Journal of Pharmaceutics & Pharmacology
Research Article
Lysosomotropic Action of Amantadine: Basis for Treatment of COVID-19
Smieszek SP*, Przychodzen BP and Polymeropoulos MH
Vanda Pharmaceuticals Inc., Washington, DC, USA
*Address for Correspondence:
Smieszek SP, Vanda Pharmaceuticals Inc., 2200 Pennsylvania NW, Suite 300-
E, Washington, DC 20037, USA; Email: sandra.smieszek@vandapharma.com
Submission: 06 August 2020;
Accepted: 04 September 2020;
Published: 10 September 2020
Copyright: © 2020 Smieszek SP, et al. This is an open access article
distributed under the Creative Commons Attribution License, which
permits unrestricted use, distribution, and reproduction in any medium,
provided the original work is properly cited.
Abstract
SARS-coronavirus 2 is the causal agent of the COVID-19 outbreak. SARSCov-
2 entry into a cell is dependent upon binding of the viral Spike (S)
protein to cellular receptor and on cleavage of the spike protein by
the host cell proteases such as Cathepsin L and Cathepsin B (CTSL/B).
They are crucial elements of lysosomal pathway and both enzymes
are almost exclusively located in the lysosomes. CTSL disruption offers
potential for CoVID-19 therapies. The mechanisms of disruption include:
decreasing expression of CTSL, direct inhibition of CTSL activity and
modification of the CTSL environment (increase pH in the lysosome).
We have conducted a high throughput drug screen gene expression
analysis to identify compounds with the capacity to downregulate the
expression of CTSL/CTSB. One of the most significant results shown to
downregulate the expression of the CTSL gene is Amantadine(10uM).
We confirmed Amantadine’s lysosmal trapping capacity in an invitro
Lysosomal Trapping Assay. In addition, to downregulating CTSL,
Amantadine disrupts the lysosomal pathways, hence, interferes with
the capacity of the virus to replicate. It acts as a lysosomotropic agent
altering the CTSL functional environment. We propose that Amantadine
could decrease the viral load in SARS-CoV-2 positive patients and as
such it may serve as a potent therapeutic decreasing the replication
and infectivity of the virus likely leading to better clinical outcomes.
Clinical studies are currently needed to examine the therapeutic
efficacy of Amantadine in COVID-19 infection.