Description of genetic polymorphisms in CYP3A5 and MDR-1 and their impact on clinical acute rejection in liver transplant patients at Hospital San Vicente Fundación Rionegro.

Introduction. Tacrolimus is an immunosuppressive drug widely used in liver transplantation, which presents great interindividual variability, which is considered associated with the frequency of CYP3A5 and MDR-1 polymorphisms. The objective of this study was to evaluate the frequency of the rs776746, rs2032582 and rs1045642 polymorphisms and their association with clinical rejection and drug toxicity. Methods. Seventeen immunosuppressed patients with tacrolimus who underwent a liver transplant at the Hospital San Vicente Fundación Rionegro between 2020 and 2022 were included, with survival of more than one month. Clinical variables, acute rejection and pharmacological toxicity were evaluated. The study genes were sequenced by PCR, comparing their expression or not in each of the patients. Results. 43% of the patients were classified as CYP3A5*1/*1 and CYP3A5*1/*3, among which an association was found with increased rates of clinical acute rejection when compared with non-expressive patients (100% vs. 44%, p=0.05). There were no differences in drug toxicity or other outcomes. The rs2032582 polymorphism was found in 50% and rs1045642 in 23.5% of patients; however, no association with rejection or other clinical events was identified. Conclusions. An association was found between the CYP3A5*1/*1 and CYP3A5*1/*3 genotype and the clinical rejection rate. However, a larger sample is required to validate these data and propose models of personalized medicine. [ABSTRACT FROM AUTHOR]