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

Abstract

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 log10 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.