HMB-001 is designed to bind and stabilise endogenous Factor VIIa using one antibody arm, while the second arm targets TLT-1 on activated platelets

Hemab Therapeutics

Hemab Therapeutics announces positive Phase 1 data for HMB-001. (Credit: ANIRUDH on Unsplash)

Hemab Therapeutics said that its bispecific antibody HMB-001 was well tolerated in the ongoing Phase 1/2 trial of patients with bleeding disorder Glanzmann Thrombasthenia.

HMB-001 is engineered to bind and stabilise endogenous Factor VIIa using one antibody arm, while the second arm targets TLT-1 on activated platelets.

The bispecific antibody is currently being developed as a prophylactic treatment for Glanzmann Thrombasthenia. It already has fast track designation from the US Food and Drug Administration (FDA) for this indication.

The Phase 1/2 first-in-human open-label trial is assessing the safety, tolerability, pharmacokinetics, and pharmacodynamics of HMB-001. The first patient in the Phase 2 multiple ascending dose part was dosed in December last year.

Under the Phase 1 single-ascending dosage conducted in the UK, seven patients received subcutaneous HMB-001 at 0.2mg/kg, 0.5mg/kg, or 1.25mg/kg.

HMB-001 was well tolerated for the course of a 56-day monitoring period with mild or moderate common adverse events (AEs).

There were no major adverse events or AEs linked to HMB-001 with no thromboembolic events or dose-limiting effects.

Additionally, HMB-001 therapy caused a dose-dependent pharmacodynamic effect of endogenous Factor VIIa accumulation. This was linked to reductions in prothrombin time and enhancements in exploratory thrombin generation analyses.

HMB-001’s pharmacokinetic characteristics and half-life support either a less frequent or every two weeks dosage schedule, the clinical-stage biotechnology company said.

Hemab Therapeutics HMB-001 senior director and programme lead Joe Vogel said: “The first clinical data for HMB-001 in Glanzmann suggest that the demonstrated mechanism is suitable as a new prophylactic treatment for people with neglected blood clotting disorders who face severe, potentially life-threatening bleeds every day.

“With Phase 2 already underway, we are committed to advancing clinical evaluation of HMB-001 toward bringing life-changing preventative treatments to improve patients’ quality of life.”

Hemab Therapeutics is said to be actively recruiting participants in the Phase 2 part of the study, which will be expanded to include sites in the US and Europe.