Fampridine Prolonged Release: A Review in Multiple Sclerosis Patients with Walking Disability

The incidence and prevalence, diagnosis, and treatment of multiple sclerosis in China: a narrative review

In 2018, the first list of rare diseases was published by the National Health Council of China, and multiple sclerosis (MS) was included in this list. Since then, the Chinese government and neurologists have made efforts to improve the clinical outcomes of patients with MS. During last few years, the incidence of MS in China was also investigated. The early and accurate diagnosis of MS was improved due to the application and promotion of magnetic resonance imaging and new diagnosis criteria. The market for and medical insurance access to disease-modifying therapies (DMTs) has been greatly accelerated, which has provided more treatment options and improved clinical outcomes for patients with MS, as well as reduced treatment cost. The pattern of MS in China is gradually changing, from delayed to early diagnosis, and from no treatment to treatment with DMTs during remission. This narrative review aimed to summarize an update to the status of MS in China, including incidence and prevalence, diagnosis, and available treatments. This would help to better understand the diagnosis and treatment gap between mainland China and other Asian regions, demonstrating the necessity of accurate diagnosis and optimized treatment of MS in China.

Fampridine-induced changes in walking kinetics are associated with clinical improvements in patients with multiple sclerosis

Gait dysfunction is common in patients with multiple sclerosis (PwMS). Treatment with prolonged-release fampridine (PR-fampridine) improves walking ability in some PwMS. Associated fampridine-induced changes in the walking pattern are still poorly understood but may provide a better understanding of the mechanisms underlying the beneficial drug effects. 61 PwMS were treated with PR-fampridine in a randomized, monocentric, double-blind and placebo-controlled clinical trial with crossover design (FAMPKIN). Drug-induced improvements in walking speed (Timed-25-Foot Walk; T25FW) and endurance (6-Minute Walk Test; 6MWT) were quantified. In this sub-study of the FAMPKIN trial, fampridine-induced changes in kinetic gait patterns were analyzed by pressure-based foot print analysis during treadmill walking. Vertical ground reaction forces were analyzed during different gait phases. Kinetic data of 44 PwMS was eligible for analysis. During double-blind treatment with PR-fampridine, patients performed significantly better in the T25FW and 6MWT than during placebo treatment (p < 0.0001 for both). At the group level (n = 44), there were no significant changes of gait kinetics under PR-fampridine vs. placebo. However, we found relevant changes of walking kinetics regarding forces during loading, single limb and pre-swing phase in a patient sub-group (n = 8). Interestingly, this sub-group demonstrated superior responsiveness to PR-fampridine in the clinical walking tests compared to those patients without any fampridine-induced changes in kinetics (n = 36). Our results demonstrate fampridine-induced changes in gait kinetics in a sub-group of PwMS. These gait pattern changes were accompanied by improved clinical walking performance under PR-fampridine. These results shed some light on the biomechanical changes in walking patterns underlying enhanced fampridine-induced gait performance.

Exome sequencing in multiple sclerosis families identifies 12 candidate genes and nominates biological pathways for the genesis of disease

Multiple sclerosis (MS) is an inflammatory disease of the central nervous system characterized by myelin loss and neuronal dysfunction. Although the majority of patients do not present familial aggregation, Mendelian forms have been described. We performed whole-exome sequencing analysis in 132 patients from 34 multi-incident families, which nominated likely pathogenic variants for MS in 12 genes of the innate immune system that regulate the transcription and activation of inflammatory mediators. Rare missense or nonsense variants were identified in genes of the fibrinolysis and complement pathways (PLAU, MASP1, C2), inflammasome assembly (NLRP12), Wnt signaling (UBR2, CTNNA3, NFATC2, RNF213), nuclear receptor complexes (NCOA3), and cation channels and exchangers (KCNG4, SLC24A6, SLC8B1). These genes suggest a disruption of interconnected immunological and pro-inflammatory pathways as the initial event in the pathophysiology of familial MS, and provide the molecular and biological rationale for the chronic inflammation, demyelination and neurodegeneration observed in MS patients.

Long-term effects of prolonged-release fampridine in cognitive function, fatigue, mood and quality of life of MS patients: The IGNITE study

BACKGROUND

Studies have reported conflicting results regarding the potential benefit of prolonged release (PR) fampridine in other domains besides walking. Moreover, only a small number of studies have explored long- term effects of PR fampridine. The aim of this study was to assess cognitive function, quality of life, mood and fatigue in MS patients treated with fampridine after 6 and 12 months of treatment.

METHODS

IGNITE was an observational, open label study. Subjects were examined with the timed 25-ft walk (T25FW) and the BICAMS battery and were asked to complete the Multiple Sclerosis Impact Scale (MSIS-29), Modified Fatigue Impact Scale (MFIS), Beck Depression Inventory-II (BDI-II) and MS International Quality-of-Life questionnaire (MUSIQOL) at baseline and at weeks 24 and 48. Patients were sub-grouped into responders (n:40) and non-responders (n:20) according to T25FW performance after 2 weeks on treatment.

RESULTS

After 6 months, statistically significant improvement was observed on T25FW (p < .001), SDMT (p < .001) and MSIS29 (p < .001), for responders. After 1 year on treatment, statistically significant improvement was observed in T25FW (p < .001), MSIS29 (p = .004), SDMT (p < .001) and MUSIQOL (p = .03) for responders. There were no statistically significant improvements for the non-responders.

CONCLUSIONS

PR Fampridine may have a beneficial effect on information processing speed though not on memory. Study data provide some evidence that fampridine treatment may reduce the impact of MS on daily activities and improve quality of life but has no effect on subjective fatigue and mood.