Markers of Maternal Bone and Renal Toxicity Through 50 Weeks Postpartum: IMPAACT 2010 (VESTED) Trial

Safety data from randomized trials of antiretrovirals in pregnancy are scarce. We evaluated maternal bone and renal data from the International Maternal Pediatric Adolescent AIDS Clinical Trials Network 2010 trial, which compared the safety and efficacy of 3 antiretroviral therapy regimens started in pregnancy: dolutegravir + emtricitabine/tenofovir alafenamide (DTG + FTC/TAF), dolutegravir + emtricitabine/tenofovir disoproxil fumarate (DTG + FTC/TDF), and efavirenz/emtricitabine/tenofovir disoproxil fumarate (EFV/FTC/TDF).

A subset of participants underwent dual-energy X-ray absorptiometry scans at postpartum week 50 only. Maternal bone mineral density (BMD) Z-scores were compared between arms. Maternal creatinine was measured at enrolment and periodically through week 50 postpartum, and by-arm differences in average weekly change in estimated creatinine clearance were compared.

Six hundred forty-three participants were randomized to DTG + FTC/TAF (N = 217) or DTG + FTC/TDF (N = 215) or EFV/FTC/TDF (N = 211). Median age = 27 years (IQR 23, 32), median CD4 count = 466 cells/mm3 (IQR 308, 624); 564 (88%) women enrolled in Africa and 479 (74%) breastfed. Week 50 postpartum dual-energy X-ray absorptiometry results from 154 women were included in the analysis. Hip and spine BMD was on average higher in women in the DTG + FTC/TAF and lower in the DTG + FTC/TDF and EFV/FTC/TDF arms, but no significant differences in BMD Z-scores were observed between treatment groups. The weekly rate of change in estimated creatinine clearance differed among treatment groups during the antepartum period, but not over the full study follow-up.

Markers of bone and renal toxicity did not differ significantly through week 50 postpartum among women randomized to start DTG + FTC/TAF or DTG + FTC/TDF or EFV/FTC/TDF in pregnancy.