Bevacizumab in severe or critical patients with COVID‐19 pneumonia‐RCT  Drug: bevacizumab  China/COVID‐19 Pneumonia  118, all, 18–80  Treatment  Experimental; bevacizumab, group:
bevacizumab 500 mg + 0.9% NaCl 100 ml, intravenous drip
No intervention: control group  Not applicable  Primary: proportion of patients whose oxygenation index increased by 100 mmHg on the 7th day after admission  NCT04305106/Not yet recruiting, Mar12‐May31 2020