OBJECTIVES: Budget impact models for new drugs provide estimates of the changes in annual costs of drug therapy as well as estimates in the changes in other health care costs attributable to the underlying disease or the side effects of treatment.
METHODS: In this study we estimated the annual change in disease and side-effects costs associated with the addition of prasugrel to a drug formulary for treatment of those with acute coronary syndrome (ACS) undergoing a percutaneous coronary intervention in a managed care organization with 1,000,000 covered lives. The model compared the annual costs in each of the first three years after addition of prasugrel to the formulary assuming a maximum treatment share of 50% after 1 year. The only alternative treatment was clopidogrel and people already being treated with clopidogrel were not switched to prasugrel. The relative risk of subsequent cardiovascular events and bleeding events for each drug were taken from a head-to-head 15-month clinical trial. The risk of cardiovascular events reverted to the risk of those taking only aspirin for those discontinuing prasugrel or clopidogrel treatment.
RESULTS: The estimated numbers of cardiovascular events (bleeding events) after an ACS episode with prasugrel on the formulary in the first three years were 541 (36), 528 (42), and 525 (43) respectively and without prasugrel were 548 (35) in all three years. The annual reductions in disease- and bleeding-related costs in the first 3 years after adding prasugrel to the formulary were estimated to be $141,907, $419,377, and $488,119 respectively.
CONCLUSIONS: Using a more effective dual oral antiplatelet regimen is likely to result in lower disease-related costs that are not offset by higher bleeding-related costs. The disease- and bleeding-event cost savings estimated in the model should be included in a comprehensive estimate of the budget impact of adding prasugrel to a formulary.
