RESUMEN
Atazanavir-ritonavir concentrations change over time during pregnancy in HIV-positive patients; the impact of genetic variants is unknown. Twenty patients were enrolled in this study; plasma and intracellular concentrations of antiretrovirals were measured, in addition to single-nucleotide polymorphisms in transport-related genes. Linear logistic regression showed that genetic variants in organic-anion-transporter-1B1- and pregnane-X-receptor-encoding genes affected third-trimester atazanavir exposure. In this prospective study, genetic variants partially explained the observed interpatient variability in third-trimester exposure to antiretrovirals.
Asunto(s)
Sulfato de Atazanavir/farmacocinética , Sulfato de Atazanavir/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/uso terapéutico , Transportador 1 de Anión Orgánico Específico del Hígado/genética , Receptor X de Pregnano/genética , Ritonavir/farmacocinética , Ritonavir/uso terapéutico , Adulto , Sulfato de Atazanavir/sangre , Esquema de Medicación , Quimioterapia Combinada , Femenino , Inhibidores de la Proteasa del VIH/sangre , Inhibidores de la Proteasa del VIH/farmacocinética , Humanos , Polimorfismo de Nucleótido Simple/genética , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Tercer Trimestre del Embarazo , Estudios Prospectivos , Ritonavir/sangreRESUMEN
BACKGROUND: Atazanavir (300 mg) boosted by ritonavir (100 mg) is the preferred third drug in pregnancy. However, there is still discordance on atazanavir dose increase during the third trimester. OBJECTIVES: To evaluate plasma and intracellular atazanavir and ritonavir concentrations in HIV-infected women during pregnancy and after delivery. METHODS: This was an observational study. HIV-infected pregnant patients treated with atazanavir/ritonavir plus either tenofovir/emtricitabine or abacavir/lamivudine had been prospectively enrolled after having signed a written informed consent form. Plasma and intracellular atazanavir and ritonavir Ctrough (24â±â3 h after drug intake) were measured at each visit during the first, second and third trimesters and post-partum using validated HPLC-MS and HPLC-photodiode array methods (with direct evaluation of cellular volume). Data are described as median (IQR) and compared through non-parametric tests. RESULTS: Twenty-five patients were enrolled; at baseline, the median age was 32 years (27-35). All patients had plasma HIV RNA <50 copies/mL; the median CD4+ count was 736 cells/mm3 (542-779). Atazanavir plasma concentrations were 441 ng/mL (261-1557), 710 ng/mL (338-1085), 556 ng/mL (334-1022) and 837 ng/mL (608-1757) during the first, second and third trimesters and post-partum, respectively; intracellular concentrations were 743 ng/mL (610-1928), 808 ng/mL (569-1620), 756 ng/mL (384-1074) and 706 ng/mL (467-2688), respectively. Atazanavir intracellular/plasma ratios were 1.32 (0.98-2.77), 1.34 (1.13-1.88), 1.38 (0.61-2.63) and 1.07 (0.56-2.69), respectively. Atazanavir intracellular concentrations and intracellular/plasma ratios showed non-significant changes over time (P > 0.05). CONCLUSIONS: This is the first demonstration that intracellular atazanavir exposure remains unchanged during pregnancy supporting the standard 300/100 mg atazanavir/ritonavir dosing throughout pregnancy.
