HIV Working Group

Di Shu, Ph.D. and Lan Wen, Ph.D.Research Fellows, Department of Population Medicine, Harvard Medical School”Estimating Population Level Effects of Interventions that Increase the Chance of Treatment in Low Treatment/High Risk Subgroups”ABSTRACT: Pre-exposure prophylaxis (PrEP) for HIV has been shown highly effective in preventing HIV in randomized controlled trials. Unfortunately, in practice some individuals with high background risk of HIV have had low treatment uptake. To date, most studies of the effect of PrEP on HIV incidence in the real-world have been based on mathematical models. Given limited uptake in certain high risk subgroups, effects of “always treat” versus “never treat” strategies are not well supported by real-world data, necessarily resulting in positivity violations. In this talk, we will present new causal parameters more appropriate for studying effects of real-world PrEP uptake which constitute special cases of effects of stochastic (random) dynamic strategies. These strategies shift the natural distribution of treatment dependent on individual characteristics. These interventions consider achievable changes in treatment practice which may still have large impacts on HIV incidence if appropriately targeted. Di will introduce background and the inverse probability weighted estimation method, and then Lan will cover the doubly robust estimation method. Event Url https://ems.sph.harvard.edu/MasterCalendar/EventDetails.aspx?data=hHr80o3M7J6wjV7YXU8EeEA5AmYx3nEsSWGnQUwhuQ%2fVAorxphWbyW0nAXXV9dNb