The following is a summary of “Effectiveness of Clopidogrel vs Alternative P2Y₁₂ Inhibitors Based on the ABCD-GENE Score,” published in the April 2024 issue of Cardiology by Thomas et al. 

An ABCD-GENE (age, body mass index, chronic kidney disease, diabetes, and CYP2C19 genetic variants) score of 10 or more suggests that clopidogrel may be ineffective. However, its response to other treatments remains to be seen. 

Researchers conducted a retrospective study aiming to evaluate the ABCD-GENE score relation with clopidogrel’s effectiveness compared to other P2Y₁₂ inhibitors (like prasugrel or ticagrelor) after percutaneous coronary intervention (PCI).

They included 4,335 patients undergoing PCI, CYP2C19 genotyping, and P2Y_{1  2} inhibitor treatment. The primary aim of this study was to identify major atherothrombotic events (MAE) within one year after PCI. Cox regression assessed the event risk in patients treated with clopidogrel or alternative, adjusting for factors like their ABCD-GENE score and CYP2C19 loss-of-function (LOF) genotype. 

The results showed that for patients with an ABCD-GENE score of less than 10 (n=3200), MAE was similar to alternative therapy vs. clopidogrel (weighted HR 0.89; 95% CI: 0.65-1.22, P = 0.475). The risk did not change significantly with treatment for those with scores ≥10 (n=1,135; weighted HR: 0.75, 95% CI: 0.51-1.11, P = 0.155). However, among CYP2C19 allele carriers, alternative therapy seemed to lower MAE risk in both the group with <10 (wHR: 0.50; 95% CI: 0.25-1.01; P=0.052), and group with score ≥10 (wHR 0.48, 95% CI: 0.29-0.80; P = 0.004), there was no difference in group with scores < 10 and no LOF alleles (wHR: 1.03; 95% CI: 0.70-1.51; P=0.885).

Investigators concluded that alternative therapy over clopidogrel in CYP2C19 LOF allele carriers after PCI is better to use regardless of their ABCD-GENE score. However, clopidogrel is as effective as alternative therapy in non-LOF patients with scores <10.

Source: jacc.org/doi/10.1016/j.jacc.2024.02.015