Emergence of NNRTI drug resistance mutations after single-dose nevirapine exposure in HIV type 1 subtype C-infected infants in India.

A feasibility study for providing single-dose nevirapine (SD-NVP) prophylaxis for prevention of mother-to-child transmission (PMTCT) of HIV infection provided an opportunity to study the emergence of nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance mutations as a result of single-dose administration. The study aimed at the detection of NNRTI drug resistance mutations arising as a result of SD-NVP. A total of 19 and 13 samples collected at 48 h and 2 months postpartum, respectively, from infants that were given SD-NVP were studied for the presence of NNRTI drug resistance mutations by PCR amplification and sequencing of the HIV-1 pol gene using HIV proviral DNA. The drug resistance mutational analysis of final sequences was carried out using the Stanford University HIV Drug Resistance database (http://hivdb.stanford.edu/hiv). Mutations associated with NNRTI drug resistance were observed in two (10.5%) and six (46.15%) samples at 48 h and at 2 months, respectively. K103N, one of the most common mutations, was not observed in any of the samples. The emergence of NVP resistance must be weighed against the simplicity, efficacy, and cost effectiveness of SD-NVP prophylaxis in PMTCT settings in developing countries.