HIV-1 Genital Shedding in HIV-infected Patients Randomized to Second-line Lopinavir/ritonavir Monotherapy Versus Tenofovir/lamivudine/lopinavir/ritonavir

Background: HIV-1 shedding in genital secretions is associated with HIV transmission risk. Limited data exist on the effect of second-line lopinavir/ritonavir monotherapy (mLPV/r) on genital secretion of HIV RNA.

Methods: We measured HIV-1 in genital secretions of HIV-infected adults at time of failure from non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimens and at 48 weeks after being randomized to second-line mLPV/r versus tenofovir/lamivudine/LPV/r (TDF/3TC/LPV/r). Plasma and genital secretion (semen, vaginal swab) HIV RNA was quantified by the CobasAmpliprep/TaqMan assay.

Results: Forty enrolled (15 on mLPV/r and 25 on TDF/3TC/LPV/r). Median age was 37.8 years and 35% were male. Median baseline CD4(+) T-cell count was 222 cells/mm(3), plasma HIV RNA was 4.1 log10 copies/ml and genital secretion HIV RNA was 2.3 log10 copies/ml. At week 48, the proportion of patients with plasma HIV RNA<50 copies/ml was 13/15 (87%) in mLPV/r and 21/25 (84%) in TDF/3TC/LPV/r arms. Median genital HIV RNA was significantly decreased from baseline in both arms (P=0.009 in mLPV/r and P=0.001 in TDF/3TC/LPV/r). In subjects with suppressed plasma HIV RNA, 12/34 (35%; 6/13 [46%] in the mLPV/r and 6/21 [29%] in the TDF/3TC/LPV/r arms) had detectable HIV RNA (range 74-957 copies/ml) in the genital secretions (P=0.41). By multivariate analysis, the only predictor of having genital HIV RNA>50 copies/ml at week 48 was baseline genital secretion HIV RNA>50 copies/ml (P=0.049).

Conclusions: LPV/r either given alone or in combination with TDF/3TC as second-line treatment achieved high genital secretion HIV RNA suppression rate. Genital secretion HIV RNA remained detectable at low levels in one-third of patients with suppressed plasma viraemia.