Table 2.

Busulfan clearance in subjects ≥ 60 years old (100103) and patients <60 years old (19808 and 10503).

CALGB Study	19808	10503	19808+10503	100103
Median age (range)	50.3(19.3–59.6)	49.6(17.8–60.0)	49.8 (17.8–60.0)	66.3 (60.3–74.3)
CL (mL/min)
Mean	180	190	186	263
Median	172	163	168	236
Range	40–580	28–560	28–580	72–588
P-value*				0.0002
CL/ABW (mL/min/kg)
Mean	2.34	2.34	2.34	3.22
Median	2.3	2.1	2.1	3.0
Range	0.5–4.8	0.2–5.8	0.2–5.8	1.2–6.5
P-value*				0.0001
CL/IBW (mL/min/kg)
Mean	2.91	2.90	2.91	3.63
Median	2.6	2.6	2.6	3.8
Range	0.6–10.4	0.4–8.1	0.4–10.4	1.2–7
P-value*				0.0035
CL/CBW (mL/min/kg)
Mean	2.7	2.7	2.7	3.5
Median	2.6	2.5	2.6	3.4
Range	0.6–8.1		0.3–8.1	1.2–6.7
P-value*				0.0005
t½ (h)
Mean	3.88	3.93	3.91	3.70
Median	3.00	2.77	2.82	2.62
Range	1.05–29.4	0.28–33.0	0.28–33.0	1.24–12.4
P-value*				0.74
Vd (L)
Mean	49.4	50.9	50.4	77.6
Median	44.5	41.6	43.4	59.2
Range	20.5–125	7.3–302	7.3–302	15.5–228
P-value*				0.0023

^*patients <60 years old and ≥60 years old i.e CALGB100103 vs CALGB 19808 + CALGB 10503.

ABW, actual bodyweight; IBW, ideal bodyweight, CBW, corrected bodyweight (used to dose)