Effect of Dolutegravir-Based First-Line Antiretroviral Therapy on Mother-to-Child Transmission of HIV Among HIV-Exposed Infants in Ethiopia: a Before-and-After Study

Background Currently, Dolutegravir (DTG)-based regimens are administered to women on Option B plus to prevent mother-to-child transmission (MTCT) of the virus. However, its effect on reducing MTCT of human immunodeficiency virus (HIV) among HIV-exposed infants over the previously used Efavirenz (EFV)-based regimen is unknown. Objective This study aimed to compare the effects of DTG-based and EFV-based regimens on the MTCT of HIV among HIV-exposed infants in Ethiopia. Methods An uncontrolled before-and-after study design was conducted among 958 mother-infant pairs (479 on EFV-based and 479 on DTG-based regimens) enrolled in the prevention of mother-to-child transmission (PMTCT) care from September 2015 to February 2023. The outcome variable was the HIV infection status among the exposed infants. A log-binomial model was employed, and the proportion was computed to compare the incidence of MTCT of HIV in both groups. The risk ratio (RR) with a 95% confidence interval (CI) was calculated to assess the predictor variables. Results Mothers on DTG-based regimens were approximately 44% (adjusted risk ratio (aRR): 0.56; 95% CI: 0.44, 0.70) less likely to transmit HIV to their infants than those on EFV-based regimens. In addition, poor or fair adherence to antiretroviral therapy (ART) (aRR: 5.82; 95% CI: 3.41, 9.93), home delivery (aRR: 3.61; 95% CI: 2.32, 5.62), mixed feeding practice (aRR: 1.83; 95% CI: 1.45, 2.3) and not receiving antiretroviral prophylaxis (aRR: 3.26; 95% CI: 1.6, 6.64) were found to increase the risk of MTCT of HIV infection, whereas older maternal age (aRR: 0.93; 95% CI: 0.9, 0.96) was a protective factor. Conclusion Mother-to-child transmission of HIV was less frequently observed in mother-infant pairs exposed to the DTG-based regimens as compared to those exposed to the EFV-based regimens. Thus, DTG-based first-line ART regimens supplementation should be sustained to achieve global and national targets for zero new infections in HIV-exposed infants.