FDA greenlights Ilumya for psoriatic arthritis, expanding its reach beyond psoriasis

The FDA has approved tildrakizumab-asmn (Ilumya, Sun Pharmaceutical Industries) for adults with active psoriatic arthritis, adding a new indication to the IL-23 inhibitor that's been on the market for moderate-to-severe plaque psoriasis since 2018. The drug is given as a 100 mg subcutaneous injection at weeks 0 and 4, then every 12 weeks — and unlike many biologics, it's administered by a healthcare provider rather than self-injected.

The approval is based on results from the INSPIRE-1 and INSPIRE-2 global phase 3 trials, both of which showed tildrakizumab outperformed placebo on the primary endpoint of ACR20 response at 24 weeks. The safety profile was consistent with prior studies, with side effects like plaque psoriasis flares, upper respiratory infections, injection site reactions, and diarrhea each occurring in fewer than 5% of participants.

Key Takeaways:

• Tildrakizumab achieved ACR20 response superiority over placebo at 24 weeks in both INSPIRE-1 and INSPIRE-2
• The HCP-administered dosing schedule (not self-injectable) may benefit patients who struggle with self-administration or who benefit from regular clinical touchpoints
• Side effects were mild and occurred in less than 5% of patients

Why it matters: Psoriatic arthritis is a chronic, complex condition that often requires individualized treatment. Adding an IL-23 inhibitor to the toolkit — especially one with a provider-administered model — gives rheumatologists a new way to tailor care and maintain patient engagement.