Prevalence of pretreatment HIV-1 resistance to integrase strand transfer inhibitors in newly diagnosed and antiretroviral therapy-naive adults in Benin, West Africa.

OBJECTIVE

To evaluate the prevalence of pretreatment HIV-1 resistance to integrase inhibitors in newly diagnosed patients in the general population prior to commencement of the dolutegravir era as the first-line treatment regimen in Benin.

METHODS

This retrospective study employed samples described in the 2020 study by Tchiakpe and colleagues. Genotyping was carried out using both Agence nationale de recherches sur le Sida or National AIDS Research Agency (ANRS) and Applied Biosystems (Foster City, California, USA) HIV-1 Genotyping Kit PR/RT with integrase technologies. Sequences were used for viral subtype assignment and identification of resistance mutation positions using the Stanford algorithm.

RESULTS

A total of 161 samples were correctly sequenced. The predominant HIV-1 strain isolated was CRF02_AG (118/161; 73.3%), with 4/161 (2.5%) and 21/161 (13%) patients carrying at least one drug resistance mutation associated with PIs (1/161; 0.6%), NRTIs (1/161; 0.6%), non-nucleoside reverse transcriptase inhibitors (1/161; 0.6%) and NRTIs+NNRTIs (1/161; 0.6%) on the entire protease plus part of the reverse transcriptase and one accessory integrase strand transfer inhibitor (INSTI)-associated resistance mutation, respectively. Resistance mutations associated with the protease plus part of the reverse transcriptase-I85V, K103N, M184V, and M41L-were observed in proportions of 1/161 (0.6%), 2/161 (1.2%), 1/161 (0.6%), and 1/161 (0.6%), respectively. One patient (0.6%) carried both mutations (M41L and K103N). Among the INSTI-associated resistance mutations, E157Q represented 16/161 (9.9%), followed by T97A at 2/161 (1.2%) and 1/161 (0.6%) of each H51Y, D232N, and Q95K mutation. No major INSTI-associated mutations were found.

CONCLUSIONS

The prevalence of pretreatment HIV-1 resistance to integrase in this study was zero. This study reinforces the World Health Organization vision of improving patient outcomes by introducing INSTIs as first-line treatment regimens.