FDA Approves Catalyst Pharma's Drug To Treat Rare Autoimmune Disorder

(RTTNews) - The U.S. Food and Drug Administration approved Firdapse or amifampridine tablets for the treatment of Lambert-Eaton myasthenic syndrome or LEMS in adults. LEMS is a rare autoimmune disorder that affects the connection between nerves and muscles and causes weakness and other symptoms in affected patients. This is the first FDA approval of a treatment for LEMS. The FDA granted the approval of Firdapse to Catalyst Pharmaceuticals Inc. (CPRX).

In people with LEMS, the body's own immune system attacks the neuromuscular junction (the connection between nerves and muscles) and disrupts the ability of nerve cells to send signals to muscle cells. LEMS may be associated with other autoimmune diseases, but more commonly occurs in patients with cancer such as small cell lung cancer, where its onset precedes or coincides with the diagnosis of cancer. The prevalence of LEMS is estimated to be three per million individuals worldwide.

The most common side effects experienced by patients in the clinical trials were burning or prickling sensation (paresthesia), upper respiratory tract infection, abdominal pain, nausea, diarrhea, headache, elevated liver enzymes, back pain, hypertension and muscle spasms. Seizures have been observed in patients without a history of seizures. Patients should inform their health care provider immediately if they have signs of hypersensitivity reactions such as rash, hives, itching, fever, swelling or trouble breathing.