Cardiol Therapeutics Receives FDA Clearance of Investigational New Drug (IND) Application for Phase II Clinical Trial of CardiolRx™ for Acute Myocarditis

Oakville, ON – August 24, 2021 – Cardiol Therapeutics Inc. (NASDAQ: CRDL) (TSX: CRDL) (“Cardiol” or the “Company”), a clinical-stage biotechnology company focused on developing innovative anti-inflammatory therapies for the treatment of cardiovascular disease, is pleased to announce that the U.S. Food and Drug Administration (FDA) has provided clearance to proceed with the Company’s Investigational New Drug (IND) application to commence a Phase II, multi- center, double-blind, randomized, placebo-controlled trial designed to study the safety and tolerability of CardiolRx™, as well as its impact on myocardial recovery in patients presenting with acute myocarditis.

Myocarditis is an acute inflammatory condition of the myocardium, characterized by inflammation of the heart muscle, which may result in chest pain, impaired cardiac function, atrial and ventricular arrhythmias, and conduction disturbances. Although the symptoms are often mild, myocarditis remains an important cause of acute and fulminant heart failure and is the most common cause of sudden cardiac death in people less than 35 years old. In addition, some patients proceed to develop chronic dilated cardiomyopathy which continues to be the leading indication for cardiac transplantation. Although viral causes of myocarditis are the most common, myocarditis can result from a broad range of infections and can be caused by certain drugs, including chemo-therapeutic agents used to treat several common cancers. Myocarditis has also been described as a complication of COVID-19 and, more recently, has been reported as a rare complication associated with certain vaccines for COVID-19.

Cardiol’s acute myocarditis study is expected to enroll 100 patients at clinical centers in the United States and Europe. The primary endpoints of the trial, which will be evaluated after 12 weeks of double-blind therapy, consist of the following cardiac magnetic resonance measures: left ventricular function (ejection fraction and longitudinal strain) and myocardial edema (extra- cellular volume), each of which has been shown to predict long-term prognosis of patients with acute myocarditis.

The study has been designed by an independent steering committee comprising distinguished thought leaders in heart failure and myocarditis from international centers of excellence, including: the Cleveland Clinic, the Mayo Clinic, the Houston Methodist DeBakey Heart and Vascular Center, the University of Ottawa Heart Institute, McGill University Health Centre, University of Pittsburgh Medical Center, Charité Hospital Berlin, and the University of South Florida Health Morsani College of Medicine/Tampa General Hospital Heart and Vascular Institute.

“IND clearance to proceed with our Phase II clinical trial of CardiolRx in patients with acute myocarditis represents another major milestone for Cardiol as we continue to pursue the development of new treatment options for patients with inflammatory heart disease,” said David Elsley, President and Chief Executive Officer of Cardiol Therapeutics. “We look forward to further studying the cardioprotective potential of CardiolRx in this rare but potentially devastating condition that remains an underdiagnosed cause of acute heart failure, sudden death, and chronic dilated cardiomyopathy.”

Given the risk of significant heart failure associated with acute myocarditis, current intervention includes drugs commonly administered for heart failure. However, no generally accepted treatment exists for acute myocarditis. Some patients respond to immunosuppressive therapy in combination with steroids, or immune-modulation therapy using immune globulin. Nevertheless, the evidence for these therapies is insufficient to support adoption as standard of care and they carry high risk for significant adverse effects.

Based on the large body of experimental evidence of the anti-inflammatory and cardioprotective properties of cannabidiol in models of cardiovascular disease, the Company believes there is a significant opportunity to develop an important new therapy for acute myocarditis that would be eligible for designation as an orphan drug. The U.S. orphan drug program was created to offer companies significant incentives, including accelerated regulatory review and approval, to develop treatments for diseases that affect fewer than 200,000 people in the U.S. The program was successfully utilized to support the first FDA approval of cannabidiol for the treatment of rare pediatric epilepsy syndromes. Cardiol believes there is a similar opportunity to develop its CardiolRx formulation as an orphan drug for the treatment of acute myocarditis, for which there is currently no accepted standard of care.