Abbott Laboratories Inc's experimental drug TriLipix was able to improve cholesterol and triglyceride levels significantly in patients for a year after earlier three-month trials.

TriLipix – a derivative of Abbott's $1.2 billion-a-year TriCor treatment for triglycerides – is awaiting U.S. marketing approval, were presented at the annual scientific meeting of the American Heart Association in New Orleans.

Abbott expects approval of TriLipix this year, well before TriCor, another member of the fibrate class of drugs, begins facing possible generic competition in 2011. By switching patients over to TriLipix ahead of time, Abbott could inherit current TriCor patients and keep new ones from opting for cheaper TriCor copycats once they hit the marketplace.

Some 2,700 patients with cholesterol problems initially participated in 12-week studies, during which they took TriLipix in combination with one of three widely used statin cholesterol fighters – AstraZeneca's , Crestor, Merck & Co's , Zocor or Pfizer Inc's , Lipitor – or took TriLipix or a statin by themselves.

"Fundamentally, this drug has a data set to show safe use with statins for the very large population" with cholesterol problems, said Dr. Harold Bays, a lead researcher on the Abbott-sponsored study. He noted the year-long follow-up was the largest study ever conducted for combination use of statins and a fibrate.

About 1,900 patients who elected to participate in the ensuing 52-week extension study received TriLipix plus the moderate dose of the statin they had taken in the initial studies.

By the end of that period, the combination therapy cut levels of triglycerides — a type of blood fat that is harmful to the cardiovascular system — by 47.5 percent, researchers said. That represented a sustained response from the 45.7 percent decline seen in the 12-week studies.

Levels of "bad" LDL cholesterol fell almost 38 percent, compared with a 32.2 percent drop in the shorter studies. Heart-protective HDL cholesterol rose almost 24 percent, an improvement from the 17.6 percent boost seen in the initial 12 weeks.

Statins excel at reducing LDL cholesterol and can raise HDL levels by as much as 10 percent. But they have no major effect on triglycerides, a reason that TriCor is widely prescribed.

Although Tricor is not approved for use with statins, many doctors prescribe it that way because they are free to prescribe medicines in any way they wish. Abbott has asked the U.S. Food and Drug Administration for permission to market TriLipix either by itself or with statins. Approval would allow Abbott to advertise widely and market the new fibrate as a companion to statins, an advantage not allowed for TriCor. Statins are already the world's most widely used prescription medicines. The FDA last month said it needs more time to review the TriLipix marketing application.