Factor VIII Deficient Plasma with Inhibitor is drawn from a human donor demonstrating a specific inhibitor to factor VIII. Plasmas are available with a variety of Bethesda Unit titers. Recommended storage for this fresh frozen plasma is -70° C. Factor VIII Deficient Plasma with Inhibitor is tested and found non-reactive for HIV and HBsAg. When doing factor assays, it is critical to have only a single factor deficient in the substrate plasma (monospecificity).