Bempikibart - (SIGNAL-AA)

July 13, 2026: Q32 Bio Inc. (NASDAQ: QTTB) reported positive 36-week topline results from Part B of the open-label SIGNAL-AA Phase 2a trial of bempikibart (ADX-914), a fully human anti-IL-7Rα antibody, in 33 patients with severe/very severe alopecia areata (baseline SALT 50–100). The prespecified primary endpoint (mean % change from baseline SALT in the mITT population) showed a 35.3% mean SALT reduction at Week 36. At Week 36, SALT-20 response was 40.0% (10/25) in mITT and 30.3% (10/33) in ITT; SALT30 response was 44.0% (11/25) mITT and 33.3% (11/33) ITT; SALT50 response was 44.0% (11/25) mITT and 33.3% (11/33) ITT. Prior oral JAK inhibitor exposure was allowed; 36.4% had been previously treated.

Safety was generally well tolerated with no new safety signals; no treatment-related SAEs or Grade ≥3 AEs. Most common AE was mild injection site reactions (36.3%). PK/PD and anti-drug antibody profile was favorable with negligible ADA. Week 52 off-drug follow-up and open-label extension enrollment are ongoing. The company plans to advance a registration-directed program in 1H 2027 and present full Part B results at a future medical meeting. A conference call/webcast was scheduled for July 13, 2026 at 8:00 a.m. ET.