Tocilizumab
Tocilizumab is a genetically-engineered monoclonal antibody humanized
from a mouse antihuman interleukin 6 (IL-6) receptor antibody. It has a
broad-spectrum immunomodulatory activity. It inhibits IL-6 from binding
to both membrane-bound and soluble receptors. IL-6 is a cytokine
produced by the various immune cells in response to molecular patterns
and affects multi-inflammatory cells. IL-6 is involved in
differentiation of CD-4 cells into Th-17 cells that play a significant
role in various immune-mediated diseases. SARS-COV-2 is thought to
induce massive cytokine storm, especially IL-6, therefore, the
inhibition of this IL-6 by tocilizumab significantly blocks this pathway
and consequent inflammatory sequelae associated with COVID-19 disease
(Karkkhur & Hasanreisoghi, 2019; Luo et al., 2020).
The clinical indications include rheumatoid arthritis, juvenile
idiopathic arthritis and non-infectious uveitis.
The adverse effects associated with tocilizumab include upper
respiratory tract infections, elevated liver enzymes,
hypercholesterolaemia, gastritis, mouth ulcers, gastrointestinal
perforation (Luo et al., 2020).