Q32 Bio Inc. is restructuring to focus on the advancement of its bempikibart clinical development program for the treatment of patients with alopecia areata (AA).
“We have conviction that bempikibart is differentiated from existing AA therapies and has the potential to transform the treatment paradigm for this disease. This is based on the continued emergence of bempikibart data in alopecia areata patients with longer-term follow-up from Part A of the SIGNAL-AA Phase 2a clinical trial, the robust pharmacologic data, and a well-tolerated safety profile,” says Jodie Morrison, Chief Executive Officer of Q32 Bio, in a news release. “Further, based on the clinical characteristics of bempikibart, we continue to believe there is potential utility across additional autoimmune conditions. Our immediate next steps will be to extend dosing of eligible patients from SIGNAL-AA Part A in an open-label extension arm and to initiate dosing of patients in the SIGNAL-AA Part B clinical trial in the first half of 2025, with Part B topline data expected in the first half of 2026.”
Results observed to date from Part A of the SIGNAL-AA Phase 2a clinical trial of bempikibart in patients with AA demonstrated encouraging clinical activity, including improvement from baseline on Severity of Alopecia Tool (SALT) score and meaningful achievement of SALT-20 (SALT score less than or equal to 20) response through week 36, and continued response in multiple patients through week 55, approximately 7 months post last dose. Results from this longer-term follow-up show continued mean SALT reductions, despite dosing through only 24 weeks, which may be suggestive of a remittive effect, durability of response, and a key differentiation from currently approved therapies. Across clinical trials, including SIGNAL-AA, bempikibart was observed to be well-tolerated, with robust pharmacologic activity through desired target engagement, as demonstrated by receptor occupancy, robust changes in T helper 2 (Th2)biomarkers, and expected changes in T-cells, indicative of potent interleukin (IL)-7 and thymic stromal lymphopoietin (TSLP) inhibition.
Data continues to be collected from a group of patients who re-consented to the trial, with patient data available through 55 weeks and longer follow-up expected. Based on re-consent rates and strong patient demand for continued dosing, Q32 Bio is initiating an open-label extension (OLE) following the same bempikibart dosing regimen leveraged in Part A to enable longer-term follow-up of patients.
In addition to the initiation of the OLE, Q32 Bio expects to initiate dosing in SIGNAL-AA Part B in the first half of 2025.
SIGNAL-AA Part B is an open-label clinical trial, dosing patients with bempikibart for 36 weeks, with follow-up out to 52 weeks, in approximately 20 evaluable patients with severe or very severe AA. 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 of 36 weeks. The primary efficacy endpoints include the proportion of patients achieving a 30% or greater reduction in SALT score and proportion of patients achieving a SALT-20 at week 36, with follow-up through week 52. The trial is intended to enable advancement into pivotal trials upon completion, pending review of the results. Q32 Bio expects to report initial data from SIGNAL-AA Part B in the first half of 2026.
As part of the restructuring, the Company is discontinuing the Phase 2 renal basket clinical trial of ADX-097 and is evaluating strategic options for its tissue-targeted complement inhibitor platform, inclusive of ADX-097 and early-stage assets. In combination with other cost-saving measures including a reduction in personnel and related expenses, the strategic restructuring is expected to extend cash runway to the second half of 2026.
