Abstract

Relationship between Efavirenz plasma concentrations and CYP2B6 Polymorphism in HIV/TB co-infected Africans taking rifampicin in the treatment Antituberculosis at Abidjan.

Ayoman Thierry-Lenoir Djadji*

Aim: To investigate polymorphisms cytochrome 2 B6 and concomitant rifampicin use on the plasma concentration of Efavirenz 600 mg vs. 800 mg on HIV-infected Ivoirians.
Methods: Consenting African patients with TB and HIV have received antiretroviral therapy including Efavirenz 600 and 800 mg, with rifampicin were observed. Efavirenz exposure was performed by HPLC MS-MS and Fluorimetric 5’ nuclease genotyping Assay (Atman Assays. Applied Biosystems Foster City, CA, USA) was used to genetic determination.
Results: 19 randomized patients undergone genotyping, the median age was 34 years [30-41], 09 (47%) of women, the median weight was 55 kg, with extremes [49-62], the rate basic of CD4 were 173/mm3 . The viral load was 6.10 log10 in basic (5.66 - 6.42), the Akan ethnic group was essential in our sample with 10 (52.65%), 04 (21.1%) patients were alcoholics. GG (47.370%), GT (31.58%) and TT (21.05%). Efavirenz 600 mg plasma concentration and genetic polymorphism showed no significative difference (P-value > 0.05). Also Efavirenz 800 Plasma concentration and genetic polymorphism showed no significative difference (P-value > 0.05). Therapeutic Drugs monitoring of Efavirenz 600 and 800 (Cmin, Cmax) in VIH/TB coinfected patients receiving Rifampicin stratified by CYP 2B6 c.516 ^T genotype during the time Week 4, Week 12, Week 24 by inter-series comparison don’t show any significant difference P value Kruskal Wallis > 0.05.
Conclusion: Our study showed that the polymorphism does not alter significantly the values of concentrations, even if they remain well above the normal value on Caucasian patients. Others studies should be conducted to better assess the real impact of polymorphism on the plasma concentrations of Efavirenz in black.