IMPACT OF MULTIPLE SWITCHING ON HEALTH CARE COSTS AND OUTCOMES IN GENERIC DRUG POLICIES: THE HUNGARIAN CASE OF LOSARTAN

The objective of this study was to estimate the impact of multiple switching of generic antihypertensive therapy on health outcomes and total health expenditure in a retrospective analysis of payer's database. We included patients with hypertension from the National Health Insurance Fund database into our analysis who were treated with losartan or losartan/hydrochlorothiazide (HCT) in 12-month prior to patent expiry of losartan or losartan/HCT. We compared 3-year MACEs (major cardiovascular events, including stroke, myocardial infarct or death) and treatment costs (antihypertensive drugs, other cardiovascular drugs, cardiovascular treatments. non-cardiovascular interventions) from payer's perspective of those patients with multiple switching of generic drug therapy in 12-month after patent expiry (n = 3.280) with those patients who had been switched to a generic losartan or losartan/HCT brand after patent expiry (single switch) without any additional switching in 12-month {N = 3.101}. 9.8% of patients with single switch had MACEs over 36-month compared to 10.7% of patients in the multiple switch group (p = 0.247). Compared to baseline year the difference in total annual treatment costs were higher by (sic)461 in the multiple switch group than in the single switch group (p < 0.001). Further studies are needed to strengthen the evidence on the suboptimal consequences of multiple switching of generic drugs on health outcomes and total treatment costs compared to single switch.