Hemab reported positive Phase 1 HMB-002 data showing dose-dependent increases in VWF and FVIII with monthly dosing potential in Von Willebrand disease and introduced HMB-003 for heavy menstrual bleeding.
Written By: Nalam Karthik, PharmD
Reviewed By: Pharmacally Editorial Team
Hemab Therapeutics has presented new first-in-human clinical data for HMB-002, an investigational antibody for Von Willebrand disease (VWD), alongside the introduction of HMB-003, a peptide-based plasmin inhibitor being developed for heavy menstrual bleeding. The data were presented at the International Society on Thrombosis and Haemostasis (ISTH) 2026 Congress in Paris.
The HMB-002 findings demonstrated proof of mechanism, with dose-dependent increases in endogenous Von Willebrand Factor (VWF) and Factor VIII (FVIII), restoration of key coagulation biomarkers, and a pharmacokinetic profile that supports potential monthly subcutaneous dosing. The company also unveiled HMB-003 as a non-hormonal antifibrinolytic candidate with extended activity that could provide cycle-matched treatment for heavy menstrual bleeding.
HMB-002 Targets the Underlying Biology of Von Willebrand Disease
Von Willebrand disease is the most common inherited bleeding disorder and results from quantitative or qualitative defects in VWF, a protein essential for normal blood clotting. Patients frequently experience recurrent mucosal bleeding, easy bruising, and heavy menstrual bleeding, while severe cases may develop life-threatening hemorrhage. Current therapies largely replace missing clotting factors or temporarily increase circulating VWF but do not directly address the underlying mechanism responsible for VWF degradation.
HMB-002 takes a different approach by targeting the C-terminal CK domain of VWF, protecting the endogenous protein from degradation and increasing circulating VWF and FVIII without replacing clotting factors.
Phase 1 Data Show Dose-Dependent Increases in VWF and FVIII
The first-in-human study evaluated single ascending subcutaneous doses of HMB-002 in adults with Type 1 VWD. Across all dose cohorts, treatment produced dose-dependent increases in VWF and FVIII. In the highest evaluated 150 mg cohort, both biomarkers increased by at least 2.4-fold, accompanied by normalization of thrombin generation, shortening of activated partial thromboplastin time (APTT), and maintenance of normal VWF multimer distribution. Pharmacokinetic and pharmacodynamic findings indicated sustained exposure consistent with potential monthly dosing.
Although the single ascending dose study was not designed to assess efficacy, preliminary clinical observations were encouraging. Eight of nine evaluable participants experienced no treated bleeding episodes during the 28 days after receiving HMB-002. Before treatment, participants had a mean annualized treated bleeding rate (ATBR) of 20.1, reflecting substantial disease burden, while the observed post-treatment mean ATBR was 1.6 during the evaluation period.
Safety Profile Supports Continued Clinical Development
Safety findings were favorable across all dose cohorts. Most treatment-emergent adverse events were mild to moderate, with no serious adverse events or treatment discontinuations attributed to HMB-002. Investigators also reported no thromboembolic events, thrombocytopenia, injection-site reactions, or hypersensitivity reactions.
Company and Clinical Experts Highlight Potential Paradigm Shift
Commenting on the findings, Hemab Chief Executive Officer Benny Sørensen, MD, PhD, said the data support a non-replacement strategy that raises endogenous VWF and FVIII while providing early clinical evidence of reduced bleeding episodes. He also highlighted HMB-003 as a non-hormonal treatment candidate for heavy menstrual bleeding, an area with limited therapeutic innovation despite its substantial impact on women’s health.
Priyanka Raheja, MD, Consultant Haematologist at Barts Health NHS Trust, said the results support the potential of HMB-002 to modify the treatment approach in VWD by increasing endogenous clotting factors rather than replacing them, while maintaining a favorable safety profile.
Hemab Expands Pipeline with HMB-003
Hemab also introduced HMB-003, a subcutaneous fatty-acid-conjugated peptide that directly inhibits plasmin to prevent fibrinolysis. In preclinical studies, the candidate selectively inhibited plasmin without affecting thrombin generation, platelet function, or coagulation pathways. A single dose in minipigs produced sustained antifibrinolytic activity for approximately one week, supporting development as a cycle-matched therapy for heavy menstrual bleeding and potentially other bleeding disorders.
Path Forward
HMB-002 is currently being evaluated in the Phase 1 study (NCT06610201), with further clinical development planned under the Phase 2 program (NCT06754852). The company intends to continue advancing both HMB-002 and HMB-003 as part of its portfolio targeting inherited and acquired bleeding disorders.
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About the Writer
Nalam Karthik (LinkedIn) is a healthcare writer and PharmD graduate with interests in pharmacovigilance, drug safety, clinical data analysis, and quality assurance. He is passionate about translating clinical and pharmaceutical knowledge into accessible healthcare content while staying engaged with advancements in drug development and patient safety initiatives.