The Phase 2a trial, which enrolled 33 participants with severe or very severe alopecia, tracked patients over a 36-week treatment period followed by a 16-week off-drug observation phase. By the end of the study, 44% of patients achieved a SALT-20 response—a key measure of scalp hair coverage. Notably, participants who showed hair growth during the treatment phase maintained or deepened their response during the subsequent off-drug period, with mean SALT scores remaining stable.

Biomarker analysis and post-treatment biopsies provided further evidence of the drug's mechanism, showing reduced inflammation around hair follicles and lower levels of T-cell-related cytokines. The treatment was generally well-tolerated, with injection site reactions being the most common adverse event and no new safety signals reported. These findings are particularly significant given that 36.4% of the trial participants had previously failed to see results with oral JAK inhibitors.

Q32 Bio plans to utilize these results to initiate a registration-directed program in the first half of 2027. The company is currently evaluating the potential for less frequent, chronic maintenance dosing, which could address a major gap in current dermatological care.