Clofarabine triphosphate pharmacokinetics in responders and nonresponders. The analog triphosphate levels were compared at the end of infusion (eoi) on day 1 (d1-eoi) and day 2 (d2-eoi) in patients who were responders (A) or nonresponders (B). Each bar represents an individual patient. The increase in clofarabine triphosphate value was determined in these patients after calculating and plotting the ratio of clofarabine triphosphate on day 2 versus day 1 (C). Horizontal bars represent median values.