Tocilizumab Shows Promise for Lessing Cytokine Storm for COVID-19 Patients

A drug often used to treat rheumatoid arthritis reduces mortality when given to patients with severe COVID-19. The monoclonal antibody Tocilizumab appears to help stem cytokine storms that make the novel coronavirus so much more deadly, according to recent meta-analyses. Here is more information.

FORT LAUDERDALE, FL – Tocilizumab, often used in rheumatoid arthritis treatment,  is a monoclonal antibody that inhibits the binding of interleukin-6 (IL-6) to its receptor (IL-6R). That helps prevents IL-6 signal transduction to inflammatory mediators that summon B and T cells and has been touted as a way to dampen the cytokine storms that are so dangerous for COVID-19 patients.

A review from ¹Nova Southeastern University’s College of Osteopathic Medicine looked at cytokine storm --also known as cytokine release syndrome (CRS) -- , a systemic inflammatory response that can be triggered by an infection in severe cases of COVID-19. Published in Recent Patents on Anti-Infective Drug Discovery, their review evaluates several published studies that have implemented Tocilizumab (TCZ), an IL-6 receptor antibody (US20120253016A1), in COVID-19 treatment.

https://pubmed.ncbi.nlm.nih.gov/32962623/

In those studies, outcomes and biomarkers of patients treated with TCZ are compared to patients treated with standard of care regimens. Past research has suggested that interleukin6 (IL-6), a prominent inflammatory cytokine involved in CRS in various inflammatory conditions, could have a vital role in the underlying mechanism involved in debilitating SARS-CoV-2 infections and could serve as a viable treatment target.

Researchers systematically reviewed the literature to answer the following research questions: 1) does IL-6 (receptor) antagonist therapy reduce mortality in COVID-19 patients compared to patients not treated with IL-6 (receptor) antagonists and 2) is there an increased risk of side effects in COVID-19 patients treated with IL-6 (receptor) antagonists compared to patients not treated with IL-6 (receptor) antagonists?.

A search of PubMed, PMC PubMed Central, MEDLINE, WHO COVID-19 Database, Embase, Web-of-Science, COCHRANE LIBRARY, Emcare and Academic Search Premier until June 20, 2020, retrieved 743 unique titles of which 10 studies --all on tocilizumab-- comprising 1358 patients were included.

Meta-analysis indicates that the tocilizumab group had lower mortality than the control group. The risk ratio (RR) was 0.27 95%CI 0.12 to 0.59 and the risk difference (RD) was 12% 95%CI 4.6% to 20% in favor of the tocilizumab group. With only a few studies available there were no differences observed regarding side effects, the authors write.

 Our results showed that mortality was 12% lower for COVID-19 patients treated with tocilizumab compared to COVID-19 patients who were not treated with tocilizumab,” researches explain. “The number needed to treat was 11, suggesting that for every 11 (severe) COVID-19 patients treated with tocilizumab 1 death is prevented. These results require confirmation by randomized controlled trials.”

Another meta-analysis from Dutch researchers had similar results. Writing in Clinical Infectious Diseases, the authors from Leiden University Medical Center determined that Our results showed that mortality was 12% lower for COVID-19 patients treated with tocilizumab compared to COVID-19 patients who were not treated with tocilizumab. 

The number needed to treat was 11, suggesting that for every 11 (severe) COVID-19 patients treated with tocilizumab 1 death is prevented. These results require confirmation by randomized controlled trials,” researchers noted.