Lambert Eaton Myasthenic Syndrome (LEMS) Antibody Testing and Treatment Recommendations Added to NCCN Clinical Practice Guidelines for Small Cell Lung Cancer (SCLC)

Core Insights - Catalyst Pharmaceuticals announced that the National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines for Small Cell Lung Cancer (SCLC) now include new recommendations regarding Lambert Eaton myasthenic syndrome (LEMS) and the use of amifampridine (FIRDAPSE) [1][2] Group 1: NCCN Guidelines Update - The updated NCCN guidelines for SCLC now specify symptoms of LEMS, including proximal muscle weakness and autonomic dysfunction, and recommend diagnosis through neurological evaluation and testing for PQ- and N-type VGCC antibodies [2] - Amifampridine is recommended as a treatment option in consultation with neurology under the principles of supportive care [2] Group 2: LEMS and SCLC Connection - Approximately 50% of LEMS cases are associated with an underlying malignancy, most commonly SCLC, with literature indicating that LEMS is observed in 3% of SCLC patients [3] - An internal healthcare database analysis suggests that potentially 90% of LEMS patients with SCLC remain undiagnosed, which may lead to untreated symptoms during SCLC treatment [3] Group 3: Importance of Early Diagnosis - Early diagnosis of LEMS in SCLC is critical for improving patient outcomes, as effective treatment of LEMS symptoms can enhance the overall management of SCLC [4] - Accurate identification through VGCC antibody testing and comprehensive neurological evaluation is emphasized as essential for patient care [4] Group 4: Company Overview - Catalyst Pharmaceuticals is focused on improving the lives of patients with rare diseases and has a proven track record in bringing life-changing treatments to market [5] - The company prioritizes accessibility and support services to ensure patients receive necessary care, maintaining a strong U.S. presence while exploring global expansion opportunities [5] - Catalyst was recognized on the Forbes 2025 list as one of America's Most Successful Mid-Cap Companies and on the 2024 Deloitte Technology Fast 500™ list as one of North America's Fastest-Growing Companies [5]