COVID-19: Famotidine, Histamine, Mast Cells, and Mechanisms.

Abstract

SARS-CoV-2 infection is required for COVID-19, but many signs and symptoms of COVID-19 differ from common acute viral diseases. SARS-CoV-2 infection is necessary but not sufficient for development of clinical COVID-19 disease. Currently, there are no approved pre- or post-exposure prophylactic COVID-19 medical countermeasures. Clinical data suggest that famotidine may mitigate COVID-19 disease, but both mechanism of action and rationale for dose selection remain obscure. We have investigated several plausible hypotheses for famotidine activity including antiviral and host-mediated mechanisms of action. We propose that the principal mechanism of action of famotidine for relieving COVID-19 symptoms involves on-target histamine receptor H2 activity, and that development of clinical COVID-19 involves dysfunctional mast cell activation and histamine release. Based on these findings and associated hypothesis, new COVID-19 multi-drug treatment strategies based on repurposing well-characterized drugs are being developed and clinically tested, and many of these drugs are available worldwide in inexpensive generic oral forms suitable for both outpatient and inpatient treatment of COVID-19 disease.

• Authors: Robert W Malone, Philip Tisdall, Philip Fremont-Smith, Yongfeng Liu, Xi-Ping Huang, Kris M White, Lisa Miorin, Elena Moreno, Assaf Alon, Elise Delaforge, Christopher D Hennecker, Guanyu Wang, Joshua Pottel, Robert V Blair, Chad J Roy, Nora Smith, Julie M Hall, Kevin M Tomera, Gideon Shapiro, Anthony Mittermaier, Andrew C Kruse, Adolfo García-Sastre, Bryan L Roth, Jill Glasspool-Malone, Darrell O Ricke
• Journal: Frontiers in pharmacology (Front Pharmacol) Vol. 12 Pg. 633680 ( 2021) ISSN: 1663-9812 [Print] Switzerland
• PMID: 33833683 (Publication Type: Journal Article)
• Copyright: Copyright © 2021 Malone, Tisdall, Fremont-Smith, Liu, Huang, White, Miorin, Moreno, Alon, Delaforge, Hennecker, Wang, Pottel, Blair, Roy, Smith, Hall, Tomera, Shapiro, Mittermaier, Kruse, García-Sastre, Roth, Glasspool-Malone and Ricke.