June 22, 2004
BAY 59-7939 in tests:

New Bayer drug provides effective and predictable anticoagulation

Study findings announced at the 18th International Congress on Thrombosis

- New data from animal and phase I studies of a novel oral, direct Factor Xa inhibitor - BAY 59-7939 demonstrated that it achieved effective anticoagulation without causing liver abnormalities or increases in the risk of bleeding. In these studies BAY 59-7939 was well tolerated over a wide range of dose strengths in more than 170 healthy subjects.

The results were announced at the 18th International Congress on Thrombosis (ICT) held in Ljubljana, Slovenia.

BAY 59-7939 is an oral, direct Factor Xa inhibitor currently undergoing development for the prevention and treatment of thromboembolic disease. The findings of the animal studies and Phase I trials announced at the ICT show that BAY 59-7939 is a highly potent, direct and specific inhibitor of Factor Xa, which represents a critical step in the coagulation cascade. In addition, in animal models, BAY 59-7939 exhibited a high level of bioavailability (more than 80 percent) and was rapidly excreted via the kidneys and the gut.

These studies are part of a major international study program for BAY 59-7939. In addition of these studies phase II-trials are also ongoing. The development goal is to address a current and significant medical need for effective and safe oral anticoagulants that can be given without the need for monitoring.

Therapeutic improvements needed despite advances

Despite the advances made in the treatment of thrombosis and embolism, there is still a great need for new, oral anticoagulants, as a considerable proportion of high-risk patients today still receive insufficient anticoagulant therapy or none at all.

Warfarin is capable of effectively reducing the risk of stroke, but its administration is associated with practical problems. For example, patients have to be tested at frequent intervals to ensure that the drug dosage is still in the right range for safe anticoagulation. Moreover, Warfarin is used too rarely in a large number of high-risk patients, in particular the elderly, due to the fact that it interacts with numerous other drug products and foods, and often requires frequent dosage adaptation.

In hopitalized patients Low Molecular Weight Heparins are currently the cornerstone of anticoagulation therapy. They are generally well tolerated and safe to use. However, since they cannot be administered orally, convenient long-term therapy is a challenge.

Therefore, for optimal care of patients, new, oral, unmonitored anticoagulants are required which would make coagulation testing and dose adjustment unnecessary and could be used safely and conveniently for long-term treatment.

The study findings show that BAY 59-7939, the new Factor Xa inhibitor from Bayer HealthCare, promises to meet the future needs of thrombosis treatment and prevention.

Bayer HealthCare AG, a subgroup of Bayer AG with sales of approximately 8.9 billion Euro in 2003, is one of the world's leading, innovative companies in the health care and medical products industry.

The company combines the global activities of the divisions Animal Health, Biological Products, Consumer Care, Diagnostics Professional Testing Systems and Diagnostics Self Testing Systems and Pharmaceuticals. 34,600 people are employed by Bayer HealthCare worldwide.

Our aim is to discover and manufacture innovative products that will improve human and animal health worldwide. Our products enhance well-being and quality of life by diagnosing, preventing and treating disease.

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