A randomized, phase IIa treatment delayed-start trial of the oral JAK 1/2 inhibitor, baricitinib, in adult idiopathic inflammatory myopathy

The study evaluated the efficacy of 24 weeks of treatment with baricitinib, a JAK1/2 inhibitor, in adult patients with idiopathic inflammatory myopathy (dermatomyositis or polymyositis). A randomized study enrolled 15 patients with a mean age of 43.2 years, including 13 with dermatomyositis and 2 with polymyositis. After 24 weeks of active treatment, all patients achieved minimal improvement (TIS20), 60% achieved moderate improvement (TIS40), and 13% achieved major improvement (TIS60). After 12 weeks of treatment, 73% of patients achieved minimal improvement. Two hospitalizations due to serious adverse events were recorded, but neither was related to the study drug. The study demonstrated the safety and efficacy of baricitinib in patients with idiopathic inflammatory myopathy.