Acute myocarditis is a significant cause of acute heart failure and death in younger individuals and remains the most common cause of sudden cardiac death in people under 35 years of age. The most recent data from the ‘Global Burden of Disease Study’ suggests that the prevalence of myocarditis is approximately 22 per 100,000 population, qualifying the condition as an orphan disease in the U.S. and in Europe.
Acute myocarditis is characterized by inflammation in the heart muscle (myocardium). It has many causes, but the most common is a viral infection. In most patients the immune system is effective in clearing the virus in five to seven days, inflammation subsides, and the individual makes a full recovery. In a proportion of patients, however, the inflammation in the heart persists – perhaps as an auto-immune process – and causes decreased heart function with symptoms and signs of heart failure. In some cases, this becomes progressive and leads to a chronic dilated cardiomyopathy which is the most common reason for heart transplantation.
Since people with acute myocarditis have impaired heart function, its treatment is based on standard-of-care recommendations for heart failure. This includes diuretics, ACE inhibitors, angiotensin receptors blockers, beta blockers, and aldosterone inhibitors. For those with a fulminant presentation, intensive care is often required, with the use of inotropic medications (to increase the force of the heart muscle contraction) and occasionally, heart-lung bypass or ventricular assist devices. There is otherwise no specific treatment for acute myocarditis although some patients have responded to immuno-suppressive therapy (azathioprine) in combination with steroids, but the data are not conclusive enough for this to be the recommended therapy. Immune-modulation therapy with immune globulin has been trialed but without clear success.
Based on the large body of experimental evidence of the powerful anti-inflammatory activity of CBD in models of cardiovascular disease, Cardiol believes there is a significant opportunity to develop a potential breakthrough therapy for acute myocarditis that would be eligible for designation as an orphan drug. In the United States, an orphan drug designation is granted for pharmaceuticals being developed to treat medical conditions affecting fewer than 200,000 people. These conditions are referred to as orphan diseases. The assignment of orphan status to a disease and to drugs developed to treat it is a matter of public policy in many countries and has yielded medical breakthroughs that might not otherwise have been achieved. In the U.S. and the European Union, orphan drugs are eligible for accelerated marketing approvals and companies developing orphan drugs typically receive other incentives, including a prolonged period of market exclusivity that can extend over seven years, during which the drug developer has sole rights to market the drug.