Traditional Vietnamese medicine Kovir capsule for non-severe COVID-19 patients: A phase III double-blind randomized controlled trial.

The number of COVID-19 infections is still increasing with the omicron variant. Although vaccination has shown its effectiveness, efficacious treatments are still required. Kovir, a Vietnamese herbal medicine, has shown potential effects for non-severe COVID-19 patients in terms of symptom resolution and prevention of disease progression in previous studies. This phase-3 trial evaluated the safety and efficacy of Kovir for non-severe COVID-19 adults. Participants were randomized to the Kovir (381 patients) or placebo (192 patients) groups. Outcomes were progression to severe/critical COVID-19, a daily symptom score based on 11 pre-defined symptoms, time to symptom resolution, a negative reverse transcription polymerase chain reaction, an EQ-5D-5L quality of life (QOL) score, and serious adverse events. Only one patient (in the placebo group) progressed to severe COVID-19, thus we could not conclude the effect of Kovir on the prevention of disease progression. Kovir significantly reduced time to symptom resolution (median: 7 vs. 11 days, hazard ratio [95% confidence interval]: 2.03 [1.66-2.48]) compared to placebo. Kovir also increased the QOL score on days 7 and 14. No safety concerns were observed. To conclude, Kovir is safe and facilitates symptom relief for non-severe COVID-19 patients. We advocate using Kovir in the early phase of COVID-19 for non-severe adult patients.