A Phase 3, Multi-Center, Open-Label Extension Study to Investigate the Long-Term Safety, Tolerability, and Efficacy of Dazukibart in Participants With Idiopathic Inflammatory Myopathies (Including Dermatomyositis or Polymyositis)

What this Trial Is About

Researchers are studying how the medicine dazukibart works in people with active idiopathic inflammatory myopathies, specifically dermatomyositis (DM) or polymyositis (PM). These conditions cause inflammation and weakness in muscles near the body’s center, affecting activities like climbing stairs or lifting objects. DM also involves a skin rash, and these disorders can impact lung and heart function, reducing quality of life. This trial is designed as a Phase 3, multi-center, open-label extension to assess long-term safety, tolerability, and effects of dazukibart. Participants who took part in a prior dazukibart study and completed up to Week 52 may join this extension. Those receiving dazukibart will get an intravenous (IV) infusion lasting about one hour every 4 weeks for up to 48 weeks (about 12 months). After the treatment period, there is a safety follow-up lasting about 4 months. Participants who choose not to receive the study medicine or are ineligible will only participate in safety follow-up visits, which happen every 4 weeks for up to 4 visits. During the study, participants receiving dazukibart will attend about 18 visits over roughly 16 months, while those on safety follow-up alone will have up to 4 visits. The trial monitors treatment-emergent side effects, lab and vital sign changes, lung function (Forced Vital Capacity and lung gas exchange), and mental health using the Columbia-Suicide Severity Rating Scale. Secondary measures include muscle strength, disease activity assessments, patient-reported physical function, fatigue, quality of life, and medication use. This comprehensive monitoring helps evaluate the long-term impact of dazukibart in managing idiopathic inflammatory myopathies.

A Study to Understand How the Study Medicine Dazukibart Works in People With Idiopathic Inflammatory Myopathies