Clinical trial simulation to evaluate power to compare the antiviral effectiveness of two hepatitis C protease inhibitors using nonlinear mixed effect models: a viral kinetic approach

Table 3 Power (%) to detect a difference of effectiveness between PI-A and PI-B according to the study design and the effectiveness of PI-B ( ϵ ^B ), assuming ϵ ^A = 0.999 and a limit of detection (“ML data”)

	ϵ ^B	0.998	0.995	0.990	0.998	0.995	0.990	0.998	0.995	0.990
Small sample size	Design*	N = 10 and n = 7			N = 14 and n = 5			N = 10 and n = 5
	Design*	n_tot = 70			n_tot = 70			n_tot =50
	Wald test (uncorrected)	62.2	99.8	100	61.8	100	100	55.2	98.8	100
	Wald test (corrected)	44.2	98.4	100	50.4	100	100	35.8	95.8	100
	Wilcoxon test	6.6	11.2	26.8	4.4	15.6	39.0	6.6	11.2	26.8
	Design*	N = 20 and n = 7			N = 28 and n = 5			N = 20 and n = 5
	Design*	n_tot = 140			n_tot = 140			n_tot = 100
Middle sample size	Wald test (uncorrected)	83.4	100	100	86.8	100	100	77.8	100	100
	Wald test (corrected)	69.0	100	100	78.0	100	100	58.8	100	100
	Wilcoxon test	7.0	23.0	50.4	6.8	30.4	64.6	7.0	23.0	50.4
Large sample size	Design*	N = 30 and n = 7			N = 42 and n = 5			N = 30 and n = 5
	Design*	n_tot = 210			n_tot = 210			n_tot = 150
	Wald test (uncorrected)	94.0	100	100	86.8	100	100	89.4	100	100
	Wald test (corrected)	89.2	100	100	82.6	100	100	82.6	100	100
	Wilcoxon test	7.4	31.0	67.0	9.2	43.8	85.0	7.4	31.0	67.0

* N: number of patients per group of treatment; n: number of viral load measurements per patient; n_tot: total numbers of observations per group of treatment.

ISSN: 1471-2288