Assessing the long-term clinical benefit of prolonged-release fampridine tablets in a real-world setting: a review of 67 cases
Patient #3 was a 39-year-old white woman with a 26-year history of MS and secondary-progressive MS for the past 9 years. She had previously received intramuscular interferon β-1a, intravenous immunoglobulin, baclofen for spasticity, steroids, and rehabilitation therapy, but had not been treated with compounded 4-AP. Patient #3 reported fatigue; heat intolerance; cerebellar symptoms; vertigo; imbalance; loss of vision associated with nystagmus; and pain, parathesias, loss of sensation, weakness, spasticity, and muscle tightness in her legs. The patient had sensory impairment, imbalance, limitations in leg muscle strength, and bilateral visual impairment that together contributed to a severe walking impairment and made it difficult for her to walk a great distance. She reported that she could walk a maximum of 20 m using two walking crutches. The patient was currently receiving rehabilitation therapy but not disease-modifying therapy for MS or drugs for spasticity. Clinical assessment revealed that she had severe walking impairment due to spastic paraparesis and ataxia (see ), an EDSS score of 6.5, severe spasticity in both legs, proximal and distal paraparesis (LEMMT grades 4 out of 5 and 2 out of 5, respectively), and a T25FW time of 29.4 seconds (walking speed, 0.26 m/second).\nAfter 4 weeks of treatment with PR-fampridine, patient #3 reported experiencing dizziness, confusion, and difficulties with short-term memory tasks after initiating PR-fampridine. She had a slower walking speed on the T25FW (decrease of 46.2%), no change on the MSWS-12, and worse fatigue and overall health status ( and see ). She continued to have severe spasticity in both legs, and her paraparesis remained unchanged proximally but worsened distally (LEMMT grade 1 out of 5). Interestingly, this patient did report an improvement in her vision and physician assessment at the 4-week visit found no detectable nystagmus. Based on physician assessment and patient report, this patient was considered to have no clinical benefit with PR-fampridine treatment and she reported potentially treatment-related side effects. Treatment with PR-fampridine was stopped and the patient was no longer followed-up on.