Takeda's Zasocitinib Meets Phase 3 Endpoints in Plaque Psoriasis, Pediatric Trial Underway

Takeda announced positive topline results for two pivotal Phase 3 randomized, multicenter, double-blind, placebo- and active comparator-controlled studies of zasocitinib (TAK-279), a next-generation, highly selective oral tyrosine kinase 2 (TYK2) inhibitor, in adults with moderate-to-severe plaque psoriasis. The studies demonstrated superiority of zasocitinib compared to placebo for the co-primary endpoints, static Physician Global Assessment (sPGA) 0/1 and Psoriasis Area and Severity Index (PASI) 75, at week 16.

A significantly greater PASI 75 response rate was seen as early as week 4 and continued to increase through week 24. The studies also met all 44 ranked secondary endpoints, including PASI 90, PASI 100 and sPGA 0 against placebo and apremilast, showing the potential of a convenient once-daily pill to deliver complete skin clearance for patients with plaque psoriasis.

More than half of patients treated with zasocitinib achieved clear or almost clear skin (PASI 90) and about 30 percent achieved completely clear skin (PASI 100) at week 16, with response rates continuing to increase through week 24. The CEO stated that this marks the third positive Phase 3 readout from the overarching pipeline this year, with each program having potential to transform patient lives, redefine medical practice and deliver significant revenue growth in the future.

Zasocitinib was generally well-tolerated. The safety and tolerability profile of zasocitinib in the Phase 3 studies remained consistent with prior studies, including the Phase 2b plaque psoriasis study. The most common adverse events through week 24 were upper respiratory tract infection, nasopharyngitis and acne, with no new safety signals identified.

Takeda intends to present the results at upcoming medical congresses and plans to submit a New Drug Application with the United States Food and Drug Administration and other regulatory authorities starting in fiscal year 2026. Results from the Phase 3 studies have no significant impact on the full-year consolidated forecast for the fiscal year ending March 31, 2026.

Zasocitinib is also being evaluated in a head-to-head study against deucravacitinib in plaque psoriasis, Phase 3 studies in psoriatic arthritis and Phase 2 studies in Crohn's disease and ulcerative colitis, among other indications.

Separately, Takeda is running a Phase 3 trial to test zasocitinib in children and teens with moderate to severe plaque psoriasis. The study aims to see how well the drug clears skin, how safe it is over time, and how younger patients respond, which could support a key label expansion if results are positive. The trial is interventional and randomized, with patients split into groups that receive either zasocitinib or placebo at first. It uses a double-blind design in part of the study so neither doctors nor participants know who gets the active drug, and then moves to open-label treatment to track longer term benefits and risks. The trial was first submitted in November 2025, with the latest update hitting the registry in February 2026.

Zasocitinib is an investigational, next-generation, highly selective oral TYK2 inhibitor that maintains 24-hour inhibition of IL-23 plus other core disease-driving immune pathways. It has more than 1-million-fold greater selectivity for TYK2 compared to other JAK enzymes, which could maximize TYK2 inhibition without impacting JAK1, 2 and 3 signaling, based on in vitro data.

Psoriasis is a chronic immune-mediated inflammatory disease in which the body's immune system causes inflammation which results in skin cells that multiply too quickly. Plaque psoriasis, the most common form of psoriasis, is characterized by raised, red, gray or purple patches of skin that are itchy, painful and covered by scales. Globally, an estimated 64 million people are living with psoriasis and about 80-90% of those have plaque psoriasis.