Measures to enhance angiotensin-receptor blocker prescribing efficiency in Belgium following generic losartan: impact and implications for the future

Compare the utilisation of losartan before and after the availability of generics in Belgium and its inclusion in the reference price system, which changed its reimbursement status. Determine the impact of reforms on expenditure/defined daily dose (DDD) for losartan and overall reimbursed expenditure for the angiotensin-receptor blockers (ARBs). Interrupted time-series analysis of monthly reimbursed prescriptions was used for all patients in Belgium covered by the social health insurance system prescribed an ARB alone or in combination between January 2007 and August 2011; that is, 42 months before generic losartan was included in the reference price system (July 2010) to 13 months after. A significant increase in losartan utilisation was seen following its change in reimbursement status whereas all other ARBs still required prior approval for reimbursement. Losartan utilisation increased from 18% of all single ARBs on a moving annual total (MAT) DDD basis just before the inclusion of losartan in the reference price system to 24% on a MAT basis 12 months after this. During this period, total ARB utilisation increased by 1%, consequently representing both new and switched patients. Reimbursed expenditure for losartan decreased 40% 12 months after its inclusion in the reference price system despite a 22% increase in utilisation. Total ARB expenditure reduced by 15% during this period. The reforms, including altering the prescribing regulations for losartan, significantly enhanced its utilisation, reduced its expenditure/DDD and reduced overall ARB expenditure in Belgium. No further measures are suggested for Belgium with more ARBs losing or about to lose their patents. There has been no change in the utilisation patterns of losartan in countries following generic availability where there are no specific demand-side measures. These findings confirm that multiple measures are needed to change physician prescribing patterns.