Assessment of minority frequency pretreatment HIV drug-resistant variants in pregnant women and associations with virologic non-suppression at term.

OBJECTIVE: To assess in ART-naïve pregnant women randomized to efavirenz- versus raltegravir-based ART (IMPAACT P1081) whether pretreatment drug resistance (PDR) with minority frequency variants (<20% of individual's viral quasispecies) affects antiretroviral treatment (ART)-suppression at term. DESIGN: A case-control study design compared PDR minority variants in cases with virologic non-suppression (plasma HIV RNA >200 copies/mL) at delivery to randomly selected ART-suppressed controls. METHODS: HIV pol genotypes were derived from pretreatment plasma specimens by Illumina sequencing. Resistance mutations were assessed using the HIV Stanford Database, and the proportion of cases versus controls with PDR to their ART regimens was compared. RESULTS: PDR was observed in 7 participants (11.3%; 95% CI 4.7, 21.9) and did not differ between 21 cases and 41 controls (4.8% vs 14.6%, p = 0.4061). PDR detected only as minority variants was less common (3.2%; 95% CI 0.2, 11.7) and also did not differ between groups (0% vs. 4.9%; p = 0.5447). Cases' median plasma HIV RNA at delivery was 347c/mL, with most (n = 19/22) showing progressive diminution of viral load but not ≤200c/mL. Among cases with viral rebound (n = 3/22), none had PDR detected. Virologic non-suppression at term was associated with higher plasma HIV RNA at study entry (p<0.0001), a shorter duration of ART prior to delivery (p<0.0001), and randomization to efavirenz- (versus raltegravir-) based ART (p = 0.0085). CONCLUSIONS: We observed a moderate frequency of PDR that did not significantly contribute to virologic non-suppression at term. Rather, higher pretreatment plasma HIV RNA, randomization to efavirenz-based ART, and shorter duration of ART were associated with non-suppression. These findings support early prenatal care engagement of pregnant women and initiation of integrase inhibitor-based ART due to its association with more rapid suppression of plasma RNA levels. Furthermore, because minority variants appeared infrequent in ART-naïve pregnant women and inconsequential to ART-suppression, testing for minority variants may be unwarranted.

Brief Report: Vaginal Viral Shedding With Undetectable Plasma HIV Viral Load in Pregnant Women Receiving 2 Different Antiretroviral Regimens: A Randomized Clinical Trial.

BACKGROUND: Pregnant women using antiretrovirals (ARVs) may have persistent vaginal viral shedding, which could be associated with sexual and perinatal HIV transmission. However, there are scant data on vaginal viral load (VVL) in pregnant women with undetectable plasma viral load (PVL). METHODS: This study was a post hoc analysis of an open-label randomized trial to evaluate the virologic response of 2 ART regimens. The participants were ART-naive women living with HIV initiating ART regimens between 20 and 36 weeks of pregnancy recruited at 19 clinical sites in 6 countries. Participants were randomized to receive 400 mg of raltegravir 2 times a day or 600 mg of efavirenz 4 times a day in addition to 150 mg of lamivudine and 300 mg of zidovudine 2 times a day. VVL and PVL tests were performed at every study visit. The primary outcome measures were HIV-1 PVL and VVL at maternal study week 4 and rates of perinatal HIV transmission. RESULTS: A total of 408 were enrolled, of whom 323 had VVL samples 4 weeks after enrollment and were included in this analysis. Among women with undetectable/nonquantifiable PVL during ART, the overall rate of quantifiable VVL at week 4 was 2.54% (7/275). Of the 275 with nonquantifiable PVL, 99.1% (115/116) and 96.2% (153/159) had nonquantifiable VVL in the efavirenz and raltegravir arms, respectively. None of the 7 women with quantifiable VVL at the week 4 study visit transmitted HIV to their infants. CONCLUSIONS: Detectable VVL in pregnant women with undetectable/nonquantifiable PVL while receiving ART was rare and not associated with perinatal HIV transmission.

Raltegravir versus efavirenz in antiretroviral-naive pregnant women living with HIV (NICHD P1081): an open-label, randomised, controlled, phase 4 trial.

BACKGROUND: Although antiretroviral regimens containing integrase inhibitors rapidly suppress HIV viral load in non-pregnant adults, few published data from randomised controlled trials have compared the safety and efficacy of any integrase inhibitor to efavirenz when initiated during pregnancy. We compared safety and efficacy of antiretroviral therapy with either raltegravir or efavirenz in late pregnancy. METHODS: An open-label, randomised controlled trial was done at 19 hospitals and clinics in Argentina, Brazil, South Africa, Tanzania, Thailand, and the USA. Antiretroviral-naive pregnant women (20-<37 weeks gestation) living with HIV were assigned to antiretroviral regimens containing either raltegravir (400 mg twice daily) or efavirenz (600 mg each night) plus lamivudine 150 mg and zidovudine 300 mg twice daily (or approved alternative backbone regimen), using a web-based, permuted-block randomisation stratified by gestational age and backbone regimen. The primary efficacy outcome was plasma HIV viral load below 200 copies per mL at (or near) delivery. The primary efficacy analysis included all women with a viral load measurement at (or near) delivery who had viral load of at least 200 copies per mL before treatment and no genotypic resistance to any study drugs; secondary analyses eliminated these exclusion criteria. The primary safety analyses included all women who received study drug, and their infants. This trial is registered with Clinicaltrials.gov, number NCT01618305. FINDINGS: From Sep 5, 2013, to Dec 11, 2018, 408 women were enrolled (206 raltegravir, 202 efavirenz) and 394 delivered on-study (200 raltegravir, 194 efavirenz); 307 were included in the primary efficacy analysis (153 raltegravir, 154 efavirenz). 144 (94%) women in the raltegravir group and 129 (84%) in the efavirenz group met the primary efficacy outcome (absolute difference 10%, 95% CI 3-18; p=0·0015); the difference primarily occurred among women enrolling later in pregnancy (interaction p=0·040). Frequencies of severe or life-threatening adverse events were similar among mothers (30% in each group; 61 raltegravir, 59 efavirenz) and infants (25% in each group; 50 raltegravir, 48 efavirenz), with no treatment-related deaths. INTERPRETATION: Our findings support major guidelines. The integrase inhibitor dolutegravir is currently a preferred regimen for the prevention of perinatal HIV transmission with raltegravir recommended as a preferred or alternative integrase inhibitor for pregnant women living with HIV. FUNDING: Eunice Kennedy Shriver National Institute of Child Health and Human Development and National Institute of Allergy and Infectious Diseases.

Safety, Tolerability, and Pharmacokinetics of the Broadly Neutralizing Human Immunodeficiency Virus (HIV)-1 Monoclonal Antibody VRC01 in HIV-Exposed Newborn Infants.

BACKGROUND: Although mother-to-child human immunodeficiency virus (HIV) transmission has dramatically decreased with maternal antiretroviral therapy, breast milk transmission accounts for most of the 180 000 new infant HIV infections annually. Broadly neutralizing antibodies (bNAb) may further reduce transmission. METHODS: A Phase 1 safety and pharmacokinetic study was conducted: a single subcutaneous (SC) dose of 20 or 40 mg/kg (Dose Groups 1 and 2, respectively) of the bNAb VRC01 was administered to HIV-exposed infants soon after birth. Breastfeeding infants (Dose Group 3) received 40 mg/kg SC VRC01 after birth and then 20 mg/kg/dose SC monthly. All infants received appropriate antiretroviral prophylaxis. RESULTS: Forty infants were enrolled (21 in the United States, 19 in Africa). Subcutaneous VRC01 was safe and well tolerated with only mild-to-moderate local reactions, primarily erythema, which rapidly resolved. For multiple-dose infants, local reactions decreased with subsequent injections. VRC01 was rapidly absorbed after administration, with peak concentrations 1-6 days postdose. The 40 mg/kg dose resulted in 13 of 14 infants achieving the serum 50 micrograms (mcg)/mL target at day 28. Dose Group 3 infants maintained concentrations greater than 50 mcg/mL throughout breastfeeding. CONCLUSIONS: Subcutaneous VRC01 as single or multiple doses is safe and well tolerated in very young infants and is suitable for further study to prevent HIV transmission in infants.