Q32 Bio Doses First Patients in Both Part A Open-Label Extension & Part B of SIGNAL-AA Phase 2a Trial Evaluating Bempikibart in Alopecia Areata

Q32 Bio Inc. recently announced it has dosed the first patients in both the Part A open-label extension (OLE) and Part B of the SIGNAL-AA Phase 2a clinical trial evaluating bempikibart in patients with alopecia areata (AA).

“Dosing the first patients in both the Part A OLE and Part B of our SIGNAL-AA trial highlights our ongoing momentum in the clinical development of bempikibart as a potential treatment for AA,” said Jodie Morrison, Chief Executive Officer of Q32 Bio. “Based upon the encouraging clinical activity observed to date, including patients with continued responses in long-term follow-up months after completing treatment, robust pharmacologic data and a well-tolerated safety profile, we believe bempikibart has the potential to transform the AA treatment paradigm as a new and differentiated therapy for patients, if approved.”

Q32 previously announced results from Part A of the SIGNAL-AA Phase 2a clinical trial, a randomized, double-blind, placebo-controlled, multi-center clinical trial evaluating bempikibart in adult patients with severe and very severe AA (baseline Severity of Alopecia Tool (SALT) scores of 50-100) treated over 24 weeks, with follow-up through 36 weeks. Results reported to date have demonstrated encouraging clinical activity, including improvement from baseline on SALT score and meaningful achievement of SALT-20 (SALT score less than or equal to 20) response through week 36. Part A of the SIGNAL-AA clinical trial has been completed. Through additional post-clinical trial data collection after 36 weeks, continued responses were observed in multiple patients through week 55, approximately seven months post last dose, along with continued SALT reductions in some patients, despite dosing through only 24 weeks. The Company believes these findings may be suggestive of a remittive effect, durability of response, and a key differentiation from currently approved therapies. Based on re-consent rates and strong patient demand for continued dosing, Q32 Bio initiated the OLE for eligible patients that completed Part A to enable longer-term follow-up of patients.

Part B of the SIGNAL-AA Phase 2a clinical trial is an open-label clinical trial, dosing approximately 20 evaluable severe or very severe AA patients with bempikibart for 36 weeks, with follow-up out to 52 weeks. Dosing will include an initial loading regimen of 200mg of bempikibart dosed weekly over four weeks, followed by a maintenance dose of 200mg every-other-week over a 32-week period for a total dosing period of 36 weeks. Efficacy will be evaluated on the basis of mean percentage change from baseline in SALT scores as well as the proportion of subjects achieving various relative and absolute SALT improvements at week 36, with follow-up through week 52. The trial is intended to support advancement into pivotal trials upon completion, pending review of the results. Q32 Bio expects to report topline data from SIGNAL-AA Part B in the first half of 2026.

Q32 Bio is a clinical-stage biotechnology company whose science targets potent regulators of the adaptive immune system to re-balance immunity and is focused on developing innovative therapies for alopecia areata and other autoimmune and inflammatory diseases. About 700,000 people in the United States live with alopecia areata¹, a disease which has a life-altering impact on patients and limited current treatment options. The Company is advancing bempikibart (ADX-914), a fully human anti-IL-7Rα antibody that re-regulates adaptive immune function, for the treatment of alopecia areata in an ongoing Phase 2 program. The IL-7 and TSLP pathways have been genetically and biologically implicated in driving several T cell-mediated pathological processes in numerous autoimmune diseases. For more information, visit www.Q32Bio.com.

1. National Alopecia Areata Foundation

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