Tildrakizumab Improves Signs, Symptoms of Active Psoriatic Arthritis in Phase 3 Studies

Tildrakizumab 100 mg (Ilumya; Sun Pharmaceuticals) demonstrated greater improvements in the signs and symptoms of psoriatic arthritis (PsA) at week 24 compared with placebo in the INSPIRE-1 and INSPIRE-2 studies. The results, which were released in a news release from Sun Pharmaceuticals, showcase the humanized immunoglobulin G1 (IgG1)/k monoclonal antibody's potential in the treatment of PsA.¹

Psoriatic arthritis can lead to a litany of inflammatory complications. | Image Credit: © Premium Graphics - stock.adobe.com

Background on Tildrakizumab and the INSPIRE Trials

An IL-23 agonist, tildrakizumab selectively binds to IL-23 to inhibit its interaction with the IL-23 receptor and downstream signaling, blocking the release of pro-inflammatory cytokines and chemokines. It was previously approved by the FDA in 2018 for the treatment of adults with moderate-to-severe plaque psoriasis. The INSPIRE studies, which are 52-week, global, multicenter, randomized, double-blind, single-dose, placebo-controlled phase 3 studies, were designed to assess the safety and efficacy in a similar population, one with active PsA.^1-3

In INSPIRE-1, patients were enrolled following prior exposure to an anti-tumor necrosis factor (TNF) medication, while patients enrolled in INSPIRE-2 were anti-TNF–naïve. Over 800 adults were enrolled in the 2 studies and were randomized to receive either a 100-mg dose of tildrakizumab or a placebo. Contrasting with other phase 3 studies that evaluated the agent in plaque psoriasis—which dosed patients at weeks 0 and 4, and then every 12 weeks—investigators dosed patients once at week 0 and then every 12 weeks.¹

In both studies, the primary end point was the proportion of participants achieving an ACR20 response at week 24. ACR20 is a composite measure, defined as a 20% improvement in both the number of tender and swollen joints and a 20% improvement in a series of criteria, including patient global assessment, visual analog pain scale, and functional ability measure.¹

Primary End Point of PsA Improvement Successfully Achieved in INSPIRE Trials

Results from both studies indicated that the primary end point was met, with a higher proportion of patients in the INSPIRE-1 and INSPIRE-2 studies treated with tildrakizumab achieving ACR20 responses at week 24 compared with patients receiving placebo (P < .05). Furthermore, garnered safety data was aligned with previously documented safety profiles of tildrakizumab, and no new safety signals were identified by the investigators.¹

The detailed findings from the INSPIRE studies will be presented at a series of upcoming medical conferences and published in a peer-reviewed journal, according to Sun Pharmaceuticals.¹

"We are excited to share that both the INSPIRE-1 and INSPIRE-2 clinical trials have successfully met their primary endpoints. These top-line results reinforce the therapeutic potential of ILUMYA as a treatment option for patients with active psoriatic arthritis,” Marek Honczarenko, MD, PhD, senior vice president and head of global specialty development at Sun Pharma, said in the news release. “We extend our sincere gratitude to the patients, health care professionals, and administrators whose contributions made the studies possible. We look forward to sharing the complete clinical data in the near future.”¹

PsA presents a major burden to patients impacted. As a chronic autoimmune disease, patients with PsA face consistent obstacles to living out their daily lives, as the condition causes swelling, pain, and joint stiffness. PsA can develop at any age and can occur in patients regardless of the severity of underlying psoriasis. Critically, psoriasis and psoriatic arthritis are intrinsically linked, with 1 in 3 people living with psoriasis also living with PsA. Thus, tildrakizumab presents as an especially hopeful option given its prior approval by the FDA for use in treating plaque psoriasis.¹

Given their similar presentations and overlapping etiology, it is essential for pharmacists and patients to have a thorough understanding of the condition and proper treatment and management strategies for each. Tildrakizumab could become a useful agent in the PsA population, building on its already established use in plaque psoriasis and providing treatment providers a novel agent for patients burdened by the condition.¹

As tildrakizumab proceeds through its clinical development pipeline, pharmacists and treatment providers should be on the lookout for newly released data and other indications that the agent is progressing towards FDA regulatory action, which could make it available to consumers in the future.

REFERENCES

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

2. Wang M. Clinical overview: Tildrakizumab-asmn (Ilumya) for Plaque Psoriasis. Pharmacy Times. Published July 18, 2022. Accessed July 23, 2025. https://www.pharmacytimes.com/view/clinical-overview-tildrakizumab-asmn-ilumya-for-plaque-psoriasis

3. Coppock K, Toich L. FDA approves treatment for moderate-to-severe plaque psoriasis. Pharmacy Times. Published March 21, 2018. Accessed July 23, 2025. https://www.pharmacytimes.com/view/fda-approves-treatment-for-moderatetosevere-psoriasis