By Bill Berkrot
WASHINGTON, March 18 (Reuters) - Longer-term use of the oral blood thinner Xarelto significantly cut the risk of recurrence of potentially life-threatening blood clots with no additional major bleeding compared with low-dose aspirin in patients at elevated risk, according to data presented on Saturday.
Researchers said the results could change treatment of patients who have suffered dangerous blood clots known as venous thromboembolisms (VTE). It could also give a modest boost to sales of Xarelto, sold by Johnson & Johnson and Bayer AG , if the longer-use strategy is widely adopted.
VTE, which includes painful deep vein thrombosis and often deadly pulmonary embolism, affects more than 900,000 Americans each year.
Due to a high risk of recurrence, guidelines currently call for anticoagulant therapy with a drug like Xarelto for three months or longer. Once anticoagulant therapy is stopped, many patients are given aspirin for long-term prevention.
The study, dubbed Einstein Choice, involved 3,396 patients who had completed 6 to 12 months of anticoagulant therapy for a VTE. They were then given either 10 or 20 milligrams of Xarelto, known chemically as rivaroxaban, or low-dose aspirin and followed for another year.
Just 1.2 percent of patients who got 10 mg Xarelto and 1.5 percent in the 20 mg group suffered another VTE, compared with 4.4 percent on aspirin. The result was statistically significant.
The incidence of major bleeding, the greatest health risk from drugs like Xarelto, was very low and no different from aspirin, ranging from 0.3 percent to 0.5 percent.
"The demonstrated safety of both 20 and 10 mg of rivaroxaban to prevent recurrent VTE in the extended treatment setting will add flexibility and comfort for doctors, and it should result in better patient outcomes," said Dr. Philip Wells, who presented the data at the American College of Cardiology scientific meeting in Washington.
Wells, chief of the Department of Medicine at the University of Ottawa, said Xarelto appears to be highly protective against recurrent VTE.
Xarelto belongs to a newer class of oral blood thinners along with Eliquis from Pfizer and Bristol-Myers Squibb and Pradaxa from Boehringer Ingelheim.
The study generally involved subjects younger than typical VTE patients, Wells said. More trials are needed to determine if Xarelto is equally effective in other patient populations, he said.
This study, however, "demonstrates no role for aspirin in VTE, which should change practice," said Wells.
(Editing by Hugh Lawson)