HIV-2 infection in Senegal: virological failures and resistance to antiretroviral drugs (ARVs)

Introduction: HIV-2, endemic in West Africa, has a natural resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs) which makes it difficult to treat it in developing countries. Methods: we conducted a descriptive, longitudinal, prospective study over the period November 2005-June 2017. Virologic failure has been defined as any viral load greater than 50 copies/ml after 6 months of ARV treatment administered twice. Assays for detecting drug-resistance mutations was performed in the protease-coding region and in the reverse transcriptase-coding region. Results: data from a total of 110 patients were collected, The patients had a median age of 46 years (ranging from 18 to 67) with a sex-ratio F/M of 2.54. At inclusion, viral load could be assessed in 44% of cases with a median of 935cp/ml (ranging from 17 to 144038). Antiretroviral regimen consisted of a combination of 2 NRTIs and 1IP in 94% of cases. The median follow-up was 1200 days (ranging from 1 to 3840); 94 then 76 patients completed their 12-month and 24-month assessments respectively. At 24-month follow-up, 39 patients had virologic failure, reflecting a prevalence of 39% estimated at 33% at 12-month follow-up and at 11% at 24-month follow-up; NRTIs resistance was observed in 45% of patients, IP resistance in 41% of patients while multi-NRTIs resistance and multi-IP resistance in 30% of patients. Conclusion: currently, there is an urgent need to make available the new therapeutic classes of ARV for second line ART for patients living with HIV-2 with therapeutic failure in resource-limited settings.