Anca Buzoianu 1, Ioana Corina Bocşan 1, C. Maier 2, A.P. Trifa 3, R.A. Popp 3, L. Perju Dumbrava 4, O. Sabin 1, Claudia Militaru 1, E. Brusturean 4, Z.Z. Major 4, C. Popescu 5
1 Department of Clinical Pharmacology, “Iuliu Haţieganu” University of Medicine and Pharmacy, Cluj-Napoca, Romania
2 Department of Drug Analysing, Iuliu Haţieganu” University of Medicine and Pharmacy, Cluj-Napoca, Romania
3 Department of Genetics, Iuliu Haţieganu” University of Medicine and Pharmacy, Cluj-Napoca, Romania
4 Department of Neurology, Iuliu Haţieganu” University of Medicine and Pharmacy, Cluj-Napoca, Romania
5 Department of Psychiatry, Iuliu Haţieganu” University of Medicine and Pharmacy, Cluj-Napoca, Romania
Abstract
The aim of the study was to evaluate the influence of MDR1 C3435T polymorphisms on the bioavailability of valproic acid (VPA) and the correlation between the genotype and the plasma levels. Materials and method: 60 patients with epilepsy, with a mean age of 37.15±12.76, evaluated in the Neurology Clinic of Cluj-Napoca were included. All patients were under stable VPA treatment for at least a month. Steady state plasma concentrations were determined using the GC/FID technique. We considered therapeutic level between 50-100 μg/mL. Using the PCR-RFLP method for each patient we have determined allelic variant of MDR1 C3435T polymorphism. Results. 71.7% of the patients had therapeutic level of valproic acid, 13.3% supra-therapeutic and 15% sub-therapeutic level of VPA. 13.3 % of the patients present CC genotype, while 58.3% present CT genotype and 28.3% TT genotype. The mean VPA plasmatic level is lower in patients with CC genotype, but with no significance, compared with TT and CT genotypes. There was no significant correlation established between the presence of C3435T polymorphism and sub or supra-therapeutic level of VPA. Conclusions. The polymorphism of MDR1 gene has no influence on the VPA serum level.