Acquired HIV drug resistance and virologic monitoring in a HIV hyper-endemic setting in KwaZulu-Natal Province, South Africa.

BACKGROUND: Introduction of tenofovir (TDF) plus lamivudine (3TC) and dolutegravir (DTG) in first- and second-line HIV treatment regimens in South Africa warrants characterization of acquired HIV-1 drug resistance (ADR) mutations that could impact DTG-based antiretroviral therapy (ART). In this study, we sought to determine prevalence of ADR mutations and their potential impact on susceptibility to drugs used in combination with DTG among HIV-positive adults (≥ 18 years) accessing routine care at a selected ART facility in KwaZulu-Natal, South Africa. METHODS: We enrolled adult participants in a cross-sectional study between May and September 2019. Eligible participants had a most recent documented viral load (VL) ≥ 1000 copies/mL after at least 6 months on ART. We genotyped HIV-1 reverse transcriptase and protease genes by Sanger sequencing and assessed ADR. We characterized the effect of ADR mutations on the predicted susceptibility to drugs used in combination with DTG. RESULTS: From 143 participants enrolled, we obtained sequence data for 115 (80%), and 92.2% (95% CI 85.7-96.4) had ADR. The proportion with ADR was similar for participants on first-line ART (65/70, 92.9%, 95% CI 84.1-97.6) and those on second-line ART (40/44, 90.9%, 95% CI 78.3-97.5), and was present for the single participant on third-line ART. Approximately 89% (62/70) of those on first-line ART had dual class NRTI and NNRTI resistance and only six (13.6%) of those on second-line ART had major PI mutations. Most participants (82%) with first-line viraemia maintained susceptibility to Zidovudine (AZT), and the majority of them had lost susceptibility to TDF (71%) and 3TC (84%). Approximately two in every five TDF-treated individuals had thymidine analogue mutations (TAMs). CONCLUSIONS: Susceptibility to AZT among most participants with first-line viraemia suggests that a new second-line regimen of AZT + 3TC + DTG could be effective. However, atypical occurrence of TAMs in TDF-treated individuals suggests a less effective AZT + 3TC + DTG regimen in a subpopulation of patients. As most patients with first-line viraemia had at least low-level resistance to TDF and 3TC, identifying viraemia before switch to TDF + 3TC + DTG is important to avoid DTG functional monotherapy. These findings highlight a need for close monitoring of outcomes on new standardized treatment regimens.

High mortality rates in men initiated on anti-retroviral treatment in KwaZulu-Natal, South Africa.

In attaining UNAIDS targets of 90-90-90 to achieve epidemic control, understanding who the current utilizers of HIV treatment services are will inform efforts aimed at reaching those not being reached. A retrospective chart review of CAPRISA AIDS Treatment Program (CAT) patients between 2004 and 2013 was undertaken. Of the 4043 HIV-infected patients initiated on ART, 2586 (64.0%) were women. At ART initiation, men, compared to women, had significantly lower median CD4+ cell counts (113 vs 131 cells/mm3, p <0.001), lower median body mass index (BMI) (21.0 vs 24.2 kg/m2, p<0.001), higher mean log viral load (5.0 vs 4.9 copies/ml, p<0.001) and were significantly older (median age: 35 vs. 32 years, p<0.001). Men had higher mortality rates compared to women, 6.7 per 100 person-years (p-y), (95% CI: 5.8-7.8) vs. 4.4 per 100 p-y, (95% CI: 3.8-5.0); mortality rate ratio: 1.54, (95% CI: 1.27-1.87), p <0.001. Age-standardised mortality rate was 7.9 per 100 p-y (95% CI: 4.1-11.7) for men and 5.7 per 100 p-y (95% CI: 2.7 to 8.6) for women (standardised mortality ratio: 1.38 (1.15 to 1.70)). Mean CD4+ cell count increases post-ART initiation were lower in men at all follow-up time points. Men presented later in the course of their HIV disease for ART initiation with more advanced disease and experienced a higher mortality rate compared to women.