Angiotensin 1-7 in severe COVID-19 patients: a phase 1 clinical trial (preprint)

Background: The coronavirus-related disease (COVID-19) is mainly characterized by a respiratory involvement, with few available therapeutics for critically cases. The renin-angiotensin system (RAS) has a relevant role in the pathogenesis of COVID-19, as the virus enter host's cells via the angiotensin-converting enzyme 2 (ACE2) and RAS disequilibrium promote inflammation and fibrosis. Exogenous angiotensin-(1-7) might modulate RAS in COVID-19 patients; however, no data on its safety are available in this setting. Methods: This investigator-initiated, open label, phase I clinical trial was conducted to test the safety of intravenous administration of Angiotensin-(1-7) in severe COVID-19 patients admitted in two intensive care units (ICU) in Belo Horizonte, Brazil. In addition to standard of care, intravenous administration of Angiotensin-(1-7) was started at 5 mcg/Kg*day and increased to 10 mcg/Kg*day after 24 hours and continued for a maximum of 7 days or until ICU discharge. The rate of serious adverse events (SAEs) served as the primary outcome of the study. Results: Between August and December 2020, 28 patients were included (mean age of 55.8 + or -12.0 years). All but one patient underwent dose escalation after 24 hours and 8 (28.5%) received the treatment until day 7. No significant differences in mean blood pressure and heart rate were observed before and after the initiation of the drug. During the period of intervention, 5/28 (17.8%) patients required vasopressors, 4 at low dose norepinephrine (i.e. <0.05 mcg/kg*min), while one patient required higher doses because of septic shock. One patient presented with sinus bradycardia, which was considered possibly related to the study drug and resolved after discontinuation. Six patients (21.4%) died before ICU discharge. Conclusions: Intravenous infusion of Angiotensin-(1-7) up to 10 mcg/Kg*day was safe in severe COVID-19 patients and could represent a potential therapeutic strategy in this setting.

Increased circulating levels of angiotensin-(1-7) in severely ill COVID-19 patients (preprint)

The mono-carboxypeptidase Angiotensin-Converting Enzyme 2 (ACE2) is an important player of the renin-angiotensin system (RAS). ACE2 is also the receptor for SARS-CoV-2, the new coronavirus that causes COVID-19. It has been hypothesized that following SARS-CoV-2/ACE2 internalization Ang II level would increase in parallel to a decrease of Ang-(1-7) in COVID-19 patients. In this preliminary report, we analyzed the plasma levels of angiotensin peptides in 19 severe COVID-19 patients and 19 non-COVID-19 volunteers. Unexpectedly, a significant increase in circulating Ang-(1-7) and lower Ang II plasma level were found in critically ill COVID-19 patients. Accordingly, an increased Ang-(1-7)/ Ang II ratio was observed in COVID-19 suggesting a RAS dysregulation toward an increased formation of Ang-(1-7) in these patients.