Efficacy and Safety of CVT-E002, a Proprietary Extract of Panax quinquefolius in the Prevention of Respiratory Infections in Influenza-Vaccinated Community-Dwelling Adults: A Multicenter, Randomized, Double-Blind, and Placebo-Controlled Trial

Table 2

Overall between-group comparison of infection rates, and severity and duration of URIs.

	Treatment groups			𝑃 value
	Placebo	CVT-E002-400 mg	CVT-E002-800 mg
ITT (intention to treat)
𝑛	253	249	246
Lab-confirmed clinical URIs	14 (5.5%)	13 (5.2%)	11 (4.5%)	0.89^a
Jackson-confirmed URIs	67 (26.5%)	54 (21.7%)	47 (19.1%)	0.23^a
Subjects completing the study
𝑛	197	210	196
Lab-confirmed clinical URIs	12 (6.1%)	9 (4.3%)	9 (4.6%)	0.67^b
Number of infections/subject	0.06 (0.24)	0.05 (0.26)	0.046 (0.21)	0.68^c
Total days of infection	1.14 (5.3)	0.88 (4.6)	0.69 (4.2)	0.67^c
Total symptom score	3.86 (17.7)	5.1 (29.1)	2.85 (15.1)	0.82^c
Jackson-confirmed URIs	57 (28.9%)	42 (20.0%)	38 (19.4%)	0.04^b
Number of URIs/subject	0.36 (0.64)	[209] 0.23 (0.50)	0.24 (0.56)	0.04^c
Total days of URI	4.87 (11.2)	3.13 (7.9)	2.93 (7.2)	0.05^c
Total symptom score	23.0 (49.6)	[209] 17.0 (43.3)	15.3 (38.0)	0.05^c

^aBetween group comparisons made using log-rank test.
^bBetween-group comparisons made using chi-square test for comparing proportions.
^cBetween-group comparisons made using Wilcoxon two-sample test.
Jackson-confirmed URIs (subset analysis):
 Total number: Placebo versus 400 mg, 𝑃<0.04; versus 800 mg, 𝑃<0.03; 400 mg versus 800 mg, 𝑃<0.88.
 Number of URIs/subject: placebo versus 400 mg, 𝑃<0.04; versus 800 mg, 𝑃<0.03; 400 mg versus 800 mg, 𝑃<0.92.
 Total days of URI: placebo versus 400 mg, 𝑃<0.06; versus 800 mg, 𝑃<0.05; 400 mg versus 800 mg, 𝑃<0.89.
 TSS: placebo versus 400 mg, 𝑃<0.05; versus 800 mg, 𝑃<0.04; 400 mg versus 800 mg, 𝑃<0.92.