Monitoring long-term efficacy of fampridine in gait-impaired patients with multiple sclerosis

Fampridine in multiple sclerosis patients with acute phase of cervical transverse myelitis: a double-blind, randomized placebo-controlled trial

BACKGROUND

Fampridine is a potassium channel blocker drug used to improve walking ability in patients with multiple sclerosis (MS). We evaluated the effect of fampridine in patients with MS in the acute phase of transverse myelitis.

METHODS

In a randomized, placebo-controlled trial, 30 patients who had their first episode of cervical myelitis with quadriparesis presentation, with the final diagnosis of MS, were randomly divided into two equal groups. The intervention group received intravenous methylprednisolone (IVMP) for 7 days plus fampridine. The placebo group received IVMP for 7 days plus placebo. To compare the treatment results, we compared the Barthel index (BI) scores of the groups at the start of the trial and the 21st day after the start of treatment.

RESULTS

There was no significant difference in baseline characteristics between the intervention and placebo groups in terms of mean age, sex, and mean admission BI (p > 0.05). Mean (SD) admission BI in placebo and intervention groups was 27.20 (7.341) and 27.87(5.78), respectively (p = 0.784). The measured mean (SD) BI after treatment was 48.73 (15.54) in the placebo and 64.93 (11.81) in the intervention group (p = 0.003) after 3 weeks.

CONCLUSION

Using fampridine plus IVMP in the acute phase of transverse myelitis in MS patients improved the disease's symptoms and increased the daily activity ability of patients.

Evaluation of the Validity and Reliability of Connected Insoles to Measure Gait Parameters in Healthy Adults

The continuous, accurate and reliable estimation of gait parameters as a measure of mobility is essential to assess the loss of functional capacity related to the progression of disease. Connected insoles are suitable wearable devices which allow precise, continuous, remote and passive gait assessment. The data of 25 healthy volunteers aged 20 to 77 years were analysed in the study to validate gait parameters (stride length, velocity, stance, swing, step and single support durations and cadence) measured by FeetMe^® insoles against the GAITRite^® mat reference. The mean values and the values of variability were calculated per subject for GAITRite^® and insoles. A t-test and Levene’s test were used to compare the gait parameters for means and variances, respectively, obtained for both devices. Additionally, measures of bias, standard deviation of differences, Pearson’s correlation and intraclass correlation were analysed to explore overall agreement between the two devices. No significant differences in mean and variance between the two devices were detected. Pearson’s correlation coefficients of averaged gait estimates were higher than 0.98 and 0.8, respectively, for unipedal and bipedal gait parameters, supporting a high level of agreement between the two devices. The connected insoles are therefore a device equivalent to GAITRite^® to estimate the mean and variability of gait parameters.

Outcome measures assisting treatment optimization in multiple sclerosis

Objective

To review instruments used to assess disease stability or progression in persons with multiple sclerosis (pwMS) that can guide clinicians in optimizing therapy.

Methods

A non-systematic review of scientific literature was undertaken to explore modalities of monitoring symptoms and the disease evolution of MS.

Results

Multiple outcome measures, or tools, have been developed for use in MS research as well as for the clinical management of pwMS. Beginning with the Expanded Disability Status Scale, introduced in 1983, clinicians and researchers have developed monitoring modalities to assess all aspects of MS and the neurological impairment it causes.

Conclusions

Much progress has been made in recent decades for the management of MS and for the evaluation of disease progression. New technology, such as wearable sensors, will provide new opportunities to better understand changes in function, dexterity, and cognition. Essential work over the decades since EDSS was introduced continues to improve our ability to treat this debilitating disease.

Effects of prolonged-release fampridine on multiple sclerosis-related gait impairments. A crossover, double-blinded, placebo-controlled study

BACKGROUND

People with multiple sclerosis have reduced walking speed and impaired gait pattern. Prolonged release-fampridine is a potassium channel blocker that improves nerve conduction in patients with multiple sclerosis, leading to walking benefits. Whether fampridine alters gait pattern is unknown.

METHODS

In this crossover, randomized controlled trial, patients with multiple sclerosis were tested for responder status during a 4-week run-in period. Patients were considered responders if they improved their 25-ft walk test by 10% and improved their perceived walking capacity. Responders were randomized to prolonged release-fampridine (10 mg b.i.d.) or placebo for a 6-week period. After a 2-week wash-out period, they were allocated to the other treatment for 6 weeks. Participants were assessed before and after both conditions. Three-dimensional gait analysis assessed kinematic, kinetic, mechanic and energetic variables while walking on a treadmill at comfortable speed. Six-minute walk test and 25-ft walk test were used to assess walking speed on middle and short-distances, respectively. Patient-reported outcome measures were also used. Repeated measures ANCOVAs were applied to assess the treatment effects.

FINDINGS

Out of 39 included patients, 24 responders (12 women; Expanded Disability Status Scale:4.25[4-5]; age:46 ± 10 years; maximal speed:0.93 ± 0.38 m·s^-1) were identified. Among them, prolonged release-fampridine reduced the external mechanical work (-0.039 J·kg^-1·m^-1;p = 0.02), and improved knee flexion during swing phase (+5.3°; p = 0.02). No differences were found in other walking tests and patient-reported outcomes, at group-level.

INTERPRETATION

Prolonged release-fampridine increases knee flexion during swing phase and lowers mechanical external work. Whether these changes are related to clinically meaningful improvements in walking capacity and other functional variables should be further investigated.

Dalfampridine improves slowed processing speed in multiple sclerosis patients with mild motor disability: post hoc analysis of a randomized controlled trial

Objective

To evaluate baseline characteristics predictive of improving information processing speed in multiple sclerosis (MS) and the relationship between cognitive and motor response to dalfampridine (DA) treatment.

Methods

This is a post hoc analysis of a randomized, double-blind, placebo-controlled trial in patients with MS randomized to receive DA 10 mg or placebo twice daily for 12 consecutive weeks. Here, we include only data from 71 patients in the arm treated with DA. According to the median value of Symbol Digit Modalities Test (SDMT) response, patients were categorized as "full responders" (FR) or "partially responders" (PR).

Results

There was higher possibility of being FR in the presence of a baseline lower Expanded Disability Status Scale [odds ratio (OR) 0.69; 95% confidence interval (CI) 0.5-0.97, p = 0.034], a higher Multiple Sclerosis Functional Composite value (OR 1.37; 95%CI 1.05-1.8, p = 0.022), a lower Timed 25-Foot Walk Test (OR 0.76; 95% CI 0.6-0.98, p = 0.033), and a lower 9-Hole Peg Test with dominant hand (OR 0.92; 95% CI 0.86-0.99, p = 0.029). FR group did not show any significant improvement of motor performance compared with PR group.

Conclusion

The current analysis shows that in MS patients with cognitive deficit, the greatest improvement in SDMT provided by DA was observed in patients with milder motor impairment; cognitive and motor responses to treatments are not related.

Trial registration

EU Clinical Trials Register; ID 2013-002558-64 (https://www.clinicaltrialsregister.eu/ctr-search/search?query=2013-002558-64).

Efficacy and safety of fampridine for walking disability in multiple sclerosis

Fampridine is the only drug approved for the treatment of walking impairment in multiple sclerosis. Around a third of the patients on treatment obtained an improvement in walking speed during the development phase. The effects are clinically significant, appear soon after the start of the treatment and are long-lasting, but disappear soon after the drug is withdrawn. In the real-world setting, the number of patients with a significant response to the treatment seems to be higher (around 70%). The tolerance is good, with mild to moderate, and transient adverse events. The most commonly reported are insomnia, headache, fatigue, back pain, dizziness, nausea and balance disorders. The main contraindications are a history of seizures, renal impairment and concomitant treatment with OCT2 inhibitors.

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.

Dalfampridine to Improve Balance in Multiple Sclerosis: Substudy from a Randomized Placebo-Controlled Trial

This was a substudy of a randomized, double-blind, placebo-controlled trial originally designed to explore the effect of dalfampridine on information processing speed (2013-002558-64 EU Clinical Trials Register) in patients with multiple sclerosis (MS). A total of 120 patients were originally randomized in a 2:1 ratio to receive dalfampridine 10 mg or placebo twice daily for 12 weeks. Here, we sought to explore the effect of dalfampridine on static balance in single-task and dual-task conditions in a subgroup of 41 patients. They underwent static posturography in quiet standing (single-task) and while performing the Stroop test (dual-task) at randomization (baseline), after 12 weeks and after a 4-week wash-out period. Baseline characteristics of active group (n = 27) did not differ from those of placebo group (n = 14). Dalfampridine treatment was associated with better balance control than placebo in both single-task (F = 4.80, p = 0.034) and dual-task (F = 6.42, p = 0.015) conditions, with small-to-moderate effect sizes (Cohen's f2 = 0.122-0.162). The beneficial effect of dalfampridine was not retained 4 weeks after its discontinuation. The rate of accidental falls per month did not differ between the two groups (p = 0.12). Our preliminary findings suggest that dalfampridine can be considered a potential option to treat balance impairment due to MS. Larger sample sizes are needed to verify if the beneficial effect of dalfampridine on balance can be translated into a reduced risk of accidental falls.

Effects of Fampridine in People with Multiple Sclerosis: A Systematic Review and Meta-analysis

BACKGROUND

Prolonged-release (PR) fampridine is a potassium channel blocker used as a symptomatic treatment for walking disability in patients with multiple sclerosis (MS). Its clinical effects in such patients have not been systematically reviewed, and may be more wide-ranging than expected.

OBJECTIVES

To summarize the evidence on the effects of PR fampridine in patients with MS.

METHODS

A systematic search of Pubmed, Scopus (including EMBASE), and PsycINFO (completed in 01/2019) was carried out to identify randomized controlled trials (RCT) that compared PR fampridine to placebo. When appropriate, data were pooled using a random-effects model, and standardized mean differences (SMD) were computed. Study quality was assessed using the Downs and Black checklist. PRISMA guidelines were followed. All retrieved functional outcomes were categorized according to the International Classification of Functioning, Disability and Health (ICF).

RESULTS

A total of 706 articles were screened for inclusion. Twenty RCTs involving 2616 patients met the eligibility criteria. Most studies were of good-to-excellent quality. PR fampridine administration resulted in significant benefits in relation to walking short distances (SMD: 1.23 (95% IC 0.65-1.81)) and perceived walking capacity (0.64 (0.27-1.02)). Its effects on muscle strength and middle-distance walking were not significant (0.53 (- 0.04 to 1.10) and 0.31 (- 0.18 to 0.80), respectively). No effect on higher-level cognitive functions (- 0.07 (- 0.58 to 0.45)) or hand and arm use (0.16 (- 0.33 to 0.64)) was observed. Individual studies reported effects on other outcomes across the ICF domains.

CONCLUSIONS

There is strong evidence that PR fampridine exerts strong effects on the ability to walk short distances and on perceived walking capacity. Other effects of PR fampridine according to the ICF are possible but still unclear.

Evaluating dalfampridine for the treatment of relapsing-remitting multiple sclerosis: does it add to the treatment armamentarium?

Introduction: Multiple sclerosis (MS) is a demyelinating disease, causing axonal damage and disability. Dalfampridine (DAL) is an extended-release formulation of 4-aminopyridine (4AP) and broad-spectrum voltage-dependent potassium channel blocker that is reported to improve motor, visual and cognitive functions. Furthermore, it is presently the only approved drug for walking impairment in MS. Areas covered: Herein, the authors evaluate DAL as a relapsing-remitting MS treatment, reporting and commenting on all aspects of the drug including its chemistry, safety, pharmacokinetics, and cost-effectiveness. A bibliographic search was performed on PubMed using the terms 'dalfampridine OR fampridine OR 4-aminopyridine'. Expert opinion: Evidence from post-marketing studies suggests that DAL, consistent with the effects of 4AP, may not only improve walking speed, but also arm function, fatigue, mood and cognition through restored nerve conduction in central nervous system demyelinated areas. Long-term safety data confirm that the approved dose of 10 mg twice daily is generally well tolerated. However, despite the reported efficacy, the extent of the benefits is limited in real life activities, although significant improvements have been demonstrated in the clinical setting. Patients often complain of side effects (such as cramps and painful paraesthesia) or lack of efficacy. Also, its considerably higher pricing in comparison to 4AP represents an important limitation.

Familiarization with treadmill walking: How much is enough?

Treadmill-based gait analysis is widely used to investigate walking pathologies and quantify treatment effects on locomotion. Differential sensorimotor conditions during overground vs. treadmill walking necessitate initial familiarization to treadmill walking. Currently, there is no standardized treadmill acclimatization protocol and insufficient familiarization potentially confounds analyses. We monitored initial adaptations to treadmill walking in 40 healthy adults. Twenty-six walking parameters were assessed over 10 minutes with marker-based kinematic analysis and acclimatization profiles were generated. While 16 walking parameters demonstrated initial acclimatization followed by plateau performance, ten parameters remained stable. Distal lower limb control including ankle range of motion, toe trajectory and foot clearance underwent substantial adaptations. Moreover, intralimb coordination and gait variability also demonstrated acclimatization, while measures of symmetry and interlimb coordination did not. All parameters exhibiting a plateau after acclimatization did so within 6–7 minutes (425 strides). Older participants and those naïve to treadmill walking showed adaptations with higher amplitudes but over similar timescales. Our results suggest a minimum of 6 minutes treadmill acclimatization is required to reach a stable performance, and that this should suffice for both older and naïve healthy adults. The presented data aids in optimizing treadmill-based gait analysis and contributes to improving locomotor assessments in research and clinical settings.

Assessment of Clinically Meaningful Improvements in Self-Reported Walking Ability in Participants with Multiple Sclerosis: Results from the Randomized, Double-Blind, Phase III ENHANCE Trial of Prolonged-Release Fampridine

BACKGROUND

Walking impairment is a hallmark of multiple sclerosis (MS). It affects > 90% of individuals over time, reducing independence and negatively impacting health-related quality of life, productivity, and daily activities. Walking impairment is consistently reported as one of the most distressing impairments by individuals with MS. Prolonged-release (PR)-fampridine previously has been shown to improve objectively measured walking speed in walking-impaired adults with MS. The impact of PR-fampridine from the perspective of the individual with MS warrants full and detailed examination.

OBJECTIVE

The objective of this study was to evaluate whether PR-fampridine has a clinically meaningful effect on self-reported walking ability in walking-impaired participants with MS.

METHODS

ENHANCE was a phase III, randomized, double-blind, placebo-controlled study of PR-fampridine 10 mg twice daily in walking-impaired individuals age 18-70 years with either relapsing or progressive forms of MS and an Expanded Disability Status Scale (EDSS) score of 4.0-7.0 at screening. Participants were stratified by EDSS score (≤ 6.0 or 6.5-7.0) at randomization to ensure a balanced level of disability in the treatment groups. The primary endpoint was the proportion of participants with a mean improvement in the 12-item Multiple Sclerosis Walking Scale (MSWS-12) score exceeding the predefined threshold for clinically meaningful improvement (≥ 8 points) over 24 weeks. Secondary endpoints included the proportion with ≥ 15% improvement in Timed Up and Go (TUG) speed, and mean changes in Multiple Sclerosis Impact Scale physical impact subscale (MSIS-29 PHYS), Berg Balance Scale (BBS), and ABILHAND scores over 24 weeks.

RESULTS

In total, 636 participants with MS were randomized (PR-fampridine, n = 317; placebo, n = 319; modified intention-to-treat sample: PR-fampridine, n = 315; placebo, n = 318). At baseline in the PR-fampridine and placebo groups, 46% and 51% had a progressive form of MS, median [range] EDSS scores were 6.0 [4.0-7.0] and 5.5 [4.0-7.0], mean [range] MSWS-12 scores were 63.6 [0-100] and 65.4 [0-100], and mean [range] TUG speed was 0.38 [0.0-1.0] and 0.38 [0.0-1.2] feet/s, respectively. A significantly higher percentage of PR-fampridine-treated participants (136/315 [43.2%]) had clinically meaningful improvement in MSWS-12 score over 24 weeks versus placebo (107/318 [33.6%]; odds ratio 1.61 [95% confidence interval 1.15-2.26]; p = 0.006). For PR-fampridine versus placebo, significantly more participants had a ≥ 15% improvement in TUG speed, and there was significantly greater mean improvement in MSIS-29 PHYS score (p < 0.05); numerical improvements that were not statistically significant were observed in BBS/ABILHAND. Adverse events that were more common in the PR-fampridine group than placebo group (difference ≥ 3%) by Medical Dictionary for Regulatory Activities (MedDRA^®) Preferred Term were urinary tract infection and insomnia. There were no seizures reported.

CONCLUSIONS

PR-fampridine treatment resulted in sustained, clinically meaningful improvements over 24 weeks in self-reported walking and functional ability in walking-disabled participants with MS. CLINICALTRIALS.

GOV IDENTIFIER

NCT02219932.

Multiple Sclerosis: An Update for Home Healthcare Clinicians

Multiple sclerosis (MS) is a chronic neurologic disease and the most common cause of nontraumatic disability in young adults in the United States. It strikes adults in the prime of life and can gradually diminish physical and mental function, affect relationships, employment, financial capacity, and independence. Neurologic symptoms fluctuate in a pattern of remissions and exacerbations for the majority of those with MS. A multidisciplinary treatment approach is essential. There are a wide number of medications that can be used. Treating the disease at an early stage within the first 5 years of clinical symptom onset is optimal. Home healthcare clinicians can use assessment tools to evaluate disease progression, teach the patient and family how to live with the disorder, and monitor the patient for medication side effects.

Prolonged-release fampridine in multiple sclerosis: clinical data and real-world experience. Report of an expert meeting

Prolonged-release (PR) fampridine is the only approved medication to improve walking in multiple sclerosis (MS), having been shown to produce a clinically meaningful improvement in walking ability in the subset of MS patients with Expanded Disability Status Scale 4-7. Recent responder subgroup analyses in the phase III ENHANCE study show a large effect size in terms of an increase of 20.58 points on the patient-reported 12-item MS Walking Scale in the 43% of patients classified as responders to PR-fampridine, corresponding to a standardized response mean of 1.68. Use of PR-fampridine in clinical practice varies across Europe, depending partly on whether it is reimbursed. A group of European MS experts met in June 2017 to discuss their experience with using PR-fampridine, including their views on the patient population for treatment, assessment of treatment response, re-testing and re-treatment, and stopping criteria. This article summarizes the experts' opinions on how PR-fampridine can be used in real-world clinical practice to optimize the benefits to people with MS with impaired walking ability.

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.

Combined walking outcome measures identify clinically meaningful response to prolonged-release fampridine

Background

Gait impairment is common in multiple sclerosis (MS) and negatively impacts patients' health-related quality of life (HRQoL). Prolonged-release fampridine (PR-fam) improves walking speed, but it is unclear which walking measures are the most suitable for identifying treatment response. Our aim was to assess the effect of PR-fam and the outcome measures that best identify short- and long-term clinically meaningful response.

Methods

We conducted a prospective study in 32 MS patients treated with PR-fam for a year. The assessments at 2 weeks, 3, 6 and 12 months included: timed 25-foot walk (T25FW), 6-minute walk test (6MWT), MS Walking Scale-12 (MSWS-12), a five-level version of the EuroQoL-5 dimensions, and accelerometry. PR-fam response was defined as an improvement in T25FW ⩾20%.

Results

Twenty-five (78%) patients were considered responders after 2 weeks of PR-fam and improved significantly in all measures. Responders to T25FW and MSWS-12 (n = 19) showed a significant improvement in HRQoL and accelerometer data compared with responders only to T25FW (n = 6). At 1 year, 15/20 (75%) patients remained responders, but only those with permanent response to T25FW and MSWS-12 (n = 8; 53%) showed a significant improvement in 6MWT and HRQoL.

Conclusion

The combination of T25FW and MSWS-12 identify better those patients with a clinically significant benefit of PR-fam.

Restoring Axonal Function with 4-Aminopyridine: Clinical Efficacy in Multiple Sclerosis and Beyond

The oral potassium channel blocker 4-aminopyridine has been used in various neurological conditions for decades. Numerous case reports and studies have supported its clinical efficacy in ameliorating the clinical presentation of certain neurological disorders. However, its short half-life, erratic drug levels, and safety-related dose restrictions limited its use as a self-compounded drug in clinical practice. This changed with the introduction of a prolonged-release formulation, which was successfully tested in patients with multiple sclerosis. It was fully approved by the US FDA in January 2010 but initially received only conditional approval from the European Medicines Agency (EMA) in July 2011. After additional clinical studies, this conditional approval was changed to unrestricted approval in August 2017. This article reviews and discusses these recent studies and places aminopyridines and their clinical utility into the context of a broader spectrum of neurological disorders, where clinical efficacy has been suggested. In 2010, prolonged-release 4-aminopyridine became the first drug specifically licensed to improve walking in patients with multiple sclerosis. About one-third of patients across disease courses benefit from this treatment. In addition, various reports indicate clinical efficacy beyond multiple sclerosis, which may broaden its use in clinical practice.

Multiple sclerosis

Multiple sclerosis continues to be a challenging and disabling condition but there is now greater understanding of the underlying genetic and environmental factors that drive the condition, including low vitamin D levels, cigarette smoking, and obesity. Early and accurate diagnosis is crucial and is supported by diagnostic criteria, incorporating imaging and spinal fluid abnormalities for those presenting with a clinically isolated syndrome. Importantly, there is an extensive therapeutic armamentarium, both oral and by infusion, for those with the relapsing remitting form of the disease. Careful consideration is required when choosing the correct treatment, balancing the side-effect profile with efficacy and escalating as clinically appropriate. This move towards more personalised medicine is supported by a clinical guideline published in 2018. Finally, a comprehensive management programme is strongly recommended for all patients with multiple sclerosis, enhancing health-related quality of life through advocating wellness, addressing aggravating factors, and managing comorbidities. The greatest remaining challenge for multiple sclerosis is the development of treatments incorporating neuroprotection and remyelination to treat and ultimately prevent the disabling, progressive forms of the condition.

Profiling walking dysfunction in multiple sclerosis: characterisation, classification and progression over time

Gait dysfunction is a common and relevant symptom in multiple sclerosis (MS). This study aimed to profile gait pathology in gait-impaired patients with MS using comprehensive 3D gait analysis and clinical walking tests. Thirty-seven patients with MS walked on the treadmill at their individual, sustainable speed while 20 healthy control subjects walked at all the different patient's paces, allowing for comparisons independent of walking velocity. Kinematic analysis revealed pronounced restrictions in knee and ankle joint excursion, increased gait variability and asymmetry along with impaired dynamic stability in patients. The most discriminative single gait parameter, differentiating patients from controls with an accuracy of 83.3% (χ2 test; p = 0.0001), was reduced knee range of motion. Based on hierarchical cluster and principal component analysis, three principal pathological gait patterns were identified: a spastic-paretic, an ataxia-like, and an unstable gait. Follow-up assessments after 1 year indicated deterioration of walking function, particularly in patients with spastic-paretic gait patterns. Our findings suggest that impaired knee/ankle control is common in patients with MS. Personalised gait profiles and clustering algorithms may be promising tools for stratifying patients and to inform patient-tailored exercise programs. Responsive, objective outcome measures are important for monitoring disease progression and treatment effects in MS trials.

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

Oral fampridine prolonged release (PR) [Fampyra^®] is a lipid-soluble selective potassium channel blocker that is approved in the EU for the improvement of walking in adult multiple sclerosis (MS) patients with walking disability (expanded disability status scale score of 4-7). In clinical trials (MS-F203 and MS-F204) using an objective measure of walking improvement [the timed 25-foot walk (T25FW)], more than one-third of patients receiving fampridine PR achieved a consistent on-treatment improvement in walking speed (i.e. became TW responders) over 9-14 weeks of treatment. Fampridine PR recipients who fulfilled the definition of TW responder had mean improvements of ≈25% from baseline in T25FW walking speed. In a clinical trial (ENHANCE) that used a patient-rated measure of walking improvement [12-item MS walking scale (MSWS-12)], a significantly greater proportion of fampridine PR recipients than placebo recipients achieved a ≥8-point improvement on the MSWS-12 with 24 weeks of treatment. Where reported, adverse events were mostly mild or moderate in severity, and generally consistent with the underlying disease or mechanism of action of fampridine PR. Fampridine PR is a useful treatment option to consider in adult MS patients with walking disability.

A reduced somatosensory gating response in individuals with multiple sclerosis is related to walking impairment

When identical stimuli are presented in rapid temporal succession, neural responses to the second stimulation are often weaker than those observed for the first. This phenomenon is termed sensory gating and is believed to be an adaptive feature that helps prevent higher-order cortical centers from being flooded with unnecessary information. Recently, sensory gating in the somatosensory system has been linked to deficits in tactile discrimination. Additionally, studies have linked poor tactile discrimination with impaired walking and balance in individuals with multiple sclerosis (MS). In this study, we examine the neural basis of somatosensory gating in patients with MS and healthy controls and assess the relationship between somatosensory gating and walking performance. We used magnetoencephalography to record neural responses to paired-pulse electrical stimulation applied to the right posterior tibial nerve. All participants also walked across a digital mat, which recorded their spatiotemporal gait kinematics. Our results showed the amplitude of the response to the second stimulation was sharply reduced only in controls, resulting in a significantly reduced somatosensory gating in the patients with MS. No group differences were observed in the amplitude of the response to the first stimulation nor the latency of the neural response to either the first or second stimulation. Interestingly, the altered somatosensory gating responses were correlated with aberrant spatiotemporal gait kinematics in the patients with MS. These results suggest that inhibitory GABA circuits may be altered in patients with MS, which impacts somatosensory gating and contributes to the motor performance deficits seen in these patients.NEW & NOTEWORTHY We aimed to determine whether somatosensory gating in patients with multiple sclerosis (MS) differed compared with healthy controls and whether a relationship exists between somatosensory gating and walking performance. We found reduced somatosensory gating responses in patients with MS, and these altered somatosensory gating responses were correlated with the mobility impairments. These novel findings show that somatosensory gating is impaired in patients with MS and is related to the mobility impairments seen in these patients.

Minimum toe clearance: probing the neural control of locomotion

Minimum toe clearance (MTC) occurs during a highly dynamic phase of the gait cycle and is associated with the highest risk of unintentional contact with obstacles or the ground. Age, cognitive function, attention and visual feedback affect foot clearance but how these factors interact to influence MTC control is not fully understood. We measured MTC in 121 healthy individuals aged 20–80 under four treadmill walking conditions; normal walking, lower visual field restriction and two Stroop colour/word naming tasks of two difficulty levels. Competition for cognitive and attentional resources from the Stroop task resulted in significantly lower mean MTC in older adults, with the difficult Stroop task associated with a higher frequency of extremely low MTC values and subsequently an increased modelled probability of tripping in this group. While older adults responded to visual restriction by markedly skewing MTC distributions towards higher values, this condition was also associated with frequent, extremely low MTC values. We reveal task-specific, age-dependent patterns of MTC control in healthy adults. Age-related differences are most pronounced during heavy, distracting cognitive load. Analysis of critically-low MTC values during dual-task walking may have utility in the evaluation of locomotor control and fall risk in older adults and patients with motor control deficits.