Virological, weight, and drug resistance outcomes among patients initiating a dolutegravir-based first-line antiretroviral therapy regimen in Zimbabwe.

OBJECTIVE: Dolutegravir (DTG)-based antiretroviral therapy (ART) is being scaled up in Africa. However, clinical experience with DTG and patterns of HIV drug resistance (HIVDR) are sparse in Zimbabwe. We assessed virological, weight, and HIVDR outcomes among individuals initiating on a DTG-based ART. DESIGN: We conducted a prospective cohort study among HIV-infected adult (≥18 years old) individuals attending care at Parirenyatwa hospital, Harare, Zimbabwe between October 2021 and April 2023. METHODS: Viral load and weight were assessed at both baseline and follow-up (≥24weeks) visits. HIVDR genotyping was performed by Sanger sequencing among participants with virological failure (viral load ≥1000 copies/ml) at follow-up visit. Factors associated with weight gain were determined using logistic regression analysis on STATA 17.0. RESULTS: One hundred and seventy-two participants were enrolled in the study. The median [interquartile range (IQR) age was 39 (29-48)] years whilst the median (IQR) CD4 + cell count and log 10 viral load at enrolment was 175 (58-328) cells/µl and 5.41 (4.80-5.74), respectively. After a median (IQR) duration of 27 (25-30) weeks on DTG, of the 131 participants with follow-up viral load data available, 129 (98%) had viral load less than 1000 copies/ml and among the 2 (2%) participants with viral load at least 1000 copies/ml, no emergent HIVDR was detected. We observed a significant increase in weight among the participants. The average weight gain was 5.25 kgs ( P  < 0.0001). Baseline CD4 + cell count at least 200 cells/µl was significantly associated with at a smaller weight gain [odds ratio (OR) = 0.26; 95% confidence interval (CI) 0.12-0.58, P  = 0.001]. CONCLUSION: We found high virological suppression and an increased weight among people initiating on DTG in a resource-limited setting. Encouragingly, HIVDR to DTG remains rare.

Clinic-based SAMBA-II vs centralized laboratory viral load assays among HIV-1 infected children, adolescents and young adults in rural Zimbabwe: A randomized controlled trial.

BACKGROUND: In Zimbabwe, children, adolescents and young adults living with HIV (CALWH) who are on public health antiretroviral therapy (ART) have inadequate viral load (VL) suppression. We assessed whether a clinic-based VL monitoring could decrease 12-month virologic failure rates among these CALWH. METHODS: The study was registered on ClinicalTrials.gov: NCT03986099. CALWH in care at Chidamoyo Christian Hospital (CCH) and 8 rural outreach sites (ROS) on long-term community-based ART were randomized (1:1) to 6 monthly VL monitoring by COBAS®Ampliprep®/Taqman48® HIV-1 at the provincial referral laboratory (PRL) as per standard of care (SOC) or by the clinic-based SAMBA II assay, Diagnostics for the Real World, at CCH. VL suppression, turn-around-time (TAT) for VL results, drug switching and drug resistance in second-line failure were assessed at 12 months. RESULTS: Of 390 CALWH enrolled 347 (89%) completed 12 months follow-up. Median (IQR) age and ART duration were 14.1 (9.7-18.2) and 6.4 (3.7-7.9) years, respectively. Over half (57%) of the participants were female. At enrolment, 78 (20%) had VL ≥1,000 copies/ml and VL suppression of 80% was unchanged after 12 months, with no significant difference between the SOC (81%) and the clinic-based (80%) arms (p = 0.528). Median (IQR) months to confirmatory VL result at CCH vs PRL was 4.0 (2.1-4.4) vs 4.5 (3.5-6.3) respectively; p = 0.027 at 12 months. Drug switching was documented among 26/347 (7%) participants with no difference between the median (IQR) time to switch in SOC vs clinic-based arms (5.1 (3.9-10.0) months vs 4.4 (2.5-8.4) respectively; p = 0.569). Out of 24 confirmed second-line failures, only 4/19 (21%) had protease inhibitor resistance. CONCLUSION: In rural Zimbabwe, the clinic-based SAMBA II assay was able to provide confirmatory VL results faster than the SOC VL assay at the PRL. However, this rapid TAT did not allow for a more efficient drug switch among these CALWH.

Tenofovir, Lamivudine, and Dolutegravir Among Rural Adolescents in Zimbabwe: A Cautionary Tale.

Tenofovir disoproxil fumarate, lamivudine, and dolutegravir (TLD) as a safe and more effective single daily dose regimen is rolling out in Africa for people living with HIV. Although access to viral load (VL) testing is improving, patients may still be transitioned to TLD with virological failure and potential drug resistance. We reviewed annual VL test results of 390 children and adolescents who had enrolled in a community-based antiretroviral therapy program in rural Zimbabwe between 2018 and 2019. VL testing was done by the near point of care simplified amplification-based assays (Diagnostics for the Real World, Sunnyvale, CA, USA) at Chidamoyo Christian Hospital and rate of virological suppression (VS) on TLD (VL <1,000 copies/mL) was assessed. Overall, 184 children and adolescents on TLD were enrolled in this study. The median [interquartile range (IQR)] age was 15 (11-19) years, above half of the participants were female (57%). Before switching to TLD, rate of VS was 76% (139/184). After a median (IQR) duration of 6.9 (5.5-9.1) months on TLD, VS was observed in 95% (174/184) of the participants. Of the 10 participants with VL ≥1,000 copies/mL on TLD, 90% (9/10) were failing on their previous regimens, 6 of 9 (67%) having been on boosted protease inhibitor-based regimens. A high rate (95%) of VS was observed among children and adolescents on TLD in rural Zimbabwe. TLD may address the problems of virological failure and emergence of resistance in Africa. However, longer follow-up might be needed to ascertain sustained VS in this vulnerable population. Randomized Control Trial NCT03986099.

Viral load care of HIV-1 infected children and adolescents: A longitudinal study in rural Zimbabwe.

INTRODUCTION: Maintaining virologic suppression of children and adolescents on ART in rural communities in sub-Saharan Africa is challenging. We explored switching drug regimens to protease inhibitor (PI) based treatment and reducing nevirapine and zidovudine use in a differentiated community service delivery model in rural Zimbabwe. METHODS: From 2016 through 2018, we followed 306 children and adolescents on ART in Hurungwe, Zimbabwe at Chidamoyo Christian Hospital, which provides compact ART regimens at 8 dispersed rural community outreach sites. Viral load testing was performed (2016) by Roche and at follow-up (2018) by a point of care viral load assay. Virologic failure was defined as viral load ≥1,000 copies/ml. A logistic regression model which included demographics, treatment regimens and caregiver's characteristics was used to assess risks for virologic failure and loss to follow-up (LTFU). RESULTS: At baseline in 2016, 296 of 306 children and adolescents (97%) were on first-line ART, and only 10 were receiving a PI-based regimen. The median age was 12 years (IQR 8-15) and 55% were female. Two hundred and nine (68%) had viral load suppression (<1,000 copies/ml) and 97(32%) were unsuppressed (viral load ≥1000). At follow-up in 2018, 42/306 (14%) were either transferred 23 (7%) or LTFU 17 (6%) and 2 had died. In 2018, of the 264 retained in care, 107/264 (41%), had been switched to second-line, ritonavir-boosted PI with abacavir as a new nucleotide analog reverse transcriptase inhibitor (NRTI). Overall viral load suppression increased from 68% in 2016 to 81% in 2018 (P<0.001). CONCLUSION: Viral load testing, and switching to second-line, ritonavir-boosted PI with abacavir significantly increased virologic suppression among HIV-infected children and adolescents in rural Zimbabwe.

Drug Resistance Among Adolescents and Young Adults with Virologic Failure of First-Line Antiretroviral Therapy and Response to Second-Line Treatment.

Barriers to sustainable virologic suppression (VS) of HIV-infected adolescents and young adults include drug resistance mutations (DRMs) and limited treatment options, which may impact the outcome of second-line antiretroviral therapy (ART). We sequenced plasma viral RNA from 74 adolescents and young adults (16-24 years) failing first-line ART at Newlands Clinic, Zimbabwe between October 2015 and December 2016. We evaluated first-line nucleoside reverse transcriptase inhibitor (NRTI) susceptibility scores to first- and second-line regimens. Boosted protease inhibitor (bPI)-based ART was provided and viral load (VL) monitored for ≥48 weeks. Fisher's exact test was used to evaluate factors associated with VS on second-line regimens, defined as VL <1,000 copies/mL (VS1,000) or <50 copies/mL (VS50). The 74 participants on first-line ART had a median [interquartile range (IQR)] age of 18 (16-21) years and 42 (57%) were female. The mean (±standard deviation) duration on ART was 5.5 (±3.06) years and the median (IQR) log10 VL was 4.26 (3.78-4.83) copies/mL. After switching to a second-line PI regimen, 88% suppressed to <1,000 copies/mL and 76% to <50 copies/mL at ≥48 weeks. A new NRTI was associated with increased VS50 (p = .031). These 74 adolescents and young adults failing first-line ART demonstrated high levels (97%) of DRMs, despite enhanced adherence counseling. Switching to new NRTIs in second-line improved VS. With the widespread adoption of generic dolutegravir, lamivudine and tenofovir combinations in Africa, genotyping to determine NRTI susceptibility, may be warranted.