Marstacimab (PF-06741086) is a neutralizing antibody that binds to and inhibits inhibitors of the human tissue factor pathway. Marstacimab is an anti-tissue factor pathway inhibitor used in the study of hemophilia.

Marstacimab was able to reduce corn trypsin (CT) levels in whole blood samples from hemophiliacs at concentrations of 20, 50 and 100 nmol/L. [1]
In an in vitro assay, Marstacimab (16 μg/mL) not only shortened the clotting lag time and increased thrombin generation in human non-hemophilic platelet depleted plasma samples, but also increased peak thrombin in hemophilia A and hemophilia B plasma samples. [2]

In a mouse model of acute hemorrhage, Marstacimab administered intravenously at a dose of 0.5 mg/kg had no hemodynamic effects. [2]