Host Response Mediators in Coronavirus (COVID-19) Infection - Is There a Protective Effect of Losartan and Other ARBs on Outcomes of Coronavirus Infection?

SARS-CoV-2 is a member of a class of viruses: angiotensin converting enzyme 2 (ACE2)-binding viruses that study calls "ABVs". The World Health Organization (WHO) and others are performing randomized controlled trials (RCTs) of vaccines and novel antivirals to address SARS-CoV-2 directly. However, the critical illness complications of COVID-19 are caused in part by SARS-CoV-2's binding and inhibiting ACE2 and the consequent host response. ACE 2 is the receptor for H1N1, H5N1, and SARS-CoV-2. After binding ACE2, SARS-CoV-2 is endocytosed, and surface ACE2 is down-regulated, increasing angiotensin II (ATII a potent vasoconstrictor) in COVID-19. The original ARBs limits lung injury in murine influenza H7N9 and decreases viral titre and RNA. Study has a unique opportunity to complement vaccine and anti-viral RCTs with an RCT modulating the host response using an angiotensin II type 1 receptor blocker (ARBs) to decrease the mortality of hospitalized COVID-19 patient.