Genotypic correlation of a virologic response to lamivudine, stavudine and nevirapine in patients for whom combination therapy had failed

Resistance is the consequence of mutations that emerge in the viral proteins targeted by antiretroviral agents. Thus, we focused our attention on mutations in HIV-1 reverse transcriptase to define their association with specific NRTIs and NRTI resistance mutations at therapeutic failure.Patients and The study population included 5 Iranian HIV-positive patients referring to Counseling Behavioral Modification Center in Shiraz who received a combination of antiretroviral therapy (lamivudine, stavudine and nevirapine). PBMC DNA was isolated from blood and PCR was performed to produce a 1200 bp amplicon andresolved by electrophoresis on a 0.7% agarose TBE gel, visualized with ethidium bromide. PCR products from HIV-1- infected patients were cloned into pCR2.1TOPO, then sequenced. Finally, sequence data were analyzed. Results showed drug resistance in 2 patients, of whom one had NNRTI resistance mutations (M230G, L234R and K238H) and other had both NRTI (V75M) and NNRTI (F227L) resistance mutations. Confirmation of genetic resistance in HIV-positive patients who show therapy failure can help physicians to change their drug regime in order to achieve better outcome.