Zasocitinib Demonstrates Biologic-Level Efficacy in Psoriasis

Key Takeaways

• Zasocitinib demonstrated high rates of skin clearance, outperforming both placebo and apremilast in two Phase 3 trials.
• Rapid onset of action was observed, with clinically meaningful responses as early as Week 4.
• Oral TYK2 inhibition may approach biologic-level efficacy, potentially shifting treatment paradigms in psoriasis.

Zasocitinib, a selective oral tyrosine kinase 2 (TYK2) inhibitor, demonstrated rapid and robust efficacy with a consistent safety profile in moderate-to-severe plaque psoriasis, according to Phase 3 LATITUDE-PsO-3001 and LATITUDE-PsO-3002 trial results presented by Melinda Gooderham, MD, MSc, at the American Academy of Dermatology (AAD) 2026 Annual Meeting.

Across the two randomized, double-blind trials enrolling more than 1,800 patients, once-daily zasocitinib met co-primary endpoints at Week 16, with significantly higher rates of sPGA 0/1 (71.4%/69.2% vs 10.7%/12.6%; P < .001) and PASI-75 (75.7%/71.4% vs 12.1%/12.3%; P < .001) compared with placebo. Zasocitinib also demonstrated superiority over apremilast across key endpoints.

Higher-level skin clearance was achieved by Week 24, with PASI-90 responses of 69.0%/62.7% and PASI-100 responses of 42.3%/32.1% with zasocitinib, compared with substantially lower rates with apremilast (all P < .001). Improvements were observed early, with PASI-75 superiority versus placebo evident by Week 4.

Dr. Gooderham emphasized the clinical implications of these findings, noting that oral TYK2 inhibition may close the efficacy gap with biologics.

“Zasocitinib sort of takes us to the next level with higher selectivity, potency, and ability to give us skin clearance equivalent to some of our biologics,” she said. 

Rapid onset of action was also highlighted.

“Seventeen percent of patients even achieved a PASI-75 at Week 4,” Dr. Gooderham said, adding that this could impact adherence and patient satisfaction. 

Durability of response was supported by withdrawal data, with some patients maintaining disease control for up to 20 weeks after discontinuation.

Safety findings were consistent with prior studies. Treatment-emergent adverse events were generally mild to moderate, with upper respiratory tract infection, nasopharyngitis, and acne among the most common. No new safety signals were identified.

Looking ahead, Dr. Gooderham noted that long-term data will be important for broader adoption, particularly as oral therapies move closer to biologic-level performance.

“We always need long-term safety and long-term efficacy,” she said.