An Efficacy and Safety Study of Jaktinib Hydrochloride Tablets in the Treatment of Severe Novel Coronavirus Pneumonia

Inclusion Criteria: * Aged 18 to 80 years old (including threshold), regardless of gender; * There is a history of novel coronavirus antigen- or nucleic acid-positive infection within 1 week; * HRCT is consistent with the manifestation of viral pneumonia (judged by the investigator) * Participants who voluntarily sign informed consent. Exclusion Criteria: * Participants who cannot take orally, or are suspected to be allergic to Jaktinib hydrochloride, similar drugs or their excipients, or have severe gastrointestinal dysfunction that affects drug absorption; * Critical pneumonia patients with other organ failure requiring ICU monitoring and treatment; * Participants who have received the following treatments within the specified time window before randomization: 1. participants have received Janus kinase (JAK) inhibitor, interleukin 6 (IL-6) inhibitor, IL-1 inhibitor, tumor necrosis factor (TNF) inhibitor, T cell or B cell depletion agent, interferon and other immunosuppressive drugs within the first two weeks of randomization, except glucocorticoid; 2. Systematically used CYP 3A4 potent inhibitor or potent inducer in the first five drug half lives at random; * Immune deficiency; * Participants who have received novel coronavirus vaccine within 1 week before randomization; * Prior to randomization, there were the following active and uncontrolled infections: tuberculosis, HIV, syphilis, mycoplasma, chlamydia, parasites, and viral infections other than SARS CoV-2 that required systemic anti-infection treatment; * Renal diseases requiring dialysis treatment; * Pregnant and lactating women; * Any other participants that were considered unsuitable by the investigator.