This Wall Street Journal ($) article reports on the reaction of pharmaceuticals giant Merck & Co. to the disappointing study involving Zocor, its top-selling cholesterol drug.
The study found that high doses of the drug did not benefit patients at high risk of a heart attack compared with both placebo and less-aggressive Zocor treatment. Researchers presented the 4,500-patient Zocor study at the annual meeting of the European Society of Cardiology in Munich, Germany, and it also was published online by the Journal of the American Medical Association.
Even before this news, Merck had been losing in the competition with Pfizer‘s Lipitor, which is the world’s biggest-selling statin drug with sales of $9.2 billion in 2003. A clinical trial reported earlier this year that Lipitor was was much better than another statin — Bristol-Myers Squibb Co.’s Pravachol — at reducing the risk of death, heart attack or other serious complications within two years of treatment. Here is an earlier post on that study.
The 4,500-patient study tested an aggressive cholesterol-lowering strategy compared with a moderate approach for patients hospitalized with severe unstable chest pain. The aggressive treatment was 40 milligrams of Zocor for a month followed by 80 milligrams for the next 23 months. The moderate approach was four months of a placebo followed by 20 milligrams of Zocor.
In the earlier Lipitor/Pravachol study, Lipitor at a dose of 80 milligrams proved significantly more effective in reducing LDL and the risk of serious heart problems than Pravachol at 40 milligrams. The benefit for Lipitor was evident within 30 days of starting the drug and the study was an important reason why cardiology experts are now recommending that doctors consider aggressive therapy with statins to enable patients at very high risk of a heart attack to reduce their levels of LDL to below 70. Previously, the target for such patients was below 100.
Cardiologists expected aggressive treatment with Zocor to reflect the Lipitor findings, especially because the control group was treated with a placebo during the first four months of the two-year trial. But even though their LDL levels fell to 62, aggressively treated patients at the end of four months had no difference in heart attacks, death from heart attacks, or strokes for heart problems than patients on placebo whose LDL was twice as high. After two years, 14.4% patients on aggressive therapy had suffered negative outcomes compared with 16.7% on the moderate regimen, but the difference was not considered statistically significant.