Generic atorvastatin is as effective as the brand-name drug (LIPITOR(®)) in lowering cholesterol levels: a cross-sectional retrospective cohort study

BACKGROUND: In a world of ever increasing health care costs, generic drugs represent a major opportunity to ensure access to essential medicines for people who otherwise would be unable to afford them. However, some clinicians and patients are still questioning the safety and effectiveness of generic formulations compared to the proprietary drugs necessitating further systematic research analyzing the generic drugs’ efficacy. Our objective was to compare the lipid lowering effects of generic and branded atorvastatin. METHODS: This cross-sectional, retrospective cohort study was conducted at the University of Malaya Medical Centre from 1 May 2013 until 30 May 2013. We analyzed the lipid profiles (total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides) of 629 patients before and at least 3 months after switching them from proprietary atorvastatin (Lipitor(®)) to generic atorvastatin (atorvastatin calcium from Ranbaxy Laboratories, Inc.). We also investigated if there was any difference in the effectiveness of both atorvastatin formulations in various ethnic groups. RESULTS: 266 patients were included in this study. When comparing the median values we found no statistically significant differences (Wilcoxon signed-rank test; p < 0.05) between proprietary and generic atorvastatin in lowering total cholesterol (4.60 mmol/l pre-transition vs. 4.50 mmol/l post-transition; p = 0.583), LDL-cholesterol (2.42 mmol/l vs. 2.41 mmol/l; p = 0.923) and triglycerides (1.50 mmol/l vs. 1.50 mmol/l; p = 0.513). While there was a statistically significant (p = 0.009) difference in HDL-cholesterol levels favouring proprietary atorvastatin, the extent of this change (1.26 mmol/l vs. 1.25 mmol/l) was deemed not to be clinically relevant. There was no statistically significant difference when analyzing the effects on various ethnic groups. CONCLUSIONS: Substituting proprietary atorvastatin for its generic formulation atorvastatin calcium does not result in a less effective management of hyperlipidemia. Our findings lend support to the approach of lowering health care costs by switching patients from branded drugs to their less expensive generic analogues.