Open Label Extension Study to Evaluate the Safety and Tolerability of Oral Fampridine-Sustained Release (SR) in Canadian Participants With Multiple Sclerosis Who Participated in Acorda Extension Trials.

Key Inclusion Criteria :

• Previously enrolled in 1 of the 3 Acorda-sponsored studies (MS-F202EXT, MS-F203EXT, and MS-F204EXT) and continuing to receive fampridine-SR.
• Willing to comply with the required scheduling and assessments of the protocol.
• Female subjects of childbearing potential, regardless of sexual activity, must have a negative urine pregnancy test, and must practice effective contraception during the study and be willing and able to continue contraception for 1 month after their last dose of study treatment.

Key Exclusion Criteria:

• Discontinued prematurely from the preceding study ((MS-F202EXT, MS-F203EXT, or MS-F204EXT).
• Any prior history of seizure, epilepsy, or other convulsive disorder.
• Any clinically significant abnormal laboratory values.
• New history of moderate or severe renal impairment.
• New history of angina, uncontrolled hypertension, clinically significant cardiac arrhythmias, or any other clinically significant cardiovascular abnormality, as judged by the Investigator.
• Any significant change in overall health that would preclude subject's participation in the study, in the opinion of the Investigator.
• Known allergy to pyridine-containing substances or any of the inactive ingredients of the fampridine-SR tablet
• Received an investigational drug, except fampridine-SR under the preceding study (MS-F202EXT, MS-F203EXT, or MS-F204EXT), within the last 30 days, or the subject is scheduled to enroll in an investigational drug at any time during the study.
• A history of drug or alcohol abuse within the past year.
• Treatment with other forms of fampridine or 4-AP (e.g., compounded formulation of 4-AP) or 3,4-diaminopyridine (3,4-DAP).

NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.