Concentrations of tenofovir and emtricitabine in breast milk of HIV-1-infected women in Abidjan, Cote d'Ivoire, in the ANRS 12109 TEmAA Study, Step 2

Abstract

The aim was to evaluate emtricitabine (FTC) and tenofovir (TFV) neonatal ingestion through breast milk. Median TFV and FTC breast milk doses represented 0.03% and 2%, respectively, of the proposed oral infant doses. Neonatal simulated plasma concentrations were extremely low for TFV but between the half-maximal inhibitory concentration and the adult minimal expected concentration for FTC. The rare children who will acquire HIV despite TDF-FTC therapy will need to be monitored for viral resistance acquisition.

FIG. 1.

Neonatal tenofovir (TFV) (left panel) and emtricitabine (FTC) (right panel) concentrations during the first week of life, from placental transfer only (dotted curve) and from both placental transfer and breast-feeding (solid curves). Data are from the ANRS 12109 TEmAA study (Step 2), Abidjan, Côte d'Ivoire, 2009. Note that, up to approximately 110 h, concentrations resulted from placental transfer and breast-feeding; thereafter, neonatal concentrations resulted only from breast-feeding (every 4 h). The arrow links the concentrations with the median, minimal, and maximal breast-feeding doses. The lower horizontal dashed line corresponds to the IC₅₀ (0.01 mg/liter for TFV and 0.002 mg/liter for FTC), and the upper horizontal dashed line corresponds to the minimal expected trough concentrations in adults (0.056 mg/liter for TFV and 0.077 mg/liter for FTC).