From Google News

• By
• SHIRLEY S. WANG
• CONNECT

AMSTERDAM—Results from a highly anticipated study of Japanese drug maker Daiichi Sankyo Co.'s experimental medication to reduce blood clots showed that it appeared to work as well as the current standard treatment—though no better—and is safer.

The findings suggest that the compound, edoxaban, may become a contender in its class, called factor Xa inhibitors, in the competitive anticoagulant market, which includes Xarelto from Johnson & Johnson and Eliquis from Bristol-Myers Squibb Co. and Pfizer Inc. Edoxaban is approved in Japan but not yet in the U.S.

The 8,000-patient study, presented in a packed auditorium in front of thousands here at the European Society of Cardiology Congress, is the largest clinical trial to date of any factor Xa inhibitor. The data were simultaneously published in the New England Journal of Medicine.

In the study, patients with deep-vein thrombosis, blood clots in legs or other limbs, or pulmonary embolism, clots in the lungs, were either administered edoxaban after first being treated with another anticlotting agent, heparin, or given the standard treatment strategy of a decades-old anticoagulant, warfarin, followed by vitamin K.

After 12 months of follow-up, there was no statistical difference between patients treated with the edoxaban regimen and those with the warfarin treatment in terms of effectiveness of treating the condition, as researchers expected, said Harry Buller, chairman of the vascular medicine department at Amsterdam's Academic Medical Center and the investigator on the study who presented the data. There was some evidence that edoxaban was more effective in the sickest patients compared with warfarin, he said.

Edoxaban also appeared safer than warfarin. There were significantly fewer cases of bleeding, including hemorrhage within the skull, in the edoxaban group compared with those taking warfarin.

Improving on the current treatment for these conditions is difficult because the standard treatment is about 90% effective, said Dr. Buller.

However, there are significant concerns about the side effects, especially bleeding, with older anticlotting agents. Patients on warfarin must be vigilant about the medication's interaction with certain foods or drugs and have regular tests to monitor the amount of drug in their blood.

Patrick O'Gara, director of clinical cardiology at the Brigham and Women's Hospital in Boston and president-elect of the American College of Cardiology, called the study well-conducted and said the results were consistent with the findings from other factor Xa inhibitors in being no better than warfarin in effectiveness.

Compared with warfarin, "we pay less of a price with intracranial hemorrhage [with edoxaban]," said Dr. O'Gara, who wasn't involved with the current study. However, more research is needed to differentiate between the newer anticoagulants because there have been no head-to-head studies of these drugs to date, said Dr. O'Gara.

Write to Shirley S. Wang at shirley.wang@wsj.com