Gutierrez–Valencia A, et al. – This study was performed to evaluate the differential effect of different antiretroviral drug families on viral kinetics in seminal plasma (SP) of treatment–naive HIV–infected patients. In SP, both rilpivirine (RPV) and cobicistat–boosted elvitegravir (EVGcobi), associated to tenofovi–disoproxil fumarate (DF) and emtricitabine, behaved similarly and achieved an undetectable viral load much faster than ritonavir–boosted darunavir (DRVrtv).

Methods

• Phase II, randomized, open–label study was performed.
• Authors randomized the participants 1:1:1 to receive tenofovir–disoproxil fumarate (DF) plus emtricitabine, and either cobicistat–boosted elvitegravir (EVGcobi), rilpivirine (RPV), or ritonavir–boosted DRVrtv.
• The proportion of participants with undetectable HIV–RNA in SP at week 12 was observed as the primary endpoint.
• They measured HIV type 1 (HIV–1) RNA in paired SP and blood plasma (BP) at baseline and after 1, 2, 4, 6, 8, 12, 18, and 24 weeks.
• The liquid chromatography–tandem mass spectrometry method was used to quantify elvitegravir (EVG), RPV, and darunavir (DRV) concentrations.

Results

• In SP, the HIV–RNA decay rate with RPV was comparable to EVGcobi; by week 12, all participants in the RPV and the EVGcobi groups reached an undetectable viral load but only 58.3% in the DRVrtv arm (P = .003).
• In this study, the highest SP/BP drug concentration ratio was for EVG (0.43), followed–up by RPV (0.19), and DRV (0.10).
• For both EVG and RPV, the SP concentrations exceeded more than 2–fold the protein binding–adjusted EC90 for wild–type HIV–1; for DRV, only 33.7% of the SP indicated concentrations above the protein binding–adjusted EC90.