Faculty Bibliography

Ibudilast (MN-166) is an inhibitor of macrophage migration inhibitory factor (MIF) and phosphodiesterases 3,4,10 and 11 (Gibson et al., 2006; Cho et al., 2010). Ibudilast attenuates CNS microglial activation and secretion of pro-inflammatory cytokines (Fujimoto et al., 1999; Cho et al., 2010). In vitro evidence suggests that ibudilast is neuroprotective by suppressing neuronal cell death induced by microglial activation. People with ALS have increased microglial activation measured by [¹¹C]PBR28-PET in the motor cortices. The primary objective is to determine the impact of ibudilast on reducing glial activation and neuroaxonal loss in ALS, measured by PBR28-PET and serum Neurofilament light (NfL). The secondary objectives included determining safety and tolerability of ibudilast high dosage (up to 100 mg/day) over 36 weeks. In this open label trial, 35 eligible ALS participants underwent ibudilast treatment up to 100 mg/day for 36 weeks. Of these, 30 participants were enrolled in the main study cohort and were included in biomarker, safety and tolerability analyses. Five additional participants were enrolled in the expanded access arm, who did not meet imaging eligibility criteria and were included in the safety and tolerability analyses. The primary endpoints were median change from baseline in (a) PBR28-PET uptake in primary motor cortices, measured by standard uptake value ratio (SUVR) over 12-24 weeks and (b) serum NfL over 36-40 weeks. The secondary safety and tolerability endpoints were collected through Week 40. The baseline median (range) of PBR28-PET SUVR was 1.033 (0.847, 1.170) and NfL was 60.3 (33.1, 219.3) pg/ml. Participants who completed both pre and post-treatment scans had PBR28-PET SUVR median(range) change from baseline of 0.002 (-0.184, 0.156) , P = 0.5 (n = 22). The median(range) NfL change from baseline was 0.4 pg/ml (-1.8, 17.5), P = 0.2 (n = 10 participants). 30(86%) participants experienced at least one, possibly study drug related adverse event. 13(37%) participants could not tolerate 100 mg/day and underwent dose reduction to 60-80 mg/day and 11(31%) participants discontinued study drug early due to drug related adverse events. The study concludes that following treatment with ibudilast up to 100 mg/day in ALS participants, there were no significant reductions in (a) motor cortical glial activation measured by PBR28-PET SUVR over 12-24 weeks or (b) CNS neuroaxonal loss, measured by serum NfL over 36-40 weeks. Dose reductions and discontinuations due to treatment emergent adverse events were common at this dosage in ALS participants. Future pharmacokinetic and dose-finding studies of ibudilast would help better understand tolerability and target engagement in ALS.

BACKGROUND:Delayed-release dimethyl fumarate (DMF) has demonstrated robust efficacy in treating patients with relapsing-remitting multiple sclerosis. Decreases in absolute lymphocyte count (ALC) are a well-known pharmacodynamic effect of DMF treatment, but lymphocyte recovery dynamics are not well characterized after discontinuation of DMF. METHODS:Data sources included the Biogen DMF integrated clinical trial data set, a retrospective US chart abstraction study, and data from MSBase. We assessed rate and time course of lymphocyte reconstitution after DMF discontinuation. RESULTS:/L was 12-18 months vs 2-3 months in patients with lymphopenia persisting <6 months. CONCLUSIONS:The majority of patients who discontinued DMF due to lymphopenia experienced ALC reconstitution within 2-4 months following DMF discontinuation. This may help guide clinicians in managing patients who develop lymphopenia during DMF treatment. Prolonged lymphopenia on DMF treatment is associated with slow lymphocyte recovery after DMF discontinuation.

BACKGROUND:Computerized cognitive assessment facilitates the incorporation of multi-domain cognitive monitoring into routine clinical care. The predictive validity of computerized cognitive assessment among people with multiple sclerosis (PwMS) has scarcely been investigated. OBJECTIVE:To explore the associations between brain volumes and cognitive scores from a computerized cognitive assessment battery (CAB, NeuroTrax) among PwMS. METHODS:PwMS were evaluated with the CAB and underwent brain MRI within 40 days. Cognitive assessment yielded age- and education-adjusted scores in 9 cognitive domains: memory, executive function, attention, information processing speed, visual spatial, verbal function, motor skills, problem solving, and working memory. The global cognitive score (GCS) is the average of all domain scores. MRI brain and lesion volumes were assessed with icobrain ms, a fully automated tissue and lesion segmentation and quantification software. RESULTS:91 PwMS were included [Age: 52.1 ± 11.7 years, 64 (70%) female, EDSS: 3.4 ± 2.0, 79 (87%) with a relapsing remitting course]. Significant correlations were found between the GCS and whole brain, white matter, grey matter, thalamic, lateral ventricles, hippocampal and lesion volumes (Correlation coefficients: 0.46, 0.40, 0.25, 0.42, -0.36, 0.21, -0.3, respectively). Regression analysis revealed that lateral ventricles and thalamic volumes were the most consistent predictors of all cognitive domain scores. CONCLUSION:Computerized cognitive scores were significantly associated with quantified MRI. These findings support the predictive validity of multi-domain computerized cognitive assessment for people with multiple sclerosis.

BACKGROUND:Diroximel fumarate (DRF) is a novel oral fumarate for patients with relapsing-remitting multiple sclerosis (RRMS). DRF and the approved drug dimethyl fumarate yield bioequivalent exposure to the active metabolite monomethyl fumarate; thus, efficacy/safety profiles are expected to be similar. However, DRF's distinct chemical structure may result in a differentiated gastrointestinal (GI) tolerability profile. OBJECTIVE:To report interim safety/efficacy findings from patients in the ongoing EVOLVE-MS-1 study. METHODS:EVOLVE-MS-1 is an ongoing, open-label, 96-week, phase 3 study assessing DRF safety, tolerability, and efficacy in RRMS patients. Primary endpoint is safety and tolerability; efficacy endpoints are exploratory. RESULTS: < 0.0001) and adjusted annualized relapse rate was low (0.16; 95% confidence interval: 0.13-0.20). CONCLUSION:Interim data from EVOLVE-MS-1 suggest DRF is a well-tolerated treatment with a favorable safety/efficacy profile for patients with RRMS.

BACKGROUND:In patients treated with dimethyl fumarate, absolute lymphocyte count decline typically occurs during the first year and then plateaus; early drops have been associated with the development of severe prolonged lymphopenia. OBJECTIVE:We investigated the effect of dimethyl fumarate on absolute lymphocyte counts and CD4+/CD8+ T cells in patients with relapsing-remitting multiple sclerosis treated with dimethyl fumarate in routine practice. METHODS:Lymphocyte data were collected via medical chart abstraction. Primary endpoint: change from baseline in absolute lymphocyte count and CD4+/CD8+ counts at 6-month intervals following dimethyl fumarate initiation. RESULTS:/l) decreased by ∼39% (95% confidence interval: -41.1 to -37.2) by month 6 and 44% (95% confidence interval: -46.6 to -42.1) by month 12. CD4+ and CD8+ T-cell subsets strongly correlated with absolute lymphocyte count, with greater decreases from baseline to 6 months vs 6-12 months, and in CD8+ vs CD4+ T cells. Prior natalizumab was not a risk factor for lymphopenia. CONCLUSION/CONCLUSIONS:Dimethyl fumarate-associated decline in absolute lymphocyte count in the first 12 months correlated with decline in CD4+ and CD8+ T cells and was independent of prior natalizumab. Absolute lymphocyte count monitoring continues to be an effective strategy to identify patients at risk of prolonged lymphopenia.

Multiple sclerosis (MS) is a chronic inflammatory and demyelinating disease of the central nervous system. The disease affects more women than men and often is diagnosed during a woman's childbearing years. Typical clinical presentations of the disease are extensive and variable, with symptoms that include dysregulated mood, fatigue, vision problems, weakness, tremor, imbalance, abnormal sensations, bladder dysfunction, and heat sensitivity. If a woman aged 15-50 years experiences these neurologic symptoms in isolation or combination, and the symptoms are not explained by other underlying medical conditions, MS should be suspected. Multiple sclerosis can be divided into four clinical subtypes: 1) relapsing-remitting MS, 2) secondary progressive MS, 3) primary progressive MS, and 4) clinically isolated syndrome. Relapsing-remitting MS at the time of onset is the most common form and accounts for approximately 80% of all cases of MS. Relapsing-remitting MS does not affect life expectancy. However, because of the neurodegenerative and progressive course of the disease, patients accumulate physical and cognitive disabilities over time that result in impaired ability to work, increased financial burden, and slightly increased mortality. A variety of possible risk and prognostic indicators have been identified that may predict the course of disease, particularly the extent of relapses and disability. Multiple sclerosis currently is incurable, but many disease-modifying therapies are available that can reduce the frequency of clinically evident exacerbations and accumulation of disease burden as defined by the number of lesions identified on magnetic resonance imaging. The choice of disease-modifying therapies, contraception use, and treatment of symptoms should be individualized based on age at onset and disease activity and, during pregnancy, the gestational age. Proactive management of MS across the woman's life cycle reduces morbidity, improves maternal and fetal health during pregnancy and the postpartum period, and increases quality-of life-measures for patients and their families.