Drug interactions
Remdesivir has not been evaluated for drug-drug interactions in humans. The clinical relevance of in vitro drug interactions also has not been established. According to the FDA, remdesivir is a substrate for the drug metabolizing enzymes CYP2C8, CYP2D6, and CYP3A4, and is a substrate for organic anion transporting polypeptides 1B1 (OAPT1B1) and P-glycoprotein (P-gp) transporters. In vitro, remdesivir inhibits CYP3A4, OATP1B1, OATP1B3, BSEP, MRP4, and NTCP.1
Pregnancy risk summary
Remdesivir has not been studied adequately in pregnant women and only should be used during pregnancy if the potential benefit of the drug justifies the potential risk to both mother and fetus.
Nonclinical animal studies that included systemic exposure of the predominant circulating metabolite of remdesivir in pregnant rats and rabbits (at 4 times the recommended dose of human exposure) demonstrated no adverse effect on embryofetal development.1
Breastfeeding
The only information regarding breastfeeding and remdesivir comes from animal studies. The drug and its metabolites were detected in the plasma of nursing rat pups whose mothers given intravenous remdesivir daily from gestation day 6 to lactation day 20. Measured on lactation day 10, remdesivir exposure in the pups was about 1% that of maternal exposure.1
“Because of the potential for viral transmission to SARS-CoV-2-negative infants and adverse reactions from the drug in breastfeeding infants, the developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for remdesivir and any potential adverse effects on the breastfed child from remdesivir or from the underlying maternal condition.”1