Dazukibart Effective in Adults with Dermatomyositis

Jack Cush, MD

Jan 13, 2025 7:08 pm

Lancet reports that the use of dazukibart, a selective monoclonal antibody against interferon B (IFNβ), was clinically effective in reducing disease activity in adults with active dermatomyositis (DM).

Dermatomyositis is a chronic autoimmune disease whose pathophysiology involves type I interferon (IFN) dysregulation.

A multicentre, double-blind, randomised, placebo-controlled, phase 2 trial enrolled adults with moderate-to-severe skin-predominant DM. Patients were assessed using the Cutaneous Dermatomyositis Disease Area and Severity Index-Activity (CDASI-A. Patients were treated with placebo or dazukibart 600 mg, dazukibart 150 mg, or placebo at different stages of investigation. Therapy was administered intravenously on day 1 every 4 weeks, up to and including week 8 or on week 12 every 4 weeks, up to and including week 20. The primary outcome was the change from baseline in CDASI-A score at week 12.

A total of 75 DM patients were randomized (15 to dazukibart 150 mg, 37 to dazukibart 600 mg, and 23 to placebo). Most were female (93%)in the skin-predominant cohort vs 72% in the 18 patients with muscle-predominant DM.

At week 12, the mean CDASI-A change:

In the Full Cohort - dazukibart 600 mg was –18·8 (placebo-adjusted difference –14·8 [–20·3 to –9·4]; p<0·0001).
In the skin cohort - dazukibart 600 mg –19·2 (placebo-adjusted difference –16·3 [–20·4 to –12·1]; p<0·0001)
- dazukibart 150 mg group was –16·6 (placebo-adjusted difference –13·7 [–18·3 to –9·0]; p<0·0001).

Adverse events were similar between groups with infections and infestations most common. Serious adverse events were seen in 4 (11%) dazukibart 150 mg group and 1 (4%) placebo group. One patien (dazukibart 600 mg) died during follow-up due to haemophagocytic lymphohistiocytosis and macrophage activation syndrome.