FDA Accepts Tildrakizumab sBLA for Expansion Into Psoriatic Arthritis

The United States (US) Food and Drug Administration (FDA) has accepted for review a supplemental biologics license application (sBLA) from Sun Pharmaceutical Industries seeking approval of tildrakizumab (ILUMYA) for the treatment of adults with active psoriatic arthritis (PsA), with a Prescription Drug User Fee Act (PDUFA) date of October 29, 2026.¹

If approved, tildrakizumab would become the latest IL-23 inhibitor to gain a PsA indication — joining risankizumab (Skyrizi; AbbVie) and guselkumab (Tremfya; Johnson & Johnson) — and would represent a meaningful cross-specialty expansion for a biologic that has been used primarily in dermatology since its FDA approval for moderate-to-severe plaque psoriasis in 2018.¹

"For many people living with psoriatic disease, joint symptoms often add another layer of burden," Rick Ascroft, CEO, Sun Pharma North America, said in a statement.¹ "As we continue to strengthen Sun Pharma's innovative portfolio, we look forward to working with the FDA throughout the review process. As the only HCP-administered IL-23 biologic, our ambition is that ILUMYA becomes a differentiated first-choice advanced systemic treatment for active psoriatic arthritis."

The INSPIRE Program

The sBLA is supported by data from 2 phase 3 pivotal trials, INSPIRE-1 (NCT04314544) and INSPIRE-2 (NCT04314531), which together enrolled more than 800 adults with active PsA at clinical sites across the US, Europe, and Asia.¹ Both are 52-week, multicenter, randomized, double-blind, placebo-controlled studies evaluating tildrakizumab 100 mg in adults with active PsA.

The 2 trials were designed to capture distinct treatment-history populations: INSPIRE-1 enrolled patients with prior exposure to an anti-TNF agent, while INSPIRE-2 enrolled anti-TNF-naïve patients. In both studies, tildrakizumab was administered as a single dose at week 0 and then every 12 weeks thereafter — notably without an induction dose at week 4, a departure from the dosing schedule used in the drug's pivotal plaque psoriasis trials.²

Both studies met their primary endpoint. A significantly greater proportion of tildrakizumab-treated patients achieved an ACR20 response at week 24 compared with placebo (P <.05 in both trials).² ACR20, a composite measure requiring at least 20% improvement in tender and swollen joint counts alongside improvement across several patient-reported measures, is the standard regulatory threshold in PsA trials. Full efficacy and safety data from both studies have not yet been presented at a scientific congress or published in a peer-reviewed journal; Sun Pharma has indicated those data will be shared at a future meeting.¹

Supportive long-term safety data were presented at ACR Convergence 2025 from an open-label extension of tildrakizumab's phase 2b PsA trial (NCT02980692). Among 281 patients followed through week 208, adverse events were consistent with prior findings, most were mild or moderate, and no new safety signals were identified. Treatment-related serious adverse events occurred in 0.7% of participants, and the incidence of antidrug antibodies was low and not associated with safety concerns.³

The Competitive PsA Field

Tildrakizumab's entry into PsA review arrives in an active regulatory environment for the indication. Deucravacitinib (Sotyktu; Bristol Myers Squibb), a TYK2 inhibitor, recently received FDA approval for PsA, and bimekizumab (Bimzelx; UCB) demonstrated superiority over risankizumab in the head-to-head BE BOLD trial — a result that has renewed scrutiny of how IL-23 inhibitors perform relative to other mechanistic classes in this population.

Within the IL-23 inhibitor class, tildrakizumab has mechanistic similarities to risankizumab and guselkumab, all three selectively targeting the p19 subunit of IL-23 to interrupt signaling through the IL-23/Th17 axis. Sun Pharma has positioned tildrakizumab's quarterly maintenance dosing — and its status as the only HCP-administered IL-23 biologic in this class — as potential differentiators in the PsA market.¹

The psoriatic disease link is clinically relevant here. Roughly 1 in 3 patients with psoriasis will develop PsA, often with years of delay between skin and joint diagnosis, and more than 15% of psoriasis patients may have undiagnosed PsA at any given time.¹ Tildrakizumab has supported approximately 140,000 patients with plaque psoriasis worldwide, with real-world data demonstrating durable response and treatment persistence through 5 years of follow-up — a clinical track record that may ease prescriber familiarity if the PsA indication is granted.¹

Sun Pharma will present full INSPIRE trial data at a medical congress, likely ahead of the potential decision.

References

1. Sun Pharma Announces US FDA Acceptance of Supplemental Biologics License (sBLA) Application for ILUMYA® (tildrakizumab-asmn) for the Treatment of Adults with Active Psoriatic Arthritis. News release. Sun Pharmaceutical Industries. March 16, 2026. https://www.prnewswire.com/news-releases/sun-pharma-announces-us-fda-acceptance-of-supplemental-biologics-license-sbla-application-for-ilumya-tildrakizumab-asmn-for-the-treatment-of-adults-with-active-psoriatic-arthritis-302714083.html

2. Sun Pharma's Phase 3 Clinical Studies Evaluating Tildrakizumab 100 mg (ILUMYA®) in Active Psoriatic Arthritis Meet their Primary Endpoint. News release. Sun Pharmaceutical Industries. July 21, 2025. https://sunpharma.com/wp-content/uploads/2025/07/Press-Release-Phase-3-Clinical-Studies-PsA-ILUMYA-Topline.pdf

3. Mease PJ, Chohan S, Fructuoso FJG, et al. Long-term safety of tildrakizumab through week 208 in patients with psoriatic arthritis: Results from the phase 2b open-label extension study. Poster presented at: ACR Convergence 2025; October 24–29, 2025; Chicago, IL.

4. Villani AP, Rouzaud M, Sevrain M, et al. Prevalence of undiagnosed psoriatic arthritis among psoriasis patients: Systematic review and meta-analysis. J Am Acad Dermatol. 2015;73(2):242-248. doi:10.1016/j.jaad.2015.05.002