An Open-Label, Prospective Study Evaluating the Clinical and Immunological Effects of Higher Dose Granulocyte Colony-Stimulating Factor in ALS.

OBJECTIVE: We evaluated the safety and tolerability of higher-dose granulocyte colony-stimulating factor (G-CSF) in patients with amyotrophic lateral sclerosis. In addition, rates of disease progression and serum G-CSF levels and other immunological and hematological markers were measured. METHODS: Three patients with advanced amyotrophic lateral sclerosis were treated with G-CSF subcutaneously at 5 µg/kg twice daily for 5 consecutive days monthly for 4-12 months. Patients were monitored for adverse effects, and disease progression was assessed with ALSFRS-R and other measures. RESULTS: Patients tolerated higher-dose G-CSF well with no serious adverse events. Adverse effects were mild to moderate with musculoskeletal pain and malaise being most often reported. No significant change in the rate of disease progression was noted for ALSFRS-R or other measures. Bone marrow progenitor cells were rapidly mobilized for a duration of approximately 9 days with transient and variable effect on cytokines. CONCLUSIONS: Higher-dose G-CSF was well tolerated in this cohort with no apparent effect on disease progression up to 1 year.

Clinical Effects of the Self-administered Subcutaneous Complement Inhibitor Zilucoplan in Patients With Moderate to Severe Generalized Myasthenia Gravis: Results of a Phase 2 Randomized, Double-Blind, Placebo-Controlled, Multicenter Clinical Trial.

Importance: Many patients with generalized myasthenia gravis (gMG) have substantial clinical disability, persistent disease burden, and adverse effects attributable to chronic immunosuppression. Therefore, there is a significant need for targeted, well-tolerated therapies with the potential to improve disease control and enhance quality of life. Objective: To evaluate the clinical effects of zilucoplan, a subcutaneously (SC) self-administered macrocyclic peptide inhibitor of complement component 5, in a broad population of patients with moderate to severe gMG. Design, Setting, and Participants: This randomized, double-blind, placebo-controlled phase 2 clinical trial at 25 study sites across North America recruited participants between December 2017 and August 2018. Fifty-seven patients were screened, of whom 12 did not meet inclusion criteria and 1 was lost to follow-up after randomization but before receiving study drug, resulting in a total of 44 acetylcholine receptor autoantibody (AChR-Ab)-positive patients with gMG with baseline Quantitative Myasthenia Gravis (QMG) scores of at least 12, regardless of treatment history. Interventions: Patients were randomized 1:1:1 to a daily SC self-injection of placebo, 0.1-mg/kg zilucoplan, or 0.3-mg/kg zilucoplan for 12 weeks. Main Outcomes and Measures: The primary and key secondary end points were the change from baseline to week 12 in QMG and MG Activities of Daily Living scores, respectively. Significance testing was prespecified at a 1-sided α of .10. Safety and tolerability were also assessed. Results: The study of 44 patients was well balanced across the 3 treatment arms with respect to key demographic and disease-specific variables. The mean age of patients across all 3 treatment groups ranged from 45.5 to 54.6 years and most patients were white (average proportions across 3 treatment groups: 78.6%-86.7%). Clinically meaningful and statistically significant improvements in primary and key secondary efficacy end points were observed. Zilucoplan at a dose of 0.3 mg/kg SC daily resulted in a mean reduction from baseline of 6.0 points in the QMG score (placebo-corrected change, -2.8; P = .05) and 3.4 points in the MG Activities of Daily Living score (placebo-corrected change, -2.3; P = .04). Clinically meaningful and statistically significant improvements were also observed in other secondary end points, the MG Composite and MG Quality-of-Life scores. Outcomes for the 0.1-mg/kg SC daily dose were also statistically significant but slower in onset and less pronounced than with the 0.3-mg/kg dose. Rescue therapy (intravenous immunoglobulin or plasma exchange) was required in 3 of 15, 1 of 15, and 0 of 14 participants in the placebo, 0.1-mg/kg zilucoplan, and 0.3-mg/kg zilucoplan arms, respectively. Zilucoplan was observed to have a favorable safety and tolerability profile. Conclusions and Relevance: Zilucoplan yielded rapid, meaningful, and sustained improvements over 12 weeks in a broad population of patients with moderate to severe AChR-Ab-positive gMG. Near-complete complement inhibition appeared superior to submaximal inhibition. The observed safety and tolerability profile of zilucoplan was favorable. Trial Registration: ClinicalTrials.gov Identifier: NCT03315130.

Long-term safety and efficacy of eculizumab in generalized myasthenia gravis.

INTRODUCTION: Eculizumab is effective and well tolerated in patients with antiacetylcholine receptor antibody-positive refractory generalized myasthenia gravis (gMG; REGAIN; NCT01997229). We report an interim analysis of an open-label extension of REGAIN, evaluating eculizumab's long-term safety and efficacy. METHODS: Eculizumab (1,200 mg every 2 weeks for 22.7 months [median]) was administered to 117 patients. RESULTS: The safety profile of eculizumab was consistent with REGAIN; no cases of meningococcal infection were reported during the interim analysis period. Myasthenia gravis exacerbation rate was reduced by 75% from the year before REGAIN (P < 0.0001). Improvements with eculizumab in activities of daily living, muscle strength, functional ability, and quality of life in REGAIN were maintained through 3 years; 56% of patients achieved minimal manifestations or pharmacological remission. Patients who had received placebo during REGAIN experienced rapid and sustained improvements during open-label eculizumab (P < 0.0001). DISCUSSION: These findings provide evidence for the long-term safety and sustained efficacy of eculizumab for refractory gMG. Muscle Nerve 2019.

Humoral factors in ALS patients during disease progression.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease affecting upper and lower motor neurons in the CNS and leading to paralysis and death. There are currently no effective treatments for ALS due to the complexity and heterogeneity of factors involved in motor neuron degeneration. A complex of interrelated effectors have been identified in ALS, yet systemic factors indicating and/or reflecting pathological disease developments are uncertain. The purpose of the study was to identify humoral effectors as potential biomarkers during disease progression. METHODS: Thirteen clinically definite ALS patients and seven non-neurological controls enrolled in the study. Peripheral blood samples were obtained from each ALS patient and control at two visits separated by 6 months. The Revised ALS Functional Rating Scale (ALSFRS-R) was used to evaluate overall ALS-patient functional status at each visit. Eleven humoral factors were analyzed in sera. Cytokine levels (GM-CSF, IL-1ß, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, and TNF-α) were determined using the Bio-Rad Bio-Plex® Luminex 200 multiplex assay system. Nitrite, a breakdown product of NO, was quantified using a Griess Reagent System. Glutathione (GSH) concentrations were measured using a Glutathione Fluorometric Assay Kit. RESULTS: ALS patients had ALSFRS-R scores of 30.5 ± 1.9 on their first visit and 27.3 ± 2.7 on the second visit, indicating slight disease progression. Serum multiplex cytokine panels revealed statistically significant changes in IL-2, IL-5, IL-6, and IL-8 levels in ALS patients depending on disease status at each visit. Nitrite serum levels trended upwards in ALS patients while serum GSH concentrations were drastically decreased in sera from ALS patients versus controls at both visits. CONCLUSIONS: Our results demonstrated a systemic pro-inflammatory state and impaired antioxidant system in ALS patients during disease progression. Increased levels of pro-inflammatory IL-6, IL-8, and nitrite and significantly decreased endogenous antioxidant GSH levels could identify these humoral constituents as systemic biomarkers for ALS. However, systemic changes in IL-2, IL-5, and IL-6 levels determined between visits in ALS patients might indicate adaptive immune system responses dependent on current disease stage. These novel findings, showing dynamic changes in humoral effectors during disease progression, could be important for development of an effective treatment for ALS.

Mitochondrial myopathy of childhood associated with mitochondrial DNA depletion and a homozygous mutation (T77M) in the TK2 gene.

BACKGROUND: The mitochondrial DNA depletion syndrome is an autosomal recessive disorder of infancy or childhood characterized by decreased mitochondrial DNA copy number in affected tissues. Mutations in 2 genes involved in deoxyribonucleotide metabolism, the deoxyguanosine kinase gene (DGK) and the thymidine kinase 2 gene (TK2), have been related to this syndrome. OBJECTIVE: To describe 3 siblings with the myopathic form of mitochondrial DNA depletion syndrome and a homozygous mutation in the TK2 gene. PATIENTS AND METHODS: These children developed normally until 12 to 16 months of age, when they started showing difficulty walking, which rapidly progressed to severe limb weakness. They died of respiratory failure between the ages of 23 and 40 months. Histochemical and biochemical studies of respiratory chain complexes were performed in muscle biopsy specimens. The whole coding region of the TK2 gene was sequenced. RESULTS: Muscle biopsy showed ragged-red cytochrome-c oxidase-negative fibers. All affected siblings had markedly decreased activities of respiratory chain complexes. Southern blot analysis showed severe reduction of the mitochondrial DNA-nuclear DNA ratio in muscle biopsy specimens from all patients, indicating 80% to 90% mitochondrial DNA depletion. Sequencing of the TK2 gene showed a homozygous C-->T transition at nucleotide 228 in exon 5, which changes a threonine to a methionine at position 77 (T77M). CONCLUSIONS: These results document the importance of screening the TK2 gene in patients with myopathic mitochondrial DNA depletion syndrome and confirm that exon 5 is a "hot spot" for TK2 mutations.

Mitochondrial diseases.

Since the first reports of disorders associated with mitochondrial DNA (mtDNA) defects more than a decade ago, the small mtDNA circle has been a Pandora's box of pathogenic mutations associated with human diseases. The "morbidity map" of mtDNA has gone from one point mutation and a few deletions in 1988 to more than 110 point mutations as of September, 2001. Nuclear DNA defects affecting mitochondrial function and mtDNA replication and integrity have also been identified in the past few years and more are expected. As a result, human "mitochondrial" diseases have evolved beyond the novelty diagnoses of a decade ago into an important area of medicine, and thus, the diagnostic principles of these disorders ought to be familiar to the clinician. In this article, the authors, we summarize the principles of mitochondrial genetics and discuss the common phenotypes, general diagnostic approach, and possible therapeutic venues for these fascinating disorders.