In clinical institutions that enroll patients with coronavirus disease 2019, three arms, multi-center, randomized and controlled methods are adopted.

Patients are divided into three groups, favipiravir combined with tocilizumab group, favipiravir group and tocilizumab group. 150 patients are expected to be enrolled and the cases are allocated according to the ratio of 3( favipiravir combined with tocilizumab group): 1(favipiravir group): 1(tocilizumab group).