Bayer’s busy week has continued with the news that the German drugmaker has filed an application with European regulators to sell its first-in-class oral blood thinner Xarelto.

The Leverkusen-headquartered firm announced the submission of a marketing authorisation application to the European Agency for the Evaluation of Medicinal Products to market Xarelto (rivaroxaban) for the prevention of venous thromboembolism after major orthopaedic surgery of the lower limbs. The filing is principally based on data from three Phase III studies of rivaroxaban involving nearly 10,000 patients which reveal that the drug, which has been co-developed with Johnson & Johnson, significantly reduces the risk of VTE in patients undergoing total knee replacement surgery compared with Sanofi-Aventis’ Lovenox (enoxaparin), the current standard of care therapy.

Importantly the postive data on Xarelto, a Factor Xa inhibitor, was achieved with no increased risk of major bleeding compared to Lovenox or any signal of abnormal liver function tests.

Bayer noted that in the European Union there are 543,000 deaths due to VTE each year and people undergoing major surgery, in particular total knee or hip replacement, are prone to developing it due to prolonged bed rest, damage to blood vessels and an increased tendency of the blood to clot. It is estimated that up to 50% of patients undergoing lower limb surgery develop VTE if they do not receive preventative care.

Kemal Malik, head of global development at Bayer, said that “as an effective and convenient, once-daily oral treatment with a reassuring safety profile, we feel confident that rivaroxaban has the potential to set a new standard of care."

Given how big an earner Lovenox is for Sanofi (633 million euros in the third quarter), the potential for Xarelto becomes clear. Earlier this week, analysts at JP Morgan said that there is a 60% probability of Xarelto achieving peak sales of 5 billion euros.