Prevalence of HIV drug resistance among adolescents receiving ART in Cameroon with low- or high-level viraemia.

OBJECTIVES: To characterize HIV drug resistance (HIVDR) below and above the WHO threshold of 1000 copies/mL, considered for the definition of HIV ART failure in resource-limited settings. METHODS: From a cohort of 280 adolescents (aged 10-19 years) receiving ART for at least 6 months, genotypic resistance testing (GRT) was attempted for two groups of participants: participants with low-level viraemia [LLV; viral load (VL) 200-999 copies/mL] and those in virological failure (VF; confirmed VL ≥1000 copies/mL) using an in-house method. The Stanford HIValg Program was used to identify relevant HIVDR mutations and predict the efficacy of the newly introduced tenofovir-lamivudine-dolutegravir combination. RESULTS: GRT was successfully performed in 54/58 (93.1%) eligible participants, of which 28/31 (90.3%) were in VF and 26/27 (96.3%) had LLV. A high level of resistance was found both in adolescents with LLV and those in VF, with respectively 84.6% (22/26) and 75.0% (21/28) of participants harbouring at least one HIVDR mutation. NRTIs and NNRTIs were the most affected drug classes in both population groups. In contrast, PIs were not significantly affected and dolutegravir was expected to be active for all participants tested. However, for the newly introduced dolutegravir-based combination, functional monotherapy (dolutegravir only) was potentially possible for 22.7% (5/22) of the participants with LLV. CONCLUSIONS: Our findings show that the 1000 copies/mL threshold is not an indicator of virological success and we call for a revision of the current WHO definition of VF in resource-limited countries.

Viral load suppression in HIV-infected adolescents in cameroon: towards achieving the UNAIDS 95% viral suppression target.

BACKGROUND: Achieving the UNAIDS 95% sustained viral suppression (VS) rate requires considerable global efforts, particularly among adolescents living with HIV (ALHIV) who are often associated with high rates of virological failure (VF). In this study, we prospectively assessed the rate of VS, and the factors associated with VF in a cohort of adolescents followed up according to the WHO guidelines in Cameroon. METHODS: A cross-sectional study was carried out in 2021 among adolescents (aged 10-19 years) receiving ART in the national program in Cameroon. Socio-demographic and clinical data were collected using patients' medical files and a brief interview with the participant and/or his guardian. Thereafter, a first viral load test (VL1) was performed using the ABBOTT Platform. For adolescents with VL1 > 1000 copies/ml, adherence-enhancing interventions were routinely performed each month for 3 consecutive months, after which a second viral load (VL2) was measured. Adolescents with VL2 > 1000 copies/ml were considered in VF. RESULTS: Overall, 280 adolescents were enrolled, of whom 89.3% (250/280) acquired HIV infection via mother-to-child transmission. The median age was 16.0 (IQR: 13.0-18.0) years and the median duration on ART was 9.8 (IQR: 5.1-12.8) years. Females and males were almost equally represented, as 52.1% (146/280) were female, while 47.9% (134/280) were males (p = 0.47). The VS rate was 88.2% (CI: 83.8-91.7%) overall; 89.0% (CI: 82.0-93.1%) and 88.7% (CI: 81.2-93.0%) in females and males, respectively. Being on second or third-line ART, self-declared suboptimal adherence, and a history of past VF were independently associated with VF. CONCLUSION: The high rate of VS we report in this study is welcome in the era of the 95/95/95 UNAIDS goals, and indicates that improving treatment outcomes in this specific and fragile population that represent adolescents in Sub-Saharan Africa is achievable. TRIAL REGISTRATION: 20/10/2020 NCT04593979 ( https://clinicaltrials.gov/ct2/show/NCT04593979 ).