The results come from a survey of previous studies worldwide, rather than new clinical tests on patients. It was released Saturday by Institut fuer Qualitaet und Wirtschaftslichkeit im Gesundheitswesen.
The study follows a controversy in Germany about the pricing of Lipitor, made by Pfizer Inc. and other statin drugs, which aim to reduce cholesterol levels, reports The Associated Press.
According to IQWiG, life-prolonging results for patients suffering from chronic coronary heart disease was seen with Merck & Co.'s Zocor and Bristol-Myers Squibb Co.'s Pravastin - but not with Lipitor.
Jonathan Jones at Pfizer U.K.'s Cardio-Vascular Group says he can't comment directly without studying IQWiG's analysis.
However he notes that the side effects of the rival medicines differed, and that any study could yield different answers depending on the weight given to them.
Representatives based at Pfizer's New York headquarters did not return calls to the AP on Sunday.
In acute diseases, there weren't enough data to prove that any of the group - Lipitor, Zocor or Pravastin - was better than the other.
With diabetes mellitus, only Merck's Zocor was shown to prolong life.
