Statistical design of Phase II/III clinical trials for testing therapeutic interventions in COVID-19 patients

Table 9 Required Sample Size for High-Risk Group Patients with One Interim Analysis

Required Sample Size for High-Risk Group Patients with One Interim Analysis
	Power = 80%						Power = 90%
	P0 = 80%			P0 = 70%			P0 = 80%			P0 = 70%
P1	N1	N2	Total	N1	N2	Total	N1	N2	Total	N1	N2	Total
70%	170	340	510	NA	NA	NA	235	470	705	NA	NA	NA
65%	78	156	234	827	1654	2481	108	216	324	1144	2288	3432
60%	45	90	135	211	422	633	62	124	186	292	584	876
55%	29	58	87	95	190	285	41	82	123	132	264	396
50%	21	42	63	54	108	162	28	56	84	74	148	222
45%	15	30	45	35	70	105	21	42	63	48	96	144
40%	12	24	36	24	48	72	16	32	48	33	66	99
35%	NA	NA	NA	17	34	51	NA	NA	NA	24	48	72

P0: 30 days mortality rate in the standard arm. P1: 30 days mortality rate in the treatment arm
N1: sample size for the standard care arm. N2: sample size for the treatment arm
For 80% power: probability of rejection at each look: 1^st look p < 0.006, futility look p > 0.709, final look p < 0.047
For 90% power: probability of rejection at each look: 1^st look p < 0.006, futility look p > 0.716, final look p < 0.047
1:2 randomization; p = 2

ISSN: 1471-2288