Jo-Ann Passmore & Lindi Masson publish research in Nature Medicine

Associate Professor Jo-Ann Passmore and Dr Lindi Masson, both of the IDM and Division of Medical Virology, UCT, and their CAPRISA colleagues recently published exciting results in the journal Nature Medicine, from their research into genital inflammation affecting the effectiveness of tenofovir gel in preventing HIV acquisition in women. The research had its origins in a finding from Lindi’s doctoral work ten years ago.

Several clinical trials have demonstrated that antiretroviral (ARV) drugs taken as pre-exposure prophylaxis (PrEP) can prevent HIV infection, with the magnitude of protection ranging from -49% to 86%. Although these divergent outcomes are thought to be due primarily to differences in product adherence, biological factors likely contribute. Despite selective recruitment of higher-risk participants for prevention trials, HIV risk is heterogeneous even within higher-risk groups. To determine whether this heterogeneity could influence patient outcomes following PrEP, they undertook a post hoc prospective analysis of results from the CAPRISA 004 trial for 1% tenofovir gel (n = 774 patients), one of the first trials to demonstrate protection against HIV infection.

In women without genital inflammation, tenofovir was 57% protective against HIV but was 3% protective if genital inflammation was present. Among women who highly adhered to the gel, tenofovir protection was 75% in women without inflammation compared to -10% in women with inflammation.

They concluded that immunological predictors of HIV risk may modify the effectiveness of tools for HIV prevention; and by reducing genital inflammation in women, HIV prevention efforts may be augmented.

Full article:
"Genital inflammation undermines the effectiveness of tenofovir gel in preventing HIV acquisition in women" (2018). McKinnon LR, Liebenberg LJ, Yende-Zuma N, Archary D, Ngcapu S, Sivro A, Nagelkerke N, Garcia Lerma JG, Kashuba AD, Masson L, Mansoor LE, Karim QA, Karim SSA, Passmore JS.  Nature Medicine, http://www.nature.com/articles/nm.4506