311 Treatment of bullous pemphigoid by inhibiting fcrn: Pre-registration report of a phase 2/3 trial with efgartigimod

Bullous pemphigoid (BP) is an autoimmune blistering disease, characterized by subepidermal blisters and mediated IgG autoantibodies against BP180 (type XVII collagen) BP230 structural proteins of the dermal-epidermal junction. Efgartigimod, engineered Fc fragment, inhibits FcRn activity, thereby decreasing serum autoantibodies. This pre-registration report describes a Phase 2/3 randomized, double-blind, placebo-controlled trial efgartigimod in patients with moderate to severe (by PDAI) BP. In Part A (proof concept, phase 2), 40 participants will be recruited, while B (confirmatory, 3) 120 recruited. are identical schedule, structure, assessments, conduct. 2000 mg PH20 SC (as two 1000 injections) given on days 1 (baseline) 8 (week 1), administered weekly through week 35. The primary endpoint proportion who have been complete remission receiving minimal oral corticosteroid therapy for ≥8 weeks at 26.