Epigallocatechin-3-gallate (EGCG) is a major polyphenol of green tea that possesses a wide variety of actions, such as anti-inflammatory, anti-fibrotic, pro-apoptotic, anti-tumorous, and metabolic effects via modulation of a variety of intracellular signaling cascades. In addition, preclinical studies have also emphasized the antiviral activity of epigallocatechin-3-gallate (EGCG), including SARS-CoV-2. In previous studies, we found that EGCG can prevent and cure radiation- induced normal tissue damage in tumor patients. In clinical studies, we found that EGCG can prevent and treat radiation-induced acute radiation esophagitis, acute radiation skin injury, acute radiation oral mucositis with high safety. At the same time, the phase I clinical trial designed by us has confirmed the safety and efficacy of EGCG in the treatment of interstitial pneumonia.

The Phase II study was conducted with a randomized, controlled, placebo dose determined by Phase I. the subjects were divided into two groups (experimental group and placebo group). To observe the effectiveness of EGCG, the researchers will use both clinician assessment and patient self-assessment. Primary endpoint: change in imaging (chest CT) before and after treatment. Secondary evaluation endpoints: 1 Further evaluation of the safety of EGCG. 2 The degree of symptom improvement . 3 Changes in laboratory testing indicators.

Inclusion Criteria:

• Diagnosed malignant tumors by pathology or cytology
• COVID-19 with a confirmed positive polymerase chain reaction or antigen test result for SARS-CoV-23
• moderate-to-severe COVID-19 pneumonia (defined as any radiographic evidence of pulmonary infiltrates and oxygen saturation >94% on room air)
• Pulmonary function of the patient can be treated with aerosol inhalation for 7 days

Exclusion Criteria:

• Current or recent progresses rapidly and may develop into a Critical illness with coronavirus in a short period of time
• Caused by other viruses such as cytomegalovirus, as well as pneumocystis pneumonia, pulmonary edema, aspiration pneumonia and acute interstitial pneumonia
• Any condition including medical, emotional, psychiatric, or logistical that, in the opinion of the Investigator would preclude the participant from adhering to the protocol or would increase the risk associated with study participation
• known allergy or hypersensitivity to EGCG

CT evaluations were performed by a separate radiologist blinded to both treatment allocation and potential imaging artifacts. Subjective endpoints (e.g., COVID-19 symptoms) were collected via patient self-reporting, entirely recorded by the participants themselves to minimize human interference.