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

Abstract

Background Despite advances in HIV treatment and prevention, men who have sex with men (MSM) remain 3 disproportionately affected by HIV worldwide. This systematic review summarizes the results of mathematical 4 modeling studies that evaluated whether interventions might eliminate HIV in MSM populations by geographical 5 setting, type of intervention(s), elimination definition, and model characteristics. 6 Methods We searched Embase and PubMed for modeling studies published between July 1, 2016 and August 7 7, 2023. Studies were included if they used a dynamic model to assess the impact of interventions on HIV trans8 mission among MSM. Data were extracted on article information, study population, interventions, elimination 9 definitions, model type, model structure, and calibration. The studies were critically appraised by evaluating 10 the comprehensiveness of their models in addressing elimination. 11 Findings Of the 2,732 identified records, 80 studies were included. MSM populations in only five of the eight 12 Joint United Nations Programme on HIV/AIDS (UNAIDS) regions were modeled, with over half of the models 13 considering MSM in the USA. Complex agent-based models were the most common overall, while simpler com14 partmental models predominated outside Western and Central Europe and North America. Thirty-five of the 80 15 studies defined elimination as reductions or thresholds in HIV incidence or prevalence, a reproduction number 16 below one, or the elimination of racial disparities. Elimination was achieved in 32 out of 44 modeled scenar17 ios, but the authors of only six of these 32 scenarios thought the interventions required to achieve elimination 18 were feasible. The six feasible elimination scenarios were reported in compartmental models for few countries 19 in Western Europe and Asia. Models in which elimination was achieved most commonly used a combination 20 of interventions that included pre-exposure prophylaxis (PrEP) and/or test-and-treat, except in Africa, where 21 PrEP was not included. 22 Interpretation Modeling efforts to understand HIV elimination prospects among MSM outside Western and 23 Central Europe and North America should be intensified. Various definitions of elimination reflect perspectives 24 from both modeling and public health. To enhance study comparability and for models to contribute effectively 25 to public health policy, the use of an elimination definition based on an incidence threshold would be the most 26 valuable. Furthermore, by identifying gaps in current studies, we recommend novel research directions for mod27 eling to inform a coordinated global response for HIV elimination among MSM. 28 Funding Aidsfonds, EU.