The US Food and Drug Administration (FDA) has approved Jacobus’ Ruzurgi (amifampridine) tablets for the treatment of Lambert-Eaton myasthenic syndrome (LEMS) in patients six to less than 17 years of age.

The approval marks the first FDA approval of a treatment specifically for paediatric patients with LEMS, as currently the only other treatment approved for LEMS is approved for use in adults.

The approval was based on a placebo-controlled withdrawal study of 32 adult patients in which patients were taking Ruzurgi for at least three months prior to entering the study, using pharmacokinetic modelling and simulation to identify the dosing regimen in paediatric patients and safety data from paediatric patients.

“We continue to be committed to facilitating the development and approval of treatments for rare diseases, particularly those in children,” said Billy Dunn, director of the Division of Neurology Products in the FDA’s Centre for Drug Evaluation and Research. “This approval will provide a much-needed treatment option for paediatric patients with LEMS who have significant weakness and fatigue that can often cause great difficulties with daily activities.”

The FDA has also granted the application Priority Review and Fast Track designations, alongside its Orphan Drug designation, which provides incentives to assist and encourage the development of drugs for rare diseases.

LEMS is a rare autoimmune disorder that affects the connection between nerves and muscles and causes weakness and other symptoms in affected patients. 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.