Pharmacokinetics of an immediate-release oral formulation of Fampridine (4-aminopyridine) in normal subjects and patients with spinal cord injury

• Published in: Journal of clinical pharmacology Vol. 43; no. 4; p. 379
• Main Authors: Hayes, K C, Katz, M A, Devane, J G, Hsieh, J T C, Wolfe, D L, Potter, P J, Blight, A R
• Format: Journal Article
• Language: English
• Published: England 01.04.2003
• Subjects: 4-Aminopyridine - administration & dosage; 4-Aminopyridine - adverse effects; 4-Aminopyridine - pharmacokinetics; Administration, Oral; Adult; Area Under Curve; Biological Availability; Chromatography, High Pressure Liquid; Dose-Response Relationship, Drug; Double-Blind Method; Female; Half-Life; Humans; Male; Potassium Channel Blockers - administration & dosage; Potassium Channel Blockers - adverse effects; Potassium Channel Blockers - pharmacokinetics; Spinal Cord Injuries - metabolism; Time Factors
• ISSN: 0091-2700
• DOI: 10.1177/0091270003251388

Plasma concentration profiles of the K+ channel-blocking compound Fampridine were obtained from (1) control subjects (n = 6) following oral administration of doses of 10, 15, 20, and 25 mg and (2) patients with spinal cord injury (SCI) (n = 11) following a single oral dose of 10 mg of an immediate-release formulation. Plasma concentrations were determined using a reversed-phase ion-pair high-performance liquid chromatography (HPLC) assay with ultraviolet light detection employing liquid extraction. The drug was rapidly absorbed with a tmax approximately 1 hour for both groups; tmax was independent of dose. Cmax and AUC0-infinity were linearly related to dose, and t 1/2 was 3 to 4 hours for both groups. There were no obvious differences in the (10-mg) plasma concentration profiles between control subjects and SCI patients. The drug was well tolerated, with only mild and transient side effects of light-headedness, dysesthesias, and dizziness.