Use of Tenofovir Diphosphate Levels to Predict Viremia During the Postpartum Period in Women Living With Human Immunodeficiency Virus (HIV): A Nested Case-Control Study . (3rd January 2022)

• Record Type: Journal Article
• Authors: Odayar, Jasantha; Orrell, Catherine; Phillips, Tamsin K; Hu, Nai Chung; Kabanda, Siti; Malaba, Thokozile R; Allerton, Joanna; Wiesner, Lubbe; Hsiao, Nei yuan; Castillo-Mancilla, Jose; Lesosky, Maia; Myer, Landon
• Is Part Of: Clinical infectious diseases. Volume 75:Number 5(2022)
• Page Start: 761
• Page End: 767
• Publication Date: 2022-01-03
• Subjects: antiretroviral therapy -- adherence -- dried blood spots -- tenofovir diphosphate -- predictive value; Communicable diseases -- Periodicals; 616.905
• DOI: 10.1093/cid/ciab1068
• Languages: English
• ISSNs: 1058-4838

Abstract

Abstract: Background: There are few data on the utility of tenofovir diphosphate (TFV-DP) in dried blood spots (DBSs) to predict future viral load (VL) in postpartum women with HIV on antiretroviral therapy (ART). Methods: We conducted a nested case-control study within a trial of postpartum ART delivery strategies. Participants started ART containing tenofovir disoproxil fumarate (TDF) in pregnancy, were <10 weeks postpartum, and had a VL <400 copies/mL. VL and TFV-DP samples were taken every 3–6 months over 24 months. Cases had ≥1 VL ≥20 copies/mL; controls were randomly sampled from women with persistent viral suppression (VS; VL <20 copies/mL). Generalized estimating equations were used to calculate likelihood odds ratios (LORs) for future VL ≥20 copies/mL by TFV-DP concentration at the preceding visit. Results: 61 cases and 20 controls contributed 365 DBS-VL pairs (median ART duration, 16 months). Sensitivity and specificity of TFV-DP <700 fmol/punch to detect future viremia were 62.9% (95% CI, 54.7–70.6%) and 89.7% (84.9–93.4%), respectively. Adjusting for age, ART duration, previous VL, and duration between the TFV-DP and VL measures, LORs of viremia for TFV-DP concentrations 350–699 and <350 fmol/punch versus TFV-DP ≥1850 fmol/punch were 3.5 (95% CI, 1.1–10.8; P = .033) and 12.9 (3.6–46.6; P < .0001), respectively. Including only samples taken during VS, the LOR of future viremia for TFV-DP concentration <350 fmol/punch versus TFV-DP ≥1850 fmol/punch was 9.5 (1.9–47.0). Conclusions: TFV-DP concentrations in DBSs were strongly associated with future viremia and appear useful to identify nonadherence and predict future elevated VL. Abstract : Among South African women with HIV using tenofovir-containing antiretroviral therapy, tenofovir diphosphate concentrations were strongly associated with subsequent viremia occurring up to 6 months later, supporting use of this biomarker to identify nonadherence, predict potential viremia, and inform clinical management.