Takeda (TSE:4502/NYSE:TAK) reported that zasocitinib, its investigational oral TYK2 inhibitor, met co-primary endpoints in two Phase III trials in adults with moderate-to-severe plaque psoriasis, with approximately 70% of patients achieving clear or almost clear skin at week 16 — a response rate that places the once-daily pill well above the oral active comparator used in both studies.
Trial specifics
The Latitude PsO 3001 and Latitude PsO 3002 studies are global, randomized, double-blind, placebo- and active comparator-controlled Phase III trials enrolling 693 and 1,108 adults, respectively, with moderate-to-severe plaque psoriasis across 21 countries.
Across both studies, 71.4% and 69.2% of zasocitinib-treated patients achieved a static Physician Global Assessment (sPGA) score of 0/1 at week 16, compared with 10.7% and 12.6% for placebo and 32.1% and 29.7% for apremilast (all p<0.001). PASI 90 rates of 61.3% and 51.9% were observed with zasocitinib versus approximately 16% for apremilast at the same timepoint. In Latitude PsO 3002, a statistically significant PASI 75 separation from placebo was detectable as early as week 4 (16.8% vs 4.3%, p<0.001), and among patients who maintained response through week 40, over 90% retained their response at week 60.
Treatment-emergent adverse events through week 16 were more frequent with zasocitinib (62.1%) than with placebo (46.9%) or apremilast (50.5%), with serious TEAEs in 3.0% of zasocitinib patients versus less than 1% for placebo. The most common events were upper respiratory tract infection (10.1%), acne (6.5%), and nasopharyngitis (6.2%), with no new safety signals identified relative to Phase IIb data.
Zasocitinib lining up BMS's Sotyktu
Zasocitinib allosterically inhibits TYK2 by binding the pseudokinase (JH2) domain, suppressing downstream IL-23 and related cytokine signaling implicated in psoriasis pathogenesis. Takeda claims more than one-million-fold selectivity for TYK2 over JAK1, JAK2, and JAK3 based on in vitro data — a selectivity profile it is positioning as a differentiator from Bristol Myers Squibb's deucravacitinib (Sotyktu), the only currently approved TYK2 inhibitor in plaque psoriasis.