Safety and Tolerability | FIRDAPSE® (amifampridine)

Clinical studies have shown that FIRDAPSE is well tolerated. Most of the reported adverse events during these studies were mild to moderate^3,4

ADVERSE REACTIONS IN ≥5% OF PATIENTS WITH LEMS NEWLY TREATED WITH FIRDAPSE²

Table illustrating that clinical studies have shown FIRDAPSE is well tolerated. Most of the reported adverse events during these studies were mild to moderate. Adverse
reactions in greater than or equal to 5% of patients with LEMS newly treated with FIRDAPSE include paresthesia (62%), upper respiratory tract infection (33%), abdominal pain (14%), nausea (14%), diarrhea (14%),
headache (14%), elevated liver enzymes (14%), back pain (14%), hypertension (12%), muscle spasms (12%), dizziness (10%), asthenia (10%), muscular weakness (10%),
pain in extremity (10%), cataract (10%), constipation (7%), bronchitis (7%), fall (7%), and lymphadenopathy (7%)

*Includes paresthesia, oral paresthesia, and oral hypoesthesia.³ †Includes elevated alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and gamma-glutamyl transferase (GGT).

During LMS 002 (Study 1), the majority of adult patients (62%) with no prior exposure to amifampridine experienced transient paresthesia while taking FIRDAPSE. Most instances diminished during the course of the study.^2,28

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

Do you have a patient taking FIRDAPSE who is pregnant?

FIRDAPSE Pregnancy Registry icon

The FIRDAPSE Pregnancy Registry: In conjunction with the FDA, Catalyst Pharmaceuticals has created a registry to collect information about the safety of FIRDAPSE use during pregnancy. Enroll patients with LEMS—even those not taking FIRDAPSE—as soon as you learn of their pregnancy by calling 1-855-212-5856 or visiting www.firdapsepregnancystudy.com.

NEXT: FIRDAPSE Dosing

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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.

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