ABSTRACT NUMBER: ESOC2026A2331 PRECISION STROKE SECONDARY PREVENTION USING CYP2C19 GENOTYPE POINT-OF-CARE TESTING

Abstract Background and aims Clopidogrel is a widely used drug for stroke secondary prevention following ischemic stroke and TIA. Over 25 % of the population is resistant to Clopidogrel due to reduced CYP2C19 enzyme activity. It makes Clopidogrel less effective or completely ineffective for secondary prevention. Rapid point-of-care testing (POCT) of Clopidogrel resistance identifies patients who need an alternative tailored treatment. Methods CYP2C19 POCT was initially implemented for a group of following patients before starting or already on stroke secondary prevention with Clopidogrel: POCT was performed from March 2025 to January 2026. To detect the six most common alleles (*2, *3, *4, *8, *17 and *35) the Genedrive System was used. Based on the CYP2C19 genotype, patients were classified as normal, rapid, ultra-rapid, intermediate and poor metabolizers. Multidisciplinary team discussed the genotype results, metabolism, likely phenotype, implications of the results and made recommendations for further personalized management. Results A total of 76 patients were tested. The cohort included 34 young stroke patients (45 %). 26 Normal metabolisers (*1/*1), 18 rapid (*1/*17), 3 ultra-rapid (*17/*17), 21 intermediate (*1/*2, *2/*17), and 8 poor (*2/*2) metabolizers were detected. 29 patients (38 %), intermediate and poor metabolisers, required a change to alternative tailored stroke secondary prevention. 19 of these patients were started on Ticagrelor as an alternative. Conclusions CYP2C19 POCT is a fast and efficient method for precise stroke secondary prevention. Conflict of interest Nothing to disclose