Concordance and discordance in SLE clinical trial outcome measures: analysis of three anifrolumab phase 2/3 trials.

OBJECTIVES: In the anifrolumab systemic lupus erythematosus (SLE) trial programme, there was one trial (TULIP-1) in which BILAG-based Composite Lupus Assessment (BICLA) responses favoured anifrolumab over placebo, but the SLE Responder Index (SRI(4)) treatment difference was not significant. We investigated the degree of concordance between BICLA and SRI(4) across anifrolumab trials in order to better understand drivers of discrepant SLE trial results. METHODS: TULIP-1, TULIP-2 (both phase 3) and MUSE (phase 2b) were randomised, 52-week trials of intravenous anifrolumab (300 mg every 4 weeks, 48 weeks; TULIP-1/TULIP-2: n=180; MUSE: n=99) or placebo (TULIP-1: n=184, TULIP-2: n=182; MUSE: n=102). Week 52 BICLA and SRI(4) outcomes were assessed for each patient. RESULTS: Most patients (78%-85%) had concordant BICLA and SRI(4) outcomes (Cohen's Kappa 0.6-0.7, nominal p<0.001). Dual BICLA/SRI(4) response rates favoured anifrolumab over placebo in TULIP-1, TULIP-2 and MUSE (all nominal p≤0.004). A discordant TULIP-1 BICLA non-responder/SRI(4) responder subgroup was identified (40/364, 11% of TULIP-1 population), comprising more patients receiving placebo (n=28) than anifrolumab (n=12). In this subgroup, placebo-treated patients had lower baseline disease activity, joint counts and glucocorticoid tapering rates, and more placebo-treated patients had arthritis response than anifrolumab-treated patients. CONCLUSIONS: Across trials, most patients had concordant BICLA/SRI(4) outcomes and dual BICLA/SRI(4) responses favoured anifrolumab. A BICLA non-responder/SRI(4) responder subgroup was identified where imbalances of key factors driving the BICLA/SRI(4) discordance (disease activity, glucocorticoid taper) disproportionately favoured the TULIP-1 placebo group. Careful attention to baseline disease activity and monitoring glucocorticoid taper variation will be essential in future SLE trials. TRIAL REGISTRATION NUMBERS: NCT02446912 and NCT02446899.

A CD40L-targeting protein reduces autoantibodies and improves disease activity in patients with autoimmunity.

The CD40/CD40L axis plays a central role in the generation of humoral immune responses and is an attractive target for treating autoimmune diseases in the clinic. Here, we report the generation and clinical results of a CD40L binding protein, VIB4920, which lacks an Fc domain, therefore avoiding platelet-related safety issues observed with earlier monoclonal antibody therapeutics that targeted CD40L. VIB4920 blocked downstream CD40 signaling events, resulting in inhibition of human B cell activation and plasma cell differentiation, and did not induce platelet aggregation in preclinical studies. In a phase 1 study in healthy volunteers, VIB4920 suppressed antigen-specific IgG in a dose-dependent fashion after priming and boosting with the T-dependent antigen, KLH. Furthermore, VIB4920 significantly reduced circulating Ki67+ dividing B cells, class-switched memory B cells, and a plasma cell gene signature after immunization. In a phase 1b proof-of-concept study in patients with rheumatoid arthritis, VIB4920 significantly decreased disease activity, achieving low disease activity or clinical remission in more than 50% of patients in the two higher-dose groups. Dose-dependent decreases in rheumatoid factor autoantibodies and Vectra DA biomarker score provide additional evidence that VIB4920 effectively blocked the CD40/CD40L pathway. VIB4920 demonstrated a good overall safety profile in both clinical studies. Together, these data demonstrate the potential of VIB4920 to significantly affect autoimmune disease and humoral immune activation and to support further evaluation of this molecule in inflammatory conditions.

Mavrilimumab, a Fully Human Granulocyte-Macrophage Colony-Stimulating Factor Receptor α Monoclonal Antibody: Long-Term Safety and Efficacy in Patients With Rheumatoid Arthritis.

OBJECTIVE: Mavrilimumab, a human monoclonal antibody, targets granulocyte-macrophage colony-stimulating factor receptor α. We undertook to determine the long-term safety and efficacy of mavrilimumab in rheumatoid arthritis patients in 2 phase IIb studies (1071 and 1107) and in 1 open-label extension study (ClinicalTrials.gov identifier: NCT01712399). METHODS: In study 1071, patients with an inadequate response to disease-modifying antirheumatic drugs (DMARDs) received mavrilimumab (30, 100, or 150 mg) or placebo every other week plus methotrexate. In study 1107, patients with an inadequate response to anti-tumor necrosis factor agents and/or DMARDs received 100 mg mavrilimumab every other week or 50 mg golimumab every 4 weeks plus methotrexate. Patients entering the open-label extension study received 100 mg mavrilimumab every other week plus methotrexate. Long-term safety and efficacy of mavrilimumab were assessed. RESULTS: A total of 442 patients received mavrilimumab (14 of 245 patients from study 1071, 9 of 70 patients from study 1107, and 52 of 397 patients from the open-label extension study discontinued mavrilimumab treatment throughout the studies). The cumulative safety exposure was 899 patient-years; the median duration of mavrilimumab treatment was 2.5 years (range 0.1-3.3 years). The most common treatment-emergent adverse events (AEs) were nasopharyngitis (n = 69; 7.68 per 100 patient-years) and bronchitis (n = 51; 5.68 per 100 patient-years). At weeks 74 and 104, 3.5% and 6.2% of patients, respectively, demonstrated reduction in forced expiratory volume in 1 second, while 2.9% and 3.4% of patients, respectively, demonstrated reduction in forced vital capacity (>20% reduction from baseline to <80% predicted). Most pulmonary changes were transient and only infrequently associated with AEs. Mavrilimumab at 100 mg every other week demonstrated sustained efficacy; at week 122, 65.0% of patients achieved a Disease Activity Score in 28 joints using the C-reactive protein level (DAS28-CRP) of <3.2, and 40.6% of patients achieved a DAS28-CRP of <2.6. CONCLUSION: Long-term treatment with mavrilimumab maintained response and was well-tolerated with no increased incidence of treatment-emergent AEs. Safety data were comparable with those from both phase IIb qualifying studies.

A Randomized Phase IIb Study of Mavrilimumab and Golimumab in Rheumatoid Arthritis.

OBJECTIVE: This 24-week, phase IIb, double-blind study was undertaken to evaluate the efficacy and safety of mavrilimumab (a monoclonal antibody to granulocyte-macrophage colony-stimulating factor receptor α) and golimumab (a monoclonal antibody to tumor necrosis factor [anti-TNF]) in patients with rheumatoid arthritis (RA) who have had an inadequate response to disease-modifying antirheumatic drugs (DMARDs) (referred to as DMARD-IR) and/or inadequate response to other anti-TNF agents (referred to as anti-TNF-IR). METHODS: Patients with active RA and a history of DMARD-IR (≥1 failed regimen) or DMARD-IR (≥1 failed regimen) and anti-TNF-IR (1-2 failed regimens) were randomized 1:1 to receive either mavrilimumab 100 mg subcutaneously every other week or golimumab 50 mg subcutaneously every 4 weeks alternating with placebo every 4 weeks, administered concomitantly with methotrexate. The primary end points were the American College of Rheumatology 20% improvement (ACR20), 50% improvement, and 70% improvement response rates at week 24, percentage of patients achieving a Disease Activity Score in 28 joints using C-reactive protein level (DAS28-CRP) of <2.6 at week 24, percentage of patients with a score improvement of >0.22 on the Health Assessment Questionnaire (HAQ) disability index (DI) at week 24, and safety/tolerability measures. This study was not powered to formally compare the 2 treatments. RESULTS: At week 24, differences in the ACR20, ACR50, and ACR70 response rates between the mavrilimumab treatment group (n = 70) and golimumab treatment group (n = 68) were as follows: in all patients, -3.5% (90% confidence interval [90% CI] -16.8, 9.8), -8.6% (90% CI -22.0, 4.8), and -9.8% (90% CI -21.1, 1.4), respectively; in the anti-TNF-IR group, 11.1% (90% CI -7.8, 29.9), -8.7% (90% CI -28.1, 10.7), and -0.7% (90% CI -18.0, 16.7), respectively. Differences in the percentage of patients achieving a DAS28-CRP of <2.6 at week 24 between the mavrilimumab and golimumab groups were -11.6% (90% CI -23.2, 0.0) in all patients, and -4.0% (90% CI -20.9, 12.9) in the anti-TNF-IR group. The percentage of patients achieving a >0.22 improvement in the HAQ DI score at week 24 was similar between the treatment groups. Treatment-emergent adverse events were reported in 51.4% of mavrilimumab-treated patients and 42.6% of golimumab-treated patients. No deaths were reported, and no specific safety signals were identified. CONCLUSION: The findings of this study demonstrate the clinical efficacy of both treatments, mavrilimumab at a dosage of 100 mg every other week and golimumab at a dosage of 50 mg every 4 weeks, in patients with RA. Both regimens were well-tolerated in patients who had shown an inadequate response to DMARDs and/or other anti-TNF agents.