Efficacy and Safety of Tyrosine Kinase 2/Janus Kinase 1 Inhibitor Brepocitinib for Active Psoriatic Arthritis: A Phase IIb Randomized Controlled Trial

In a phase IIb study, the efficacy and safety of oral brepocitinib, a tyrosine kinase 2/Janus kinase 1 inhibitor, were evaluated in individuals with moderately-to-severely active psoriatic arthritis (PsA) over a period of 52 weeks. The study involved 218 participants who were randomized and treated with brepocitinib at varying doses or a placebo. The primary endpoint, assessed at week 16, was the American College of Rheumatology (ACR)20 response rate. The results showed that brepocitinib at doses of 30 mg and 60 mg once daily demonstrated significantly higher response rates compared to the placebo, with improvements observed in ACR50/70, PASI75/90, and Minimal Disease Activity (MDA) response rates. The adverse events reported were generally mild or moderate, with no major adverse cardiovascular events or deaths recorded. The study concluded that brepocitinib at doses of 30 mg and 60 mg QD effectively reduced signs and symptoms of PsA and exhibited a favorable safety profile.