Background

Masitinib (MAS) is a small molecule drug targeting KIT, LYN and CSF1R. Proof-of-concept that MAS slows progressive multiple sclerosis (MS) was previously demonstrated.

Objectives

Assessment of oral MAS as a treatment for progressive MS. Study AB07002 (NCT01433497) evaluated 2 independent parallel groups; 4.5 mg/kg/d vs matched placebo (PBO), and titrated MAS dose of 6.0 mg/kg/d vs PBO.

Methods

Randomized (2:1), double-blinded, placebo-controlled, 2-parallel group trial. Eligible patients (pts) aged 18­–75 years, with baseline Expanded Disability Status Scale (EDSS) 2.0–6.0, regardless of time-from-onset, and diagnosed with primary progressive (PPMS) or non-active secondary progressive (nSPMS) MS, were treated for 96 weeks. Primary endpoint was overall EDSS change from baseline using repeated measures (GEE model, timeframe W12–W96, measured every 12 weeks). Results are expressed as least-squares means difference (δEDSS, positive value indicates worsening), with treatment-effect reported as between-group difference (ΔLSM, negative value favors MAS). A key sensitivity analysis was the 3-level ordinal EDSS model (±1 or 0, repeated measures), which simultaneously measures improved, stable, or worsening outcomes over duration of treatment.

Results

MAS (4.5mg/kg/d) (n=199, median EDSS=5.5, mean age=49.3±9.6 years) showed significant benefit over PBO (n=101) with δEDSS of 0.001 vs 0.098, respectively, and ΔLSM of -0.097(95%CI[-0.192,-0.002]);p=0.0256. This treatment-effect was numerically maintained for the subgroups of nSPMS (MAS n=120 vs 56) and PPMS (MAS n=79 vs 45) with ΔLSM of -0.104(95%CI[-0.198,-0.008]; p=0.032) and -0.128(95%CI [-0.285,0.0282];p=0.108), respectively. All EDSS sensitivity analyses were convergent with the primary outcome, including the conservative jump-to-reference approach with ΔLSM of -0.089 (95%CI[-0.173,-0.006];p=0.0367). Ordinal EDSS analysis showed a significant 39% relative probability of either reduction in EDSS progression or increase in EDSS improvement (hazard ratio (HR) 0.610 (95%CI[0.376,0.988];p=0·0446). Analysis of EDSS time-to-progression showed a significant reduced relative risk of 42% with MAS for first progression (HR 0.58, 95%CI[0.35,0.96];p=0.034), and a reduced relative risk of 37% with MAS for 12-week confirmed (HR 0.63, 95%CI[0.33,1.20];p=0.159). The proportion of pts presenting at least one adverse event (AE) was 94.5% for MAS (4.5 mg/kg/d) vs 87.1% for PBO. Safety was consistent with the known profile for MAS, common treatment-emergent AEs being diarrhea, nausea, rash, and hematological assessments. Efficacy results from the MAS high-dose parallel group (titrated 6.0 mg/kg/d) were inconclusive and no new safety signal was observed.

Conclusions

MAS (4.5 mg/kg/d), a first-in-class TKI targeting the innate immune system via inhibition of mast cell and microglia/macrophage activity, may provide a new treatment option for PPMS and nSPMS

Background

There is limited evidence on the effects of disease modifying therapies (DMTs) on MS symptoms, health-related quality of life (HRQoL) and employment outcomes, particularly the comparative effectiveness between different available DMTs.

Objectives

By using the prospectively collected patient-reported data in the Australian MS Longitudinal Study (AMSLS) from 2015 to 2017, we aimed to compare natalizumab to other DMTs in relation to employment outcomes, MS symptom severity, HRQoL, and progression in the previous 12 months.

Methods

Medication and Disease Course surveys were conducted in 2015, 2016 and 2017, and collected data on DMTs, severity of 13 MS symptoms (0-10 scale), disability, HRQoL by European Quality of Life with five dimensions (EQ-5D) and work productivity loss (absenteeism, presenteeism, total work productivity loss in the previous 4 weeks). We used marginal structural models to estimate causal effect of natalizumab versus other DMT comparators (any other DMT, classic injectables, oral therapies (teriflunomide and dimethyl fumarate), higher efficacy DMTs (fingolimod, alemtuzumab and mitoxantrone), fingolimod, and alemtuzumab), while adjusting for time-varying confounders and intermediates of treatment effects.

Results

The analysis included 2836 observations. Compared to any other DMTs, natalizumab was associated with superior effects over time on improving balance, vision symptoms, sensory symptoms, bladder symptoms, sexual dysfunction, and feelings of anxiety. The strongest effect was seen for improving sensory problems (mean coefficient -0.44 (-0.66 to -0.22) per year). There was no evidence of an effect of natalizumab over time on improving HRQoL measured by the EQ-5D, but use of any other DMTs were associated with a significant decrease in EQ-5D. The use of natalizumab was associated with a marginal decrease in self-reported progression in the previous 12 months while the use of injectable DMTs and fingolimod were associated with an increased self-reported progression. The use of natalizumab was associated with a reduction in work productivity loss due to absenteeism compared to a worsening for any other DMT, and similar trends were less pronounced for presenteeism and total work productivity loss.

Conclusions

Compared to other DMTs, the use of natalizumab was associated with superior effects over time for several MS symptoms and absenteeism.

Background

Glial fibrillary acidic protein (GFAP) is released into the cerebrospinal fluid and blood upon astroglial injury and activation, one of the hallmarks of progressive multiple sclerosis (PMS). It is unclear whether blood GFAP levels are associated with disability accumulation in secondary progressive MS (SPMS).

Objectives

To explore GFAP as a prognostic biomarker of disability worsening in patients with active and/or non-active SPMS (aSPMS and/or naSPMS) in the Phase 3 EXPAND study.

Methods

In this post-hoc analysis from the EXPAND study, baseline (BL) GFAP was quantified in EDTA plasma samples using Single Molecule Array technology. GFAP was categorized as high/low based on the gender stratified 80 percentile. The effect of GFAP on time to Expanded Disability Status Scale [EDSS] 7 (wheelchair restricted) was assessed using a Cox regression model adjusted for age, gender, disease duration, treatment, relapses in the 24 months prior to study start, and BL EDSS. Subgroup analyses were conducted in patients with aSPMS/naSPMS (with/without relapses ≤24 months prior to study entry, and/or gadolinium-enhancing T1 lesions at BL) and were also stratified by gender.

Results

Samples were available for 1405 of the 1651 patients randomized in the EXPAND study; median GFAP levels (pg/mL) were 119.6 (male) and 141.4 (female). Overall, the risk of reaching EDSS 7 was higher in patients with high BL GFAP (96%: high vs low GFAP, [34/281, 12.1%] vs [54/1117, 4.8%]; HR 1.96 [1.27; 3.03]; p=0.0024). Interestingly, the increased risk of reaching EDSS 7 was mainly seen in females (23/169; 13.6%] vs [34/673; 5.1%]; HR 2.22 [1.30; 3.80]; p=0.0035), and not significant in males ([11/112, 9.8%] vs [20/444, 4.5%]; HR 1.45 [0.67; 3.12]; p=0.3457). Increase in risk of reaching EDSS 7 was mainly observed in naSPMS patients (high GFAP [14/133; 10.5%] vs low GFAP [22/570; 3.9%]; HR 3.40 [1.71; 6.75]; p=0.0005) and was not significant in aSPMS patients (high GFAP [20/144; 13.9%] vs low GFAP [30/521; 5.8%]; HR 1.58 [0.88; 2.82]; p=0.1250). However, associations between BL GFAP levels and time to 6-months confirmed disability progression showed similar trends, but were less pronounced.

Conclusions

Blood GFAP appears to be a prognostic biomarker of disability worsening. The relevance of the gender difference and the stronger correlations found in SPMS patients with non-active versus active disease needs further investigation.

Background

Respiratory disorders (RD) remain incompletely described and understood in multiple sclerosis (MS), although they might play an important role in the burden of MS. RD are the first cause of mortality in MS patients, and could suddenly worsen with acute respiratory failure, for example during an infectious pneumopathy. However, they are underestimated especially due to the motor disability and cognitive disorders.

Objectives

The primary objective was to assess the categories of RD in MS patients:

i) isolated respiratory muscles impairment (decrease of inspiratory maximal pressure or sniff nasal inspiratory pressure < 60%)

ii) diaphragmatic dysfunction (upright vital capacity (VC) - supine VC > 20% of upright VC and/or phasic activation of respiratory muscles during sleep and/or opposition of the thoracic and abdominal respiratory movements during sleep and/or orthopnea and/or respiratory muscles impairment )

iii) nocturne alveolar hypoventilation (PaCO2 > 45 mmHg and/or during the sleep : > 10 min of sleep with PtcCO2 > 55 mmHg or PaCO2 > 50 mmHg if increasing of PaCO2 > 10 mmHg between awake and the sleep).

The secondary objectives were to evaluate the correlation between RD and i) disability scores, including fatigue and cognitive evaluation, and ii) MRI encephalic and spinal lesion load.

Methods

Patients with severe MS (EDSS ≥ 6.5), with or without respiratory complaint, were included in this prospective monocentric study. Comprehensive pulmonary function tests, polysomnography with specific electromyography of accessory respiratory muscles, cognitive tests, brain and cervical spinal cord MRI were performed within 24 hours.

Results

71 patients (39 F/32 M) were included: median age 53,9 years (IQR: 48.40-60.95), median EDSS 7.5 (IQR: 6.5 - 8), median disease duration 21.4 years (IQR: 16-31.35). 46 patients (65%) had diaphragmatic dysfunction, including 36 patients (50%) with isolated respiratory muscles impairment. 9 patients (13%) had nocturnal alveolar hypoventilation. 21 (30 %) patients had no RD. Correlation studies with disability scores and MRI lesion load are on going.

Conclusions

Using specific technics of polysomnography and respiratory muscle testing, this study highlights the frequency of respiratory disorders in MS patients with EDSS ≥ 6.5, but also provides innovative insight into the different types of RD. These findings should lead to specific multidisciplinary care, such as non-invasive ventilation or preventive measures (vaccination against pulmonary infections for patients and families).

Background

Obesity is increasingly recognized as a risk for multiple sclerosis (MS). While the underlying mechanisms remain undetermined, reduced vitamin D bioavailability and altered levels of the immunomodulatory cytokines adiponectin and leptin have been proposed.

Objectives

To determine the roles of vitamin D, adiponectin and leptin levels in explaining the effect of obesity on MS, using a Mendelian randomization (MR) mediation framework.

Methods

Independent genetic estimates for body mass index (BMI), 25-hydroxyvitamin D (25OHD), adiponectin and leptin levels were obtained from from large-scale genome-wide association studies and the UK Biobank, totalling over 800,000 participants. The effect on MS was measured using summary genetic data on 14,802 MS cases and 26,703 controls from the International MS Genetics Consortium (IMSGC). To avoid bias from population stratification, all participants were of European ancestry. We estimated the odds of MS for each of the exposures, and the proportion of the effect of BMI explained by potential mediators significantly associated with MS, using the product of coefficients method in a two-step MR framework.

Results

Each standard deviation (SD) increase in BMI was associated with a 40% increase in the odds of MS (95% CI 1.16 to 1.67, P=3.1x10^-4). Similarly, a SD increase in standardized log transformed 25OHD levels reduced the odds of MS by 28% (95% CI 0.60-0.87, P=6.2x10^-4). In contrast, we observed no notable effect of adiponectin (OR=1.05, 95% CI 0.74-1.49, P=0.78) or leptin (OR=1.18, 95% CI 0.59-2.36, P=0.64) on the odds of MS. In MR mediation analysis, we estimate that the reduction in 25OHD levels only explains 5.4% of the effect of increased BMI on the risk of MS (95% CI 0.4% to 30.5%). Sensitivity analyses showed that these estimates were robust to potential bias from pleiotropy.

Conclusions

This study found that only a minority of the increased risk of MS conferred by obesity is mediated by lowered vitamin D levels, while leptin and adiponectin had no measurable effect. This suggests that vitamin D supplementation would only modestly reverse the effect of obesity on MS, the majority of which remains unexplained.