Impact of increased uptake of long-acting injectable antiretroviral therapy on HIV incidence and viral suppression in the United States under 2021 FDA guidelines

Objectives: To determine the impact of increased long-acting injectable antiretroviral therapy (Cabotegravir-rilpivirine [CAB/RPV]) use among persons with diagnosed HIV (PWDH) with viral suppression (VLS), per 2021 US Food and Drug Administration (FDA) guidelines, on HIV incidence and levels of VLS in the US. Methods: We used the HOPE compartmental model to simulate CAB/RPV use during 2023-2035. We first simulated a baseline scenario (no CAB/RPV), in which 69% of PWDH had VLS. We then introduced CAB/RPV in 2023 under two scenarios: (1) where CAB/RPV improved the duration of VLS post-cessation of ART use compared to oral ART; (2) where CAB/RPV additionally improved adherence. We compared cumulative 2023-35 incidence and percentage of PWDH with VLS at year-end 2035 to baseline. Results: When CAB/RPV increased the duration of VLS only, cumulative incidence was reduced up to 9%, and VLS increased up to 4%. When CAB/RPV also improved ART adherence, incidence was reduced up to 19.5%, and VLS increased up to 9%. Conclusions: CAB/RPV, even if only used among PWDH with VLS, may reduce HIV incidence and increase VLS, due to longer-lasting VLS post-cessation of usage. If CAB/RPV also improves ART adherence, incidence is further reduced. Improved clinical efficacy of CAB/RPV may translate to improved population-level outcomes, even in limited use cases.