Diagnostic Test | FIRDAPSE® (amifampridine)

COMPLIMENTARY DIAGNOSTIC TESTING FOR LAMBERT-EATON MYASTHENIC SYNDROME (LEMS)

Catalyst Pharmaceuticals, in collaboration with a national diagnostic lab provider, offers no-cost anti-VGCC antibody testing for patients who have symptoms suggestive of LEMS.

The test is available to providers who have patients with:

A clinical suspicion of LEMS
A negative AChR antibody test despite MG-like symptoms
An equivocal repetitive nerve stimulation test for LEMS

DISCOVER A DIFFERENTIAL DIAGNOSIS OF LEMS

Misdiagnosis is common with LEMS—studies suggest that more than half of patients with LEMS receive an initial misdiagnosis.¹² Fortunately, testing for the presence of anti-VGCC antibodies can confirm diagnosis.

Anti-VGCC antibodies are found in 85%-90% of patients with LEMS12

Don’t let another day go by

LEMS is a progressive disorder, and its debilitating symptoms can worsen over time.⁵ Fortunately, treatment with FIRDAPSE^® (amifampridine) can help patients maintain muscle strength and mobility.^2,4

HELP YOUR PATIENTS TAKE A DEFINITIVE STEP FORWARD

Get the test request form by calling 1-833-422-8259 or contacting a Catalyst Representative below.

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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 and pediatric patients 6 years of age and older.

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.

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.

Please see full Prescribing Information for additional Important Safety Information.

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:

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Full Prescribing Information for FIRDAPSE (amifampridine). Catalyst Pharma; 2023.
Oh SJ, Scherbakova 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.
Shieh P, Sharma K, Kohrman 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.
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Data on file, Catalyst Pharmaceuticals.
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