Zasocitinib Shows Strong Efficacy in Plaque Psoriasis in Phase 3 trials

Two Phase 3 clinical studies evaluated the efficacy and safety of zasocitinib in patients with moderate to severe plaque psoriasis and found promising results. Approximately 70% of participants receiving once-daily oral zasocitinib achieved clear or almost clear skin within 16 weeks, indicating a rapid and meaningful clinical response. The treatment not only showed quick improvement but also demonstrated durable skin clearance over time. Additionally, the safety profile of zasocitinib remained consistent, with no significant new concerns identified.

These findings, presented at the American Academy of Dermatology Annual Meeting, suggest that zasocitinib may represent an effective and well-tolerated oral therapeutic option for patients with moderate to severe plaque psoriasis.

“Our goal in psoriasis treatment is clear or almost clear skin, and previously this has been achieved primarily with injectable therapies,” said Melinda Gooderham, MSc, MD, FRCPC, dermatologist, SKiN Centre for Dermatology, Peterborough, Ontario, Canada, principal investigator for the Latitude PsO studies and presenting author. “These efficacy and safety results show it’s possible for a once-daily pill to deliver rapid, lasting skin clearance, highlighting the potential of zasocitinib to become a leading oral treatment option for plaque psoriasis.”

In the Phase 3 randomized, multicenter, double-blind, placebo- and active comparator-controlled Latitude PsO 3001 and 3002 studies, more than half of patients treated with zasocitinib achieved clear or almost clear skin at week 16, a key measure of treatment success:

• 71.4% and 69.2% of patients treated with zasocitinib achieved a static Physician Global Assessment (sPGA) score of 0/1 versus placebo (10.7% and 12.6%) and apremilast (32.1% and 29.7%) at week 16 (p<0.001).

• 61.3% and 51.9% of patients treated with zasocitinib achieved Psoriasis Area and Severity Index (PASI) 90 versus placebo (5.0% and 4.0%) and apremilast (16.8% and 15.9%) at week 16 (p<0.001).2

Zasocitinib also demonstrated statistically significant improvements in complete skin clearance, an increasingly important treatment goal for patients with plaque psoriasis:

• 39.9% and 33.7% of patients treated with zasocitinib achieved an sPGA score of 0 versus placebo (0.7% and 1.4%) and apremilast (8.0% and 6.5%) at week 16 (p<0.001).

• 33.4% and 25.2% of patients treated with zasocitinib achieved a PASI 100 versus placebo (0.7% and 1.1%) and apremilast (2.9% and 4.3%) at week 16 (p<0.001).

• Responses for co-primary and key secondary endpoints continued to increase through week 24 in both studies.

In Latitude PsO 3002, rapidity of response was demonstrated as early as week 4 versus placebo (PASI 75: 16.8% for zasocitinib vs 4.3% for placebo, p<0.001). Among patients who achieved a PASI 75, PASI 90 or sPGA 0/1 response at week 40 and continued on zasocitinib throughout the study, over 90% maintained their response at week 60.

Zasocitinib was generally well-tolerated. The safety and tolerability profile of zasocitinib in the Phase 3 studies remained consistent with prior studies. Key findings across the two studies include:

• Treatment-emergent adverse events (TEAEs) through week 16 were 62.1% for zasocitinib, 46.9% for placebo and 50.5% for apremilast.

• The most common adverse events for zasocitinib treated patients through week 16 (≥5%) were upper respiratory tract infection (10.1%), nasopharyngitis (6.2%) and acne (6.5%), with no new safety signals identified.

• Serious TEAEs through week 16 were 3.0% for zasocitinib, <1% for placebo and 1.5% for apremilast.

“Our Phase 3 results demonstrate that highly selective TYK2 inhibition can offer many people with moderate-to-severe plaque psoriasis the potential for clear or nearly clear skin,” said Chinwe Ukomadu, MD, PhD, senior vice president and head, Gastrointestinal & Inflammation Therapeutic Area Unit at Takeda. “The positive data also underscore zasocitinib’s potential to deliver rapid and durable results with a favorable safety profile consistent with Phase 2b studies. We are working as quickly as possible with regulators to advance a potential new therapeutic option for patients seeking a safe, effective and convenient oral treatment.”

Takeda is on track 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.