Clemastine fumarate as a remyelinating therapy for multiple sclerosis (ReBUILD): a randomised, controlled, double-blind, crossover trial.

BACKGROUND: Multiple sclerosis is a degenerative inflammatory disease of the CNS characterised by immune-mediated destruction of myelin and progressive neuroaxonal loss. Myelin in the CNS is a specialised extension of the oligodendrocyte plasma membrane and clemastine fumarate can stimulate differentiation of oligodendrocyte precursor cells in vitro, in animal models, and in human cells. We aimed to analyse the efficacy and safety of clemastine fumarate as a treatment for patients with multiple sclerosis. METHODS: We did this single-centre, 150-day, double-blind, randomised, placebo-controlled, crossover trial (ReBUILD) in patients with relapsing multiple sclerosis with chronic demyelinating optic neuropathy on stable immunomodulatory therapy. Patients who fulfilled international panel criteria for diagnosis with disease duration of less than 15 years were eligible. Patients were randomly assigned (1:1) via block randomisation using a random number generator to receive either clemastine fumarate (5·36 mg orally twice daily) for 90 days followed by placebo for 60 days (group 1), or placebo for 90 days followed by clemastine fumarate (5·36 mg orally twice daily) for 60 days (group 2). The primary outcome was shortening of P100 latency delay on full-field, pattern-reversal, visual-evoked potentials. We analysed by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT02040298. FINDINGS: Between Jan 1, 2014, and April 11, 2015, we randomly assigned 50 patients to group 1 (n=25) or group 2 (n=25). All patients completed the study. The primary efficacy endpoint was met with clemastine fumarate treatment, which reduced the latency delay by 1·7 ms/eye (95% CI 0·5-2·9; p=0·0048) when analysing the trial as a crossover. Clemastine fumarate treatment was associated with fatigue, but no serious adverse events were reported. INTERPRETATION: To our knowledge, this is the first randomised controlled trial to document efficacy of a remyelinating drug for the treatment of chronic demyelinating injury in multiple sclerosis. Our findings suggest that myelin repair can be achieved even following prolonged damage. FUNDING: University of California, San Francisco and the Rachleff Family.

Timing of retinal neuronal and axonal loss in MS: a longitudinal OCT study.

The objective of the study was to investigate the timing of central nervous system tissue atrophy in MS by evaluating longitudinal retinal volume changes in a broadly representative cohort with disease duration across the entire arc of disease. In this longitudinal study, 135 patients with MS and 16 healthy reference subjects underwent spectral-domain optical coherence tomography (OCT) at baseline and 2 years later. Following OCT quality control, automated segmentation of the peripapillary retinal nerve fiber layer (pRNFL), macular ganglion cell-inner plexiform layer (mGCIPL) and macular inner nuclear layer (mINL) was performed. Generalized estimation equations were used to analyze longitudinal changes and associations with disease duration and clinical measures. Participants had a median disease duration at baseline of 16.4 years (range 0.1-45.4). Nearly half (44 %) of the MS patients had previously experienced MS-related optic neuritis (MSON) more than 6 months prior. The MS patients demonstrated a significant decrease over 2 years of the pRNFL (-1.1 µm, 95 % CI 1.4-0.7, p < 0.001) and mGCIPL (-1.1 µm, 95 % CI -1.4 to -0.8, p < 0.001). This thinning was most pronounced early in the course of disease. These findings were irrespective of previous episodes of MSON. No consistent pattern of change was observed for the mINL (-0.03 µm, 95 % CI -0.2 to 0.2, p = 0.795). This longitudinal study demonstrated that injury of the innermost retinal layers is found in MS and that this damage occurs most rapidly during the early stages of disease. The attenuation of atrophy with longer disease duration is suggestive of a plateau effect. These findings emphasize the importance of early intervention to prevent such injury.

Retinal thickness measured with optical coherence tomography and risk of disability worsening in multiple sclerosis: a cohort study.

BACKGROUND: Most patients with multiple sclerosis without previous optic neuritis have thinner retinal layers than healthy controls. We assessed the role of peripapillary retinal nerve fibre layer (pRNFL) thickness and macular volume in eyes with no history of optic neuritis as a biomarker of disability worsening in a cohort of patients with multiple sclerosis who had at least one eye without optic neuritis available. METHODS: In this multicentre, cohort study, we collected data about patients (age ≥16 years old) with clinically isolated syndrome, relapsing-remitting multiple sclerosis, and progressive multiple sclerosis. Patients were recruited from centres in Spain, Italy, France, Germany, Czech Republic, Netherlands, Canada, and the USA, with the first cohort starting in 2008 and the latest cohort starting in 2013. We assessed disability worsening using the Expanded Disability Status Scale (EDSS). The pRNFL thickness and macular volume were assessed once at study entry (baseline) by optical coherence tomography (OCT) and was calculated as the mean value of both eyes without optic neuritis for patients without a history of optic neuritis or the value of the non-optic neuritis eye for patients with previous unilateral optic neuritis. Researchers who did the OCT at baseline were masked to EDSS results and the researchers assessing disability with EDSS were masked to OCT results. We estimated the association of pRNFL thickness or macular volume at baseline in eyes without optic neuritis with the risk of subsequent disability worsening by use of proportional hazards models that included OCT metrics and age, disease duration, disability, presence of previous unilateral optic neuritis, and use of disease-modifying therapies as covariates. FINDINGS: 879 patients with clinically isolated syndrome (n=74), relapsing-remitting multiple sclerosis (n=664), or progressive multiple sclerosis (n=141) were included in the primary analyses. Disability worsening occurred in 252 (29%) of 879 patients with multiple sclerosis after a median follow-up of 2·0 years (range 0·5-5 years). Patients with a pRNFL of less than or equal to 87 µm or less than or equal to 88 µm (measured with Spectralis or Cirrus OCT devices) had double the risk of disability worsening at any time after the first and up to the third years of follow-up (hazard ratio 2·06, 95% CI 1·36-3·11; p=0·001), and the risk was increased by nearly four times after the third and up to the fifth years of follow-up (3·81, 1·63-8·91; p=0·002). We did not identify meaningful associations for macular volume. INTERPRETATION: Our results provide evidence of the usefulness of monitoring pRNFL thickness by OCT for prediction of the risk of disability worsening with time in patients with multiple sclerosis. FUNDING: Instituto de Salud Carlos III.

Microcystic inner nuclear layer abnormalities and neuromyelitis optica.

IMPORTANCE: Microcystic abnormalities involving the inner nuclear layer of the retina occurs in a subset of patients with multiple sclerosis, most commonly in eyes previously affected by symptomatic optic neuritis. Acute optic neuritis is a cardinal manifestation of neuromyelitis optica (NMO). To our knowledge, microcystic inner nuclear layer abnormalities have not been investigated in NMO. OBJECTIVE: To establish whether microcystic inner nuclear layer abnormalities occur in NMO. DESIGN: Observational, retrospective study. SETTING: University of California at San Francisco Multiple Sclerosis Center (academic specialty clinic). PATIENTS: Twenty-five consecutive patients with NMO based on 2006 diagnostic criteria or with NMO spectrum disease (defined by seropositivity for anti-aquaporin 4 IgG in the context of a single episode of transverse myelitis or optic neuritis). EXPOSURE: Spectral-domain optical coherence tomography. MAIN OUTCOMES AND MEASURES: Identification of microcystic inner nuclear layer pathology on spectral-domain optical coherence tomography. Multivariable linear regression was used to examine associations between microcystic changes and measures of retinal structure and function. The hypothesis was generated prior to the data being reviewed and analyzed. RESULTS: Microcystic changes were identified in 5 of 25 patients with NMO (20%) and 7 of 48 total eyes, including 7 of 29 eyes (24%) previously affected by optic neuritis. Microcystic changes occurred exclusively in eyes with a history of acute symptomatic optic neuritis (100% of eyes with microcystic changes had experienced prior optic neuritis compared with 71% of NMO eyes without microcystic abnormalities). There were no significant differences between patients with NMO with and without microcystic changes in terms of age, sex, and aquaporin 4-IgG antibody status. The mean age in this cohort was 44 years (range, 13-81 years); 84% were women; 80% were aquaporin 4-IgG seropositive; and the median Expanded Disability Status Scale score was 4.0 (interquartile range, 3.0-6.5). CONCLUSIONS AND RELEVANCE: Microcystic inner nuclear layer pathology occurs in a proportion of patients with NMO in eyes previously affected by acute optic neuritis. Additional research is needed to understand the cause of this retinal pathology and determine whether it contributes to persistent visual disability in patients with NMO following optic neuritis.