The latest phase 2 readout for Q32 Bio’s alopecia hopeful received a warm reception from investors, backing up the biotech’s claim that the drug could offer a more durable alternative to JAK inhibitors.
The data, released Monday morning, come from part B of the Signal-AA study, which enrolled 33 patients with severe or very severe alopecia areata to receive the anti-IL-7R antibody bempikibart. Patients received a 200-mg subcutaneous dose weekly for four weeks, followed by 200 mg every other week for 32 weeks.
At 36 weeks, 10 patients, or 30.3%, achieved a SALT-20 response, meaning they had 20% or less scalp hair loss and at least 80% scalp hair coverage, according to a July 13 release.
In a prespecified modified intent-to-treat analysis of 25 patients, that proportion rose to 40%. Among this group, the mean reduction in SALT score from baseline was 35.3%, the biotech noted.
Eleven patients, or 33.3% of all 33 enrolled, achieved a SALT-50 response, representing at least a 50% improvement from baseline. The company also pointed to “early signs of durability in the off-drug period,” including patients who maintained or deepened their responses.
There were no serious adverse events or grade 3 or higher adverse events related to treatment. The most common treatment-emergent adverse event was an injection-site reaction, which affected 36.3% of patients. All reactions were mild and resolved without intervention, with most clearing within a day.
Investors rewarded the readout by sending Q32’s shares up sharply Monday. The stock opened at $18.31, about 63% above its Friday closing price of $11.21, and climbed as high as $22.50 during morning trading.
Based on the latest readout, Q32 said it plans to launch a “registration-directed program” for bempikibart in the first half of 2027.
Current options for alopecia areata patients include Eli Lilly and Incyte’s blockbuster JAK inhibitor Olumiant, Pfizer’s Litfulo and Sun Pharma’s Leqselvi. Litfulo is approved for adults and adolescents ages 12 and older, while Olumiant and Leqselvi are approved for adults. A total of 36.4% of the patients in Q32’s trial had previously been treated with oral JAK inhibitors, the biotech noted.
“These results provide important further evidence that our differentiated approach to targeting the biology underlying alopecia areata has the potential to translate into meaningful and durable clinical benefit for patients,” Q32 co-founder and Chief Scientific Officer Shelia Violette, Ph.D., said in the release.
“Despite recent advances, many patients continue to seek treatment options that combine robust efficacy with improved safety and the potential for sustained disease control,” Violette added. “These findings strengthen our confidence in the therapeutic potential of this mechanism and its continued advancement as a differentiated treatment option for patients living with alopecia areata and other autoimmune and inflammatory diseases.”
The thinking behind the asset, which Q32 licensed from Bristol Myers Squibb, is that blocking the IL-7 receptor can reduce signaling involved in the activity and development of immune cells that contribute to autoimmune disease. Bempikibart is designed to block signaling from both IL-7 and thymic stromal lymphopoietin.
Q32 has persevered with bempikibart despite the antibody failing a phase 2 trial in atopic dermatitis at the end of 2024. The setback ultimately led the company to lay off some employees and focus its development efforts on alopecia areata.
That faith appeared to be rewarded last year when the company produced data from part A of the Signal-AA study that Q32 said established proof of concept for bempikibart in alopecia areata.