In this study, we will examine whether the KRG extract administration can significantly reduce the frequency, severity, and duration of ILI symptoms. A 1000-mg dose of KRG will be taken 3 times daily by subjects for 12 weeks. Initial ILI symptoms will be confirmed by the collaborating physician at the screening visit of self-reported ILI symptoms, and relief of symptoms will be confirmed within 7 day of the subject's self-reported recovery. Subjects will be recorded daily symptom severity in a journal using a 4-point severity score.
The aim of this study is to evaluate the efficacy of the KRG extract on the frequency, severity, and duration of ILI symptoms. For this purpose, the ability of the KRG extract to reduce the ILI incidence will be assessed in 100 healthy volunteers.
In this study, we expect that the KRG extract can effectively reduce the ILI incidence. Some studies have assessed the relative potency of ginseng extracts by evaluating their ability to prevent the upper respiratory tract infections. The ginseng extracts has been studied in 3 recent RCTs to prevent the common cold, the flu, or upper respiratory infections. Two studies did not show differences between the ginseng extract and placebo in terms of decreasing duration, severity, or frequency of overall symptoms [25, 26]. One study demonstrated that the ginseng extracts decreased duration, severity, and frequency of symptoms .
To the best of our knowledge, there has been no report demonstrating the preventive efficacy of KRG extract on ILI incidence. Therefore, if this study will be successfully performed, the KRG extract may offer beneficial effects in reducing ILI incidence. And these results will be applied to children and elderly populations. To draw confirmative conclusion about the preventive efficacy and safety of the KRG extract on ILI incidence, a full-scale RCT is being conducted now. If there are any conclusions in the near future, we would like to publish them later.