Prospects of HIV elimination among men who have sex with men: a systematic review of modeling studies

BackgroundDespite advances in HIV treatment and prevention, men who have sex with men (MSM) remain disproportionately affected by HIV worldwide. This systematic review summarizes the results of mathematical modeling studies that evaluated whether interventions might eliminate HIV in MSM populations by geographical setting, type of intervention(s), elimination definition, and model characteristics. MethodsWe searched Embase and PubMed for modeling studies published between July 1, 2016 and January 7, 2025. Studies were included if they used a dynamic model to assess the impact of interventions on HIV transmission among MSM. Data were extracted on article information, study population, interventions, elimination definitions, model type, model structure, and calibration. The studies were critically appraised by evaluating the comprehensiveness of their models in addressing elimination. FindingsOf the 3,250 identified records, 89 studies were included. MSM populations in only five of the eight Joint United Nations Programme on HIV/AIDS (UNAIDS) regions were modeled, with over half of the models considering MSM in the USA. Complex agent-based models (ABMs) were as common as simpler compartmental models overall, with ABMs more frequently used in Western and Central Europe and North America (WCENA), while compartmental models predominated elsewhere. Thirty-nine of the 89 studies defined elimination as reductions or thresholds in HIV incidence or prevalence, a reproduction number below one, or the elimination of racial disparities. Elimination was achieved in 36 out of 50 modeled scenarios, but the authors of only six of these 36 scenarios thought the interventions required to achieve elimination were feasible. The six feasible elimination scenarios were reported in compartmental models for few countries in Western Europe and Asia. Models in which elimination was achieved most commonly used a combination of interventions that included pre-exposure prophylaxis (PrEP) and/or test-and-treat, except in Africa, where PrEP was not included. InterpretationModeling efforts to understand HIV elimination prospects among MSM outside WCENA should be intensified. To enhance study comparability and for models to contribute effectively to public health policy, the use of an elimination definition based on an incidence threshold would be the most valuable. Furthermore, by identifying gaps in current studies, we recommend novel research directions for modeling to inform a coordinated global response for HIV elimination among MSM.