Clinical Trials That Have Changed Clinical Practice and Care of Pregnant People With HIV.

Over the last 4 decades, significant advances in the care of HIV during pregnancy have successfully reduced, and nearly eliminated, the risk of perinatal HIV transmission. The baseline risk of transmission without intervention (25% to 30%) is now <1% to 2% in the United States with contemporary antepartum, intrapartum, and postnatal interventions. In this review, we discuss 3 landmark clinical trials that substantially altered obstetric practice for pregnant individuals with HIV and contributed to this extraordinary achievement: 1) the Pediatric AIDS Clinical Trials Group 076 Trial determined that antepartum and intrapartum administration of antiretroviral drug zidovudine to the pregnant individual, and postnatally to the newborn, could reduce the risk of perinatal transmission by approximately two-thirds; 2) the European Mode of Delivery Collaboration Trial demonstrated performance of a prelabor cesarean birth before rupture of membranes among pregnant people with viremia reduced the risk of perinatal transmission compared with vaginal birth; and 3) the International Maternal Pediatric Adolescent AIDS Clinical Trials Network 2010 Trial identified that dolutegravir-containing, compared with efavirenz-containing, antiretroviral regimens during pregnancy achieved a significantly higher rate of viral suppression at delivery with shorter time to viral suppression, with fewer adverse pregnancy outcomes. Collectively, these trials not only advanced obstetric practice but also advanced scientific understanding of the timing, mechanisms, and determinants of perinatal HIV transmission. For each trial, we will describe key aspects of the study protocol and outcomes, insights gleaned about the dynamics of perinatal transmission, how each study changed clinical practice, and relevant updates to current practice since the trial's publication.

Association of Fatty Acid Signatures with HIV Viremia in Pregnancy.

Omega-6 (n-6) and omega-3 (n-3) polyunsaturated fatty acids (PUFAs) are vital for fetal metabolic programming and immunomodulation. Higher n-6:n-3 ratios, reflecting a proinflammatory eicosanoid profile, are associated with adverse perinatal outcomes. Limited data exist, however, on n-6 and n-3 PUFAs specifically in the context of HIV and pregnancy. Our objective was to assess HIV clinical factors associated with PUFA signatures in pregnant persons with HIV (PWH). In this observational cohort, third trimester plasma PUFA concentrations (six n-6 PUFAs, four n-3 PUFAs) were measured, each as a percent of total fatty acid content, via esterification and gas chromatography in pregnant PWH enrolled from 2009 to 2011 in the Nutrition substudy of the Pediatric HIV/AIDS Cohort Study. PUFA ratios (n-6:n-3) were calculated. Exposures assessed were first/second trimester CD4 count (<200 vs. >200 cells/mm3), HIV RNA viral load (VL) (VL >400 vs. <400 copies/mL), and protease inhibitor (PI) versus non-PI antiretroviral therapy (ART). Linear regression models using generalized estimating equations were fit to assess mean differences and their 95% confidence intervals (CIs) in n-6:n-3 by each exposure, adjusted for potential confounders. Of 264 eligible pregnant PWH, the median age was 27 years, 12% had CD4 counts <200 cells/mm3, and 56% had VL ≥400 copies/mL in the first/second trimesters. PUFA concentrations and ratios were similar by CD4 count and PI exposure. n-3 concentrations were lower in PWH with VL ≥400 versus <400 copies/mL (median 2.8% vs. 3.0%, p < .01, respectively); no differences were observed for n-6 concentrations by VL. In models adjusted for age, education, tobacco use, body mass index, and PI-based ART, n-6:n-3 was higher in those with VL ≥400 copies/mL (mean difference: 1.6; 95% CI: 0.79-2.48, p = .0001). Therefore, PUFA signatures in viremic pregnant PWH reflect a proinflammatory eicosanoid milieu. Future studies should evaluate associations of proinflammatory PUFA signatures with adverse perinatal outcomes in PWH.