Minority drug-resistant HIV-1 variants: transmission and response to antiretroviral therapy

The transmission of HIV-1 variants with resistance to antiretroviral therapy can impair response to first-line antiretroviral therapy. The current genotypic tests used for surveillance of HIV-1 resistance and routine management of antiretroviral therapy have a limit of sensitivity of approximately 20% of the bulk viral population for the detection of minority variants. Ultrasensitive genotypic techniques have been developed and are able to increase the detection of minority-resistant viruses in a significant proportion of antiretroviral-naive patients. De novo production and transmission of minority variants are discussed. Discordant results have been reported considering the clinical relevance of minority resistant variants and their impact on first-line therapy, which could be due to treatment regimens and the duration of infection.