TRENTON, N.J. (AP) — Researchers will continue a study of a controversial Merck & Co. cholesterol drug after safety monitors decided data so far indicate the drug is safe and effective, the company said Thursday.
The drugmaker said the data safety monitoring board overseeing the study, called IMPROVE-IT, did a preplanned analysis of results halfway through the study.
"The trial will wrap up in approximately June of 2013," said Merck spokesman Lee Davies.
The study is meant to include about 18,000 patients worldwide. So far nearly 17,000 patients have been enrolled.
The study is intended to determine whether Merck's combination cholesterol pill Vytorin prevents heart attacks, strokes and deaths more than just one of its components, Zocor, which is available as a cheap generic pill. Pricey Vytorin also includes, Zetia, a brand-name cholesterol drug that works in a different way.
Merck ran into trouble when it delayed release of another study showing Vytorin didn't prevent plaque buildup in neck arteries any better than Zocor.
After a congressional panel started investigating the delay, Merck released partial results of that study, called ENHANCE, in January 2008. Critics contended that Merck deliberately held up release of the results to protect sales of Zetia and Vytorin.
At the time, the two drugs brought in about $5 billion a year for Merck and its then-joint venture partner Schering-Plough Corp. Merck bought Schering-Plough in November for $41 billion.
Sales of both drugs dropped sharply after the ENHANCE results were released, but they have since recovered somewhat. Together they had sales of about $4.3 billion last year.