Since the outbreak of the COVID-19, a series of basic and clinical researches on Lianhua Qingwen Capsules against SARS-CoV-2 have been carried out, forming a chain of evidence for treatment of COVID-19 with Lianhua Qingwen with reliable effect on "cell-animal-clinical". Basic research results show that Lianhua Qingwen have stable in vitro antivirus effect on COVID-19, whether wild-type or subsequent multiple mutants, can significantly improve the cytopathic effect caused by virus infection, and can inhibit the release of proinflammatory factors. At present, in vitro experimental results of Omicron variant have been published, which has good effect. The animal experiment on Lianhua Qingwen Capsules against Omicron is carrying out; the international multicenter clinical research has been carried out in several countries.

The research results of "Efficacy and Safety of Lianhuaqingwen Capsules for the Prevention of Coronavirus Disease 2019: A Prospective Open-Label Controlled Trial" published on the Evidence-based Complementary and Alternative Medicine show that Lianhua Qingwen Capsules can significantly reduce the infection rate of close contacts and the incidence rate of symptoms for patients who are positive in nucleic acid test, especially the incidence rate of fever, so as to provide new therapeutic regimens for suspected cases and close contacts of COVID-19.

In the Diagnosis and Treatment Protocol for COVID-19 (Trial Version 9) published by Chinese government on March 14, Lianhua Qingwen Capsules are recommended for prevention and control of the population under medical observation and mild and general patients during clinical treatment. Lianhua Qingwen Capsules have been recommended for treatment of COVID-19 for six times in the national protocol since the outbreak of COVID-19.