Efficacy and safety of Tocilizumab, plasmapheresis and their combination in severe COVID-19: A randomized clinical trial

Abstract

Background: This study sought to evaluate and compare the effectiveness of plasmapheresis, Tocilizumab, and Tocilizumab with plasmapheresis treatment on the removal of inflammatory cytokines and improvement clinically of patients with severe COVID-19 in Intensive Care Units (ICU) due to the association between increased cytokine release and the severity of COVID-19.

Methods: This clinical trial study was conducted in three treatment arms in Iran. All patients received standard care and randomization into one of three treatment groups; Tocilizumab (TCZ) alone, plasmapheresis alone, or a combination of Tocilizumab and plasmapheresis. Demographics, clinical evaluation, oxygenation status, laboratory tests and imaging data were evaluated in the three groups and re-checked 48 h after the end of treatment trials. Primary outcomes were oxygenation status, the need for mechanical ventilation and the rate of death.

Results: Ninety-four patients were included in the trial after meeting the eligibility requirements. Twenty-eight patients received Tocilizumab alone, 33 had plasmapheresis alone, and 33 received both Tocilizumab and plasmapheresis. Baseline characteristics did not differ between three groups that included demographic, clinical and laboratory parameters. Following therapy, there was no difference between the three groups for CRP, ferritin, d-dimer, IL-6, pro-calcitonin and neutrophil to lymphocyte ratio (NLR) (P > 0.05). While a significant reduction was found in CRP levels within each group (32.04 ± 42.43 to 17.40 ± 38.11, 51.28 ± 40.96 to 26.36 ± 33.07 and 41.20 ± 34.27 to 21.56 ± 24.96 in the tocilizumab, plasmapheresis, and combined group, respectively) (p < 0.05), procalcitonin levels were elevated significantly in the Tocilizumab group (0.28 ± 0.09 to 0.37 ± 0.11) (p < 0.05). Clinically there was no difference between the three groups following treatment for O₂ saturation levels with supplementary oxygen at discharge, endotracheal intubation rate, use of NIVPP, mortality, mean hospital and ICU length of stay (p > 0.05).

Conclusion: Study results showed that the reduction of serum inflammatory markers, the rate of intubation and therapeutic complications including death were no different between the three groups; however, CRP levels were significantly reduced in all three groups, indicating that the interventions reduced inflammation likely through a reduction in the cytokine storm, though clinical outcomes were unaffected.

Keywords: COVID-19; Efficacy; Plasmapheresis; Safety; Tocilizumab.