According to a story from Biotech 365, the biotechology company Kezar Life Sciences, Inc. recently announced that its experimental therapy KZR-616 has earned Orphan Drug designations from the US Food and Drug Administration (FDA). These designations are for treating dermatomyositis and polymyositis, which are related rare diseases that affect the muscles. Kezar Life Sciences is focused on finding breakthrough therapies in oncology and immune-mediated disorders.
Dermatomyositis is a long term, inflammatory disorder that primarily affects the skin and muscles. While the mechanism of the disease is an autoimmune response, the cause of dermatomyositis is generally unclear. Symptoms include a skin rash, which can take several forms, such as scaly papules on the finger joints, a v-shape on the chest, around the eyes with swelling, along the back and shoulders, and upper arms and thighs. People with dermatomyositis also experience progressive muscle weakness that begins in the thighs and shoulders, making movement difficult. To learn more about dermatomyositis, click here.
Polymyositis is a chronic condition characterized by inflammation of the muscles, with the endomysial layer of skeletal muscles being impacted. The cause is unknown, but it has been linked to cancer cases and celiac disease. Symptoms of polymyositis include muscle pain, muscle weakness, muscle atrophy, movement problems, problems swallowing, foot drop, enlarged lymph nodes, and fever. Symptoms tend to progress over time. The lung and heart may be affected in later stages. To learn more about polymyositis, click here.
About Orphan Drug Designation
Orphan Drug designation is typically reserved for therapies in development for the treatment of rare diseases, which is defined as any condition that affects less than 200,000 people in the US. The therapy must either fulfill an unmet medical need or display potential advantages in safety or efficacy in comparison to currently available treatments. This designation confers several benefits to the recipient company, such as the waiving of certain fees, tax breaks, and a period of market exclusivity lasting seven years if the drug is approved by the FDA.
KZR-616 is a selective inhibitor of immunoproteasome, making it potentially effective in addressing various drivers of immune-related inflammation. A phase 2 clinical study investigating this drug in patients with polymyositis and dermatomyositis is in the midst of recruiting patients.