Table 1.

Baseline characteristics of healthy Chinese adults aged 18 to 59 years participated in the phase 1 and phase 2 trials.

	Phase 1 trial (0/14)			Phase 2 trial (0/14)			Phase 2 trial (0/28)
Items	5 μg group (N = 24)	10 μg group (N = 24)	Placebo group (N = 12)	5 μg group (N = 100)	10 μg group (N = 100)	Placebo group (N = 50)	5 μg group (N = 100)	10 μg group (N = 100)	Placebo group (N = 50)
Age (years), mean (SD)	38.0 (9.5)	41.0 (10.3)	38.3 (8.8)	45.5 (9.3)	44.9 (9.5)	46.2 (9.2)	42.4 (10.5)	44.5 (10.7)	41.7 (10.0)
Sex, n (%)
Male	12 (50)	10 (42)	8 (8/12)	53 (53)	45 (45)	19 (38)	38 (38)	46 (46)	25 (50)
Female	12 (50)	14 (58)	4 (4/12)	47 (47)	55 (55)	31 (62)	62 (62)	54 (54)	25 (50)
Completed, n (%)	23 (96)	24 (100)	12 (12/12)	100 (100)	97 (97)	48 (96)	98 (98)	99 (99)	49 (98)
Discontinued, n (%)	1 (4)	0	0	0	3 (3)	2 (4)	2 (2)	1 (1)	1 (2)
Neutralising antibody to live SARS-CoV-2
Seropositive	0	0	0	0	0	0	0	0	0
GMT	2 (2–2)	2 (2–2)	2 (2–2)	2 (2–2)	2 (2–2)	2 (2–2)	2 (2–2)	2 (2–2)	2 (2–2)
Neutralising antibody to pseudovirus
Seropositive	0	0	0	6 (6, 2–13)	1 (1, 0–5)	0	2 (2, 0–7)	2 (2, 0–7)	2 (4, 0–14)
GMT	8 (6–10)	10 (8–12)	7 (5–9)	8 (7–9)	8 (7–9)	7 (6–8)	11 (9–12)	9 (8–10)	9 (8–10)
RBD-IgG
Seropositive	0	0	0	0	0	0	0	0	1 (2, 0–11)
GMT	10 (10–10)	10 (10–10)	10 (10–10)	11 (10–13)	11 (10–12)	10 (10–10)	10 (10–12)	10 (10–11)	10 (10–11)

Data are presented as n (95% CI [%]) for GMT, number of participants (%, 95% CI [%]) for seropositive (antibody titer ≥ detection limit). 0/14 or 0/28: Participants received two doses on Days 0 and 14 or Days 0 and 28, respectively; CI: Confidence interval. GMT: Geometric mean titer; N: Number of participants randomized into each treatment group; RBD-IgG: Antibody directed against the receptor-binding domain; SARS-CoV-2: Severe acute respiratory syndrome coronavirus 2; SD: Standard deviation.