Drug updated on 3/28/2024
| Dosage Form | Tablet (oral; 10 mg) |
| Drug Class | Potassium channel blockers |
| Ongoing and Completed Studies | ClinicalTrials.gov |
Indication
- Indicated for the treatment of Lambert-Eaton myasthenic syndrome (LEMS) in adults and pediatric patients 6 years of age and older.
Summary
- Amifampridine (Firdapse) is indicated for the treatment of Lambert-Eaton myasthenic syndrome (LEMS) in adults and pediatric patients 6 years of age and older.
- A total of three systematic reviews/meta-analyses were reviewed to gather information about this drug's efficacy and safety profile.
- The first review reveals that a meta-analysis involving six randomized controlled trials with 115 LEMS patients showed significant improvement after treatment with amifampridine, as evidenced by decreased quantitative myasthenia gravis scores and increased compound muscle action potentials amplitude.
- According to the second review, two phase III clinical trials have confirmed the superiority of amifampridine over placebo in managing LEMS symptoms, demonstrating its effectiveness while maintaining minimal adverse effects; it also suggests that due to improved stability profile and reduced dose variability, amifampridine may become first-line management for LEMS.
- The third document provides an expert opinion stating that amifampridines are safe, tolerable, effective symptomatic medication for LEMS; they can be supplemented with pyridostigmine for long-term use without any undue side-effects if daily dosage remains under 80 mg per day.
- Common side effects include peri-oral paresthesia which many patients accept as a sign of drug intake according to the same expert review; gastrointestinal reactions are reported but considered tolerable by most users making it generally well-tolerated among patient population suffering from LEMS crisis or requiring long term usage.
Product Monograph / Prescribing Information
| Document Title | Year | Source |
|---|---|---|
| Firdapse (amifampridine) Prescribing Information. | 2023 | Catalyst Pharmaceuticals, Coral Gables, FL |
Systematic Reviews / Meta-Analyses
| Document Title | Year | Source |
|---|---|---|
| Combined clinical and pharmacoeconomic report for amifampridine phosphate (Firdapse). | 2022 | CADTH |
| 3,4-diaminopyridine treatment for Lambert-Eaton myasthenic syndrome in adults: a meta-analysis of randomized controlled trials. | 2021 | BMC Neurology |
| Amifampridine for the Management of Lambert-Eaton Myasthenic Syndrome: A New Take on an Old Drug. | 2020 | Annals of Pharmacotherapy |
| Amifampridine for the treatment of Lambert-Eaton myasthenic syndrome. | 2019 | Expert Review of Clinical Immunology |