COVID-19 Therapeutics Why Not Angiotensin Receptor Blockers (ARBs)?

Overactivity of the renin-angiotensin-aldosterone system (RAAS) is a consistent feature of COVID-19 as indicated by high concentrations of angiotensin II (Ang II) in lungs and other tissues. Virus-induced downregulation of angiotensin-converting enzyme-2 (ACE2) explains the raised Ang II levels. Available evidence points to the crucial role of Ang II in the pathogenesis of coronavirus disease. The proinflammatory, immune stimulant, and procoagulant effects exhibited by the peptide at high tissue levels explain lung injury, a characteristic feature of severe COVID-19. Angiotensin II (Ang II) inhibitors [both the angiotensin-converting enzyme inhibitors (ACEIs) and the angiotensin receptor blockers (ARBs)] constitute the logical therapy for established COVID-19 infection. While ACEIs help to lower Ang II levels in the tissues, ARBs antagonize the effects of the peptide on the target tissues. Of the two, ARBs offer a better choice because of the minimal adverse effects of dry cough and angioedema. The effectiveness of Ang II inhibitors in COVID-19 is well supported by their protective effect against lung injury in animals induced by the virus spike protein as well as the clinical improvement of shortened hospital stay and reduced mortality in observational studies in humans. A unique feature of these agents is that mutations of the coronavirus 2 (CoV-2) would have little impact on their effectiveness since they do not interfere with the host cell entry of the virus or its replication. Expectedly, the agents might retain their usefulness against variant strains, including "ο" and its subvariants. The overall safety of Ang II inhibitors has been well established beyond doubt since they have been in use for years in the management of cardiovascular (CV) diseases, diabetes mellitus, and chronic kidney disease (CKD). Regular use of ARBs in all patients who are COVID-19 positive and symptomatic (mild, moderate, or severe) offers a good option worth serious consideration. How to cite this article: S HT. COVID-19 Therapeutics Why Not Angiotensin Receptor Blockers (ARBs)? J Assoc Physicians India 2023;71(11):71-75.