Source: DGNews  |  Posted 2 years ago

By Ann Saul

FLORENCE, Italy -- September 23, 2009 -- Fampridine sustained-release (SR) tablets are perceived by patients and clinicians as a beneficial and tolerable long-term therapy, according to results of a study presented at the 13th Congress of the European Federation of Neurological Societies (EFNS).

“Previous studies have shown that the potassium channel blocker fampridine SR improves walking ability in patients with multiple sclerosis [MS],” said Andrew Goodman, MD, University of Rochester, Rochester, New York, speaking here on September 13. “This analysis represents interim data from 2 ongoing, long-term, open-label extension trials designed to examine patient retention.”

The studies, conducted at up to 42 medical centres in the United States and Canada, followed 2 phase 3, double-blind, randomised trials of fampridine SR. The primary endpoint of the parent studies was to determine how many of the patients were Timed Walk Responders (TWR) -- patients whose walking speed was faster than their fastest speed when they were off treatment. All the patients in the extension studies had participated in either of the 2 parent studies. At the clinical cut-off of November 30, 2008, 69.5% (187) of the 269 patients enrolled in MS-F203EXT and 86.0% (184) of the 214 patients enrolled in MS-F204EXT had remained on treatment.

Retention of all patients in MS-F203EXT was 69.5% (187 of 269 patients) and 86.9% (184 of 214 patients) for those in MS-F204EXT. In both extension studies, however, the retention rate was higher among patients who had been TWRs in the original parent studies. In MS-F203EXT, the retention rate was 76% among the TWRs, compared with 65% of the non-TWRs and 71% of the placebo patients. In MS-F204EXT, retention rate of patients who were TWRs was 89%, compared to 82% for non-TWRs and 86% for placebo patients.

The total number of patients reporting a treatment-emergent adverse event was 97.4% (262) in MS-F203EXT and 88.8% (190) in MS-F204EXT. Serious adverse events, most commonly MS relapse, were reported in 23.4% of patients in MS-F203EXT and in 7.9% of patients in MS-F204EXT.

In MS-F203EXT, 4 patients had seizure-related events, but there were no patients with seizure in MS-F204EXT.

“Patients and clinicians seem to be working together to determine the level of risk for adverse events that they are willing to take for the benefits of fampridine-SR,” said Dr. Goodman. “Even though their participation is voluntary, the retention rate is high, suggesting that this is seen as a beneficial and tolerable long-term therapy.”

While the highest rates of retention were among patients who consistently improved in walking speed during the parent studies, there was also substantial patient retention even among those whose walking speed had not improved.

Funding for this study was provided by Acorda Therapeutics Inc.

Presentation title: Patient Retention in Long-Term Extension Studies of Fampridine Sustained Release Tablets (Fampridine-SR) in Patients With Multiple Sclerosis. Poster 1622