The US Food and Drug Administration has awarded Orphan Drug Designation to the drug lenabasum as a treatment for dermatomyositis. The use of lenabasum for treating this condition, and others, is being researched through clinical trials. The source statement can be found here, at the website of Corbus Pharmaceuticals.
According to the NIH, dermatomyositis refers to a group of muscle disorders. It is typically linked to chronic muscle inflammation and weakness, and a skin rash that is usually patchy and discoloured with red or blue. Patients diagnosed with dermatomyositis may also experience symptoms such as fever, weight loss, lung inflammation, calcium deposits, light-sensitivity, and others.
Although the cause of the condition is not currently well understood, researchers think that some people might have a genetic predisposition to developing it. Many doctors think that the body’s immune system response is also an underlying cause.
According to the source article, an estimated 80,000 people in the US, EU, and Japan are affected by dermatomyositis.
The drug lenabasum is currently being researched as an experimental treatment for dermatomyositis. It is a small-molecule drug that works by selectively binding to the cannabinoid receptor type 2 (CB2) on certain cells that are involved in the immune response. By activating these receptors, lenabasum is thought to cause inflammation to be reduced, faster bacterial clearance, and to stop fibrosis (thickening and scarring of connective tissues).
About Orphan Drug Designation
The US FDA awards Orphan Drug Designation to drugs that meet certain requirements. In order to be granted Orphan status, a drug needs to be intended to be used to support treatment, diagnosis, or prevention for a rare disorder, defined as one that affects fewer than 200,000 people in the US. Alternatively, Orphan status may be granted if the disorder affects more than 200,000 people but the developers do not expect to recover the costs of bringing the drug to market.
Orphan status is intended to support developers, and provides them with several benefits, including a longer period of marketing exclusivity than is normal, tax credits, and in some cases a waived prescription fee.
Research into Lenabasum
Studies using preclinical models of inflammation and fibrosis support lenabasum as a potentially effective treatment. Both preclinical studies and clinical studies in humans indicate that lenabasum is sufficiently safe and tolerable. Phase 2 studies of lenabasum for the treatment of cutaneous systemic sclerosis, cystic fibrosis, and dermatomyositis have found that the drug can be beneficial.