THURSDAY, May 18, 2023 (HealthDay News) -- For patients with moderately to severely active psoriatic arthritis, the tyrosine kinase 2/Janus kinase 1 inhibitor brepocitinib is effective for reducing symptoms, according to a study published online May 17 in Arthritis & Rheumatology.

Philip Mease, M.D., from the University of Washington in Seattle, and colleagues conducted a placebo-controlled trial involving participants with moderately to severely active psoriatic arthritis. Two hundred eighteen participants were randomly assigned to brepocitinib 10 mg once daily (QD), 30 mg QD, 60 mg QD, or placebo, advancing to brepocitinib 30 or 60 mg QD at week 16.

The researchers found that brepocitinib 30 and 60 mg QD groups had significantly greater American College of Rheumatology (ACR)20 response rates at week 16 versus placebo (66.7 and 74.6 percent, respectively, versus 43.3 percent) and had significantly higher ACR50/70, 75 percent and 90 percent improvement in Psoriasis Area and Severity Index, and Minimal Disease Activity response rates. Through week 52, response rates were maintained or improved. Adverse events were mostly mild/moderate; in 12 participants, serious adverse events occurred, including infections in six participants in the brepocitinib 30- and 60-mg QD groups. There were no major adverse cardiovascular events or deaths reported.

"These data demonstrate striking efficacy and confirm the relevance of multiple signaling pathways dependent on the kinases targeted by brepocitinib in psoriatic arthritis," Mease said in a statement. "The safety is also reassuring for brepocitinib in this study."

Several authors disclosed financial ties to pharmaceutical companies, including Pfizer, which manufactures brepocitinib and funded the study.