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

Dalfampridine in the treatment of primary fatigue in patients with multiple sclerosis: a randomized clinical trail

INTRODUCTION

Fatigue is a highly prevalent debilitating symptom among patients with multiple sclerosis (PwMS), which markedly affects the quality of life. The present study aimed to evaluate the effect of extended-release fampridine on fatigue in PwMS.

METHODS

This was a randomized, double-blind clinical trial on 77 PwMS with a complaint of fatigue, aged over 18 years old, randomized to extended-release fampridine (n = 44) or placebo (n = 35) for 12 weeks. Fatigue and motor function were assessed at baseline and end point.

RESULTS

A total of 88 patients were recruited, of whom 77 were analyzed. 80.5% were female, with a median age of 38. 87% were diagnosed with relapsing-remitting MS (RRMS) with a median disease duration of 96 months. Fingolimod (37.7%) was considered the most frequently used DMT, followed by ani-CD20s (32.5%). The total median MFIS score was 43.5 and 37 in the fampridine and placebo groups which were not significantly different (p > 0.05). After 12 weeks, the total MFIS improved in both groups compared to the baseline, which was significant in the active group (p = 0.04). However, the final end point total MFIS was still comparable between the two groups (p = 0.11).

CONCLUSION

The present study revealed a positive short-term effect of extended-release fampridine on MFIS in PwMS. However, this effect was not significantly superior to the placebo.

Social Cognition Impairments in Association to Clinical, Cognitive, Mood, and Fatigue Features in Multiple Sclerosis: A Study Protocol

Multiple sclerosis (MS) is a chronic immune-mediated disease of the central nervous system (CNS), characterized by the diffuse grey and white matter damage. Cognitive impairment (CI) is a frequent clinical feature in patients with MS (PwMS) that can be prevalent even in early disease stages, affecting the physical activity and active social participation of PwMS. Limited information is available regarding the influence of MS in social cognition (SC), which may occur independently from the overall neurocognitive dysfunction. In addition, the available information regarding the factors that influence SC in PwMS is limited, e.g., factors such as a patient's physical disability, different cognitive phenotypes, mood status, fatigue. Considering that SC is an important domain of CI in MS and may contribute to subjects' social participation and quality of life, we herein conceptualize and present the methodological design of a cross-sectional study in 100 PwMS of different disease subtypes. The study aims (a) to characterize SC impairment in PwMS in the Greek population and (b) to unveil the relationship between clinical symptoms, phenotypes of CI, mood status and fatigue in PwMS and the potential underlying impairment on tasks of SC.

Current perspectives on the diagnosis and management of fatigue in multiple sclerosis

INTRODUCTION

Fatigue is a common and debilitating symptom among multiple sclerosis (MS) patients with a prevalence up to 81% and with a considerable impact on quality of life. However, its subjective nature makes it difficult to define and quantify in clinical practice. Research aimed at a more precise definition and knowledge of this construct is thus continuously growing.

AREAS COVERED

This review summarizes the most relevant updates available on PubMed up to July 1^st 2022 regarding: the assessment methods that aim to measure the concept of fatigue (as opposed to fatigability), the possible treatment pathways currently available to clinicians, interconnection with the pathophysiological substrates and with the common comorbidities of MS, such as depression and mood disorders.

EXPERT OPINION

The in-depth study of fatigue can help to better understand its actual impact on MS patients and can stimulate clinicians towards a more valid approach, through a targeted analysis of this symptom. Considering fatigue from a multidimensional perspective allows the use of patient-tailored methods for its identification and subsequent treatment by different professional figures. Better identification of methods and treatment pathways would reduce the extremely negative impact of fatigue on MS patients' quality of life.

Multiple sclerosis-related fatigue lacks a unified definition: A narrative review

Fatigue is the most common symptom in multiple sclerosis (MS). Although MS-related fatigue (MS-F) strongly affects quality of life and social performance of patients, there is currently a lack of knowledge about its pathophysiology, which in turns leads to poor objective diagnosis and management. Recent studies have attempted to explain potential etiologies as well as treatments for MS-F. However, it seems that without a consensus on its nature, these data could not provide a route to a successful approach. In this Article, we review definitions, epidemiology, risk factors and correlated comorbidities, pathophysiology, assessment methods, neuroimaging findings, and pharmacological and nonpharmacological treatments of MS-F. Further studies are warranted to define fatigue in MS patients more accurately, which could result in precise diagnosis and management.

Gonadotropin-Releasing Hormone (GnRH) Neuron Potassium Currents and Excitability in Both Sexes Exhibit Minimal Changes upon Removal of Negative Feedback

Gonadotropin-releasing hormone (GnRH) drives pituitary secretion of luteinizing hormone and follicle-stimulating hormone, which in turn regulate gonadal functions including steroidogenesis. The pattern of GnRH release and thus fertility depend on gonadal steroid feedback. Under homeostatic (negative) feedback conditions, removal of the gonads from either females or males increases the amplitude and frequency of GnRH release and alters the long-term firing pattern of these neurons in brain slices. The neurobiological mechanisms intrinsic to GnRH neurons that are altered by homeostatic feedback are not well studied and have not been compared between sexes. During estradiol-positive feedback, which is unique to females, there are correlated changes in voltage-gated potassium currents and neuronal excitability. We thus hypothesized that these same mechanisms would be engaged in homeostatic negative feedback. Voltage-gated potassium channels play a direct role in setting excitability and action potential properties. Whole-cell patch-clamp recordings of GFP-identified GnRH neurons in brain slices from sham-operated and castrated adult female and male mice were made to assess fast and slow inactivating potassium currents as well as action potential properties. Surprisingly, no changes were observed among groups in most potassium current properties, input resistance, or capacitance, and this was reflected in a lack of differences in excitability and specific action potential properties. These results support the concept that, in contrast to positive feedback, steroid-negative feedback regulation of GnRH neurons in both sexes is likely conveyed to GnRH neurons via mechanisms that do not induce major changes in the biophysical properties of these cells.

Effects of antipsychotic drugs and potassium channel modulators on spectral properties of local field potentials in mouse hippocampus and pre-frontal cortex

Local field potentials (LFPs) recorded intracranially display a range of location-specific oscillatory spectra which have been related to cognitive processes. Although the mechanisms producing LFPs are not completely understood, it is likely that voltage-gated ion channels which produce action potentials and patterned discharges play a significant role. It is also known that antipsychotic drugs (APDs) affect LFP spectra and a direct inhibitory effect on voltage-gated potassium channels has been reported. Additionally, voltage-gated potassium channels have been implicated in the pathophysiology of schizophrenia, a disorder for which APDs are primary therapies. In this study we sought to: i) better characterise the effects of two APDs on LFPs spectra and connectivity measures and ii) examine the effects of potassium channel modulators on LFPs and potential overlap of effects with APDs. Intracranial electrodes were implanted in hippocampus (HIP) and pre-frontal cortex (PFC) of C57BL/6J mice; power spectra, coherence and phase-amplitude cross-frequency coupling were measured. Drugs tested were APDs haloperidol and clozapine as well as voltage-gated potassium channel modulators (KVMs) 4-aminopyridine (4-AP), tetraethylammonium, retigabine and E-4031. Both APDs and KVMs significantly reduced gamma power except 4-AP, which conversely increased gamma power. Clozapine and retigabine additionally reduced gamma coherence between HIP and PFC, while 4-AP demonstrated the opposite effect. Phase-amplitude coupling between theta and gamma oscillations in HIP was significantly reduced by the administration of haloperidol and retigabine. These results provide previously undescribed effects of APDs on LFP properties and demonstrate novel modulation of LFP characteristics by KVMs that intriguingly overlap with the APD effects.

A Prospective, Observational, Cohort Study to Assess the Efficacy and Safety of Prolonged-Release Fampridine in Cognition, Fatigue, Depression, and Quality of Life in Multiple Sclerosis Patients: The FAMILY Study

Introduction

The efficacy of prolonged-release fampridine (PR-FAM) may extend in multiple sclerosis (MS) beyond walking ability. The objective of this study was to evaluate the effect of PR-FAM treatment on cognition, fatigue, depression, and quality of life (QoL) in adult patients with MS in a real-world setting.

Methods

FAMILY was a multi-center, prospective, observational, real-world cohort study of MS patients receiving PR-FAM in the outpatient setting. Patients were treated as per PR-FAM’s local prescribing information for 6 months. Standardized protocols and questionnaires were used to evaluate changes in cognition (PASAT; Paced Auditory Serial Addition Test), fatigue (MFIS; Modified Fatigue Impact Scale), depression (BDI-II; Beck Depression Inventory-II) and QoL (MusiQoL; MS International Quality-of-Life questionnaire, MSIS-29; Multiple Sclerosis Impact Scale: PHYS and PSYCH subscales) at 3 and 6 months compared to baseline.

Results

In total, 102 eligible patients from 8 sites in Greece were analysed, of whom 92 completed the study and 10 discontinued. At 6 months, PR-FAM treatment resulted in improvements from baseline in PASAT-3′′ (p = 0.044), MFIS (p < 0.001), BDI-II (p < 0.001), MusiQoL (p < 0.001) and MSIS-29-PHYS (p = 0.012) and MSIS-PSYCH (p < 0.001). A positive effect was evident already at 3 months in PASAT-3′′ (ns), MFIS (p = 0.020), BDI-II (p = 0.034), MusiQoL (p = 0.001), MSIS-29-PHYS (ns) and MSIS-29-PSYCH (p < 0.001).

Conclusions

This observational study provides new data to the current literature in support of PR-FAM’s positive effects in cognition, fatigue, depression, and QoL in a large, heterogeneous group of Greek MS patients in the real-world setting.

Trial Registration

ClinicalTrials.gov identifier, NCT03164018.

Supplementary Material

The online version of this article (10.1007/s12325-020-01606-5) contains supplementary material, which is available to authorized users.

Safety, Patient-Reported Well-Being, and Physician-Reported Assessment of Walking Ability in Patients with Multiple Sclerosis for Prolonged-Release Fampridine Treatment in Routine Clinical Practice: Results of the LIBERATE Study

BACKGROUND

Prolonged-release fampridine (PR-FAM) 10-mg tablet twice daily is the only approved pharmacological treatment for improvement of walking ability in adults with multiple sclerosis (MS). LIBERATE assessed the safety/effectiveness of PR-FAM in the real-world.

OBJECTIVES

The aim of this study was to collect additional safety data, including the incidence rate of seizures and other adverse events (AEs) of interest, from patients with MS taking PR-FAM in routine clinical practice (including patients aged ≥ 65 years and those with pre-existing cardiovascular risk factors). Other objectives included change over time in patient-reported evaluation of physical and psychological impact of MS while taking PR-FAM, and change over time in physician-reported assessment of walking ability in MS patients taking PR-FAM.

METHODS

Patients with MS newly prescribed PR-FAM were recruited (201 sites, 13 countries). Demographic/safety data were collected at enrolment through 12 months. Physician-rated Clinical Global Impression of Improvement (CGI-I) scores for walking ability, and Multiple Sclerosis Impact Scale-29 (MSIS-29) were assessed.

RESULTS

Safety analysis included 4646 patients with 3534.8 patient-years of exposure; median (range) age, 52.6 (21-85) years, 87.3% < 65 years, and 65.7% women. Treatment-emergent AEs (TEAEs) were reported in 2448 (52.7%) patients, and serious TEAEs were reported in 279 (6.0%) patients, of whom 37 (< 1%) experienced treatment-emergent serious AEs (TESAEs) considered related to PR-FAM. AEs of special interest (AESI) occurred in 1799 (38.7%) patients, and serious AESI in 128 (2.8%) patients. Seventeen (< 1%) patients experienced actual events of seizure. Overall, 1158 (24.9%) patients discontinued treatment due to lack of efficacy. At 12 months, a greater proportion of patients on-treatment had improvement from baseline in CGI-I for walking ability versus those who discontinued (61% vs. 11%; p <  0.001). MSIS-29 physical impact score improved significantly for patients on-treatment for 12 months versus those who discontinued (mean change, baseline to 12 months: - 9.99 vs. - 0.34 points; p <  0.001). Results were similar for MSIS-29 psychological impact.

CONCLUSION

No new safety concerns were identified in this real-world study, suggesting that routine risk-minimization measures are effective. CGI-I and MSIS-29 scores after 12 months treatment with PR-FAM treatment show clinical benefits consistent with those previously reported.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01480063.

Pharmacotherapy in multiple sclerosis-induced cognitive impairment: A systematic review and meta-analysis

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) commonly complicated by cognitive impairment. Unfortunately, no medical therapy has been proved to improve cognitive problems in these patients. This meta-analysis investigated the effectiveness of different categories of drugs on the minimal assessment of cognitive function in MS (MACFIMS)-related tasks outcome in MS patients. To this end, a systematic evaluation was conducted using PubMed, Google Scholar, and Scopus databases. Among a total of 128 publications, 31 studies met our inclusion criteria, and 22 included in the meta-analysis. We found that symbol digit modalities test (SDMT), paced auditory serial addition test (PASAT), controlled oral word association test (COWAT), and California verbal learning test (CVLT) were the most frequently reported tasks in included studies. The frequently reported drugs were classified into five main groups of acetylcholine esterase inhibitors, CNS stimulants, fampridine, herbal remedies, and miscellaneous. Overall heterogeneity of the studies was modest. The treatments did not affect cognitive function in any of the tasks (p>0.05). However, in subgroup analysis, we found significant improvement in SDMT task outecomes after treatment by fampridine (0.283 SMD, 95%CI, 0.015 to 0.550, p = 0.039, I2=11.7%). Our meta-analysis highlighted that the currently proposed therapeutic agents had no beneficial effects on the alleviation of MS-induced cognitive impairment.

Cognitive Fatigability is Independent of Subjective Cognitive Fatigue and Mood in Multiple Sclerosis

BACKGROUND

Sustained cognitive testing is used to detect cognitive fatigability and is often considered a substitute for subjective cognitive fatigue (CF). However, the relationship between cognitive fatigability and subjective CF in people with multiple sclerosis (PwMS) remains undetermined.

OBJECTIVE

To explore potential associations between fatigability induced by sustained cognitive testing and subjective CF in PwMS.

METHODS

We gave 120 PwMS and 60 demographically matched, healthy individuals the Beck Depression Inventory-FastScreen (BDI-FS) to measure mood and the Modified Fatigue Impact Scale to measure CF. In addition, we used the Quotient ADHD Test, a sustained attention test, to measure cognitive fatigability. We also explored potential correlations between the individuals' performance on the sustained attention test and thalamic volume using recent MRI scans.

RESULTS

Forty-one (34.2%) of the PwMS exhibited cognitive fatigability. These 41 were found to be significantly older (P=0.006), had been diagnosed with the disease for longer (P=0.03), had higher scores (P<0.001) on the Expanded Disability Status Scale, and had reduced thalamic volume (P=0.04) compared with the 79 (65.8%) PwMS not exhibiting cognitive fatigability. The PwMS exhibiting cognitive fatigability scored similarly on the BDI-FS (P=0.21) and self-reported similar rates of CF (P=0.62) as the PwMS not exhibiting cognitive fatigability.

CONCLUSION

Cognitive fatigability induced by sustained cognitive testing is not an accurate clinical alternative to subjective CF. This study provides evidence to support cognitive fatigability and CF in PwMS as two distinct concepts.

Cognitive Efficacy of Pharmacologic Treatments in Multiple Sclerosis: A Systematic Review

INTRODUCTION

Cognitive impairment is prevalent and debilitating among persons with multiple sclerosis (MS). While many pharmacologic treatments have shown good efficacy in reducing clinical relapses, brain lesions, and improving certain physical symptoms, their efficacy for improving cognitive function is not well understood.

OBJECTIVES

The current systematic review aimed to evaluate the efficacy of pharmacologic treatments for improving cognitive function among persons with MS.

METHODS

A literature search was conducted through the PubMed and PsycINFO databases. Two independent reviewers assessed each paper, and a third reviewer weighed in if the two reviewers could not reach a consensus. Classification of evidence was determined using the 2017 American Academy of Neurology (AAN) criteria for therapeutic trials. Standardized effect sizes (Cohen's d) were calculated to compare across studies.

RESULTS

Eighty-seven journal articles published between 1990 and January 2020 were included in the current review. Overall, there is insufficient evidence to support the use of pharmacologic treatments to improve cognitive function in persons with MS. There were many contradictory findings observed in this review, which may be due to possible unidentified moderating treatment response variables and/or lack of standardization in assessment procedures. There was also an overreliance on statistical significance (most papers did not provide sizes of treatment effects), which may not be clinically meaningful.

CONCLUSIONS

Higher-quality randomized controlled trials are needed to establish the cognitive efficacy of pharmacologic treatments for MS-related cognitive dysfunction, with cognition as the primary endpoint. Researchers are urged to use standardized criteria (such as the AAN criteria) to guide their research designs. Clinicians should consider effect sizes of studies before deciding whether to prescribe certain medications to ameliorate cognitive symptoms.

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.