High Frequency of CYP2C19*3 Heterozygotes Among Patients Under Clopidogrel Treatment in Ouagadougou, Burkina Faso.

<b>Background and Objective:</b> Despite its widespread use in cardiology, patient's response to clopidogrel exhibits significant interindividual variability, often leading to persistent thromboembolic complications. The hepatic Cytochrome P450 2C19 (CYP2C19) superfamily plays a pivotal role in clopidogrel's conversion to its active form and CYP2C19 polymorphisms significantly contribute to this variability. This study aimed to evaluate the prevalence and impact of the CYP2C19 rs4986893 polymorphism on clopidogrel treatment response. <b>Materials and Methods:</b> Seventy-three patients with Cardiovascular Diseases (CVD) undergoing clopidogrel antiplatelet therapy for a minimum of six months were recruited from Centre Hospitalier Universitaire Yalgado Ouédraogo (CHU-YO). Sociodemographic data were collected and DNA was extracted from blood samples for CYP2C19 rs4986893 genotyping using PCR-RFLP. <b>Results:</b> The patient's mean age was 62.56±13.45 years, ranging from 23 to 94 years, with a male-to-female sex ratio of 1.28. Most patients came from the informal sector, primarily of Mossi ethnicity and residing in Ouagadougou. Acute coronary syndromes (ACS) and hypertension were the predominant reasons for consultation, with clopidogrel showing efficacy in 97.3% of cases. While 72.6% had no family history of CVD, hypertension was prevalent among those with familial cardiovascular conditions. Genetic analysis revealed a 65.8% frequency of heterozygotes CYP2C19*1/*3, with no mutant homozygotes CYP2C19*3/*3 detected. The results of the present study underscore a high prevalence of heterozygotes CYP2C19*1/*3 among patients with cardiovascular diseases. <b>Conclusion:</b> This intermediate metabolic phenotype, along with a good response to clopidogrel, suggests that CYP2C19*1/*3 genotype promotes a favourable response to clopidogrel therapy.