CROI 2015 Program and Abstracts

Abstract Listing

Poster Abstracts

Results: The overall incidence of PT was 56/7937 (0.7%). No case of transmission occurred among the 2588 women who were on HAART before conception, without treatment interruption during the first trimester, and who delivered with a plasma VL <50 copies /mL (upper 95% confidence interval limit: 0.1%). VL and timing of HAART initiation were independently associated with PT in logistic regression (Fig 1). Regardless of viral load, the transmission rate increased from 0.2% for women initiating HAART prior to conception to 0.4% during the 1 st trimester, 0.9% during the 2 nd trimester and 2.2% during the 3 rd trimester; p<0.001. Regardless of timing of HAART initiation, the rate was higher for women with VL between 50 and 400 copies/mL near delivery than for those with < 50 copies/mL: adjusted odds ratio = 3.5 [95%CI: 1.7 -7.3].

Conclusions: Perinatal HIV-1 transmission is virtually zero in mothers who start antiretroviral therapy before conception and maintain suppression of the plasma viral load. 868 Predictors of Perinatal HIV Transmission in the BAN Study Sascha R. Ellington 1 ; Athena P. Kourtis 1 ; Ali Fokar 2 ; Charles S. Chasela 4 ; Dumbani Kayira 3 ; GeraldTegha 3 ; Denise J. Jamieson 1 ; Charles M. van der Horst 2 The BAN StudyTeam 1 US Centers for Disease Control and Prevention (CDC), Atlanta, GA, US; 2 University of North Carolina, Chapel Hill, NC, US; 3 University of North Carolina Project Lilongwe, Lilongwe, Malawi; 4 University of Witwatersrand, Johannesburg, South Africa Background: Mother-to-child transmission of HIV (MTCT) can occur in utero, at the time of delivery, or postnatally through breastfeeding. In breastfeeding populations and in the absence of antiretroviral (ARV) prophylaxis, up to 70% of MTCT occurs in utero or intrapartum. Methods: We conducted a case cohort study to assess predictors of perinatal (in utero or intrapartum) MTCT using data from the Breastfeeding, Antiretrovirals and Nutrition (BAN) study. All mothers in labor and their infants received single-dose nevirapine and zidovudine/lamivudine for 7 days. The BAN study randomized ARV-naïve women with CD4 count>200/250 to maternal ARV, infant nevirapine or control to examine the role of ARV on postnatal MTCT. Cases were 119 mothers that transmitted HIV to their infants by 2 weeks postpartum; controls were mothers whose infants were uninfected by 4 weeks of age (N=2120). Laboratory, clinical and demographic maternal characteristics were evaluated as predictors of perinatal MTCT in bivariate analyses and, for those variables significant in bivariate analyses when stratified or adjusted by HIV viral load (p<0.1), multivariable logistic regression. Results: Among 119 perinatally infected infants, 115 were positive at birth and 4 were negative at birth but positive by 2 weeks of life. Transmitting mothers had significantly higher median HIV viral load during pregnancy compared to non-transmitting mothers (64,263 vs 16,393 copies/ml, p<0.001). There was one perinatal transmission in a mother with viral load <1,000 copies. Anemia was a strong predictor of perinatal MTCT in mothers with a viral load ≤ 10,000 copies/ml (OR 5.0, 95%CI 1.1-23.9), but not among mothers with higher viral load. After adjusting for viral load and covariates, mothers currently facing a food shortage had a 60% increased odds of perinatal MTCT (p=.01), as did those with a history of herpes zoster (OR 3.3, 95%CI 1.8-5.9), and those reporting an STI in the last 12 months (88% increased odds of perinatally transmitting HIV, p=.05).

Poster Abstracts

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CROI 2015