[Treatment of multiple sclerosis]. / Behandelmogelijkheden bij multiple sclerose.

Multiple sclerosis is a chronic inflammatory disease of the central nervous system, caused by an autoimmune reaction. Treatment options have largely increased over the years. In this article, we present two clinical cases. Patient A has a classic relapsing remitting course of multiple sclerosis with satisfactory effect on second line therapy. Patient B had a stable disease course until a new relapse occurred after the initiation of TNF-alpha blocking therapy because of Crohn's disease. The co-occurrence of multiple auto-immune diseases creates challenges, but also opportunities in choosing the right treatment strategy.

The role of CD56bright NK cells in neurodegenerative disorders.

Emerging evidence suggests a potential role for natural killer (NK) cells in neurodegenerative diseases, such as multiple sclerosis, Alzheimer's disease, Parkinson's disease and amyotrophic lateral sclerosis. However, the precise function of NK cells in these diseases remains ambiguous. The existence of two NK cell subsets, CD56bright and CD56dim NK cells, complicates the understanding of the contribution of NK cells in neurodegeneration as their functions within the context of neurodegenerative diseases may differ significantly. CD56bright NK cells are potent cytokine secretors and are considered more immunoregulatory and less terminally differentiated than their mostly cytotoxic CD56dim counterparts. Hence, this review focusses on NK cells, specifically on CD56bright NK cells, and their role in neurodegenerative diseases. Moreover, it explores the mechanisms underlying their ability to enter the central nervous system. By consolidating current knowledge, we aim to provide a comprehensive overview on the role of CD56bright NK cells in neurodegenerative diseases. Elucidating their impact on neurodegeneration may have implications for future therapeutic interventions, potentially ameliorating disease pathogenesis.

Outcome Reporting Bias in Clinical Trials Researching Disease-Modifying Therapy in Patients With Multiple Sclerosis.

BACKGROUND AND OBJECTIVES: Outcome reporting bias occurs when publication of trial results is dependent on clinical significance, thereby threatening the validity of trial results. Research on immunomodulatory drugs in multiple sclerosis has thrived in recent years. We aim to comprehensively examine to what extent outcome reporting bias is present in these trials and the possible underlying factors. METHODS: We identified clinical trials evaluating the efficacy and safety of immunomodulatory drugs in patients with multiple sclerosis (MS) registered in ClinicalTrials.gov after September 2007 and completed before the end of 2018. Information about study design, type of funding, and primary and secondary outcome measures was extracted from the registry. Timing of registration in relation to study initiation and subsequent amendments to the planned outcomes were reviewed. Publications related to these trials were identified in several bibliographic databases using the trial registration number. Registered primary and secondary outcomes were recorded for each trial and compared with outcomes in the publication describing the main outcomes of the trial. RESULTS: A search of ClinicalTrials.gov identified 535 eligible registered clinical trials; of these, 101 had a matching publication. Discrepancies between registered and published primary and secondary outcomes were found in 95% of the trials, including discrepancies between the registered and published primary outcomes in 26 publications. Forty-four percent of the published secondary outcomes were not included in the registry. A similar proportion of registered and nonregistered reported primary efficacy outcomes were positive (favoring the intervention). Nonindustry-funded and open-label trials in MS were more prone to selective primary outcome reporting, although these findings did not reach statistical significance. Only two-thirds of the trials were registered in ClinicalTrials.gov before the trial start date, and 62% of trials made amendments in registered outcomes during or after the trial period. DISCUSSION: Selective outcome reporting is prevalent in trials of disease-modifying drugs in people with MS. We propose methods to diminish the occurrence of this bias in future research.

The association between weight during early life and multiple sclerosis onset in a nationwide Dutch birth year cohort.

BACKGROUND: The relationship between being overweight during early life and disease course in multiple sclerosis (MS) is unresolved. We investigated the association between being overweight or obese during early life (childhood and adolescence) and MS case status, age of first symptom onset and onset type in people with MS (pwMS) of the same birth year. METHODS: We enrolled 363 PwMS and 125 healthy controls (HC) from Project Y, a Dutch population-based cross-sectional cohort study including all PwMS born in 1966 and age and sex-matched HC. The associations between weight during childhood and adolescence (non-overweight vs. overweight or obese) and MS, age at symptom onset and onset type (relapsing vs. progressive) were assessed using logistic and linear regressions. In addition, sex-separated associations were explored. RESULTS: Being overweight or obese during childhood (OR = 2.82, 95% CI 1.17-6.80) and adolescence (OR = 2.45, 95% CI 1.13-5.34) was associated with developing MS. Furthermore, being overweight or obese during adolescence was associated with a younger age of onset (ß = -0.11, p = 0.041). Of all 47 patients with a primary progressive (PP) onset type, only one patient (2.1%) was overweight or obese during childhood, whereas 45 patients with a relapsing remitting (RR) onset (14.3%) were overweight or obese during childhood (PP vs. RR p = 0.017; PP vs. HC p = 0.676; RR vs. HC, p = 0.015). However, using logistic regression analysis we did not find evidence of a significant association. CONCLUSION: In a nationwide population-based birth year cohort, being overweight or obese during childhood or adolescence is associated with MS prevalence and an earlier age of onset, but does not seem to associate with the type of onset.

The role of diet in multiple sclerosis onset and course: results from a nationwide retrospective birth-year cohort.

OBJECTIVE: To examine (1) the association between childhood diet and developing MS, age of onset and onset type and (2) the association between diet at age 50 and disability and MRI volumes in people with MS (PwMS). METHODS: The study enrolled 361 PwMS born in 1966 and 125 age- and sex-matched healthy controls (HCs). Information on individual dietary components (fruit, vegetables, red meat, oily fish, whole-grain bread and candy, snacks and fast food) and MS risk factors at the age of 10 and 50 years were collected using questionnaires. Overall diet quality score was calculated for each participant. Multivariable regression analyses were used to evaluate the association between diet at childhood and developing MS, age of onset and onset type and to evaluate diet at age 50, disability and MRI outcomes. RESULTS: Poorer overall diet quality and individual dietary components during childhood (less whole-grain bread, more candy, snacks and fast food and oily fish) were associated with developing MS and onset type (all p < 0.05), but not with the age of onset. Fruit consumption at age 50 was associated with lower disability (Q3 vs. Q1: -0.51; 95% CI: -0.89 to -0.13). Furthermore, several individual dietary components at age 50 were associated with MRI volumetric measures. Higher-diet quality at age 50 was only associated with lower lesion volumes in PwMS (Q2 vs. Q1: -0.3 mL; 95% CI: -0.5 to -0.02). INTERPRETATION: We demonstrate significant associations between dietary factors in childhood and developing MS, age of onset and onset type and between dietary factors at age 50 and disability and MRI-derived volumes.

Association of Arachidonic Acid-Derived Lipid Mediators With Disease Severity in Patients With Relapsing and Progressive Multiple Sclerosis.

BACKGROUND AND OBJECTIVES: Excessive activation of certain lipid mediator (LM) pathways plays a role in the complex pathogenesis of multiple sclerosis (MS). However, the relationship between bioactive LMs and different aspects of CNS-related pathophysiologic processes remains largely unknown. Therefore, in this study, we assessed the association of bioactive LMs belonging to the ω-3/ω-6 lipid classes with clinical and biochemical (serum neurofilament light [sNfL] and serum glial fibrillary acidic protein [sGFAP]) parameters and MRI-based brain volumes in patients with MS (PwMS) and healthy controls (HCs). METHODS: A targeted high-performance liquid chromatography-tandem mass spectrometry approach was used on plasma samples of PwMS and HCs of the Project Y cohort, a cross-sectional population-based cohort that contains PwMS all born in 1966 in the Netherlands and age-matched HCs. LMs were compared between PwMS and HCs and were correlated with levels of sNfL, sGFAP, disability (Expanded Disability Status Scale [EDSS]), and brain volumes. Finally, significant correlates were included in a backward multivariate regression model to identify which LMs best related to disability. RESULTS: The study sample consisted of 170 patients with relapsing remitting MS (RRMS), 115 patients with progressive MS (PMS), and 125 HCs. LM profiles of patients with PMS significantly differed from those of patients with RRMS and HCs, particularly patients with PMS showed elevated levels of several arachidonic acid (AA) derivatives. In particular, 15-hydroxyeicosatetraenoic acid (HETE) (r = 0.24, p < 0.001) correlated (average r = 0.2, p < 0.05) with clinical and biochemical parameters such as EDSS and sNfL. In addition, higher 15-HETE levels were related to lower total brain (r = -0.24, p = 0.04) and deep gray matter volumes (r = -0.27, p = 0.02) in patients with PMS and higher lesion volume (r = 0.15, p = 0.03) in all PwMS. DISCUSSION: In PwMS of the same birth year, we show that ω-3 and ω-6 LMs are associated with disability, biochemical parameters (sNfL, GFAP), and MRI measures. Furthermore, our findings indicate that, particularly, in patients with PMS, elevated levels of specific products of the AA pathway, such as 15-HETE, associate with neurodegenerative processes. Our findings highlight the potential relevance of ω-6 LMs in the pathogenesis of MS.

Diffusion-based structural connectivity patterns of multiple sclerosis phenotypes.

BACKGROUND: We aimed to describe the severity of the changes in brain diffusion-based connectivity as multiple sclerosis (MS) progresses and the microstructural characteristics of these networks that are associated with distinct MS phenotypes. METHODS: Clinical information and brain MRIs were collected from 221 healthy individuals and 823 people with MS at 8 MAGNIMS centres. The patients were divided into four clinical phenotypes: clinically isolated syndrome, relapsing-remitting, secondary progressive and primary progressive. Advanced tractography methods were used to obtain connectivity matrices. Then, differences in whole-brain and nodal graph-derived measures, and in the fractional anisotropy of connections between groups were analysed. Support vector machine algorithms were used to classify groups. RESULTS: Clinically isolated syndrome and relapsing-remitting patients shared similar network changes relative to controls. However, most global and local network properties differed in secondary progressive patients compared with the other groups, with lower fractional anisotropy in most connections. Primary progressive participants had fewer differences in global and local graph measures compared with clinically isolated syndrome and relapsing-remitting patients, and reductions in fractional anisotropy were only evident for a few connections. The accuracy of support vector machine to discriminate patients from healthy controls based on connection was 81%, and ranged between 64% and 74% in distinguishing among the clinical phenotypes. CONCLUSIONS: In conclusion, brain connectivity is disrupted in MS and has differential patterns according to the phenotype. Secondary progressive is associated with more widespread changes in connectivity. Additionally, classification tasks can distinguish between MS types, with subcortical connections being the most important factor.

Association of age and inflammatory disease activity in the pivotal natalizumab clinical trials in relapsing-remitting multiple sclerosis.

BACKGROUND: Focal inflammatory disease activity in relapsing-remitting multiple sclerosis (RRMS) diminishes with increasing age. Here we use patient-level data from randomised controlled trials (RCTs) of natalizumab treatment in RRMS to investigate the association of age and inflammatory disease activity. METHODS: We used patient-level data from the AFFIRM (natalizumab vs placebo in relapsing-remitting MS, NCT00027300) and SENTINEL (natalizumab plus interferon beta vs interferon beta in relapsing remitting MS, NCT00030966) RCTs. We determined the proportion of participants developing new T2 lesions, contrast-enhancing lesions (CELs) and relapses over 2 years of follow-up as a function of age, and investigated the association of age with time to first relapse using time-to-event analyses. RESULTS: At baseline, there were no differences between age groups in T2 lesion volume and number of relapses in the year before inclusion. In SENTINEL, older participants had a significantly lower number of CELs. During both trials, the number of new CELs and the proportion of participants developing new CELs were significantly lower in older age groups. The number of new T2 lesions and the proportion of participants with any radiological disease activity during follow-up were also lower in older age groups, especially in the control arms. CONCLUSIONS: Older age is associated with a lower prevalence and degree of focal inflammatory disease activity in treated and untreated RRMS. Our findings inform the design of RCTs, and suggest that patient age should be taken into consideration when deciding on immunomodulatory treatment in RRMS.

Longitudinal Changes in Cognitive Test Scores in Patients With Relapsing-Remitting Multiple Sclerosis: An Analysis of the DECIDE Dataset.

BACKGROUND AND OBJECTIVES: Cognitive impairment is a common and impactful symptom of relapsing-remitting multiple sclerosis (RRMS). Cognitive outcome measures are often used in cross-sectional studies, but their performance as longitudinal outcome measures in clinical trials is not widely researched. In this study, we used data from a large clinical trial to describe change on the Symbol Digit Modalities Test (SDMT) and the Paced Auditory Serial Addition Test (PASAT) over up to 144 weeks of follow-up. METHODS: We used the data set from DECIDE (clinicaltrials.gov identifier NCT01064401), a large randomized controlled RRMS trial to describe change on the SDMT and PASAT over 144 weeks of follow-up. We compared change on these cognitive outcomes with change on the timed 25-foot walk (T25FW), a well-established physical outcome measure. We investigated several definitions for clinically meaningful change: any change, 4-point change, 8-point change, and 20% change for the SDMT, any change, 4-point change, and 20% change for the PASAT, and 20% change for the T25FW. RESULTS: DECIDE included 1,814 trial participants. SDMT and PASAT scores steadily improved throughout follow-up: the SDMT from a mean 48.2 (SD, 16.1) points at baseline to 52.6 (SD 15.2) at 144 weeks and the PASAT from 47.0 (SD 11.3) at baseline to 50.0 (SD 10.8) at 144 weeks. This improvement in scores is most likely due to a practice effect. Throughout the trial, participants were more likely to experience improvement than worsening of their SDMT and PASAT performance, whereas the number of worsening events on the T25FW steadily increased. Changing the definition of clinically meaningful change for the SDMT and PASAT or using a 6-month confirmation changed the overall number of worsening or improvement events but did not affect the overall behavior of these measures. DISCUSSION: Our findings suggest that the SDMT and PASAT scores do not accurately reflect the steady cognitive decline that people with RRMS experience. Both outcomes show postbaseline increases in scores, which complicates the interpretation of these outcome measures in clinical trials. More research into the size of these changes is needed before recommending a general threshold for clinically meaningful longitudinal change.

Repair what is lost: Neuroprotection through neural stem cells in progressive MS.

Genchi et al.1 report the first phase 1 trial of neural stem cell transplantation in multiple sclerosis showing a reduction in gray matter atrophy. Results give hope for a new era of induced neuroprotection, especially in progressive multiple sclerosis.

Association of volumetric MRI measures and disability in MS patients of the same age: Descriptions from a birth year cohort.

BACKGROUND AND OBJECTIVES: Although MRI-based markers of neuroinflammation have proven crucial for the diagnosis of multiple sclerosis (MS), predicting clinical progression with inflammation remains difficult. Neurodegenerative markers such as brain volume loss show stronger clinical (predictive) correlations, but also harbor age-related variation that must be disentangled from disease duration. In this study we investigated how clinical disability is related to volumetric MRI measures in a cohort of MS patients and healthy controls (HC) of the same age: Project Y. METHODS: This study included 234 MS patients born in 1966 and 112 HC born between 1965 and 1967 in the Netherlands. Disability was quantified using the expanded disability status scale (EDSS), nine hole peg test (9HPT), and timed 25 foot walking test (T25FWT). Volumes were quantified on 3T MRI as normalized whole brain (NBV) and regional gray matter (GM) volumes using the same scanner and MRI protocol: cortical (normalized cortical gray matter volume; NCGMV), deep (NDGMV), thalamic (NThalV), and cerebellar (NCbV) GM volumes. In addition, mean upper cervical cord area (MUCCA), white matter lesion volume (LV), and spinal cord lesions were assessed. These measures were compared between patients and HC, and related to disability measures using linear regression. RESULTS: Mean age of people with MS (PwMS) was 52.8 years (SD 0.9) and median disease duration 15.8 years (IQR 8.7-24.8). All global and regional brain measures were lower in MS patients compared to HC. Univariate regression models showed that NDGMV (ß = -0.20) and MUCCA (ß = -0.38) were most strongly related to the EDSS in all PwMS. After subtype stratification, MUCCA was most strongly related to the EDSS (ß = -0.60) and 9HPT (ß = -0.55) in secondary progressive PwMS. Multivariate regression models demonstrated that in all PwMS, the EDSS was best explained by lower MUCCA, longer disease durations and a progressive disease course (adjusted-R (Sastre-Garriga et al., 2017) = 0.26, p < 0.001). MUCCA was a consistent correlate in separate models of the EDSS for all PwMS, relapsing and progressive onset PwMS. The 9HPT (adjusted-R (Sastre-Garriga et al., 2017) = 0.20, p < 0.001) was best explained by lower MUCCA, higher LV and pack years, while lower limb disability (adjusted-R (Sastre-Garriga et al., 2017) = 0.11, p < 0.001) was best explained by lower MUCCA, progressive onset MS and female sex. DISCUSSION: Our results indicate that in a cohort unbiased by age differences, spinal cord and deep gray matter volumes best related to physical disability. Our results support the use of these measures in clinical practice and trials.

Decrease of natalizumab drug levels after switching from intravenous to subcutaneous administration in patients with multiple sclerosis.

BACKGROUND: Natalizumab is effective in the treatment of multiple sclerosis (MS). In 2021, the European Medicines Agency approved the subcutaneous (SC) variant of natalizumab which can be used instead of intravenous administration. However, the course of drug levels varies between administration routes, and the Food and Drug Administration rejected the request for approval of natalizumab SC for reasons that were not disclosed. Our objective was to evaluate the course of natalizumab trough drug levels in patients who switched from natalizumab intravenous to SC on various treatment intervals. METHODS: The NEXT-MS trial (N=382) investigates personalised treatment of natalizumab, in which infusion intervals are prolonged based on individual natalizumab trough drug levels. In 2021, an amendment was approved allowing participants to switch from intravenous to SC administration with frequent measurements of natalizumab drug levels and antidrug antibodies (ADAs). Results were compared with linear mixed model analyses. RESULTS: Until December 2022, 15 participants switched to SC natalizumab. Natalizumab drug levels with SC administration were on average 55% lower compared with intravenous administration (Exp (estimate) 0.45, 95% CI 0.39 to 0.53, p<0.001), leading to very low trough drug levels in three patients on extended treatment intervals. No natalizumab ADAs were detected during intravenous or SC treatment. None of the participants on natalizumab SC showed evidence of MS disease activity. CONCLUSIONS: Natalizumab trough drug levels can decrease after switching from natalizumab intravenous to SC administration. We advise to monitor trough drug levels in patients with low natalizumab drug levels during intravenous treatment, patients with higher body mass index or patients on extended treatment intervals who switch to SC administration of natalizumab.

Ocrelizumab concentration and antidrug antibodies are associated with B-cell count in multiple sclerosis.

BACKGROUND: The majority of patients with multiple sclerosis on ocrelizumab have B-cell depletion after standard interval dosing of 26 weeks. With B-cell-guided dosing patients receive their next dose when B-cell repopulation occurs. Prediction of B-cell repopulation using ocrelizumab concentrations could aid in personalising treatment regimes. The objectives of this study were to evaluate the association between ocrelizumab drug concentration, antidrug antibodies (ADAs) and CD19 B-cell count, and to define a cut-off ocrelizumab concentration for start of B-cell repopulation (defined by ≥10 CD19+ B cells/µL). METHODS: In this investigator-initiated prospective study, blood samples at various time points during ocrelizumab treatment were collected from a biobank. Serum ocrelizumab concentrations and ADAs were measured with two different assays developed for this study. Data were analysed using linear mixed effect models. An receiver operating characteristic (ROC) curve was used to determine a cut-off ocrelizumab concentration for start of B-cell repopulation (defined by ≥10 cells/µL). RESULTS: A total of 452 blood samples from 72 patients were analysed. Ocrelizumab concentrations were detectable up until 53.3 weeks after last infusion and ranged between <0.0025 and 204 µg/mL after 1-67 weeks. Ocrelizumab concentration was negatively associated with B-cell count, with body mass index identified as effect modifier. We found a cut-off value of 0.06 µg/mL for start of B-cell repopulation of ≥10 cells/µL. Ocrelizumab ADAs were detectable in four patients (5.7%) with corresponding low ocrelizumab concentrations and start of B-cell repopulation. CONCLUSIONS: Serum ocrelizumab concentration was strongly associated with B-cell count. Measurement of ocrelizumab drug concentrations and ADAs could play an important role to further personalise treatment and predict the start of B-cell repopulation.

Neuroaxonal and Glial Markers in Patients of the Same Age With Multiple Sclerosis.

BACKGROUND AND OBJECTIVES: The specificity of novel blood biomarkers for multiple sclerosis (MS)-related neurodegeneration is unclear because neurodegeneration also occurs during normal aging. To understand which aspects of neurodegeneration the serum biomarkers neurofilament light (sNfL), serum glial fibrillary acidic protein (sGFAP), and serum contactin-1 (sCNTN1) reflect, we here explore their cross-sectional association with disability outcome measures and MRI volumes in a unique cohort of people with MS (PwMS) of the same age. METHODS: sNfL, sGFAP (both singe-molecule array technology) and sCNTN1 (Luminex) were measured in serum samples of 288 PwMS and 125 healthy controls (HCs) of the Project Y cohort, a population-based cross-sectional study of PwMS born in the Netherlands in 1966 and age-matched HC. RESULTS: sNfL (9.83 pg/mL [interquartile range {IQR}: 7.8-12.0]) and sGFAP (63.7 pg/mL [IQR: 48.5-84.5]) were higher in PwMS compared with HC (sNfL: 8.8 pg/mL [IQR: 7.0-10.5]; sGFAP: 51.7 pg/mL [IQR: 40.1-68.3]) (p < 0.001), whereas contactin-1 (7,461.3 pg/mL [IQR: 5,951.8-9,488.6]) did not significantly differ between PwMS compared with HC (7,891.2 pg/mL [IQR: 6,120.0-10,265.8]) (p = 0.068). sNfL and sGFAP levels were 1.2-fold higher in secondary progressive patients (SPMS) compared with relapsing remitting patients (p = 0.009 and p = 0.043). Stratified by MS subtype, no relations were seen for CNTN1, whereas sNfL and sGFAP correlated with the Expanded Disability Status Scale (ρ = 0.43 and ρ = 0.39), Nine-Hole Peg Test, Timed 25-Foot Walk Test, and Symbol Digit Modalities Test (average ρ = 0.38) only in patients with SPMS. Parallel to these clinical findings, correlations were only found for sNfL and sGFAP with MRI volumes. The strongest correlations were observed between sNfL and thalamic volume (ρ = -0.52) and between sGFAP with deep gray matter volume (ρ = - 0.56) in primary progressive patients. DISCUSSION: In our cohort of patients of the same age, we report consistent correlations of sNfL and sGFAP with a range of metrics, especially in progressive MS, whereas contactin-1 was not related to clinical or MRI measures. This demonstrates the potential of sNfL and sGFAP as complementary biomarkers of neurodegeneration, reflected by disability, in progressive MS.

Adipokines in multiple sclerosis patients are related to clinical and radiological measures.

BACKGROUND: An imbalance of adipokines, hormones secreted by white adipose tissue, is suggested to play a role in the immunopathology of multiple sclerosis (MS). In people with MS (PwMS) of the same age, we aimed to determine whether the adipokines adiponectin, leptin, and resistin are associated with MS disease severity. Furthermore, we aimed to investigate whether these adipokines mediate the association between body mass index (BMI) and MS disease severity. METHODS: Adiponectin, resistin, and leptin were determined in serum using ELISA. 288 PwMS and 125 healthy controls (HC) were included from the Project Y cohort, a population-based cross-sectional study of people with MS born in the Netherlands in 1966, and age and sex-matched HC. Adipokine levels and BMI were related to demographic, clinical and disability measures, and MRI-based brain volumes. RESULTS: Adiponectin levels were 1.2 fold higher in PwMS vs. HC, especially in secondary progressive MS. Furthermore, we found a sex-specific increase in adiponectin levels in primary progressive (PP) male patients compared to male controls. Leptin and resistin levels did not differ between PwMS and HC, however, leptin levels were associated with higher disability (EDSS) and resistin strongly related to brain volumes in progressive patients, especially in several grey matter regions in PPMS. Importantly, correction for BMI did not significantly change the results. CONCLUSION: In PwMS of the same age, we found associations between adipokines (adiponectin, leptin, and resistin) and a range of clinical and radiological metrics. These associations were independent of BMI, indicating distinct mechanisms.

Ocrelizumab Concentration Is a Good Predictor of SARS-CoV-2 Vaccination Response in Patients with Multiple Sclerosis.

Ocrelizumab, an anti-CD20 monoclonal antibody, counteracts induction of humoral immune responses after severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) vaccinations in patients with multiple sclerosis (MS). We aimed to assess if serum ocrelizumab concentration measured at the time of vaccination could predict the humoral response after SARS-CoV-2 vaccination. In 52 patients with MS, we found ocrelizumab concentration at the time of vaccination to be a good predictor for SARS-CoV-2 IgG anti-RBD titers after vaccination (comparable to B-cell count). As the course of ocrelizumab concentration may be predicted using pharmacokinetic models, this may be a superior biomarker to guide optimal timing for vaccinations in B-cell depleted patients with MS. ANN NEUROL 2023;93:103-108.

Spinal cord lesions and brain grey matter atrophy independently predict clinical worsening in definite multiple sclerosis: a 5-year, multicentre study.

OBJECTIVES: To evaluate the combined contribution of brain and cervical cord damage in predicting 5-year clinical worsening in a multicentre cohort of definite multiple sclerosis (MS) patients. METHODS: Baseline 3.0T brain and cervical cord T2-weighted and three-dimensional T1-weighted MRI was acquired in 367 patients with MS (326 relapse-onset and 41 progressive-onset) and 179 healthy controls. Expanded Disability Status Scale (EDSS) score was obtained at baseline and after a median follow-up of 5.1 years (IQR=4.8-5.2). At follow-up, patients were classified as clinically stable/worsened according to EDSS changes. Generalised linear mixed models identified predictors of clinical worsening, evolution to secondary progressive (SP) MS and reaching EDSS=3.0, 4.0 and 6.0 milestones at 5 years. RESULTS: At follow-up, 120/367 (33%) patients with MS worsened clinically; 36/256 (14%) patients with relapsing-remitting evolved to SPMS. Baseline predictors of EDSS worsening were progressive-onset versus relapse-onset MS (standardised beta (ß)=0.97), higher EDSS (ß=0.41), higher cord lesion number (ß=0.41), lower normalised cortical volume (ß=-0.15) and lower cord area (ß=-0.28) (C-index=0.81). Older age (ß=0.86), higher EDSS (ß=1.40) and cord lesion number (ß=0.87) independently predicted SPMS conversion (C-index=0.91). Predictors of reaching EDSS=3.0 after 5 years were higher baseline EDSS (ß=1.49), cord lesion number (ß=1.02) and lower normalised cortical volume (ß=-0.56) (C-index=0.88). Baseline age (ß=0.30), higher EDSS (ß=2.03), higher cord lesion number (ß=0.66) and lower cord area (ß=-0.41) predicted EDSS=4.0 (C-index=0.92). Finally, higher baseline EDSS (ß=1.87) and cord lesion number (ß=0.54) predicted EDSS=6.0 (C-index=0.91). CONCLUSIONS: Spinal cord damage and, to a lesser extent, cortical volume loss helped predicting worse 5-year clinical outcomes in MS.