Early use of tocilizumab in the prevention of adult respiratory failure in SARS-CoV-2 infections and the utilization of interleukin-6 levels in the management

Abstract

Respiratory failure in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection appears related to cytokine release syndrome that often results in mechanical ventilation (MV). We investigated the role of tocilizumab (TCZ) on interleukin-6 (IL-6) trends and MV in patients with SARS-CoV-2. In this longitudinal observational study, 112 patients were evaluated from 1 February to 31 May 2020. TCZ was administered followed by methylprednisolone to patients with >3L oxygen requirement and pneumonia severity index score ≤130 with computed tomography scan changes. IL-6, C-reactive protein (CRP), ferritin, lactate dehydrogenase (LDH), D-dimer, and procalcitonin were monitored on days 0, 3, and 6 of therapy. Statistical analyses were performed with significance ≤0.05. Eighty out of 112 SARS-CoV-2-positive patients (45 males, 56.96%; 34 females, 43.04%) were included in this study. Seven patients expired (8.75%) and nine patients required MV (11.25%). Median IL-6 levels pre-administration of TCZ was 342.50 (78.25-666.25) pg/mL compared with post-administration on day 3 (563; 162-783) pg/mL (P < .00001). On day 6, the median dropped to 545 (333.50-678.50) pg/mL compared with day 3 (P = .709). CRP, ferritin, LDH, and D-dimer levels were reduced after TCZ therapy. Early use of TCZ may reduce the need for MV and decrease CRP, ferritin, LDH, and D-dimer levels. The sequential use of methylprednisolone for 72 hours seems to potentiate the effect and prolong the suppression of the cytokine storm. IL-6 levels may be helpful as a prognostic tool.

Keywords: IL-6 levels; SARS-CoV-2; early treatment; mechanical ventilation; outcomes.