Background Blisibimod, a potent inhibitor of B cell activating factor (BAFF), was evaluated in a Phase 2b clinical trial in patients with SLE.
Objectives To determine the effect of subcutaneous blisibimod on SLE disease activity, including rate of response to the SLE responder index (SRI).
Methods 547 serologically-active SLE patients with baseline SELENA-SLEDAI ≥6 were randomized to receive blisibimod (100mg weekly (QW), 200mg QW, or 200mg Q4W) or placebo in matchin dosing regimens. The primary endpoint was a comparison at Week 24 of the percentage of subjects in the pooled blisibimod and placebo groups who achieved an SRI-5 response (SRI with ≥5 point improvement in SELENA–SLEDAI).
Results The primary endpoint was not met due to the lack of efficacy in the two lower doses. However, SRI-5 response was higher in subjects receiving blisibimod 200mg QW compared with placebo (p=0.02 at Week 20). SRI improvements compared with placebo were higher still in subjects who attained SELENA–SLEDAI improvements of ≥8, and in patients with severe disease (SELENA–SLEDAI≥10 and receiving corticosteroids, n=278, figure 1 ). Despite declining patient numbers, response to blisibimod remained higher than placebo beyond Week 24 while N>30 subjects per cohort. Numerically higher response was also observed with blisibimod in all components of the SRI. Blisibimod was safe and well-tolerated at all dose levels with no meaningful imbalances in serious adverse events or infections compared with placebo.
Conclusions These are the first evidence that SLE disease activity may be improved with subcutaneous injections of a novel biologic therapy.
Disclosure of Interest R. Furie Consultant for: Anthera Pharmaceuticals, M. Scheinberg: None Declared, G. Leon: None Declared, E. Ramiterre: None Declared, M. Thomas: None Declared, A. Chu: None Declared, C. Hislop Employee of: Anthera Pharmaceuticals, R. Martin: None Declared, M. Petri Employee of: Anthera Pharmaceuticals