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About LEMS

The disorder is rare; the impact is real

WHAT IS LAMBERT-EATON MYASTHENIC SYNDROME (LEMS)?

LEMS is a rare autoimmune neuromuscular disorder estimated to affect 1 in 100,000 people in the United States—of these, many are undiagnosed or misdiagnosed.4,5

WHAT ARE THE SYMPTOMS?

LEMS results in progressive, debilitating muscle weakness and fatigue. The disorder is characterized by diminished physical functionality and impairments in activities of daily living (ADL).4,6-8

WHAT CAUSES LEMS?

LEMS is caused by autoantibodies to presynaptic P/Q‑type voltage‑gated calcium channels (VGCCs) that effectively decrease acetylcholine (ACh) release and inhibit neuromuscular transmission.1,9

Man In Seat

PROGRESSION OF LEMS SYMPTOMS CONTRIBUTES TO WORSENING DISEASE BURDEN4,6-8

In a 2012 survey of patients living with LEMS8:

  • 75% reported partial or total restriction of ADL, such as rising from a chair or climbing stairs
  • More than half (58.3%) were hospitalized prior to diagnosis, while nearly all (91.7%) were hospitalized post‑diagnosis
  • More than 50% reported severe leg weakness, dry mouth, and difficulty focusing their sight
In severe cases, people with LEMS can require round-the-clock caregiver support, which may create a financial and emotional burden on families.

THE LONG, ARDUOUS JOURNEY TO A LEMS DIAGNOSIS

In a 2012 cross‑sectional study, the mean time between a patient’s first visit to a physician and a confirmed diagnosis of LEMS was 4.4 years8

REASONS FOR DELAY

  • Nonspecific and fluctuating symptoms5
  • Slow progression of disease5
  • Overlapping signs with other paraneoplastic syndromes6

MISDIAGNOSIS IS COMMON

LEMS clinical presentation often resembles other more common disorders, such as5,6:

  • Myasthenia gravis
  • Guillain‑Barré syndrome
  • Amyotrophic lateral sclerosis
  • Other neurological disorders, such as Parkinson’s disease, multiple sclerosis, or fibromyalgia
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Indication & Important Safety Information

indications and usage:

FIRDAPSE is a potassium channel blocker indicated for the treatment of Lambert-Eaton myasthenic syndrome (LEMS) in adults.

CONTRAINDICATIONS

FIRDAPSE is contraindicated in patients with:

  • A history of seizures
  • Hypersensitivity to amifampridine phosphate or another aminopyridine

WARNINGS AND PRECAUTIONS

Seizures: FIRDAPSE can cause seizures. Consider discontinuation or dose-reduction of FIRDAPSE in patients who have a seizure while on treatment. FIRDAPSE is contraindicated in patients with a history of seizures.

Hypersensitivity: If a hypersensitivity reaction such as anaphylaxis occurs, FIRDAPSE should be discontinued and appropriate therapy initiated.

ADVERSE REACTIONS

The most common (> 10%) adverse reactions are: paresthesia, upper respiratory tract infection, abdominal pain, nausea, diarrhea, headache, elevated liver enzymes, back pain, hypertension, and muscle spasms.

To report SUSPECTED ADVERSE REACTIONS, contact Catalyst Pharmaceuticals at 1-844-347-3277 (1-844-FIRDAPSE) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

References:
  1. Lennon VA, Kryzer TJ, Griesmann GE, et al. Calcium-channel antibodies in the Lambert-Eaton syndrome and other paraneoplastic syndromes. N Engl J Med. 1995;332(22):1467-1474.
  2. Skeie GO, Apostolski S, Evoli A, et al. Guidelines for treatment of autoimmune neuromuscular transmission disorders. Eur J Neurol. 2010;17(7):893-902.
  3. Data on file, Catalyst Pharmaceuticals.
  4. Sanders DB. Lambert-Eaton myasthenic syndrome: diagnosis and treatment. Ann NY Acad Sci. 2003;998:500-508
  5. Titulaer MJ, Lang B, Verschuuren JJ. Lambert-Eaton myasthenic syndrome: from clinical characteristics to therapeutic strategies. Lancet Neurol. 2011;10(12):1098-1107.
  6. Merino-Ramírez MÁ, Bolton CF. Review of the diagnostic challenges of Lambert-Eaton syndrome revealed through three case reports. Can J Neurol Sci. 2016;43(5):635-647.
  7. Mantegazza R, Meisel A, Sieb JP, et al. The European LEMS Registry: baseline demographics and treatment approaches. Neurol Ther. 2015;4(2):105-124.
  8. Harms L, Sieb JP, Williams AE, et al. Long-term disease history, clinical symptoms, health status, and healthcare utilization in patients suffering from Lambert Eaton myasthenic syndrome: results of a patient interview survey in Germany. J Med Econ. 2012;15(3):521-530.
  9. Motomura M, Lang B, Johnston I, Palace J, Vincent A, Newsom-Davis J. Incidence of serum anti-P/Q-type and anti-N-type calcium channel autoantibodies in the Lambert-Eaton myasthenic syndrome. J Neurol Sci. 1997;147(1):35-42.
  10. Oh SJ, Sieb JP. Update on amifampridine as a drug of choice in Lambert-Eaton myasthenic syndrome. US J Neurol. 2014;10(2):83-89.
  11. Strupp M, Teufel J, Zwergal A, et al. Aminopyridines for the treatment of neurologic disorders. Neurol Clin Pract. 2017;7(1):65-76.
  12. Lindquist S, Stangel M. Update on treatment options for Lambert-Eaton myasthenic syndrome: focus on use of amifampridine. Neuropsychiatr Dis Treat. 2011;7:341-349.
  13. Full Prescribing Information for FIRDAPSE (amifampridine). Catalyst Pharma; 2018.
  14. Oh SJ, Shcherbakova N, Kostera-Pruszczyk A, et al; LEMS Study Group. Amifampridine phosphate (FIRDAPSE®) is effective and safe in a phase 3 clinical trial in LEMS. Muscle Nerve. 2016;53(5):717-725.

Indication & Important Safety Information

indications and usage:

FIRDAPSE is a potassium channel blocker indicated for the treatment of Lambert-Eaton myasthenic syndrome (LEMS) in adults.

CONTRAINDICATIONS

FIRDAPSE is contraindicated in patients with:

  • A history of seizures
  • Hypersensitivity to amifampridine phosphate or another aminopyridine

WARNINGS AND PRECAUTIONS

Seizures: FIRDAPSE can cause seizures. Consider discontinuation or dose-reduction of FIRDAPSE in patients who have a seizure while on treatment. FIRDAPSE is contraindicated in patients with a history of seizures.

Hypersensitivity: If a hypersensitivity reaction such as anaphylaxis occurs, FIRDAPSE should be discontinued and appropriate therapy initiated.

ADVERSE REACTIONS

The most common (> 10%) adverse reactions are: paresthesia, upper respiratory tract infection, abdominal pain, nausea, diarrhea, headache, elevated liver enzymes, back pain, hypertension, and muscle spasms.

To report SUSPECTED ADVERSE REACTIONS, contact Catalyst Pharmaceuticals at 1-844-347-3277 (1-844-FIRDAPSE) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

References:
  1. Lennon VA, Kryzer TJ, Griesmann GE, et al. Calcium-channel antibodies in the Lambert-Eaton syndrome and other paraneoplastic syndromes. N Engl J Med. 1995;332(22):1467-1474.
  2. Skeie GO, Apostolski S, Evoli A, et al. Guidelines for treatment of autoimmune neuromuscular transmission disorders. Eur J Neurol. 2010;17(7):893-902.
  3. Data on file, Catalyst Pharmaceuticals.
  4. Sanders DB. Lambert-Eaton myasthenic syndrome: diagnosis and treatment. Ann NY Acad Sci. 2003;998:500-508
  5. Titulaer MJ, Lang B, Verschuuren JJ. Lambert-Eaton myasthenic syndrome: from clinical characteristics to therapeutic strategies. Lancet Neurol. 2011;10(12):1098-1107.
  6. Merino-Ramírez MÁ, Bolton CF. Review of the diagnostic challenges of Lambert-Eaton syndrome revealed through three case reports. Can J Neurol Sci. 2016;43(5):635-647.
  7. Mantegazza R, Meisel A, Sieb JP, et al. The European LEMS Registry: baseline demographics and treatment approaches. Neurol Ther. 2015;4(2):105-124.
  8. Harms L, Sieb JP, Williams AE, et al. Long-term disease history, clinical symptoms, health status, and healthcare utilization in patients suffering from Lambert Eaton myasthenic syndrome: results of a patient interview survey in Germany. J Med Econ. 2012;15(3):521-530.
  9. Motomura M, Lang B, Johnston I, Palace J, Vincent A, Newsom-Davis J. Incidence of serum anti-P/Q-type and anti-N-type calcium channel autoantibodies in the Lambert-Eaton myasthenic syndrome. J Neurol Sci. 1997;147(1):35-42.
  10. Oh SJ, Sieb JP. Update on amifampridine as a drug of choice in Lambert-Eaton myasthenic syndrome. US J Neurol. 2014;10(2):83-89.
  11. Strupp M, Teufel J, Zwergal A, et al. Aminopyridines for the treatment of neurologic disorders. Neurol Clin Pract. 2017;7(1):65-76.
  12. Lindquist S, Stangel M. Update on treatment options for Lambert-Eaton myasthenic syndrome: focus on use of amifampridine. Neuropsychiatr Dis Treat. 2011;7:341-349.
  13. Full Prescribing Information for FIRDAPSE (amifampridine). Catalyst Pharma; 2018.
  14. Oh SJ, Shcherbakova N, Kostera-Pruszczyk A, et al; LEMS Study Group. Amifampridine phosphate (FIRDAPSE®) is effective and safe in a phase 3 clinical trial in LEMS. Muscle Nerve. 2016;53(5):717-725.