Effect of Subcutaneous Tocilizumab on Mortality in Patients With COVID-19: A Meta-analysis of Retrospective Cohort Studies

Abstract

To the Editor: Several case reports and retrospective cohort studies have described the experience with intravenous (IV) tocilizumab (TCZ) in treating severe coronavirus disease 2019 (COVID-19),1–3 with results showing improved clinical symptoms and lung functions. However, to the best of our knowledge, the data on subcutaneous (SC) use of TCZ are lacking. Therefore, we performed a meta-analysis comparing the mortality rate among patients with COVID-19 who received subcutaneous tocilizumab versus intravenous tocilizumab. After a literature search, we found 2 studies that compared the efficacy of SC TCZ and IV TCZ were included in this analysis.2,3 In the study by Guaraldi et al,3 they assessed the use of tocilizumab (91 patients were given subcutaneously with a dose of 324 mg in total and 88 patients were given intravenously with a dose of 8 mg/ kg body weight, up to a maximum of 800 mg) plus standard care for hospitalized patients with severe COVID-19 pneumonia. In the study of Kaminski et al,2 they compared the effect of subcutaneous (324 mg in total) and intravenous tocilizumab (400 mg) for hospitalized patients with COVID-19. The outcomes including 7-day mortality, 14to 28-day mortality, and requirement for mechanical ventilation. Overall, 151 and 153 received SC TCZ and IV TCZ, respectively. In the pooled analysis of 2 studies, the 7-day mortality rate was 23.3% (35/150) in the SC TCZ group and 19.0% (29/153) in the IV TCZ group. In addition, the 14to 28-day mortality rate was 54.4% (81/ 149) in the SC TCZ group and 45.0% in the IV TCZ