Background: Transition to Dolutegravir (DTG)-based antiretroviral therapy (ART) may improve virological response (VR) in sub-Saharan Africa. Because VR may vary by age, understanding ART response across agerange may inform interventions on ART program. Our objective was to compare VR between children, adolescents and adults in the Cameroonian context. Methods: A comparative study was conducted from January 2021 to May 2022 amongst ART-experienced patients received at the Chantal BIYA International Reference Centre for HIV/AIDS prevention and management in Yaoundé-Cameroon for plasma viral load (PVL) monitoring. PVL was measured on Abbott m2000RT-PCR as per manufacturer's instructions. VR was defined as viral suppression (VL). Results: A total of 9034 patients, 72.8% female, were enrolled (8565 adults, 227 adolescents, 222 children); 1618 were on NNRTI-based, 299 on PIbased and 7118 on DTG based ART (82 children, 198 adolescents, 6824 adults). Median (IQR) duration on ART was 36 (27-39) months. Overall, VS was 89.9% (95% CI: 89.2-90.5) and 75.8% (95% CI 74.8-76.7) had achieved viral undetectability. By ART-regimen, VS on NNRTI-based, PI/r-based, and DTG-based therapy was respectively 86.5%, 60.2% and 91.8%. Conclusion: In the current ART program, nine out of ten Cameroonian patients achieve VS, with a superior efficacy of DTG-based ART (mainly adults). Nonetheless, male and pediatric populations have poorer rates of VS, especially for children below 10 years. Thus, scaling-up pediatric DTG-based ART, especially in children, would improve ART performance in similar African settings. [ABSTRACT FROM AUTHOR]