Discussion
DECAY
This is the first controlled, randomized study to compare HIV-1-RNA decay in the SP of treatment-naive PLWH who started dolutegravir-based triple therapy versus dolutegravir plus lamivudine. As in other studies, BP HIV-1-RNA was higher than SP HIV-1-RNA, showing a discrete correlation between both compartments at baseline.Our results are consistent with those of clinical trials that have shown a similar viral load kinetics decay in BP with dolutegravir plus tenofovir disoproxil fumarate and emtricitabine as with dolutegravir/lamivudine.Regarding the probable causes for this similitude, the concentrations of lamivudine in the male genital tract might be sufficient to provide the same effect as tenofovir plus emtricitabine. Lamivudine accumulates in the male genital tract with a median SP/BP of 9.1 to 14.8 and median SP/BP AUCOn the other hand, tenofovir disoproxil fumarate has a very good penetration into the male genital tract, with a median SP/BP exposure ratio of 2.24 to 5.1 and intracellular concentrations of tenofovir diphosphate (the active metabolite) 17.5-fold higher than in BP.Previously, seven studies with a single treatment arm have analysed the SP HIV-1-RNA decay from treatment-naive PLWH who started ART with an integrase strand transfer inhibitor (InSTI), five of them with dolutegravir, plus two nucleos(t)ide analogues, which results at Week 12 are shown in Table Studies analysing decay kinetics of HIV-1-RNA in SP with InSTI-based regimensBasal SP HIV-1-RNA expressed as median (IQR) median [range] logThe last-mentioned study showed the worst results, with 8/12 samples with detectable SP HIV-1-RNA at Week 12 but with a median of 35 copies/mL (IQR, undetectable to 93). In addition, Gianella Our study has some limitations. First, the sample size may be modest to obtain definitive conclusions; however, this is one with the largest sample size among the available studies. Second, the results are only applicable to men and not to women. However, it is expected that they are also relevant to women since the rate of HIV excretion in genital secretions and the viral load is usually lower than in men.In conclusion, there are no clinical differences in the decay kinetics of SP HIV-1-RNA in treatment-naive PLWH who started dolutegravir/lamivudine compared with DTG + TAF/FTC. After 12 weeks of treatment, all participants had an undetectable HIV-1-RNA or less than 200 copies/mL in SP. These results and the information in the available literature suggest that condomless sex may be safe after 12 weeks of treatment with the new InSTIs.