Abstract 15474: Genetic Testing in patients with Acute Coronary Syndromes to Determine Optimal Anti-Platelet Strategy: a Cost Effective Analysis
Background: Prasugrel is effective at decreasing cardiovascular events compared to clopidogrel, but increases the risk of bleeding. In 2010, the FDA issued a black box warning to consider genetic testing in clopidogrel users. Our aims were to evaluate (1) the balance of potential benefits and harms and (2) the cost-effectiveness that would result from adopting a genotype-guided strategy of dual anti-platelet therapy following PCI for ACS vs. no testing strategies of prasugrel plus aspirin (prasugrel) or clopidogrel plus aspirin (clopidogrel).
Methods: A Markov state transition model was used to conduct a decision analysis and compare strategies. Probabilities of adverse outcomes were derived from TRITON-TIMI 38 trial. Event rates on clopidogrel for carriers of CYP2C19*2 vs. wild-type were derived from the TRITON genetic substudy and a recent meta-analysis. Costs are expressed in January 2011 US dollars and estimated based on Medicare reimbursements for diagnosis-related group codes. Medication costs were used from the net wholesale price for prasugrel ($5.45/d) and a generic estimate for clopidogrel ($1/d).
Results: In base case analyses, the genetic testing guided strategy yielded more benefits than harms, and was less costly compared to both “no testing” strategies. Over 15 months, total costs were $83.8 ($1200.9 at 10 yrs) lower with a gain of 0.0007 QALY (0.0216 QALY at 10 yrs) in the genotype-guided strategy compared to prasugrel. Compared to clopidogrel, it was $0.38 ($2168.8 at 10 yrs) lower with a gain of 0.0036 QALY (0.112 QALY at 10 yrs). The strongest predictor of the preferred strategy was the relative risk (RR) of a thrombotic event occurring in CYP2C19*2 carriers versus wild-type. Below a RR of 1.5, a genotype-guided strategy is no longer more effective (but is less expensive) when compared to prasugrel. Compared to clopidogrel, below a RR of 1.3 a genotype-guided strategy is no longer cost effective (>$100,000/QALY). Clopidogrel costs ($1-$4/d) did not alter our results.
Conclusions: Among ACS patients undergoing PCI, a genotype-guided strategy is economically favorable in determining which anti-platelet regimen is used, assuming that the risk of thrombotic events in CYP2C19*2 carriers is approximately 30-50% higher than wild type patients.
- © 2011 by American Heart Association, Inc.