Germany´s giant pharmaceutical Bayer AG announced their anticoagulant pill Xarelto (generically rivaroxaban) has been approved by the European Commission.

Xarelto had been recommended by the European Medicines Agency in July, and already approved by Canadian health regulators mid-September. Bayer and U.S. partner Johnson & Johnson (J&J) are awaiting approval by U.S. health authorities, as the drug was filed with the Food and Drug Administration (FDA) at the end of July. If approved, J&J unit Ortho-McNeil will be marketers and distributors in the U.S.

The approval of Xarelto, in the words of CEO Werner Wenning, “is an important milestone for Bayer.” Potential annual sales of this rival to Sanofi-Aventis´ top-seller Lovenox, are some $ 3 billion dollars (2 billion euros).

The blood-thinning pill works at a key stage in the clotting process, directly inhibiting the Factor Xa enzyme to stop coagulation – drugs known as Factor Xa inhibitors – and it is taken once-daily. It has been approved for the prevention of venous blood clots in adult patients undergoing hip or knee replacement surgery.

However, Bayer and U.S. development partner J&J have further, more profitable marketing goals for this drug. Xarelto is to be tested in a 50,000 patient Phase III clinical trials to evaluate the product in the prevention and treatment of a broad range of acute and chronic blood-clotting disorders including VTE treatment, stroke prevention in patients with atrial fibrillation, and secondary prevention of acute coronary syndrome. Results of a phase II trial for preventing ACS in vulnerable patients will most likely be presented in November at the American Heart Association's annual meeting in New Orleans, the companies had previously announced.

The EU marketing approval for Xarelto was based on review of data from the extensive RECORD clinical program that included three Phase III trials of Xarelto involving nearly 10,000 patients undergoing elective hip or knee replacement surgery (RECORD1, 2 and 3 trials).

Results from these three studies demonstrated the superior efficacy of Xarelto, both in head-to-head comparisons with Lovenox (enoxaparin) (RECORD1 and 3) as well as when comparing extended-duration (5 weeks) Xarelto with short-duration (2 weeks) Lovenox (RECORD2). In all three trials, Xarelto and Lovenox had comparable safety profiles including low rates of major bleeding.

Xarelto will be competing with current standard treatment Lovenox, Sanofi-Aventi´s top seller with sales of over $ 2.13 billion dollars in the first half of this year. On the market, approved since March, is Boehringer-Ingelheim´s Pradaxa, an oral direct thrombin inhibitor. In Phase II clinical trials is apixaban (also in the class of Factor Xa inhibitors), being jointly developed by Bristol-Myers Squibb and Pfizer Inc.