Long-term cost-effectiveness of clopidogrel in STEMI patients

BackgroundThe COMMIT trial demonstrated that clopidogrel produced a 9% relative reduction in death, reinfarction or stroke (9.2% vs. 10.1%, 95% CI: 0.86–0.97) in ST-elevated myocardial infarction (STEMI) patients.MethodsBetween 08/1999 and 05/2005, 45,852 STEMI patients were randomized to clopidogrel (n = 22,961) or matching placebo (n = 22,891) in addition to aspirin. The rate of initial hospitalizations for death, non-fatal myocardial infarction with/without major complications and PCI within 28 days was calculated based on the COMMIT clinical paper. Three CURE papers, concerning non-STEMI patients, were used to estimate the event rates between 29 days and 1 year. Hospitalizations were assigned a diagnosis-related group (DRG). Costs for each DRG were estimated from the Medicare reimbursement rate. Clopidogrel was assumed to be given for 1 year, priced at $4.22/day. Life expectancy gain as a result of the prevention of death, myocardial infarction, and stroke was estimated using Framingham data.ResultsWithin 28 days, adding clopidogrel to aspirin is likely a dominant strategy, lowering the event rate (9.2% vs. 10.1%) without an increase in cost ($7791 vs. $7797). Over a lifetime, treating for 1 year with clopidogrel-plus-aspirin produced a gain of 0.1187 life years at an incremental cost of $1269 compared to aspirin alone, resulting in an incremental cost-effectiveness ratio (ICER) of $10,691/life year gained. Sensitivity analyses showed that ICERs for clopidogrel are well below the common benchmark ceiling ratio of $50,000/life year gained.ConclusionsAddition of clopidogrel to aspirin, given up to 1 year, in the setting of STEMI is a highly cost-effective strategy.