KT-621 - (BREADTH)

June 12, 2026: Kymera Therapeutics, Inc. (NASDAQ: KYMR) presented new Phase 1 data for KT-621, its first-in-class oral STAT6 degrader, in healthy Japanese adults at the Japanese Dermatological Association (JDA) Annual Meeting (Kyoto; June 11–14, 2026). The randomized, double-blind, placebo-controlled study enrolled 24 healthy Japanese adults across two dose levels (3:1 KT-621:placebo) dosed once daily for seven days to support regulatory requirements ahead of enrolling Japanese patients into global Phase 2b trials.

KT-621 showed rapid absorption, dose-proportional plasma exposure, and rapid, sustained STAT6 degradation in blood, with median degradation ≥98% at both dose levels at Day 7. The drug was reported as well tolerated with a favorable safety profile; results were described as comparable to prior Phase 1 findings in non-Japanese adults and atopic dermatitis patients.

Ongoing catalysts: parallel Phase 2b trials are ongoing—BROADEN2 in atopic dermatitis (data expected mid-2027) and BREADTH in asthma (data expected late 2027)—intended to support subsequent parallel Phase 3 registration studies.