By Ben Hirschler

LONDON, May 19 (Reuters) - Amgen's new cholesterol drug Repatha could be recommended for approval in Europe as early as this week, putting it ahead in a race with a rival product from Sanofi.

Repatha, or evolocumab, belongs to a new class of cholesterol-lowering drugs known as PCSK9 inhibitors that clinical trials suggest may slash the risks of heart attacks compared to standard treatment alone.

According to an agenda posted on the European Medicines Agency's (EMA) website on Tuesday, a committee of experts will consider whether to recommend the medicine at a four-day meeting concluding on May 21. (http://www.ema.europa.eu/docs/en_GB/document_library/Agenda/2015/05/WC500186948.pdf)

The fact Repatha is being discussed this week does not automatically mean a decision will be taken, since experts may decide they have further questions.

The EMA is likely to communicate its decision on this and other new drugs around 1100 GMT on May 22. Recommendations for marketing approval by its Committee for Medicinal Products for Human Use (CHMP) are normally endorsed by the European Commission within a couple of months.

Amgen's Repatha is in a race to market with Praluent, which is being developed by Sanofi and its partner Regeneron Pharmaceuticals.

Numerous trials have shown that PCSK9 inhibitors significantly lower blood levels of "bad" LDL cholesterol, but widespread use will hinge on whether the drugs are proven to prevent death, heart attacks and other serious heart problems.

The experimental drugs are antibodies designed to target the PCSK9 protein that maintains LDL cholesterol in the bloodstream. They work differently from statins, which block the liver's production of LDL cholesterol in the first place.

Both Amgen and Sanofi have filed for approval of their drugs based on trials showing that they lower LDL in patients whose cholesterol is not controlled by other drugs, those who cannot tolerate other drugs and people genetically predisposed to high cholesterol.

The U.S. Food and Drug Administration is slated to decide on Amgen's application for Repatha by Aug. 27, while the deadline for Praluent, also known as alirocumab, is July 24.

Neither Amgen nor Sanofi expect definitive data on cardiovascular outcomes for their drugs until larger trials conclude in 2017.

Pfizer, which has not yet filed for approval of its PCSK9 drug, expects outcomes data in a similar time frame.

(Editing by David Clarke)