RAS inhibition and COVID-19: more questions than answers ?

Since the beginning of the COVID-19 pandemic and the first reports of an increased mortality among patients with COVID-19 treated for hypertension, the potential role of renin–angiotensin system (RAS) blockers on the severity of the disease has been questioned. Although RAS blockers have been associated with better outcomes in pneumonia models, they might also upregulate the expression of angiotensin-converting enzyme 2 (ACE2) receptor, which acts as a co-receptor for human cell infection by SARS-CoV-2 through the binding with the spike protein. Following neutral and reassuring large observational studies and meta-analyses, two randomised trials have been done and published: the BRACE CORONA and the REPLACE COVID trials. Both studies concluded an absence of effect of chronic RAS blockade on the course of COVID-19, as previously observed in observational studies

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The ACEI-COVID study adds more data to the existing evidence showing that RAS blockers should not be systematically discontinued in patients with COVID-19, but it leaves us also with more questions than answers.