Phase 2 long-term extension results show durable bleed protection and a manageable safety profile; FDA has aligned on a Phase 3 dose and regimen, with the pivotal study set to begin in the second half of 2026
Companion natural history data underscore how little prophylactic treatment reaches patients with these rare bleeding disorders today
CAMBRIDGE, Mass. and COPENHAGEN, Denmark – July 14, 2026 – Hemab Therapeutics (Nasdaq: COAG), a clinical-stage biotechnology company focused on blood coagulation disorders, today announced new clinical and preclinical findings for sutacimig, its lead investigational therapy for Glanzmann thrombasthenia (GT) and Factor VII deficiency (FVIID), at the International Society on Thrombosis and Haemostasis (ISTH) 2026 Congress in Paris.
The data were among nine total company-led presentations at the meeting, which also included new results for HMB-002 in Von Willebrand disease and the introduction of the HMB-003 program.
Sutacimig is designed as a subcutaneous, first-in-class prophylactic option for GT, a disorder for which no preventive therapy is currently approved. Hemab’s leadership pointed to the long-term extension results as evidence that the drug’s early bleed-reduction effect holds up over time, while the accompanying natural history studies illustrate why that matters: patients with GT and FVIID continue to experience frequent, unpredictable bleeding into adulthood, and only a small share currently receive any form of prophylaxis.
Company leadership described the long-term data as clearing the way, with FDA input, for a Phase 3 program built around a once-weekly dose. An investigator involved in the study added that the extension results – including the first successful use of sutacimig around surgical procedures – support moving the therapy from a reactive treatment model toward routine preventive care.
Phase 2 Long-Term Extension: Key Results
The extension data cover 34 patients with GT, treated for a median of 6.9 months and up to 15.9 months.
- Bleed rate reduction: 92% of participants who had bled during the study’s run-in period saw fewer treated bleeds on sutacimig. Among those who had experienced high-intensity bleeding events – bleeds requiring transfusion, rFVIIa, or hospitalization – in the year before starting treatment, the annualized rate of such events fell by 62% during treatment. Across all dose groups, average annualized treated bleed rates declined, with the low-dose weekly cohort seeing an approximate 84% reduction.
- Surgical outcomes: Three participants underwent procedures – two surgeries and one dental procedure – all with successful control of bleeding; one case required a single additional dose of recombinant Factor VIIa afterward.
- Safety: Adverse events were generally mild to moderate, with no related events at Grade 3 or higher. Three participants had Grade 2 thromboembolic events, occurring in dose groups linked to higher drug exposure and/or additional risk factors; all resolved or were resolving with standard anticoagulation management.
- Regulatory path forward: Based on the Phase 1/2 data package, the FDA has agreed that Hemab can advance directly to Phase 3 using a 0.2 mg/kg, once-weekly dose – a regimen selected to preserve bleed protection while avoiding the higher peak drug levels associated with clotting events earlier in development.
Additional Data Presented
Preclinical FVIID findings: In laboratory models designed to mimic FVIID, sutacimig restored thrombin generation, supporting the company’s rationale for testing the drug as a potential treatment across multiple bleeding disorders.
In variant-binding studies, sutacimig bound 22 of 25 tested Factor VII variants (88%), with binding projected to extend to more than 90% of the variants catalogued in severe-to-moderate FVIID patient databases – pointing to broad applicability for the therapy’s ongoing Phase 2 study in this population.
GT360 natural history study (N=117): More than 90% of pediatric, adolescent, and young adult participants reported bleeding at least weekly, as did 72% of those aged 40 and older. Depressive symptoms were reported three to four times more often than in the general population (32% versus roughly 8–10%), with symptom severity tracking bleed frequency.
ATHN Transcends study (N=49): Over 16.6 patient-years of follow-up, participants who bled experienced an average annualized bleed rate of 25.9, with 44% of bleeding episodes going untreated altogether. Only 14% of patients had received any form of prophylactic treatment.
About Glanzmann Thrombasthenia
Glanzmann thrombasthenia is a rare, severe inherited bleeding disorder that can cause debilitating and occasionally life-threatening bleeding episodes.
Data from the Glanzmann’s 360 natural history study found that the large majority of the 117 participants had bled within the previous week, with most requiring a bleed-related hospital visit within six months, and reported substantial effects on work, school, social life, and travel. No prophylactic treatment is currently approved for GT.
About Factor VII Deficiency
FVIID is a rare inherited disorder involving low levels of Factor VII, a protein essential to blood clotting. Patients with clinically severe disease face recurrent, unpredictable bleeding, including at high-risk sites such as the brain, gastrointestinal tract, and joints, along with frequent nosebleeds and gum bleeding. Female patients face additional risk from heavy menstrual bleeding and potentially life-threatening bleeding after childbirth.
About Sutacimig
Sutacimig (formerly HMB-001) is a subcutaneously administered bispecific antibody engineered to stabilize the body’s own Factor VIIa and direct it to the surface of activated platelets, amplifying clot formation at the site of injury.
It is being developed as a first-in-class prophylactic therapy for GT, with potential application in other bleeding disorders.
The therapy holds Fast Track, Orphan Drug, and Breakthrough Therapy designations from the FDA, Innovative Licensing and Access Pathway designation from the UK’s MHRA, orphan medicinal product status in the EU, and access to the EMA’s PRIME scheme. More information is available at clinicaltrials.gov (NCT06211634).
About Hemab Therapeutics
Hemab Therapeutics Holdings, Inc. is a clinical-stage biotechnology company developing therapies for people affected by serious bleeding and thrombotic disorders.
Its pipeline includes sutacimig for GT and FVIID, HMB-002 (an antibody in development for Von Willebrand disease), and HMB-003 (a preclinical antifibrinolytic candidate for high-unmet-need bleeding conditions). Learn more at hemab.com.
This release contains forward-looking statements regarding Hemab’s clinical development plans, anticipated trial timelines, and the potential of its product candidates. These statements are subject to risks and uncertainties, including those inherent in clinical development, and actual results may differ materially. Hemab undertakes no obligation to update these statements except as required by law. For a full discussion of risk factors, see Hemab’s filings with the U.S. Securities and Exchange Commission.