Background Mobility impairment is a common disability in multiple sclerosis (MS) and negatively impacts patients’ lives. Clinical studies suggest that fampridine improves motor function in people with MS.

Purpose To assess the effectiveness and security of sustained release fampridine in patient with MS and walking disability (EDSS 4–7) after 2 weeks of treatment.

Material and methods A 1 year prospective observational study was performed (July 2014–July 2015). Patient characteristics (age, sex and different MS subtypes), fampridine dose information, associated disease modifying treatments and baseline EDSS were collected from the available hospital databases. The timed 25 foot walk test (T25FW) and the 12 item Multiple Sclerosis Walking Scale (MSWS-12) were performed before the start of treatment with fampridine and after 2 weeks to define response. The primary outcome measures were mean changes in walking speed (T25FW). Improvement of >20% was indicated as a clinically meaningful change. Reported adverse events were also collected during this period. Bootstrapping for paired samples was calculated for effectiveness variables, assuming a p value <0.05.

Results 34 patients were treated, all with 10 mg twice daily; 55.88% were women. Mean age was 50.76 years (95% CI 46.90 to 54.63). 21 patients (61.77%) had progressive subtypes and 13 (38.23%) relapsing remitting MS. 33 patients (97.07%) had an EDSS between 6 and 7. Associated disease modifying treatments were: 11 none (32.35%), 8 fingolimod (23.53%), 6 interferon beta 1A (17.65%), 4 natalizumab (11.76%), 3 interferon beta 1B (8.8%) and 2 glatiramer (5.88%). The mean time reduction in T25FW was 5.81 s (95% CI 2.58 to 9.17, p = 0.007) and walking speed increased by 30.02% (95% CI 22.31 to 37.74). The MSWS-12 mean decrease over 100 was 21.53 points (95% CI15.00 to 28.0.4, p = 0.001). Fampridine was withdrawn in 6 patients (17.65%); 3 of them were considered non-responders and the rest suffered arrhythmia as an adverse event.

 Conclusion Treatment with fampridine focused on patients with an advanced stage of progressive subtypes of MS with either no other associated disease modifying treatments or secondline associated treatments, such as fingolimod and natalizumab. Treatment resulted in clinically meaningful improvements in walking speed. Arrhythmia was the only adverse event reported.

References and/or Acknowledgements We thank the hospital pharmacists at Torrecardenas for their support.

No conflict of interest.