Background: In this study, we investigated the therapeutic potential effects of G1899 Korean Red Ginseng Extract Powder(G1899) on long COVID in a general population using flow cytometry and follow-up by questionnaire.
Methods: We conducted a 12-week clinical pilot study on 220 COVID19 patients who were recently infected. The study was completed by 108 participants in the G1899 group and 108 participants in the placebo group. Participants were randomized 1:1 to the G1899 and placebo groups. We evaluated the long COVID by questionnaire including GAD-7, FSS and BFI-K at baseline and 12 weeks. To investigate the changes in the levels of CD4/CD8 T cell ratio and regulatory T cell population, multicolor flow cytometry was performed.
Results: The G1899 group showed significantly chronic fatigue symptoms relieving compared with placebo group at 12 weeks in women. The CD4/CD8 ratio increased significantly in the G1899 group, rising from 1.71 (95 % CI: 1.35-2.07) at Visit 1 to 2.31 (95 % CI: 1.83-2.78) at Visit 4 (p = 0.0029). Unlike the G1899 group, there was a significant reduction in the Treg population, from 2.02 % at Visit 1-1.22 % at Visit 4 (p = 0.0005) in the placebo group.
Conclusion: These findings suggest that G1899 has beneficial effects on the amelioration of long COVID symptoms, with more prominent effects observed in women. Although the changes in Treg population were not statistically significant in the G1899 group, the significant reduction observed in the placebo group suggests a potential protective effect of G1899 against Treg depletion.
Keywords: Flow cytometry; Immune function; Korean red ginseng; Long COVID.
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