FIRDAPSE IS THE RECOMMENDED FIRST-LINE TREATMENT FOR LAMBERT-EATON MYASTHENIC SYNDROME (LEMS)1

The only FDA-approved LEMS treatment for adults and pediatric patients 6 years of age and older1,2

A UNIQUE COMPOUND

FIRDAPSE was the first FDA-approved therapy containing amifampridine, a voltage-gated potassium channel blocker that targets the presynaptic nerve terminal of neuromuscular junctions.28-30*

Chemical structure of FIRDAPSE compound
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.2,31

In clinical trials, FIRDAPSE demonstrated clinically meaningful preservation in muscle strength and patient satisfaction2-4:

Chemical structure of FIRDAPSE compound
Amifampridine phosphate
(3,4-diaminopyridine phosphate)

CHANGING LIVES

~3,000 people in the US are living with the challenges of LEMS

people in the US are living with the challenges of LEMS11

>1000 people have put their lives back in motion with FIRDAPSE

people have put their lives back in motion with FIRDAPSE31

*The mechanism by which FIRDAPSE exerts its therapeutic effect in patients with LEMS has not been fully elucidated.
FIRDAPSE is a broad-spectrum potassium channel blocker.2

FIRDAPSE MECHANISM OF ACTION

FIRDAPSE acts at the presynaptic nerve terminal to restore neuromuscular transmission2,28*

In a patient with LEMS, Immunoglobulin G (IgG) autoantibodies bind to voltage-gated calcium channels (VGCCs) on the presynaptic membrane, thereby reducing ACh release into the neuromuscular junction17-19

Presynaptic potassium channels—which help regulate neuromuscular transmission—are blocked by FIRDAPSE, resulting in prolonged repolarization of the presynaptic membrane32,33*

A prolonged presynaptic action potential allows an increased influx of calcium, which in turn triggers increased ACh release34,35

ACh then binds to AChR receptors on the muscle, initiating a sequence of events that results in muscle contraction36

*The mechanism by which FIRDAPSE exerts its therapeutic effect in patients with LEMS has not been fully elucidated. FIRDAPSE is a broad-spectrum potassium channel blocker.2
NEXT: Efficacy

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