A Phase 3 Trial of Brepocitinib in Dermatomyositis

Brepocitinib is a first-in-class, oral, selective TYK2-JAK1 inhibitor that blocks cytokine signaling, which has been implicated in dermatomyositis.

In this phase 3, double-blind, randomized, placebo-controlled trial, adults with dermatomyositis were assigned in a 1:1:1 ratio to receive once-daily oral brepocitinib at a dose of 30 mg, brepocitinib at a dose of 15 mg, or placebo for 52 weeks. Standard therapies were continued, and glucocorticoids were tapered. The primary end point was the Total Improvement Score, a validated composite myositis index (with scores ranging from 0 to 100 and higher scores indicating greater improvement) at week 52. Key secondary end points, including skin disease activity, glucocorticoid tapering, and physical function, were tested in a multiplicity-controlled sequence.