FDA approved firdapse to treat lambert-eaton muscular weakness syndrome

The FDA today approved Firdapse (amifampridine), a tablet from Catalyst pharmaceuticals, for use in the treatment of adult lamborg-eaton myasmus syndrome (LEMS).LEMS is a rare autoimmune disease that affects the connections between nerves and muscles, leading to weakness and other symptoms.This is the first time FDA has approved a drug for LEMS.
"For this rare disease, there has long been a need for treatment," said Dunn, md, director of neurology products at the FDA's center for drug evaluation and research. "LEMS patients have significant weakness and fatigue, which often leads to significant difficulties in daily activities."

In LEMS patients, the body's own immune system attacks neuromuscular junctions (the junctions between nerves and muscles), damaging the ability of nerve cells to send signals to muscle cells.LEMS may be associated with other autoimmune diseases, but it is more common in cancer patients, such as small-cell lung cancer, whose onset is earlier or detected at the same time of cancer diagnosis.It is estimated that three out of every one million people worldwide suffer from LEMS.

Two clinical trials studied the effectiveness of Firdapse, in which 64 adults were treated with either Firdapse or a placebo.Both studies examined the quantitative myasthenia gravis score (a physician's 13-item classification scale for muscle weakness) and the subjects' overall impression score (a patient's overall impression score of the impact of the treatment studied on their physical health, on a 7-point scale).In both tests, patients treated with Firdapse benefited more than those treated with a placebo.

The most common side effects in patients in clinical trials were burning or tingling (paresthesia), upper respiratory tract infection, abdominal pain, nausea, diarrhea, headache, elevated liver enzymes, back pain, hypertension, and muscle spasm.Seizures were observed in patients with no history of seizures.If the patient has allergic reactions such as rashes, urticaria, itching, fever, swelling or dyspnea, the medical staff should be informed immediately.

The FDA granted priority approval and breakthrough treatment to the drug's marketing applications.Firdapse also received orphan drug qualification, which provides incentives to help and encourage the development of drugs to treat rare diseases.