Table 3.

Observed Peak and Trough Concentrations of f-ara-ATP with Each Dose of Fludarabine

Sample Collection Time	Concentration of f-ara-ATP*
	Dose 1	Dose 2	Dose 3	Dose 4	Dose 5	P Value†
2 Hr after start of infusion	7.9 (.7-18)	1.5 (.5-19.8)	3.4 (.4-12)	1.7 (.2-7)	.6 (.2-1.4)	<.001
No. of samples	27	4	22	28	5
24 Hr after start of infusion	2.0 (0-6.9)	.5 (.1-7.3)	1.0 (.3-8.3)	.9 (.1-10.3)	.5 (.1-7.2)	.57
No. of samples	33	12	25	31	6

^*Data are presented as median (range) and expressed as pmoles/million clls.

^†The P value is based on a simple linear regression using dosing event as predictors on f-ara-ATP concentrations.