First pediatric LEMS option approved, disrupting market

The US regulator has granted privately-held Jacobus Pharmaceutical approval for its rare disease therapy Ruzurgi (amifampridine), to treat children with Lambert-Eaton myasthenic syndrome (LEMS).

The decision marks the first US Food and Drug Administration approval of a treatment specifically for children with LEMS, a rare autoimmune disorder that affects the connection between nerves and muscles, causing weakness and other symptoms.

The approval caused shares in Catalyst Pharmaceuticals (Nasdaq: CPRX) to crater in morning trading, down almost 40%.