Pregnancy Outcomes in Pregnant Women with HIV on Tenofovir Disoproxil Fumarate (TDF) Compared to Tenofovir Alafenamide (TAF)

OBJECTIVE: Our objective was to assess the safety, efficacy, and pregnancy outcomes of Tenofovir Disoproxil Fumarate (TDF) compared to Tenofovir Alafenamide (TAF) use in pregnant women with HIV (PWLHIV). METHODS: This retrospective cohort study of all women who received prenatal care at a single academic center between January 1(st) 2015 and June 30(th), 2020 compared outcomes in PWLHIV using TDF compared to TAF. The primary outcome was weight-gain during pregnancy. Secondary outcomes included CD4 count, viral-load, gestational age at delivery, fetal and neonatal outcomes. Outcomes were analyzed using standard statistical tests. Multivariable linear-regression analysis models accounting for potential confounders were created for primary and secondary outcomes, with beta coefficients (β) and associated 95% confidence intervals as the primary measure of effect. Statistical analysis was done with STATA 16. RESULTS: There were 66 women in the TDF group and 34 women in the TAF group. In the overall cohort, the median (interquartile range, IQR) gestational age at delivery for PWLHIV on TDF and TAF were 38.6 (IQR 37.5–39.4) and 38.1 (31.1–39.1) weeks respectively; and most women (85%) were Black/African American. Compared to PWLHIV on a TDF regimen, women on TAF, on average, gained over 3 kg more weight in the 3(rd) trimester of pregnancy (β=3.20, 95% CI 1.64, 7.97; p=0.03). Women in the TAF arm were also more likely to have higher median CD4-count (470 cells/mm(3) versus 669 cells/mm(3), p=0.035) in the third trimester compared to women on TDF. There were no cases of neonatal/infant HIV or death. CONCLUSION: Although TAF use was associated with more weight gain compared to TDF, both regimens appear safe and effective during pregnancy. PWLHIV should be counseled about the potential for weight gain with TAF based regimens during pregnancy.