Current State of Research about Chinese Herbal Medicines (CHM) for the Treatment of Coronavirus Disease 2019 (COVID-19): A Scoping Review

Abstract

Background: There is currently no effective treatment against coronavirus disease 2019 (COVID-19). The optimal selection of interventions targeting the virus is unknown. Therefore, evidence from randomized controlled trials (RCTs) to support specific treatment against COVID-19 is urgently needed. The use of Chinese herbal medicines (CHMs) might have a role in the treatment and symptomatic management of patients with COVID-19. It was aimed at providing an overview of the available evidence and ongoing trials concerning the effects of CHMs for the treatment of COVID-19. Methods: This is a narrative review of relevant studies. Searches were conducted to identify documents published till April 22, 2020. Electronic databases, evidence-based collections, websites of relevant organizations, and trial registries were consulted. Results: A total of 25 guidelines on the treatment of patients with COVID-19 were identified. Four guidelines provided recommendations on the use of CHMs; these guidelines were developed in China and South Korea and were based on the consensus of experts exclusively. The remaining 21 guidelines provided no guidance on CHMs. No finished RCTs of CHMs for the treatment of patients with COVID-19 was found. According to the evidence evaluated in this review, a Cochrane review of CHMs for severe acute respiratory syndrome and five uncontrolled observational studies of the effects of CHMs in patients with COVID-19, the effects of CHMs for COVID-19 are unknown. A total of 52 ongoing clinical trials of CHM interventions for the treatment of COVID-19 were found. These trials will be carried out mostly in China (n = 51). Forty (77%) of the ongoing trials will be randomized, whereas 12 (23%) have an unclear sequence generation procedure. Forty-seven trials (90%) will have a sample size <400 participants. Conclusions: To the authors' knowledge, only the Chinese and the South Korean guidelines recommend CHMs as a treatment option for patients with COVID-19. These guidelines base their recommendations on the consensus of experts. Clinical guidelines or health authorities from other countries do not provide advice on CHMs. Due to the absence of RCT, there is currently no reliable evidence on the effects of any specific CHM intervention for the treatment of patients with COVID-19. A high number of clinical trials of different herbal products are being currently conducted in China.