Summary
There is a question of bias in this study. It is not prospective, not randomized and not blinded and thus no valid conclusions can be made. The study should be ignored. It will have no impact on sales.
Analysis
This study was a retrospective analysis of medical and pharmacy claims and records to compare cardiovascular (CV) event rates and risk in patients without previous CV disease in whom atorvastatin or simvastatin was newly initiated in a managed care setting. The study concluded that risk of CV events was lower among patients taking atorvastatin compared with patients taking simvastatin. The study was funded by Pfizer, the manufacturer of Lipitor (atorvastatin). All four authors had economic ties to Pfizer. One author was a Pfizer employee and one was a paid consultant. There is no information presented as to why the drugs were prescribed nor is there information regarding the specific choice or dose of the drugs. For all we know, simvastatin could have been prescribed in a majority of smokers (who have a higher cardiovascular risk). More importantly and for a similarly unknown reason, the average dose of atorvastatin utilized was a relatively more potent dose than the average dose of simvastatin. This study is certainly not a fair comparison and the possibility of bias cannot be ignored.
