According to 2013 WHO guidelines, Tenofovir (TDF) is the preferred first-line regimen for adults and adolescents. 167 HIV-1 infected patients attaining immunological failure after TDF based first-line HAART were included in the study, RT region of HIV-1 pol gene was sequenced for them, IAS-USA 2014 list and Stanford HIV drug resistance database was used for mutation interpretation. REGA V3.0 was used of HIV subtyping. The predominant NRTI and NNRTI mutations observed were M184V (59.9%), K65R (28.1%), TAMs (29.3%) and K103NS (54.5%), V106AM (39.5%), Y181CIV (19.8%), respectively. Mutational association shows, K65R was negatively associated with TAMs (OR 0.31, p 0.008), M184V (OR 0.14, p 0.57) and K70E (OR 0.29, p 0.02). Genotypically predicted level of drug resistance based on mutation pattern shows 88% can be opted for AZT and still 65% can be opted for TDF. Considering the nature of K65R mutation in increasing susceptibility to AZT and its low prevalence, we conclude that in most patients failing TDF based first-line therapy; AZT can be considered for second-line ART regimen, followed by TDF itself.
Genotypic HIV-1 drug resistance among patients failing Tenofovir based first-line HAART in South India.