In vivo inhibition of erythrocyte thymidine transport in a rhesus monkey following intravenous infusion of NBMPR-P. This graph shows the percentage of inhibition of tritiated thymidine transport in peripheral blood erythrocytes after treatment with either with 1 mg/kg (▧) or 3 mg/kg (▪) of NBMPR-P. As a reference point to define 100% transport function, baseline levels were determined immediately before drug infusion (0 hours). The relative levels of inhibition are shown at various time points, including 24 hours after infusion.