Results of a recent study published in the journal Haemophilia, highlights the potential of a novel approach to hemophilia therapy that targets an anticoagulant protein known as tissue factor pathway inhibitor (TFPI).
Developed by Pfizer, marstacimab is a laboratory-engineered monoclonal antibody designed to treat hemophilia A and B patients, with or without inhibitors. It works by blocking and effectively preventing TFPI from performing the anticoagulant function that it naturally carries out in the human body. This unique therapy, which is being investigated for both subcutaneous and intravenous administration, would allow treaters to forgo the need for traditional factor VIII (FVIII) or factor IX (FIX) replacement in individuals with hemophilia A or B.
Investigators collected blood and plasma samples from 12 participants with either hemophilia A or B, regardless of the presence of inhibitor antibodies. Through a series laboratory assays, these samples were exposed to a placebo solution, missing factor FVIII or FIX or marstacimab. The data showed that the introduction of marstacimab shortened the clotting time in all patient blood and plasma samples. Results showed that the therapy also boosted production of thrombin, a key plasma-based enzyme that contributes to the coagulation process. Investigators also noted that the procoagulant effects of the treatment were comparable to recombinant FVIII or IX.
Marstacimab, which has already received Orphan Drug Designation from the U.S. Food and Drug Administration, has been investigated in multiple clinical trials, with more planned for the future.
A “first‐in‐human” phase 1 trial demonstrated the safety, tolerability, and favorable distribution in the body of the therapy in healthy volunteers. A recently completed phase 1/2 trial evaluated the safety and efficacy of the therapy via multiple subcutaneous and/or intravenous doses administered to adults with severe hemophilia. Pfizer also has planned a phase 3 clinical trial focused on teenagers and adults from 12 to 74 years of age, with severe hemophilia A or B.
Source: Hemophilia News Today, August 19, 2019