 mg + MTX (n = 207)FIL 200 mg(n = 210)MTX(n = 416)ACR20, %75.0***73.4**74.8***61.8ACR50, %62.3***59.4**61.4**48.3ACR70, %47.8***40.1*45.2***29.8mTSSa0.21***0.27*0.23**0.74HAQ-DIb−1.00***−0.97−0.95*−0.88

aLeast-squares mean change from baseline.

bMean change from baseline.

*, p <0.05;**, p <0.01;***, p <0.001 vs MTX alone; not adjusted for multiplicity.

FIL, filgotinib; mTSS, van der Heijde modified total Sharp score; MTX, methotrexate.

Table 2.

Safety outcomes through week 52

Event, n (%)FIL 200 mg + MTX(n = 416)FIL 100 mg + MTX(n = 207)FIL 200 mg(n = 210)MTX(n = 416)All AEs318 (76.4)164 (79.2)143 (68.1)305 (73.3)Serious AEs26 (6.3)13 (6.3)17 (8.1)28 (6.7)Infection148 (35.6)76 (36.7)75 (35.7)157 (37.7)Serious infection5 (1.2)3 (1.4)5 (2.4)8 (1.9)Herpes zoster6 (1.4)3 (1.4)4 (1.9)4 (1.0)VTE0004 (1.0)MACE (adjudicated)4 (1.0)1 (0.5)2 (1.0)2 (0.5)Malignancya1 (0.2)004 (1.0)NMSC2 (0.5)001 (0.2)Death3 (0.7)b1 (0.5)c00

aExcluding NMSC.

b1 lupus cardiomyopathy, 1 atypical interstitial pneumonia, 1 non–treatment-emergent cardiovascular death.

cDissecting cerebral and vertebral aneurysm.

AE, adverse event; FIL, filgotinib; MACE, major adverse cardiovascular event; MTX, methotrexate; NMSC, nonmelanoma skin cancer; VTE, venous thromboembolism.

Conclusion:

Efficacy of FIL 200 mg + MTX, FIL 100 mg + MTX, and FIL 200 mg mono was sustained through W52, with faster onset1and consistently numerically greater efficacy for FIL 200 vs 100 mg. No new safety signals were observed.

References:

[1]Westhovens, et al.Ann Rheum Dis.2019;78(Suppl2):259–60.

Disclosure of Interests:

Rene Westhovens Grant/research support from: Celltrion Inc, Galapagos, Gilead, Consultant of: Celltrion Inc, Galapagos, Gilead, Speakers bureau: Celltrion Inc, Galapagos, Gilead, William Rigby Consultant of: Gilead Sciences, Inc., Désirée van der Heijde Consultant of: AbbVie, Amgen, Astellas, AstraZeneca, BMS, Boehringer Ingelheim, Celgene, Cyxone, Daiichi, Eisai, Eli-Lilly, Galapagos, Gilead Sciences, Inc., Glaxo-Smith-Kline, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sanofi, Takeda, UCB Pharma; Director of Imaging Rheumatology BV, Daniel Ching Grant/research support from: AbbVie, Gilead Sciences, Inc., Pfizer, Sanofi, Consultant of: AbbVie, Pfizer, Speakers bureau: AbbVie, William Stohl Grant/research support from: GlaxoSmithKline, Consultant of: Janssen Research & Development, Jonathan Kay Grant/research support from: Gilead Sciences, Inc., Pfizer, Novartis Pharmaceuticals Corporation, Consultant of: Alvotech Suisse AG; Arena Pharmaceuticals, Inc.; Boehringer Ingelheim GmbH; Celltrion Healthcare Co. Ltd.; Merck Sharp & Dohme Corp.; Mylan Inc.; Novartis AG; Samsung Bioepis; Sandoz, Inc; UCB, Inc., Arvind Chopra Grant/research support from: Zydus Pharamceutical Ltd India, Beatrix Bartok Shareholder of: Gilead Sciences Inc., Employee of: Gilead Sciences Inc., Franziska Matzkies Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Zhaoyu Yin Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Ying Guo Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Chantal Tasset Shareholder of: Galapagos (share/warrant holder), Employee of: Galapagos, John Sundy Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Angelika Jahreis Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Neelufar Mozaffarian Shareholder of: Gilead, Employee of: Gilead, Osvaldo Messina Speakers bureau: Amgen; Americas Health Foundation; Pfizer, Robert B.M. Landewé Consultant of: AbbVie; AstraZeneca; Bristol-Myers Squibb; Eli Lilly & Co.; Galapagos NV; Novartis; Pfizer; UCB Pharma, Tatsuya Atsumi Grant/research support from: Eli Lily Japan K.K., Alexion Pharmaceuticals, Inc., Bristol-Myers Squibb Co., AbbVie Inc., Daiichi Sankyo Co., Ltd., Pfizer Inc., Chugai Pharmaceutical Co., Ltd., Mitsubishi Tanabe Pharma Co., Astellas Pharma Inc., Consultant of: Gilead Sciences, Inc., Eli Lilly Japan K.K., UCB Japan Co. Ltd., AbbVie Inc., Daiichi Sankyo Co., Ltd., Pfizer Inc., Chugai Pharmaceutical Co., Ltd., Speakers bureau: Eli Lilly Japan K.K., UCB Japan Co. Ltd., Bristol-Myers Squibb Co., AbbVie Inc., Eisai Co. Ltd., Otsuka Pharmaceutical Co., Ltd., Daiichi Sankyo Co., Ltd., Pfizer Inc., Chugai Pharmaceutical Co., Ltd., Mitsubishi Tanabe Pharma Co., Takeda Pharmaceutical Co., Ltd., Astellas Pharma Inc., Gerd Rüdiger Burmester Consultant of: AbbVie Inc, Eli Lilly, Gilead, Janssen, Merck, Roche, Pfizer, and UCB Pharma, Speakers bureau: AbbVie Inc, Eli Lilly, Gilead, Janssen, Merck, Roche, Pfizer, and UCB Pharma

Comparison of clinical and pharmacokinetic profiles of etanercept 25 mg twice weekly and 50 mg once weekly in patients with psoriasis

BACKGROUND

Etanercept is a tumour necrosis factor antagonist that is approved in the U.S.A., Canada and Europe for treating adult patients with chronic moderate to severe plaque psoriasis.

OBJECTIVES

To assess whether clinical efficacy, safety and pharmacokinetic (PK) profiles of etanercept 50 mg once weekly are comparable to etanercept 25 mg twice weekly.

METHODS

Patients from a U.S. phase 3 study and a global phase 3 study were subsequently enrolled in an open-label extension study (extension study) where they all received etanercept at a dose of 50 mg once weekly for an initial 12 weeks. Patients who had received at least 24 weeks of etanercept 25 mg twice weekly in the global phase 3 study and were enrolled in the extension study (n = 265) were assessed for efficacy and safety at extension study baseline and after 12 weeks of etanercept 50 mg once weekly. Efficacy endpoints included the Psoriasis Area and Severity Index (PASI), the Dermatology Life Quality Index and the Physician's Global Assessment of psoriasis. In addition, PK profiles from patients in the U.S. phase 3 study were compared with PK profiles from another set of patients in the extension study. Comparison was made between a subset of patients receiving etanercept 25 mg twice weekly dosing in the U.S. phase 3 study (n = 13) and those receiving etanercept 50 mg once weekly in the extension study (n = 84).

RESULTS

The mean PASI score was 5.77 at extension study baseline after treatment with etanercept 25 mg twice weekly, which was sustained at 5.82 after 12 weeks of etanercept 50 mg once weekly. Similar results were observed in other efficacy endpoints. Etanercept 50 mg once weekly was generally well tolerated. No new safety findings were reported. PK profiles overlapped extensively between the two dosing regimens.

CONCLUSIONS

In this report, we demonstrate that efficacy, safety and PK profiles were comparable between etanercept 25 mg twice weekly and 50 mg once weekly in patients who had received at least 24 weeks of etanercept 25 mg twice weekly prior to receiving etanercept 50 mg once weekly in the extension study.

Patient-reported outcomes of psoriasis improvement with etanercept therapy: results of a randomized phase III trial

BACKGROUND

Etanercept, a soluble tumour necrosis factor receptor, lessens the severity of psoriasis as measured by physician-reported clinical outcomes. Equally important is the patient perspective on the effect of etanercept therapy on daily life.

OBJECTIVES

To assess patient-reported outcomes (PROs) in patients with psoriasis receiving etanercept therapy.

METHODS

In this multinational, randomized, phase III trial, patients with psoriasis received placebo (n = 193), etanercept 50 mg per week (n = 196) or etanercept 50 mg twice weekly (n = 194) during the initial 12-week, double-blind period. Thereafter, all patients received open-label etanercept (50 mg per week). The following PROs were assessed: Dermatology Life Quality Index (DLQI), Short Form-36 Health Survey (SF-36), patient rating of pruritus, and patient global assessment of psoriasis.

RESULTS

At week 12, DLQI total score improved by 65-70% in patients receiving etanercept compared with 6% in patients receiving placebo (P < 0.0001), and improvement in DLQI was clinically meaningful (> or = 5-point improvement or 0 score) for 72-77% of patients receiving etanercept therapy. All DLQI and SF-36 subscales and the SF-36 physical and mental component summary scores demonstrated significantly greater improvement with etanercept therapy than with placebo, illustrating that etanercept benefits patients with psoriasis across multiple domains that contribute to health-related quality of life. With etanercept therapy, distributions of patient ratings of pruritus and global assessment of disease shifted from moderate to severe (baseline) to minimal to good (week 12). Etanercept-induced benefits of PROs were maintained for patients who reduced their dose after 12 weeks.

CONCLUSIONS

Etanercept therapy improves PROs in patients with psoriasis and makes a meaningful difference to their lives. These results support the efficacy profile of physician-reported clinical measures while providing a more complete understanding of the benefits experienced by patients with psoriasis treated with etanercept.

Effects of two novel cationic staphylococcal proteins (NP-tase and p70)and enterotoxin B on IgE synthesis and interleukin-4 and interferon-gamma production in patients with atopic dermatitis

We have characterized the cell-mediated and humoral immune response of patients with atopic dermatitis (AD) and healthy controls in response to two novel staphylococcal antigens (NP-tase, p70) and the superantigen staphylococcal enterotoxin B (SEB). The parameters studied were IgE, interleukin (IL)-4 and interferon (IFN)-gamma synthesis by peripheral blood mononuclear cells (PBMC) after stimulation with NP-tase, p70 and SEB in vitro. Both antigens, as well as SEB, induced IL-4 and IFN-gamma secretion in patients and controls. However, patients with AD showed a significantly diminished IFN-gamma production in response to NP-tase or SEB. Furthermore, we demonstrated a good correlation between antigen-stimulated IgE production and the IL-4/IFN-gamma ratio in vitro. A distinct subgroup of PBMC showed impaired IFN-gamma synthesis and enhanced IL-4 secretion after incubation with p70 or NP-tase. These data support evidence that a subgroup of patients with AD, synthesizing low levels of IFN-gamma after stimulation with staphylococcal antigens, may have impaired abilities to clear Staphylococcus aureus colonization. Persistent staphylococcal antigens could then be responsible for inflammatory and allergic skin reactions in patients with AD. We therefore conclude that, besides superantigens, staphylococcal antigens may also play a part in the pathogenesis of AD.

A double-blind, placebo-controlled, crossover therapy study with natural human IL-2 (nhuIL-2) in combination with regular intravenous gammaglobulin (IVIG) infusions in 10 patients with common variable immunodeficiency (CVID)

Ten CVID patients with defective IL-2 synthesis in vitro were treated with nhuIL-2 in a placebo-controlled, double blind, crossover therapy study during a period of 12 months. No severe side-effects of nhuIL-2 were recorded. Marginal serum nhuIL-2 levels were measurable in individual patients only during the therapy phase. Serum levels of soluble IL-2 receptors were unaffected by the therapy. nhuIL-2 and placebo groups did not differ significantly with respect to requirement of IVIG substitutions which were performed whenever serum IgG levels dropped below 5 g/l: a total of 53 IVIG infusions (corresponding to 17.6 g IgG/month per patient) was necessary during the placebo phase, and 48 infusions (16.4 g IgG/month per patient) during the nhuIL-2 treatment phase. Thus, nhuIL-2 therapy was ineffective in improving spontaneous IgG synthesis in vivo. Nevertheless, the group of patients receiving nhuIL-2 during the first 6 months of the study exhibited a significant reduction of severe infections (n = 25) during the following 6 months of placebo treatment (n = 7) (P<0.045). The infection score dropped in this group from 181 to 23 (P<0.015). Patients of the second group receiving first placebo and then nhuIL-2 did not experience a significant difference in number and score of infectious episodes: 25 infections were recorded during the first 6 months and 24 during the following 6 months. We suppose that nhuIL-2 therapy of CVID patients reduces susceptibility to severe infections, possibly via the induction of a specific antibody response, which is effective at the earliest 6 months after initiating nhuIL-2 therapy.

Two novel cationic staphylococcal proteins induce IL-2 secretion, proliferation and immunoglobulin synthesis in peripheral blood mononuclear cells (PBMC) of both healthy controls and patients with common variable immunodeficiency (CVID)

Two cationic proteins, a neutral phosphatase (NP-tase) and a 70-kD protein (p70) were isolated from Staphylococcus aureus by ion exchange chromatography. We compared their properties to those of the well established B cell mitogen of whole, fixed Staph. aureus strain Cowan I cells (SAC). Both purified proteins were able to induce immunoglobulin synthesis in PBMC cultures of healthy donors. NP-tase and p70 also induced immunoglobulin synthesis of PBMC from those patients with CVID who were also responsive to SAC plus IL-2 stimulation. Immunoglobulin synthesis in response to NP-tase and to p70 was time- and dose-dependent and could be inhibited by addition of specific antibodies against the proteins. In contrast to SAC, no addition of exogenous IL-2 was necessary to obtain maximal immunoglobulin synthesis induced by NP-tase or p70. However, neither protein was able to induce immunoglobulin synthesis in B cell-enriched cultures. High amounts of IL-2 were found in supernatants of PBMC from healthy donors following stimulation with low concentrations of NP-tase or p70, and this was associated with vigorous lymphocyte proliferation. Both proteins behave like typical antigens, and not like lectins or superantigens, since an NP-tase-stimulated T cell line showed an antigen-specific, MHC-restricted secondary response. In addition, no preferential T cell receptor V beta chain usage was found with eight V beta-specific MoAb. It is likely that the two proteins induce antigen-specific T cell activation, which is then followed by polyclonal activation of B cells via CD40 receptors and cytokine release.

[Preliminary results in a placebo-controlled, double-blind crossover clinical trial with human interleukin-2 (n-IL-2) in patients with variable immunodeficiency syndrome (CVID)]

Ten CVID patients with an in vitro defect for IL-2-synthesis were treated for 12 months in a placebo-controlled double-blind crossover therapy study with human natural IL-2 s.c. There were no severe side effects of n-IL-2 recorded. Serum levels of soluble IL-2 receptors were unaffected by the therapy. Serum IL-2 levels were only measurable in single patients during the therapy phase. Since verum and placebo groups did not differ with respect to requirement for intravenous gammaglobulin substitutions, n-IL-2 therapy was uneffective in switching on IgG synthesis in vivo. Nevertheless, there was an elevation in vitro of IgM synthesis in 5 patients and of IgG synthesis in 4 patients during n-IL-2 therapy after stimulation of patients' lymphocytes with staphylococcus aureus Cowan I (SAC) plus n-IL-2 or with Pokeweed Mitogen (PWM) without n-IL-2. Additionally, an elevated IL-2-synthesis in vitro was recorded after OKT3 stimulation for 3 CVID patients. There was a significant reduction of severe infections from 25 during the first 6 months of the study to 7 infections during the following 6 months, in the group of patients which received n-IL-2 first. In the second group, which received placebo first, there were no significant differences between placebo and n-IL-2 therapy phase detectable (25 infections during the first 6 months of the study and 24 severe infections in the second phase).(ABSTRACT TRUNCATED AT 250 WORDS)

Possible role of IL-2 deficiency for hypogammaglobulinaemia in patients with common variable immunodeficiency

Common variable immunodeficiency (CVID) patients are unable to produce specific immunoglobulins after antigen contact in vivo. The aim of this study was to investigate whether in some cases of CVID a decreased de novo synthesis of IL-2 might be the cause of immunodeficiency and whether this deficiency can be corrected by IL-2 supplementation in vitro. Mononuclear cells from 17 CVID patients and from 10 healthy controls were cultured with monoclonal anti-CD3 antibody OKT3, pokeweed mitogen (PWM) or tetanus toxoid (TT) to stimulate IL-2 synthesis. In parallel, in vitro IgG and IgM synthesis was stimulated with Staphylococcus aureus Cowan I (SAC), PWM or TT in the presence or absence of IL-2. While lymphocytes of 11 out of 17 patients produced low to normal amounts of IL-2 upon stimulation with anti-CD3, only three patients showed low IL-2 production in response to PWM and five in response to TT. Regarding immunoglobulin synthesis in vitro, five patients completely failed to produce IgM or IgG upon stimulation with PWM, SAC or TT irrespective of the addition of IL-2. By contrast, four patients did not show any defect in vitro and synthesized normal amounts of IgM and IgG with any of the three stimuli. Finally, eight patients could be reconstituted for PWM-, SAC- and TT-induced IgM and/or IgG synthesis in vitro, by adding IL-2 to the culture system. This enhancing effect of IL-2 could be blocked by adding anti-IL-2 receptor antibodies to the cultures. Our findings indicate that a defective IL-2 synthesis after antigen stimulation may be one reason for the impaired immunoglobulin production in some cases of CVID.