FACTBOX-UPDATE 1-Blood-thinning drugs may face new competition

(Adds Lovenox, updates introduction with U.S. panel decision on Brilinta)

July 28 (Reuters) - AstraZeneca Plc (AZN.L) drew closer to entering the multibillion-dollar global market for blood-thinning drugs when a U.S. advisory panel voted 7-1 on Wednesday to recommend approval of Brilinta. [ID:nN28178213]

Blood-thinning medicines are used at various stages of cardiovascular disease to prevent clots that can cause heart attacks or strokes.

Here are current approved options and others on the horizon:

PLAVIX

Plavix now holds the title of the world's second-best selling drug with annual revenue topping $9 billion. But sales of the medicine from Sanofi-Aventis SA (SASY.PA) and Bristol-Myers Squibb Co (BMY.N) are expected to drop sharply once generic competition hits the United States in 2012. Cheaper versions already are sold in Europe.

Brilinta, if approved, would compete directly with Plavix for preventing deaths, heart attacks and strokes. Both oral drugs reduce the clumping of blood particles called platelets, that promote clotting.

Low-cost generic versions of Plavix will pose a challenge for Brilinta if it wins approval.

EFFIENT

Plavix already has an anti-platelet competitor from Eli Lilly (LLY.N) and Daiichi Sankyo (4568.T) in Effient. Known generically as prasugrel, the drug won U.S. approval a year ago after studies showed Effient was more effective than Plavix but carried a higher risk of bleeding. Effient carries a strong warning about bleeding risks. Initial sales have disappointed industry analysts, but Lilly remains confident in the drug.

VORAPAXAR

This experimental Merck & Co (MRK.N) drug works in a new way by blocking thrombin, a protein involved in clotting. It likely would be used with antiplatelet drugs such as aspirin and Plavix to prevent heart attacks and strokes. Merck has said it plans to apply for U.S. approval in 2011.

ELINOGREL

This experimental drug from Novartis (NOVN.VX) and Portola Pharmaceuticals is due to enter final-stage trials in 2010. It could offer another alternative to Plavix.

ASPIRIN

A cheap and widely used over-the-counter option for preventing heart attacks. But it may cause potentially fatal stomach bleeding and strokes in a small percentage of patients. Aspirin is an antiplatelet agent.

PRADAXA

Privately held Boehringer Ingelheim is developing Pradaxa as a potential competitor to warfarin, a problematic 50-year-old drug, in patients at risk of stroke due to an irregular heart beat.

Warfarin, the standard therapy for stroke prevention, interacts with food and other medicines and doctors must monitor patients' blood frequently. New anti-clotting pills such as Pradaxa were designed not to have those drawbacks.

Some analysts believe Pradaxa may be the first of a new generation of oral anti-clotting drugs in a market worth more than $10 billion a year. Pradaxa could win approval in late 2010 or early 2011, Boehringer has said.

Pradaxa and warfarin are anticoagulants, drugs that prevent new clots from forming or keep existing clots from enlarging.

XARELTO

Bayer (BAYGn.DE) and Johnson & Johnson (JNJ.N) also are aiming for the stroke-prevention market with Xarelto. In May 2009, the U.S. Food and Drug Administration declined to approve Xarelto for its first use in patients temporarily bedridden after hip and knee replacement surgery, a much smaller market than stroke prevention.

APIXABAN

Pfizer (PFE.N) and Bristol-Myers are developing this oral drug as an alternative to warfarin.

HEPARIN

This injectable anticoagulant, derived from pig intestines, is used in dialysis and heart and other surgeries. Makers include Baxter International (BAX.N).

LOVENOX

A version of heparin sold by Sanofi. U.S. regulators recently approved the first generic version of Lovenox, from Novartis AG (NOVN.VX) and Momenta Inc (MNTA.O). Sanofi is challenging the cheaper copy in court. [ID:nN2699940] (Reporting by Lisa Richwine and Ben Hirschler; Editing by Tim Dobbyn)