UPDATE 1-J&J/Bayer blood clot drug beats Lovenox in trials

(Adds data from trials, researcher quotes)

NEW YORK, Dec 10 (Reuters) - Johnson & Johnson (JNJ.N) said on Monday that a pill it is developing with Bayer AG BAYG.DE was far better able to prevent blood clots among patients after knee and hip replacements than the current standard of care, suggesting blockbuster sales potential.

Positive results from the two late-stage trials were as dramatic as those from another Phase 3 study that was presented on Saturday and also pitted the experimental medicine, rivaroxaban, against Sanofi-Aventis' (SASY.PA) widely used injectable Lovenox.

Moreover, patients taking the experimental medicine had no statistically greater incidence of bleeding than those taking Lovenox and no significant risk of liver injury, clearing two common roadblocks for approval of anti-clotting medicines.

"These are absolutely dramatic results, which could lead to a revolution in anti-coagulation therapy," said Dr. Alexander Turpie, a professor of medicine from McMaster University who has helped oversee the trials.

"Here we have an oral drug that does not require monitoring and which provided a significant reduction in total, major and symptomatic blood clots," compared with Lovenox, Turpie said in a telephone interview.

The latest results for rivaroxaban, which Bayer has said has potential to garner sales approaching $3 billion a year, came from a pair of late-stage trials described on Monday at the annual meeting of the American Society of Hematology in Atlanta.

Another Phase 3 trial presented Saturday at the meeting, dubbed Record 1, provided similarly impressive data on effectiveness and safety among patients taking the once-daily pill to prevent blood clots after hip-replacement surgery.

Rivaroxaban easily met its primary goal in that study by proving 70 percent better able to cut risk of all types of venous thromboembolism, meaning blood clots, than Lovenox. And it easily met its secondary goal by being 88 percent better able to cut risk of major clots, defined as clots that caused death or which lodged in the upper part of the legs or in the lungs.

In another trial involving hip-replacement patients, called Record 2, researchers on Monday said patients receiving rivaroxaban had 79 percent fewer total clots and 88 percent fewer major clots, compared with those getting Lovenox.

Patients in both treatment groups had a similar rate of major bleeding, although rivaroxaban was taken for an extended period of about 35 days, compared with only up to 14 days for Lovenox.

Knee-replacement patients in the other trial described on Monday, called Record 3, had 49 percent fewer total clots and 62 percent fewer major clots, compared with Lovenox. Rates of major bleeding were similar among patients taking rivaroxaban and Lovenox, which were both given for 10 to 14 days after surgery.

Germany's Bayer has already asked European regulators to approve rivaroxaban to prevent clots after major orthopedic surgery.

Bayer and J&J are conducting earlier-stage trials to determine whether rivaroxaban can prevent strokes among patients with atrial fibrillation, a type of irregular heartbeat that particularly affects the elderly.

That use of the drug is by far its biggest commercial opportunity, analysts say, because the only oral clot preventer now available for such patients is warfarin -- which can cause serious bleeding and requires patients to strictly control their diets and undergo frequent blood tests to ensure their blood is clotting neither too easily nor too slowly.

One of the world's most prescribed medicines, warfarin is sold under the brand name Coumadin by Bristol-Myers Squibb Co (BMY.N) and also by various generic drug companies.

(Reporting by Ransdell Pierson; Editing by Lisa Von Ahn)

((Reuters Messaging: ransdell.pierson.reuters.com@reuters.net; 646-223-6034; ransdell.pierson@reuters.com)) Keywords: J&J BAYER/CLOTS

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