Monoclonal Antibodies to Reduce SARS CoV-2 Transmission and Mortality

To evaluate the role of anti-viral monoclonal antibodies (mAbs) in reducing SARS-CoV-2 transmission and mortality, an agent-based model was developed that accounted for social contacts, movement/travel, disease progression, and viral shedding. The model was calibrated to mortality from October 2020 and April 2021 (aggressive pandemic phase). The model also projected an extended outlook to estimate mortality during a less aggressive phase (April to August 2021).  Simulated scenarios evaluated mAbs for averting infections and deaths on top of vaccine and aggregated non-pharmaceutical interventions. mAbs were used as active treatment and as passive immunity for post-exposure prophylaxis (PEP). Rapid diagnostic testing paired with mAbs was evaluated as early Treatment-as-Prevention strategy. Sensitivity analyses determined impact of increasing mAb supply and vaccine rollout. Allocation of mAbs as PEP or targeting those ≥65 years provided the greatest incremental benefits, averting up to 17% and 41% more infections and deaths, respectively, than vaccine alone. Rapid testing for earlier diagnosis and mAb use amplified these benefits. The model was sensitive to mAb supply; doubling supply further reduced infections and mortality. mAbs continued to provide incremental benefits even as the proportion of the vaccinated population increased. Model projections estimated that ~42% of the expected deaths between April and August 2021 could be averted. Use of mAbs as early treatment and PEP on top of a vaccination program would substantially reduce SARS-CoV-2 transmission and mortality even as vaccination increases and overall mortality decreases. These results provide a template for informing public health policy for current and future pandemic preparedness.