Hemab Therapeutics recently announced positive results from a Phase 2 clinical study of their investigational subcutaneous therapy sutacimig.
Sutacimig is a laboratory-engineered bispecific antibody being developed as the first-ever prophylactic treatment for individuals with Glanzmann thrombasthenia (GT), one of several diseases the company is looking to ultimately target with this investigational, sub-Q therapy.
GT is an ultra-rare inherited bleeding disorder that is characterized by poorly functioning platelets due to a particular protein deficiency, which results in inadequate clotting and greater susceptibility to prolonged bleeding. People with GT may experience mild-to-severe bleeding symptoms, some of which can be life threatening if not promptly treated.
Existing therapies used to treat bleeding associated with GT include antifibrinolytics, platelet transfusions, and recombinant factor VIIa. While these therapies are primarily used to treat bleeding events as they arise, sutacimig has been developed as a preventive therapy. It binds, stabilizes, and “recruits” the important coagulation protein FVlla to the site of activated platelets at the location of a vascular injury to form a hemostatic plug. This essentially compensates for the body's inability to form healthy clots.
The phase 2 trial evaluated prophylactic treatment with sutacimig in GT patients at varying doses. The results showed an overall 50% decrease in mean annualized treated bleeding rate (ATBR) across all dosage groups. Patients that were administered weekly doses of the therapy saw an estimated 87% decrease in ATBR. Investigators also noted that levels of efficacy were consistent across all major bleeding sites including the nose, gum/mouth, and gastrointestinal tract. The authors also reported that sutacimig “demonstrated robust activity” against both traumatic and spontaneous bleeding events.
The data was presented at the recently wrapped 67th American Society of Hematology (ASH) Annual Meeting and Exposition, held December 6-9 in Orlando, FL
"What stands out in these results is the reduction of the most severe bleeding events requiring intensive interventions," said Paul Saultier, MD, PhD, Head of the French Platelet Reference Center, APHM Hospital de la Timone. According to Saultier, severe bleeding events will often lead GT patients to the hospital and create the greatest burden. “Combined with the reductions we saw across different bleed types and anatomical locations, these data suggest sutacimig could” provide meaningful benefit for GT patients,” he added.
Hemab Therapeutics also announced plans to advance sutacimig into a Phase 3 clinical study sometime in 2026.
Source: PR Newswire, December 8, 2025
