FDA Approves Tildrakizumab for Adults With Psoriatic Arthritis

The FDA has approved tildrakizumab-asmn (Ilumya; Sun Pharma) for the treatment of adults with active psoriatic arthritis (PsA), expanding the IL-23 inhibitor’s label beyond moderate to severe plaque psoriasis, for which it was approved in 2018. Tildrakizumab is administered exclusively by a health care provider, and it is positioned as an option for patients who are unable to self-administer treatment or may benefit from regular in-office care, a distinction that shapes how pharmacists approach access and site-of-care questions for this agent.¹

Approximately 2.4 million Americans live with PsA, a chronic immune-mediated disease that causes pain, swelling, and stiffness in joints and entheses and can lead to permanent joint damage. Roughly 1 in 3 people with psoriasis also have PsA, and more than 15% of people with psoriasis may have undiagnosed PsA.¹

INSPIRE Trials Supported the Approval

The approval is based on the phase 3 INSPIRE-1 (NCT04314544) and INSPIRE-2 (NCT04314531) trials, which are 52-week, global, multicenter, randomized, double-blind, placebo-controlled studies of tildrakizumab 100 mg. INSPIRE-1 enrolled patients with prior exposure to an antitumor necrosis factor (TNF) agent, whereas INSPIRE-2 enrolled anti–TNF-naive patients. More than 800 adults were enrolled across sites in the US, Europe, and Asia. In the trials, tildrakizumab was given at week 0 and then every 12 weeks, without the week 4 induction dose used in the plaque psoriasis program, and stable concomitant methotrexate or leflunomide was permitted.²

Both trials met their primary end point, the proportion of patients achieving at least 20% improvement in American College of Rheumatology criteria (ACR20) at week 24, after only 2 doses. In INSPIRE-1 (n = 510), 41% of patients receiving tildrakizumab achieved ACR20 vs 25% of those receiving placebo. In INSPIRE-2 (n = 296), the rates were 35% vs 23%, respectively.^1,2,4

"Psoriatic arthritis is a complex and chronic disease," Philip Mease, MD, director of rheumatology research at Swedish Medical Center and Providence St Joseph Health, said in the news release announcing the approval. "Adding an IL-23 inhibitor option that is administered by a health care provider gives us a new way to offer appropriate patients additional support and engagement with their healthcare team."¹

Responses Built Through Week 52 in TNF-Naive Patients

Week 52 results from INSPIRE-2, which are scheduled for presentation at ACR Convergence 2026, suggest responses continued to build with longer treatment. Among patients assigned to tildrakizumab, ACR20 response rose from approximately 34.8% at week 24 to 62.3% at week 52, ACR50 from 22.3% to 33.3%, and ACR70 from 11.2% to 25.2%. Among patients with body surface area involvement of at least 3%, Psoriasis Area and Severity Index 75 response rose from 31.6% to 48.1%. Patients who switched from placebo to tildrakizumab at week 24 reached similar response rates by week 52. Because the week 24 figures used multiple imputation and the week 52 figures are observed-case data, the 2 time points are not directly comparable.³

For pharmacists counseling patients who are starting therapy, the longer-term data may help frame expectations about the time course of joint response.

Safety Consistent With Psoriasis Experience

No new safety signals were identified in either trial. The most common adverse events (AEs) in PsA (≥ 3%) were upper respiratory tract infections and COVID-19. Through week 52 in INSPIRE-2, treatment-emergent AEs occurred in 74.3% of patients receiving continuous tildrakizumab and 76.2% of those who switched from placebo. Serious AEs occurred in approximately 3.4% and 6.8%, respectively, and no deaths were reported.^1,3

Tildrakizumab may increase the risk of infection, and treatment should not be started in patients with a clinically important active infection. Patients should be evaluated for tuberculosis (TB) before initiation, latent TB should be treated before the first dose, and patients should be monitored for active TB during and after treatment. Pharmacists should also confirm that age-appropriate immunizations are considered before therapy begins, and live vaccines should be avoided. If a serious hypersensitivity reaction such as angioedema occurs, tildrakizumab should be discontinued immediately.¹

REFERENCES

1. ILUMYA (tildrakizumab-asmn) approved in the U.S. for the treatment of adults with active psoriatic arthritis. News release. Sun Pharma. October 30, 2026. Accessed November 3, 2026. https://sunpharma.com/wp-content/uploads/2026/10/ILUMYA-PsA-Approval-Press-Release-FINAL.pdf

2. Sun Pharma’s phase 3 clinical studies evaluating tildrakizumab 100 mg (ILUMYA) in active psoriatic arthritis meet their primary endpoint. News release. Sun Pharma. July 21, 2025. Accessed November 3, 2026. https://sunpharma.com/wp-content/uploads/2025/07/Press-Release-Phase-3-Clinical-Studies-PsA-ILUMYA-Topline.pdf

3. Mease P, Nishandar T, Mehta S, Tripathi A, Bapat A, Gottlieb A. Efficacy and safety of tildrakizumab in anti-TNF-naïve patients with active psoriatic arthritis: week 52 results from a phase 3, randomized, double-blind, placebo-controlled trial [abstract]. Arthritis Rheumatol. 2026;78(suppl 9). Accessed November 3, 2026. https://acrabstracts.org/abstract/efficacy-and-safety-of-tildrakizumab-in-anti-tnf-naive-patients-with-active-psoriatic-arthritis-week-52-results-from-a-phase-3-randomized-double-blind-placebo-controlled-trial/

4. Ernst D. FDA expands Ilumya approval to active psoriatic arthritis. Rheumatology Advisor. November 2, 2026. Accessed November 3, 2026. https://www.rheumatologyadvisor.com/news/fda-approves-ilumya-psoriatic-arthritis/