(New throughout, adds filing details, background, share price)
Aug 28 (Reuters) - Amgen Inc said on Thursday it applied to U.S. health regulators to sell its cholesterol fighter, evolocumab, becoming the first company to seek approval of a medicine from a closely watched new class of potent heart drugs.
Amgen is racing with Regeneron Inc to bring to market the potentially lucrative new drugs aimed at patients unable to tolerate widely used statins, and those who cannot sufficiently lower cholesterol despite use of statins, such as Pfizer Inc's Lipitor, or other medicines.
The injectable drugs work by blocking a naturally occurring protein called PCSK9 that prevents the liver from removing LDL cholesterol, the "bad" cholesterol, from the bloodstream.
In large clinical trials, evolocumab cut LDL levels by more than 50 percent even in patients already taking other cholesterol medicines.
Analysts have forecast multibillion-dollar sales for the new biotech drugs, if they demonstrate an ability to significantly reduce heart attacks and deaths in larger ongoing trials, as statins have.
While Amgen was the first to file for U.S. approval of a PCSK9 inhibitor, Regeneron and French partner Sanofi have an ace up their sleeve that could enable them to catch up or even reach the market first with their drug, alirocumab.
In late July, the companies said they paid $67.5 million to acquire a special voucher from BioMarin Pharmaceutical Inc that could assure alirocumab an expedited six-month U.S. regulatory review, rather than the standard 10 months.
Pfizer Inc is also developing a PCSK9 inhibitor, but is behind Amgen and Regeneron.
Amgen is expected submit approval applications for evolocumab to regulators in Europe and other markets in the coming months.
Amgen shares were up 77 cents, or 0.6 percent, at $138.60, while Regeneron shares were off 76 cents, or 0.2 percent, at $349.25 on Nasdaq. (Reporting by Bill Berkrot; additional reporting by Natalie Grover in Bangalore; Editing by Maju Samuel and David Gregorio)