CROI 2016 Abstract eBook

Abstract Listing

Oral Abstracts

36

Impact of Maternal Tenofovir Use on HIV-Exposed Newborn Bone Mineral George K. Siberry 1 ; CamlinTierney 2 ; Lynda Stranix-Chibanda 3 ; Caroline Marr 2 ; John A. Shepherd 4 ; Renee Browning 5 ; Heidi J. Kalkwarf 6 ; Kathleen George 7 ; Mary G. Fowler 8 ; for the IMPAACT P1084s StudyTeam 1 Eunice Kennedy Shriver NICHD, Bethesda, MD, USA; 2 Harvard Sch of PH, Boston, MA, USA; 3 Univ of Zimbabwe, Harare, Zimbabwe; 4 Univ of California San Francisco, San Francisco, CA, USA; 5 NIAID, NIH, Rockville, MD, USA; 6 Cincinnati Children’s Hosp Med Cntr, Cincinnati, OH, USA; 7 IMPAACT Operations, Durham, NC, USA; 8 Johns Hopkins Univ Sch of Med, Baltimore, MD, USA Background: A US cohort study (CID 2015;61:996) reported 12% lower newborn mean bone mineral content (BMC) after maternal tenofovir disoproxil fumarate (TDF) use. Methods: The P1084s substudy sought to compare newborn BMC by exposure to maternal antiretroviral (ARV) regimens at >14 weeks gestational age (GA) randomly assigned in the IMPAACT PROMISE trial: Arm 1: zidovudine[ZDV] (+ single-dose nevirapine+ TDF/emtricitabine[FTC] tail); Arm 2: ZDV/lamivudine/lopinavir-ritonavir[LPVr]; Arm 3: TDF/ FTC/LPVr. Infants underwent whole-body (WB) and lumbar spine (LS) dual-energy X-ray absorptiometry (DXA) BMC measurements by age 28 days at 8 African sites equipped and trained for infant DXA scans. Standardized scan analysis was performed centrally. The accrual target of 150 infants per Armwas based on 80% power to detect a pair-wise difference of 4-5% in mean WB-BMC and 6-7% in mean LS-BMC. Maternal and infant characteristics were compared with Fisher’s exact, Chi-square or Kruskal-Wallis tests, as appropriate. Mean BMC differences were compared with Student’s t-test. Because mothers enrolled in the substudy after randomization, we used multivariable linear regression to adjust for baseline maternal factors and infant factors at time of DXA scan. Results: Of 452 eligible mothers, data from 425 infants remained for analysis after accounting for twins(6), fetal (8) or neonatal death(10) and drop-outs(15). Mothers differed across Arms on age (median 25 vs 27 vs 27 years, p=.008). Newborns differed in birth weight (median 3090 vs 2900 vs 2900g, p<.001) and weight-for-length Z-score (mean -0.4 vs -0.8 vs -0.8, p=.032) but not GA (median 39 weeks for all Arms, p=.264) or birth length (median 49cm for all Arms, p=.327). By Arm, mean LS-BMC were 1.73 vs. 1.64 vs 1.72g and WB-BMC were 73.1 vs. 65.1 vs. 63.3g. Pairwise comparisons revealed no significant differences between Arms 2 and 3 (primary objective) for LS- and WB-BMC but significantly lower mean WB-BMC in Arms 2 and 3 compared to Arm 1, which persisted after adjustment (Table). Differences of borderline significance emerged in some pairwise comparisons of LS-BMC when adjusted for maternal or maternal and infant factors. Conclusions: No adverse infant BMC effect was linked to maternal TDF use. Initiation of a triple-ARV, LPVr-containing regimen during pregnancy may lead to lower newborn bone mineralization.

Oral Abstracts

13

CROI 2016