Pediatric Dosing | FIRDAPSE® (amifampridine)

Dosing for pediatric patients ≥6 years of age²*^†

FIRDAPSE Pediatric Dosing Table

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Review general FIRDAPSE dosing information here.

* In patients with renal or hepatic impairment and individuals known to be poor metabolizers of N-acetyltransferase 2 (NAT2), the starting dosage of FIRDAPSE should be the lowest recommended dose taken orally in divided doses. This dose should continue to be titrated to clinical effect and tolerability.² † Safety of FIRDAPSE was evaluated in pediatric patients in an expanded access program in which 21 pediatric patients received FIRDAPSE for at least 1 year. Adverse reactions reported in pediatric patients were similar to those seen in adult patients, with the exception of clinically significant weight loss in two pediatric patients at doses of 60 mg per day and higher.²

Help your patients reach their optimal therapeutic dose

Titration is an important step for new patients who are just getting started on FIRDAPSE and have not taken amifampridine before. By guiding your patients through the titration process, you can help:

Determine their optimal therapeutic dose of FIRDAPSE
Maximize neuromuscular benefit
Minimize issues with tolerability, including paresthesia

FOR FIRDAPSE PATIENTS WITH SPECIAL DOSING OR ADMINISTRATION NEEDS

A suspension can be prepared for patients who: have dosing adjustments <5 mg, have trouble swallowing tablets, or require a feeding tube. Please refer to the Medication Guide.

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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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