Aims: This short report was designed to provide 2-year follow-up data from a previous study carried out in a primary care practice in the UK to assess the clinical and practical implications of switching to generic drugs.
Methods: All patients previously switched from atorvastatin to simvastatin or losartan to candesartan were reviewed retrospectively 2 years after the switch. Total serum cholesterol and clinic blood pressure readings were used along with records of cardiovascular events occuring during the 2 year period to assess the clinical impact of the switch.
Results: Of the 69 patients switched from atorvastatin to simvastatin between March and September 2005, 65 are still registered at the practice. Of these, 61 (94%) are still on simvastatin and 58 (89%) on the same dose. There was no significant change in mean total cholesterol over this 2 year period [between 4.04 +/- 0.52 mmol/l prior to the switch and 3.90 +/- 0.63 mmol/l 2 years after the switch (p = 0.06)]. Of the 108 patients switched from losartan to candesartan, 94 are still registered at the practice and taking an angiotensin receptor blocker (ARB), 92 of these (98%) are still on candesartan and there was a significant reduction in blood pressure 2 years post-switch [between 138/79 +/- 12.9/6.6 prior to the switch and 131/77 +/- 13.1/7.6 mmHg 2 years after the switch (p<<0.05)]. No adverse events attributable to the switch were reported in either group.
Conclusion: This small study provides evidence that switching drugs in primary care can be cost effective and safe in the medium term, if care is taken with selection of patients and there is structured follow-up in place.