New preclinical data from Baxter's BAX 499 hemophilia study presented at ISTH

Baxter International Inc. (NYSE: BAX) announced today that new data from a series of studies on BAX 499, an investigational compound for potential subcutaneous hemophilia therapy, were presented this week during the 23rd annual congress of the International Society on Thrombosis and Haemostasis (ISTH) in Kyoto, Japan. BAX 499 is in early stage clinical development to treat blood clotting disorders hemophilia A and B by targeting a novel pathway responsible for regulating the clotting process. The studies presented at ISTH validate the pathway as a potentially viable target for the treatment of hemophilia.

BAX 499 is being studied in a Phase I clinical trial for potential subcutaneous administration that specifically targets to reduce activity of the tissue factor pathway inhibitor (TFPI), which plays a critical role in the blood coagulation cascade. By blocking this inhibitor activity, the treatment may help achieve blood clotting in people with hemophilia.

Targeting TFPI with BAX 499

One oral presentation, "Tissue factor pathway inhibitor aptamer as a potential drug for hemophilia treatment" evaluated whether BAX 499 might block the inhibitory activity of TFPI in an in vitro model by measuring the impact of BAX 499 on the generation of thrombin, a key protein necessary for forming a blood clot. In this in vitro model, increasing concentrations of BAX 499 improved the rate and amount of thrombin generated, and at the highest levels, thrombin generation was similar to normal coagulation patterns.

"We are encouraged by these data that help deepen our understanding of potential new approaches to address complex blood disorders," said Hartmut Ehrlich, M.D., vice president, global research and development and medical affairs, Baxter's BioScience business. "The studies presented on BAX 499 validate tissue factor pathway inhibitor as a viable target for subcutaneous hemophilia therapy and we look forward to sharing future data as they become available."

Related studies presented during ISTH evaluated the interference of BAX 499 inhibition on TFPI, and considered the biological activity of TFPI and the unique mechanisms of the compound that help block TFPI activity. In addition to BAX 499, data were presented on Baxter's preclinical research studying an approach to inhibit TFPI by small peptides.