Table 5.

Pharmacokinetic Parameters Following a Single Infusion of 10 mg/kg Bezlotoxumab in Two Age Cohorts of Pediatric Participants Versus Adult Participants in Prior Studies

	Pediatric Participants			Adult Participants			Pediatric/ Adult Participants
Parameter	N	GM	95% CI	N	GM	95% CI	GMR	90% CI	rMSEa
Age cohort 1: 12 to <18 years
AUC0-inf (h * μg/mL)	36	56 100	(49400, 63700)	1550	52 800	(51800, 53800)	1.06	(0.95, 1.18)	0.388
Cmax (μg/mL)	37	155	(145, 166)	1550	184	(183, 186)	0.84	(0.79, 0.89)	0.217
Tmax (h)b	37	3.00	(2.67, 3.47)	1550	1.00	(0.0667, 4.73)
t1/2 (day)c	36	21.7	22.1	1550	18.7	27.7
Vd (L)c	36	7.50	33.3	1550	7.34	16.3
CL (mL/h)c	36	9.99	33.7	1550	13.2	40.4
Weight-normalized Vd (L/kg)c	36	0.134	29.9
Weight-normalized CL (mL/h/kg)c	36	0.178	31.0
Age cohort 2: 1 to <12 years
AUC0-inf (h * μg/mL)	54	43 200	(38900, 47900)	1550	52800	(51800, 53800)	0.82	(0.75, 0.89)	0.388
Cmax (ug/mL)	54	129	(122, 137)	1550	184	(182, 187)	0.70	(0.67, 0.74)	0.220
Tmax (h)b	54	3.00	(2.67, 285)	1550	1.00	(0.0667, 4.73)
t1/2 (day)c	54	18.1	33.8	1550	18.7	27.7
Vd (L)c	54	2.93	54.6	1550	7.34	16.3
CL (mL/h)c	54	4.66	59.6	1550	13.2	40.4
Weight-normalized Vd (L/kg)c	54	0.146	28.9
Weight-normalized CL (mL/h/kg)c	54	0.233	34.5

Abbreviations: AUC_0-inf, area under the curve from time zero to infinity; BLOQ, below assay limit of quantitation; CI, confidence interval; CL, clearance; C_max, maximum serum concentration; GM, geometric least-squares mean; t_½ = terminal half-life; T_max = time of peak serum concentration; V_d = volume of distribution.

^arMSE: square root of conditional mean squared error (residual error) from the linear fixed-effect model. rMSE * 100% approximates the between-subject percent CV on the raw scale.

^bMedian (min, max) reported for T_max.

^cGeometric mean, percent CV reported for apparent terminal t_½, V_d, and CL.