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FIRDAPSE IS FIRST-LINE TREATMENT FOR ADULTS WITH LEMS1

The only FDA-approved, evidence-based therapy for adults with Lambert-Eaton myasthenic syndrome (LEMS)2,3

A UNIQUE COMPOUND

FIRDAPSE is the only formulation that utilizes amifampridine phosphate, a voltage‑gated potassium channel blocker, to specifically target the presynaptic nerve terminal of neuromuscular junctions.23-25

Molecule Image

Amifampridine phosphate
(3,4-diaminopyridine phosphate)

EXTENSIVELY TESTED

FIRDAPSE has been tested in more than 70 clinical and nonclinical studies, including two positive Phase 3 studies, over a 9-year period.6

In clinical trials, FIRDAPSE demonstrated a rapid onset of action and clinically meaningful improvements in2,26:

  • Muscle strength and maintenance
  • Patient perception of well-being
  • Clinician impression of patient well-being
  • Muscle function and mobility
Molecule Image

Amifampridine phosphate
(3,4-diaminopyridine phosphate)

HELPING LEMS PATIENTS MOVE FORWARD

~3,000
in the US are living with the challenges of LEMS8
600+
have found a path forward with FIRDAPSE6

FIRDAPSE MECHANISM OF ACTION

FIRDAPSE acts at the presynaptic nerve terminal to restore neuromuscular transmission2,23

Illustrated rendering of FIRDAPSE MOA Illustrated rendering of FIRDAPSE MOA
1

In LEMS, autoantibodies block the calcium channels in the nerve cells, reducing ACh release into the neuromuscular junction4,11

2

FIRDAPSE, a voltage-gated potassium channel blocker, specifically targets the presynaptic nerve terminal of the neuromuscular junction2,18

3

FIRDAPSE blocks potassium channels in the nerve cells, which allows more ACh to be released into the neuromuscular junction2,18*

The mechanism by which FIRDAPSE exerts its therapeutic effect in LEMS patients has not been fully elucidated. FIRDAPSE is a broad-spectrum potassium channel blocker.

NEXT: Efficacy
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Indication and 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. Yoon CH, Owusu-Guha J, Smith A, Buschur P. Amifampridine for the management of Lambert-Eaton myasthenic syndrome: a new take on an old drug. Ann Pharmacother. 2020;54(1):56-63.
  2. Full Prescribing Information for FIRDAPSE (amifampridine). Catalyst Pharma; 2018.
  3. Orange Book: Approved drug products with therapeutic equivalence evaluations. US Food and Drug Administration website. https://www.accessdata.fda.gov/scripts/cder/ob/search_product.cfm. Accessed June 10, 2020.
  4. 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.
  5. Skeie GO, Apostolski S, Evoli A, et al. Guidelines for treatment of autoimmune neuromuscular transmission disorders. Eur J Neurol. 2010;17(7):893-902.
  6. Data on file, Catalyst Pharmaceuticals.
  7. Muppidi S, Wolfe GI, Barohn RJ. Diseases of the neuromuscular junction. In: Swaiman K, Ashwal S, Ferriero D, Schor N, eds. Pediatric Neurology: Principles and Practice. 5th ed. Philadelphia, PA: Elsevier; 2011:1549-1569.
  8. Sanders DB. Lambert-Eaton myasthenic syndrome: diagnosis and treatment. Ann NY Acad Sci. 2003;998:500-508.
  9. 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.
  10. 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.
  11. Titulaer MJ, Lang B, Verschuuren JJ. Lambert-Eaton myasthenic syndrome: from clinical characteristics to therapeutic strategies. Lancet Neurol. 2011;10(12):1098-1107.
  12. Titulaer MJ, Wirtz PW, Willems LNA, et al. Screening for small-cell lung cancer: a follow-up study of patients with Lambert-Eaton myasthenic syndrome. J Clin Oncol. 2008;26(26):4276-4281.
  13. Wirtz PW, Smallegange TM, Wintzen AR, Verschuuren JJ. Differences in clinical features between the Lambert-Eaton myasthenic syndrome with and without cancer: an analysis of 227 published cases. Clin Neurol Neurosurg. 2002;104(4):359-363.
  14. Wirtz PW, Wintzen AR, Verschuuren JJ. Lambert-Eaton myasthenic syndrome has a more progressive course in patients with lung cancer. Muscle Nerve. 2005;32(2):226-229.
  15. Maddison P, Lang B, Mill K, Newsom-Davis J. Long term outcome in Lambert-Eaton myasthenic syndrome without lung cancer. J Neurol Neurosurg Psychiatry. 2001;70(2):212-217.
  16. Zalewski NL, Lennon VA, Lachance DH, et al. P/Q- and N-type calcium-channel antibodies: oncological, neurological, and serological accompaniments. Muscle Nerve. 2016;54(2):220-227.
  17. Lennon VA. Serologic profile of myasthenia gravis and distinction from the Lambert-Eaton myasthenic syndrome. Neurology. 1997;48(suppl 5):S23-S27.
  18. Gilhus NE. Lambert-Eaton myasthenic syndrome; pathogenesis, diagnosis, and therapy. Autoimmune Dis. 2011;2011:973808.
  19. Quartel A, Turbeville S, Lounsbury D. Current therapy for Lambert-Eaton myasthenic syndrome: development of 3,4-diaminopyridine phosphate salt as first-line symptomatic treatment. Curr Med Res Opin. 2010;26(6):1363-1375.
  20. Bain PG, Motomura M, Newsom-Davis J, et al. Effects of intravenous immunoglobulin on muscle weakness and calcium-channel autoantibodies in the Lambert-Eaton myasthenic syndrome. Neurology. 1996;47(3):678-683.
  21. Ivanovski T, Miralles F. Lambert-Eaton myasthenic syndrome: early diagnosis is key. Degener Neurol Neuromuscul Dis. 2019;9:27-37.
  22. Wirtz PW, Verschuuren JJ, van Dijk JG, et al. Efficacy of 3,4-diaminopyridine and pyridostigmine in the treatment of Lambert-Eaton myasthenic syndrome: a randomized, double-blind, placebo-controlled, crossover study. Clin Pharmacol Ther. 2009;86(1):44-48.
  23. 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.
  24. Strupp M, Teufel J, Zwergal A, et al. Aminopyridines for the treatment of neurologic disorders. Neurol Clin Pract. 2017;7(1):65-76.
  25. 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.
  26. Shieh P, Sharma K, Korhman B, Oh SJ. Amifampridine phosphate (FIRDAPSE) is effective in a confirmatory phase 3 clinical trial in LEMS. J Clin Neuromuscul Dis. 2019;20(3):111-119.
  27. Jacob S, Muppidi S, Guidon A, et al; International MG/COVID-19 Working Group. Guidance for the management of myasthenia gravis (MG) and Lambert-Eaton myasthenic syndrome (LEMS) during the COVID-19 pandemic. J Neurol Sci. 2020;412:116803.

Indication and 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. Yoon CH, Owusu-Guha J, Smith A, Buschur P. Amifampridine for the management of Lambert-Eaton myasthenic syndrome: a new take on an old drug. Ann Pharmacother. 2020;54(1):56-63.
  2. Full Prescribing Information for FIRDAPSE (amifampridine). Catalyst Pharma; 2018.
  3. Orange Book: Approved drug products with therapeutic equivalence evaluations. US Food and Drug Administration website. https://www.accessdata.fda.gov/scripts/cder/ob/search_product.cfm. Accessed June 10, 2020.
  4. 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.
  5. Skeie GO, Apostolski S, Evoli A, et al. Guidelines for treatment of autoimmune neuromuscular transmission disorders. Eur J Neurol. 2010;17(7):893-902.
  6. Data on file, Catalyst Pharmaceuticals.
  7. Muppidi S, Wolfe GI, Barohn RJ. Diseases of the neuromuscular junction. In: Swaiman K, Ashwal S, Ferriero D, Schor N, eds. Pediatric Neurology: Principles and Practice. 5th ed. Philadelphia, PA: Elsevier; 2011:1549-1569.
  8. Sanders DB. Lambert-Eaton myasthenic syndrome: diagnosis and treatment. Ann NY Acad Sci. 2003;998:500-508.
  9. 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.
  10. 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.
  11. Titulaer MJ, Lang B, Verschuuren JJ. Lambert-Eaton myasthenic syndrome: from clinical characteristics to therapeutic strategies. Lancet Neurol. 2011;10(12):1098-1107.
  12. Titulaer MJ, Wirtz PW, Willems LNA, et al. Screening for small-cell lung cancer: a follow-up study of patients with Lambert-Eaton myasthenic syndrome. J Clin Oncol. 2008;26(26):4276-4281.
  13. Wirtz PW, Smallegange TM, Wintzen AR, Verschuuren JJ. Differences in clinical features between the Lambert-Eaton myasthenic syndrome with and without cancer: an analysis of 227 published cases. Clin Neurol Neurosurg. 2002;104(4):359-363.
  14. Wirtz PW, Wintzen AR, Verschuuren JJ. Lambert-Eaton myasthenic syndrome has a more progressive course in patients with lung cancer. Muscle Nerve. 2005;32(2):226-229.
  15. Maddison P, Lang B, Mill K, Newsom-Davis J. Long term outcome in Lambert-Eaton myasthenic syndrome without lung cancer. J Neurol Neurosurg Psychiatry. 2001;70(2):212-217.
  16. Zalewski NL, Lennon VA, Lachance DH, et al. P/Q- and N-type calcium-channel antibodies: oncological, neurological, and serological accompaniments. Muscle Nerve. 2016;54(2):220-227.
  17. Lennon VA. Serologic profile of myasthenia gravis and distinction from the Lambert-Eaton myasthenic syndrome. Neurology. 1997;48(suppl 5):S23-S27.
  18. Gilhus NE. Lambert-Eaton myasthenic syndrome; pathogenesis, diagnosis, and therapy. Autoimmune Dis. 2011;2011:973808.
  19. Quartel A, Turbeville S, Lounsbury D. Current therapy for Lambert-Eaton myasthenic syndrome: development of 3,4-diaminopyridine phosphate salt as first-line symptomatic treatment. Curr Med Res Opin. 2010;26(6):1363-1375.
  20. Bain PG, Motomura M, Newsom-Davis J, et al. Effects of intravenous immunoglobulin on muscle weakness and calcium-channel autoantibodies in the Lambert-Eaton myasthenic syndrome. Neurology. 1996;47(3):678-683.
  21. Ivanovski T, Miralles F. Lambert-Eaton myasthenic syndrome: early diagnosis is key. Degener Neurol Neuromuscul Dis. 2019;9:27-37.
  22. Wirtz PW, Verschuuren JJ, van Dijk JG, et al. Efficacy of 3,4-diaminopyridine and pyridostigmine in the treatment of Lambert-Eaton myasthenic syndrome: a randomized, double-blind, placebo-controlled, crossover study. Clin Pharmacol Ther. 2009;86(1):44-48.
  23. 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.
  24. Strupp M, Teufel J, Zwergal A, et al. Aminopyridines for the treatment of neurologic disorders. Neurol Clin Pract. 2017;7(1):65-76.
  25. 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.
  26. Shieh P, Sharma K, Korhman B, Oh SJ. Amifampridine phosphate (FIRDAPSE) is effective in a confirmatory phase 3 clinical trial in LEMS. J Clin Neuromuscul Dis. 2019;20(3):111-119.
  27. Jacob S, Muppidi S, Guidon A, et al; International MG/COVID-19 Working Group. Guidance for the management of myasthenia gravis (MG) and Lambert-Eaton myasthenic syndrome (LEMS) during the COVID-19 pandemic. J Neurol Sci. 2020;412:116803.
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