Johnson & Johnson reports positive Phase 4 results for Tremfya

Johnson & Johnson announced on September 25, 2026, that Tremfya met its primary and major secondary endpoints in the Phase 4 STAR study. The trial evaluated biologic-naïve adults with active psoriatic arthritis and axial involvement confirmed by magnetic resonance imaging (MRI).

In the study, Tremfya achieved significant improvement in the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score at Week 24 compared to placebo. It also met major secondary endpoints, showing reductions in axial symptoms measured by ASDAS-CRP and objective MRI inflammation of the sacroiliac joints, with no new safety signals identified.

The STAR study enrolled 411 participants worldwide across a 24-week placebo-controlled phase followed by a 24-week active treatment period. Axial involvement affects an estimated 5% to 28% of patients with early psoriatic arthritis and 25% to 70% of those with longer-standing disease.

Johnson & Johnson stated that detailed efficacy and safety data from the trial will be presented at an upcoming scientific congress.