Does high-dose clopidogrel (150 mg) improve platelet inhibition compared to standard dose (75 mg) in post-PCI patients with CYP2C19 loss-of-function alleles?
Clopidogrel dose escalation to 150 mg daily significantly improves platelet inhibition in post-PCI patients identified with CYP2C19 loss-of-function alleles via outpatient screening.
This pilot study examined the feasibility of outpatient screening and clopidogrel dose adjustment for patients with previous percutaneous coronary intervention and at least one CYP2C19 loss-of-function allele. After screening a total of 211 outpatients, 50 patients were enrolled in a crossover study comparing 30 days of standard dose (75 mg) to 30 days of high-dose clopidogrel (150 mg). Platelet function was assessed with the VerifyNow P2Y12 assay. In patients with CYP2C19*2, 150 mg daily of clopidogrel was associated with improved ADP-specific platelet inhibition (217 vs 258 P2Y12 reaction units, p = 0.01). Outpatient screening for CYP2C19 loss-of-function polymorphisms is feasible, and a strategy of clopidogrel dose escalation may improve platelet inhibition in appropriately selected patients.
Rossi et al. (Thu,) studied this question.