Q32 Bio (QTTB) Wells Fargo 21st Annual Healthcare Conference summary

Program highlights and clinical data

• Positive readout from Part B of the SIGNAL-AA program demonstrated JAK-like efficacy, with 30% and 40% SALT20 response rates in ITT and mITT populations, respectively.

• Both ITT and mITT data sets were strong, with careful exclusion criteria applied to ensure data integrity, including patient stability and dosing adherence.

• Safety profile remains favorable, with low rates of mild injection site reactions and no discontinuations due to adverse events or lymphocyte reductions.

• Durability of response is being evaluated, including off-drug periods and open-label extensions to assess long-term effects and late responders.

• Additional biomarker and biopsy data, as well as 52-week durability results, are expected at upcoming conferences.

Regulatory and trial design strategy

• Plans to move into a registration program for alopecia areata, with a phase III trial anticipated to use a 36-week primary endpoint and dosing through 52 weeks.

• Key regulatory questions include adolescent inclusion, single phase III approval, dose ranging requirements, and safety database size.

• Conservative placebo response estimates and trial overpowering are planned to ensure robust results and regulatory success.

• Guidance on phase III design and timelines will be provided after the end of phase II FDA meeting, expected by year-end or early next year.

Commercial and competitive landscape

• Efficacy matches or exceeds approved JAK inhibitors, but commercial opportunity is driven by demand for a safe biologic alternative.

• Market analysis suggests most patients and physicians prefer biologics over JAKs due to long-term safety concerns.

• The product is positioned to potentially become the first-line therapy, similar to DUPIXENT in atopic dermatitis.

• Speed of onset is less critical than safety and durability for chronic conditions like alopecia areata.