Background and Aims:

Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease. Underlying genetic pathomechanisms include the C9orf72 repeat expansion, the most frequent genetic cause of ALS (C9ALS) in Western countries. Despite recent progress in unraveling C9ALS pathogenesis, reliable disease models and disease-modifying therapies still lack. Here, we aim to model C9ALS in vitro using 3D human spinal cord organoids (SCOs).

Methods:

We differentiated C9ALS induced pluripotent stem cells (iPSCs) and isogenic controls using a free-floating 3D-culture method. We generated SCOs with a modified Lancaster’s protocol promoting neural caudalization and ventralization. Then, we treated C9ALS SCOs with morpholino antisense oligonucleotides (MO) against C9Orf72 repeat expansion. Finally, we assessed the differentiation of organoids at different time points with morphological, immunohistochemical, and qPCR analysis.

Results:

We generated isogenic and C9ALS SCOs exhibiting different co-existing neuronal subpopulations. SCOs expressed neural progenitor, pan-neuronal, astrocyte, motor neuron, and rostrocaudal markers, including markers of cervicobrachial spinal cells. Compared to controls, C9ALS early SCOs diameters measured from day 2 to day 13 were significantly reduced. C9ALS organoids displayed increased dipeptide repeat proteins (DPRs) levels, DNA damage markers associated with C9orf72 expansion, and cytoplasmic inclusions of translocated TDP-43, C9ALS-specific disease hallmarks. Gene expression analysis using qPCR reported differential expression of genes associated with DNA damage and motor neurons in MO-treated C9ALS organoids.

Conclusions:

SCOs represent a valuable system for modeling features of C9ALS pathology, investigating C9ALS pathomechanisms, and testing possible new treatments in vitro.

Background and Aims:

The impaired bulbar function represents the main source of disability in patients affected by amyotrophic lateral sclerosis (ALS). We investigated whether differences in medulla oblongata volumes may predict survival in an ALS cohort.

Methods:

Demographic and clinical data were recorded in 80 ALS patients from diagnosis to tracheostomy/death or censoring-date. At the time of diagnosis, patients underwent a 3D-T1 MRI. Medulla Oblongata (MO) volume was calculated by Freesurfer and FSL. The whole cohort was divided into lower and higher MO volume groups (L-MOV and H-MOV, respectively) according to the best value of MO volume by ROC curve able to discriminate short from long survivors, using median survival time as a cut-off. Univariate and multivariate survival analyses were performed using as covariates the L-MOV and H-MOV groups, gender, age, and site of onset.

Results:

The L-MOV group was characterized prevalently by patients with older age of onset, female gender, and a higher progression rate (Figure). The survival was significantly reduced in the L-MOV group (log-rank, p<0.0001). In multivariate analysis, L-MOV was the only variable significantly associated with survival [HR: 3.71; 95%CI: 2-6.9;p<0.001].

Conclusions:

Our findings show that the medulla oblongata atrophy itself represents the critical “epicenter” of the poor clinical outcome of ALS patients regardless of the site of onset. Therefore, this measure may be considered an attractive candidate biomarker predictive of survival in ALS.

Background and Aims:

C9orf72 mutation carriers with different neurological phenotypes, also in pre-symptomatic phases, show cortical atrophy in multiple different brain regions. Besides cortical thinning, also subcortical structureshave been found to be altered, both in C9orf72 carriers and in wild-type patients.

The aim of this study is to assess cortical and subcortical alterations in a large sample of mutation carriers and matched wild-type ALS patients.

Methods:

We paired 24 C9orf72 positive (C9orf72+) ALS patients with 24 C9orf72 negative (C9orf72-) ALS patients. They underwent 1.5T MRI assessment, performing 3D T1-weighted image scans. Vertex-wise between-group analyses for cortical thickness and subcortical region shape was performed to assess significant differences between C9orf72+ and C9orf72- groups.

Results:

The cortical vertex-wise showed a reduced cortical thickness in C9orf72+ patients in extended regions of the brain, in particular in: bilateral precentral and postcentral cortex, superior frontal gyrus, and precuneus, in left inferior temporal cortex, fusiform and parahippocampal gyri, lateral and medial orbital frontal cortex, posterior and rostral anterior cingulate, in right superior parietal and supramarginal cortex.

The subcortical vertex-wise showed an extensive reduced volume in C9orf72+ patients in bilateral thalamus, in bilateral caudate, and left putamen. On the other side, C9orf72- patients, in comparison to C9orf72+ patients, showed a selective reduction of volume in the anterior portion of left amygdala.

Conclusions:

Extensive brain atrophy is present in C9orf72+ patients when compared to C9orf72- patients with similar disease burden. Different extra-motor cortical regions and subcortical structures, such as the amygdala, could play a different role in ALS patients.

Background and Aims:

Efgartigimod, a human IgG1 antibody Fc-fragment, blocks the neonatal Fc receptor, which decreases recycling of IgG and reduces pathogenic autoantibody levels. In a phase 2 study, it demonstrated efficacy and was well tolerated in patients with generalized myasthenia gravis (gMG), an IgG antibody-mediated disease.

Methods:

ADAPT was a phase 3, randomized, double-blind, placebo controlled, global, multicenter 26-week study that evaluated the safety and efficacy of efgartigimod in patients with gMG. Participants were randomized 1:1 to receive four weekly 10 mg/kg infusions of efgartigimod or placebo with subsequent treatment cycles administered according to clinical response.

Results:

167 (129 AChR-Ab+ and 38 AChR-Ab-) patients were randomized. Significantly more patients treated with efgartigimod, compared to placebo, achieved sustained statistically and clinically significant improvement in both MG-ADL and QMG scores. The majority of adverse events (AEs) were mild or moderate. Infections were of special interest and occurred with similar frequency in efgartigimod and placebo treated patients (46.4% and 37.3%, respectively). The type and severity of infections were similar between groups, with no serious or opportunistic infections in the efgartigimod group. Headache was the most common AE (efgartigimod: 28.6%, placebo: 27.7%), but none were serious or required treatment interruption. Most patients experienced headache only once. Infusion related reactions were infrequent, despite the absence of premedication, occurring in 3.6% of efgartigimod and 9.6% of placebo patients, none were serious or required a change in efgartigimod dose and no hypersensitivity or anaphylactic reactions were reported.

Conclusions:

Efgartigimod was not only clinically efficacious, but also well tolerated in patients with gMG.

Background and Aims:

The International Centre for Genomic Medicine in Neuromuscular Diseases (ICGNMD) is a £5m, 5 year MRC Strategic award whose goal is to improve health outcomes for people with neuromuscular diseases (NMDs) globally. Activity is distributed across 14 Centres in Brazil, India, Turkey, South Africa, the United Kingdom and Zambia.

The ICGNMD aims to:

• deliver an international genomics research & capacity-building partnership in genomic medicine;

• facilitate international NMD patient access to accurate genetic diagnoses;

• assemble "trial ready" comprehensively phenotyped and genotyped cohorts of people living with NMDs and their families; and

growing clinical capacity in neuromuscular diseases by training a cohort of clinical academic researchers

Methods:

ICGNMD participants are consented at local centres. Details are entered into a secure REDCap ICGNMD database, with emphasis on use of HPO terms. Samples are analysed either locally or at University College London. Cross-site meetings determine the genetic testing strategy for each participant. Results are reviewed at cross-site MDT-style meetings. After a period of protected time for local analysis and capacity-building activity, data will be made available to the wider research community.

Results:

As of March 2021 1509 participants had been recruited. (South Africa 15%, India 50%, Brazil 15%, Turkey 20%, Zambia <1%).

Conclusions:

ICGNMD will deliver long-term clinical-academic research partnerships and engage with policy-makers and pharma to support equitable access to emerging treatments for patients with neuromuscular diseases. The project will serve as a resource for the international community for solving undiagnosed neuromuscular disease with an emphasis on understudied populations and understanding neuromuscular phenotypes in these groups.

Background and Aims:

Hereditary transthyretin-mediated (hATTR) amyloidosis, is a progressive, life-threatening disease. Patisiran’s efficacy/safety have been demonstrated in Phase 2 and 3 studies in patients with hATTR amyloidosis with polyneuropathy. Interim 24-month efficacy/safety analyses of the ongoing Global OLE study are described.

Methods:

Multicenter, international, OLE, safety/efficacy study (NCT02510261) in patients who completed parent studies, including patients in the Phase 3 APOLLO randomized to placebo (n=49) or patisiran (n=137) over 18 months and patients in the Phase 2 OLE (n=25) receiving patisiran over 24 months.

Results:

178/211 patients enrolled in the Global OLE had at least 24 months of exposure as of October 7, 2019. Safety profile remained consistent with previous studies. After 24 months of additional patisiran treatment, durable improvement was seen for mNIS+7 (mean change [­SEM]) in APOLLO/patisiran (-4.9 [2.1]) and Phase 2 OLE (-5.9 [2.1]) groups compared to their parent study baselines. Norfolk QOL-DN continued to show durable improvement in APOLLO/patisiran patients (-2.4 [2.4]). APOLLO/placebo patients experienced halting of disease progression and QOL improvement compared to Global OLE baseline after 24 months of patisiran (mNIS+7: +0.1 [3.3], Norfolk QOL-DN: -4.1 [3.3]), although they had progressed relative to APOLLO baseline (mNIS+7: +26.3 [5.0], Norfolk QOL-DN: +15.8 [4.5]) given the progression while on placebo.

Conclusions:

In the Global OLE, patisiran continue to demonstrate long-term durable efficacy. Despite marked progression on placebo during APOLLO, previously untreated patients continue to exhibit halting of disease progression and QOL improvement following 24 months of patisiran. Patisiran continues to demonstrate a positive benefit:risk profile.

Background and Aims:

Hereditary transthyretin-mediated (hATTR) amyloidosis, also known as ATTRv amyloidosis, is a progressive disease caused by misfolded transthyretin (TTR) that accumulates as amyloid fibrils in multiple tissues and organs. Vutrisiran, an investigational RNAi therapeutic for the treatment of ATTR amyloidosis, targets variant and wild-type TTR.

Methods:

HELIOS-A (NCT03759379) is a Phase 3, global, open-label study of vutrisiran 25 mg SC every 3 months in patients with ATTRv amyloidosis with polyneuropathy,randomized (3:1) to vutrisiran or patisiran, a reference comparator RNAi therapeutic approved for hATTR amyloidosis with polyneuropathy. Randomization was stratified by TTR genotype (V30M vs. non-V30M) and baseline NIS score (<50 vs ≥50). The APOLLO placebo arm (N=77) serves as external control for the primary and most secondary endpoints. Month 9 efficacy analyses include change from baseline in mNIS+7 (primary endpoint), Norfolk QOL-DN (secondary), and 10-meter walk test (10-MWT) (secondary), compared to APOLLO placebo arm.

Results:

HELIOS-A enrolled 164 patients (122 [74.4%] vutrisiran, 42 [25.6%] patisiran). Vutrisiran met the primary endpoint (p<0.001) and achieved statistical significance (p<0.001) for all planned secondary endpoints. The majority of patients showed improvement in neurologic impairment and quality of life relative to baseline. Vutrisiran demonstrated an acceptable safety profile; most common adverse events in vutrisiran-treated patients occurred at similar or lower rate versus the APOLLO placebo arm.

Conclusions:

The 9-month primary analysis demonstrates that vutrisiran improves neuropathy and QOL in patients with ATTRv amyloidosis with polyneuropathy. HELIOS-A will continue to investigate the efficacy and safety of vutrisiran through the 18-month treatment and extension periods.

Background and Aims:

The diagnosis of Guillain Barre Syndrome and Chronic Inflammatory Demyelinating Polyneuropathy depends on an appropriate history, examination, CSF cyto-protein dissociation and abnormal peripheral nerve conduction studies (PNCS). We present two cases suggestive of GBS but with repeatedly normal PNCS, a paradoxical phenomenon.

Methods:

Case 1

A 23-year-old girl presented with acute limb “weakness” with areflexia. PNCS done later than a week after the onset was completely normal including unaltered ‘F’ waves. CSF protein was high (67mg/dl). She was recoverd with Intravenous Immunoglobulin (IVIG) and managed to walk independently, but quadriparesis relapsed after 3weeks. A treatment related fluctuation (TRF) was suspected. Repeat CSF studies showed markedly raised protein (400mg/dl) with no cells. She was still areflexic. Repeat PNCS including ‘F’ waves too was normal. Plasma exchange therapy was initiated.

Case 2

A 20-year-old female treated as GBS a year ago presented with acute onset limb weakness with ataxia. Examination revealed predominantly proximal “weakness” and areflexia. CSF shows raised protein at 70mg/dl. PNCS several studies on both occasions are completely normal. Patient improved with IVIG.

Results:

somatosensory evoked potentials (SSEP), motor evoked potential (MEP) and imaging is warranted.

Conclusions:

Above patients clinically fits into GBS with TRF and possible recurrent GBS. However, PNCS are normal in the both throughout their illnesses; unexpected phenomenon. It is possible that they both have a form of CIDP which is confined to the nerve roots proximal to ganglions; Chronic Inflammatory Sensory Polyradiculopathy (CISP). Further evaluation with somatosensory evoked potentials (SSEP), motor evoked potential (MEP) and imaging is warranted.