Engineered Protein Controls Bleeding in Severe VWD

Results of a Phase III study show that BAX 111, a highly purified recombinant von Willebrand factor (rVWF) analog manufactured by Baxalta, appeared safe and effective for treatment of bleeding episodes in patients with severe von Willebrand’s disease (VWD).

In the study, 37 patients were assigned to one of four arms composed of rVWF (50 IU/kg or 80 IU/kg) with or without rVIII (Advate, Baxalta). Most patients also received as-needed treatment with rVWF of 40 IU/kg to 60 IU/kg for regular bleeding episodes and up to 80 IU/kg for major bleeds. Overall, 22 patients experienced 192 bleeding episodes (122 minor bleeds, 61 moderate bleeds and 7 major bleeds). A single infusion proved effective for 81.8 percent of bleeding episodes. Using a four-point scale, the researchers rated 96.9 percent of bleed control as excellent. One-hundred percent of patients achieved treatment success, defined as a mean efficacy rating of less than 2.5. Eight adverse events occurred, including two serious adverse events (chest discomfort and increased heart rate without cardiac symptomatology) that occurred concurrently in one patient. However, no thrombotic events or severe allergic reactions occurred. And, the researchers did not detect the development of any VWF or FVIII inhibitors, anti-VWF-binding antibodies or antibodies against host-cell proteins.