Viral Kinetics in Semen With Different Antiretroviral Families in Treatment-Naive Human Immunodeficiency Virus-Infected Patients: A Randomized Trial

Background: There are several regimens for starting antiretroviral treatment, but it remains unknown whether either of them is more advantageous regarding the time course and magnitude of human immunodeficiency virus (HIV) RNA decay in semen.

Objective: To evaluate the differential effect of different antiretroviral drug families on viral kinetics in seminal plasma (SP) of treatment-naive HIV-infected patients.

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

Results: In SP, the HIV-RNA decay rate with RPV was as fast as with 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). 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 >2-fold the protein binding-adjusted EC90 for wild-type HIV-1; for DRV, only 33.7% of the SP showed concentrations above the protein binding-adjusted EC90.

Conclusions: In SP, both RPV and EVGcobi, associated to tenofovir-DF and emtricitabine, behave similarly and achieve an undetectable viral load much faster than DRVrtv.

Registration: European Medical Agency (No. EudraCT: 2014-001348-39).