Sustained Safety Tildrakizumab for Psoriatic Arthritis

The data presented at the American College of Rheumatology Convergence regarding the IL-23 inhibitor tildrakizumab in treating active psoriatic arthritis received expert analysis from Christopher Ritchlin, MD, MPH, professor and chief of the Division of Allergy, Immunology and Rheumatology at the University of Rochester Medical Center.¹

A primary finding from the phase 2b open-label extension study is the confirmation of a favorable safety profile maintained over an extended period of 208 weeks—more than four years. The data, encompassing 281 participants, reported no new safety signals emerged and showed adverse events consistent with prior findings. The safety profile is a major advantage of IL-23 inhibition in psoriatic arthritis, as these agents are not associated with the same significant risk of infections often seen with other biologic treatments. Specifically, the risk of serious infections is lower, and there is no comparable risk of Candida infection that can be observed with IL-17 inhibitors.

While the majority of the study's participants (79.7%) experienced an adverse event, most were mild or moderate. The most common were upper respiratory tract infection and nasopharyngitis. Only 6.0% of patients discontinued treatment due to adverse events. Serious adverse events were infrequent (14.2%), and very few (0.7%) were considered treatment-related. Importantly, rare cardiac disorders and malignancies were not linked to the study drug.

The long-term data also provides information on the sustained effectiveness of tildrakizumab, building on 2 successful Phase 3 trials (INSPIRE-1 and INSPIRE-2) that met their primary endpoint of ACR20 response at 24 weeks. The analysis also addressed broader challenges in clinical trials, particularly the difficulty in confidently demonstrating a clear benefit of new agents over placebo due to high placebo response rates at many sites. Nevertheless, the sustained long-term safety and durability profile of tildrakizumab demonstrated by this data offers compelling evidence supporting its continued development for psoriatic arthritis.