Stockholm, Sweden, 30 August: Research conducted in the Netherlands has highlighted the need for care when switching patients under treatment for high cholesterol from branded to generic drug families. The study shows that much of the switching can result in patients inadvertently receiving non-equivalent doses, potentially leading to an increased risk of downstream heart disease and stroke.
Guidelines have been issued by many national healthcare providers to switch patients away from more expensive branded versions of drugs. There should be little risk in such a move, but in a study conducted by Professor Danny Liew of the University of Melbourne that focused on cholesterol-reducing statins, it is clear that prescribed doses are not being sustained. The study was undertaken to determine dose-specific patterns associated with switching patients in the Netherlands from the Lipitor-branded atorvastatin to generic simvastatin. Modelling was then used to predict the increased risk of heart disease and stroke.
The study took a representative sample of pharmacist dispensing data from across the Netherlands, and combined this information with published data on the dose-specific effects of each drug. “Our research demonstrated that many patients were, in fact, receiving a non-equivalent dose after switching to the generic drug,” said Professor Liew. The study found that in the first three months of 2009, over one third of patients who had initially been prescribed Lipitor had been switched to a less potent dose of simvastatin. “The predicted net effect of this would be at least a 5 to 6 percent increase in low-density lipoprotein cholesterol (LDL-C), which translates to a 3 percent average increase in the risk of heart disease and stroke”, concludes Professor Liew.