What are the indications for dalfampridine (multiple sclerosis treatment)?

Indications for Dalfampridine in Multiple Sclerosis

Dalfampridine is indicated as a treatment to improve walking in adult patients with multiple sclerosis (MS), demonstrated by an increase in walking speed. 1

Mechanism of Action

• Dalfampridine (also known as fampridine or 4-aminopyridine) is a potassium channel blocker that works by restoring axonal conduction through blockade of potassium channels that become exposed during axonal demyelination 2
• This mechanism helps improve nerve signal transmission in damaged nerve pathways, addressing walking impairment which is a clinical hallmark of MS 2

Clinical Evidence Supporting Use

• FDA approval was based on two pivotal Phase III clinical trials that demonstrated significant improvement in walking speed compared to placebo 3
• In these trials, a significantly higher proportion of patients responded to dalfampridine (35-42.9%) compared to placebo (8-9.3%) with improvements in walking speed of approximately 25% 4, 3
• Long-term extension studies showed sustained improvements in walking speed for up to 2.5 years of continuous treatment 4

Dosing Recommendations

• The recommended dose is 10 mg taken orally twice daily (approximately 12 hours apart) 3, 5
• Higher doses are associated with an increased risk of seizures and should be avoided 3
• The medication has a narrow therapeutic window, making adherence to the prescribed dosing regimen essential 6

Important Contraindications

• History of seizures (absolute contraindication) 2, 6
• Moderate to severe renal impairment 5
• The risk of seizures appears to be dose-related, with low incidence at the recommended 10 mg twice daily dosing 6

Patient Selection Considerations

• Dalfampridine is appropriate for adult MS patients with walking impairment regardless of MS classification 5
• The medication has a quick onset of action, allowing rapid determination of therapeutic response 6
• Treatment should be continued only in patients who demonstrate an adequate response (improved walking speed) 3
• Electroencephalography (EEG) screening is not required before initiating treatment in patients without contraindications 6

Common Adverse Effects

• Most frequently reported adverse events include insomnia, dizziness, headache, nausea, and weakness 5
• At the approved dose of 10 mg twice daily, the seizure risk does not appear to be elevated relative to the baseline risk in the MS population 6

Clinical Monitoring

• Patients should be monitored for improvement in walking speed to determine treatment efficacy 3
• Strict adherence to the prescribed dosing regimen should be emphasized to minimize seizure risk 6
• Patients should be monitored for adverse events, particularly those affecting the central nervous system 5