Tocilizumab May Be a Key in Therapy for Cytokine Release Syndrome in Older Patients With Severe Symptoms of COVID-19

Abstract Background Older adults are more susceptible to the novel coronavirus disease 2019 (hereafter, COVID-19) and more likely to develop severe illness. Cytokine release syndrome (CRS) may be an important factor in the development of severe disease in patients with COVID-19. Interleukin-6 (IL-6) is an important cytokine in CRS, and tocilizumab can block the IL-6 receptor. In this study, we analyzed the therapeutic effects and safety of tocilizumab on CRS in older patients with severe COVID-19. Methods Between February 10 and March 21, 2020, a total of 19 patients with severe or critical COVID-19 aged ≥ 60 years met the study inclusion criteria at Tongji hospital in Wuhan city, Hubei Province, China. Patients were divided into two groups: 1. The tocilizumab group, whose IL-6 levels exceeded the upper limit of normal by > 10-fold; and 2. The no tocilizumab group, with 1L-6 levels < 10-fold the upper normal limit. Results Patients in the tocilizumab group were older (73.20 ± 4.44 vs. 66.21 ± 5.06 years, P = 0.014); had lower lymphocyte counts (0.71 ± 0.18 vs. 1.18 ± 0.59 × 109/L, P = 0.016); and higher high-sensitivity C-reactive protein (hsCRP) levels (94.04 ± 57.24 vs. 51.65 ± 45.37 mg/L, P = 0.035). The increases in ferritin (FER) and hsCRP levels in patients in the tocilizumab group were marked. Except in one patient who died, IL-6, FER, and hsCRP levels, and the neutrophil/lymphocyte ratio, in the remaining four patients decreased following treatment with tocilizumab. Further, patient computerized tomography scan results improved after 3–8 days of tocilizumab treatment. Tocilizumab did not cause any serious adverse reactions. There were no differences in mortality or days until lung computerized tomography improvement between the two groups. The total mortality rate was 10.53%. Conclusions Our results support the therapeutic efficacy and safety of tocilizumab on older patients with severe COVID-19.