Serious safety events in rituximab-treated multiple sclerosis and related disorders

Long-term analysis of infections and associated risk factors in patients with multiple sclerosis treated with ocrelizumab: pooled analysis of 13 interventional clinical trials

Background

Patients with multiple sclerosis (PwMS) have an increased risk of infections.

Objectives

To characterize incidence, clinical characteristics, outcomes and risk factors of infections, and serious infections (SIs) in ocrelizumab (OCR)-treated PwMS.

Design

Post-hoc analysis of pooled data from 6155 patients in 13 clinical trials.

Methods

Descriptive analyses of clinical characteristics and outcomes were reported over ⩽14 years. A Poisson Generalized Estimating Equation model was constructed to examine risk factors in a subgroup of patients with longer exposure to OCR (n = 2092).

Results

Over a median (max) treatment period of 3.7 (13.9) years, 420/6155 patients (6.8%) experienced 583 SIs, excluding coronavirus disease 2019. Incidence rates in relapsing multiple sclerosis (RMS; 1.50 per 100 patient years [95% confidence interval (CI): 1.34-1.68]) and progressive multiple sclerosis (PMS; 3.70 [95% CI: 3.27-4.17]) remained stable over this period. Lower respiratory tract, urinary tract, abdominal and gastrointestinal, and skin infections were the most commonly reported SIs. Most SIs (~90%) resolved, and treatment with OCR was continued in >80% of cases. The presence of 1 or ⩾2 comorbidities (rate ratio = 1.66, 2.73, respectively), recent relapse activity (2.06), and Expanded Disability Status Scale (EDSS) score ⩾6.0 (2.02) were significant risk factors for SIs in patients with RMS treated over a median (max) period of 8.3 (11.2) years. In patients with primary PMS treated over a median (max) period of 7.1 (11.8) years, an EDSS score ⩾6.0 was associated with the greatest risk of SIs, a 4-fold increase (rate ratio, 4.31), followed by abnormal immunoglobulin (Ig)M levels (1.89), the presence of ⩾2 comorbidities (1.80), and having overweight/obesity (1.46). Time on OCR and abnormal IgG levels were not significantly associated with an increased SI risk.

Conclusion

Continuous long-term treatment with OCR is associated with a manageable infection risk profile. Optimal disease control and addressing modifiable risk factors may reduce the risk of infections.

B-cell Depletion Therapy in Pediatric Neuroinflammatory Disease

PURPOSE OF REVIEW

B-cell depletion therapy, including anti-CD20 and anti-CD19 therapies, is increasingly used for a variety of autoimmune and conditions, including those affecting the central nervous system. However, B-cell depletion therapy use can be complicated by adverse effects associated with administration and immunosuppression. This review aims to summarize the application of anti-CD20 and anti-CD19 therapies for the pediatric neurologist and neuroimmunologist.

RECENT FINDINGS

Most existing literature come from clinical trials with adult patients, although more recent studies are now capturing the effects of these therapies in children. The most common side effects include infusion related reactions and increased infection risk from immunosuppression. Several strategies can mitigate infusion related reactions. Increased infections due to persistent hypogammaglobulinemia can benefit from replacement immunoglobulin. B-cell depletion therapies can be safe and effective in pediatric patients. Anticipation and mitigation of common adverse effects through primary prevention strategies, close monitoring, and appropriate symptomatic management can improve safety and tolerability.

MS treatment de-escalation: review and commentary

Almost all currently licensed disease-modifying therapies (DMTs) for MS treatment require prolonged if not lifelong administration. Yet, as people age, the immune system has increasingly reduced responsiveness, known as immunosenescence. Many MS DMTs reduce the responsiveness of the immune system, increasing the risks for infections and possibly cancers. As people with MS (pwMS) age, it is recognized that inflammatory MS activity declines. Several studies have addressed de-escalation of DMTs for relapsing MS under special circumstances. Here, we review evidence for de-escalating DMTs as a strategy that is particularly relevant to pwMS of older age. Treatment de-escalation can involve various strategies, such as extended or reduced dosing, switching from high-efficacy DMTs having higher risks to moderately effective DMTs with lesser risks, or treatment discontinuation. Studies have suggested that for natalizumab extended dosing maintained clinical efficacy while reducing the risk of PML. Extended interval dosing of ocrelizumab mitigated the decline of Ig levels. Retrospective and observational discontinuation studies demonstrate that age is an essential modifier of drug efficacy. Discontinuation of MS treatment in older patients has been associated with a stable disease course, while younger patients who discontinued treatment were more likely to experience new clinical activity. A recently completed 2-year randomized-controlled discontinuation study in 260 stable pwMS > 55 years found stable clinical multiple sclerosis with only a small increased risk of new MRI activity upon discontinuation. DMT de-escalation or discontinuation in MS patients older than 55 years may be non-inferior to continued treatment with immunosuppressive agents having higher health risks. However, despite several small studies, a definite conclusion about treatment de-escalation in older pwMS will require larger and longer studies. Ideally, comparison of de-escalation versus continuation versus discontinuation of DMTs should be done by prospective randomized-controlled trials enrolling sufficient numbers of subjects to allow comparisons for MS patients of both sexes within age groups, such as 55-59, 60-65, 66-69, etc. Optimally, such studies should be 3 years or longer and should incorporate testing for specific markers of immunosenescence (such as T-cell receptor excision circles) to account for differential aging of individuals.

De-escalation and Discontinuation of Disease-Modifying Therapies in Multiple Sclerosis

PURPOSE OF REVIEW

Long-term use of multiple sclerosis (MS) disease-modifying therapies (DMTs) is standard practice to prevent accumulation of disability. Immunosenescence and other age-related changes lead to an altered risk-benefit ratio for older patients on DMTs. This article reviews recent research on the topic of de-escalation and discontinuation of MS DMTs.

RECENT FINDINGS

Observational and interventional studies have shed light on what happens to patients who de-escalate or discontinue DMTs and the factors, such as age, treatment type, and presence of recent disease activity, that influence outcomes. Though many questions remain, recent findings have been valuable for the development of an evidence-based approach to making de-escalation and discontinuation decisions in MS.

Clinical and Immunological Impact of Ocrelizumab Extended Interval Dosing in Multiple Sclerosis: A Single-Center, Real-World Experience

Ocrelizumab (OCR), an anti-CD20 monoclonal antibody, is approved for treating relapsing remitting (RR) and primary progressive (PP) multiple sclerosis (MS). The standard interval dosing (SID) regimen requires intravenous infusions every six months. Experience of extended dosing due to COVID-19 pandemic-related issues suggests that this strategy may provide comparable efficacy while reducing treatment burden and healthcare costs. This study aimed to evaluate clinical effectiveness, changes in B- and T-cell count, and immunoglobulin dynamics associated with extended interval dosing (EID) of ocrelizumab in a real-world setting. We retrospectively included RRMS or PPMS patients treated with OCR that had already received two OCR cycles and with at least 6 months of follow up after the last infusion. EID was defined as a ≥4 weeks delay compared to SID. Clinical outcomes were occurrence of relapses, MRI activity, 6-months confirmed disability progression (CDP) and their combination (No Evidence of Disease Activity, NEDA-3). We also evaluated changes in CD19+ B cell count, CD4+ and CD8+ T cell count, immunoglobulin titers, and occurrence of hypogammaglobulinemia (hypo-Ig). Frequency tests, multivariate regression models, and survival analysis were applied as appropriate. We analyzed data on 93 subjects (75.3% RRMS) for a total of 389 infusions (272 SID, 117 EID). Clinical and MRI activity, CDP, and NEDA 3 did not significantly differ between EID and SID. EID was associated with lower rates of B-cell depletion. T-cell dynamics and incidence of hypo-Ig were comparable following EID and SID. Hypo-IgG at index infusion was associated with further occurrence of hypo-IgG; male sex and hypo-IgM at index infusion were independently associated with hypo-IgM. In conclusion, OCR EID does not impact MS clinical and radiological outcomes, although it interferes with B-cell dynamics. These findings provide support for a tailored schedule of OCR in MS.

Multiple Sclerosis, Rituximab, Hypogammaglobulinemia, and Risk of Infections

BACKGROUND AND OBJECTIVES

B-cell-depleting therapies increase the risk of infections and hypogammaglobulinemia. These relationships are poorly understood. The objectives of these analyses were to estimate how much of this rituximab-associated infection risk is mediated by hypogammaglobulinemia and to identify other modifiable risk factors in persons with multiple sclerosis (pwMS).

METHODS

We conducted a retrospective cohort study of rituximab-treated pwMS from January 1, 2008, to December 31, 2020, in Kaiser Permanente Southern California. Cumulative rituximab dose was defined as ≤2, >2 and ≤4, or >4 g. Serious infections were defined as infections requiring or prolonging hospitalizations, and recurrent outpatient infections as seeking care for ≥3 within 12 months. Exposures, outcomes, and covariates were collected from the electronic health record. Adjusted hazard ratios (aHRs) were estimated using Andersen-Gill hazards models, and generalized estimating equations were used to examine correlates of IgG values. Cross-sectional causal mediation analyses of rituximab and hypogammaglobulinemia were conducted.

RESULTS

We identified 2,482 pwMS who were treated with rituximab for a median of 2.4 years (interquartile range = 1.3-3.9). The average age at rituximab initiation was 43.0 years, 71.9% were female, 49.7% were White, non-Hispanic patients, and 29.6% had advanced disability (requiring walker or worse). Seven hundred patients (28.2%) developed recurrent outpatient infections, 155 (6.2%) developed serious infections, and only 248 (10.0%) had immunoglobulin G (IgG) < 700 mg/dL. Higher cumulative rituximab dose (>4 g) was correlated with lower IgG levels (Beta = -58.8, p < 0.0001, ref ≤2 g) and, in models mutually adjusted for hypogammaglobulinemia, both were independently associated with an increased risk of serious (>4 g, aHR = 1.56, 95% CI 1.09-2.24; IgG < 500, aHR = 2.98, 95% CI 1.56-5.72) and outpatient infections (>4 g, aHR = 1.73, 95% CI 1.44-2.06; IgG < 500 aHR = 2.06, 95% CI 1.52-2.80; ref = IgG ≥ 700). Hypogammaglobulinemia explained at most 17.9% (95% CI -47.2-119%) of serious infection risk associated with higher cumulative rituximab exposure but was not significant for outpatient infections. Other independent modifiable risk factors were advanced physical disability for serious (aHR = 5.51, 95% CI 3.71-8.18) and outpatient infections (aHR = 1.24, 95% CI 1.06-1.44) and COPD (aHR = 1.68, 95% CI 1.34-2.11) and obesity (aHR = 1.25, 95% CI 1.09-1.45) for outpatient infections.

DISCUSSION

Higher cumulative rituximab doses increase the risk of infections even in this population where 90% of patients maintained normal IgG levels. Clinicians should strive to use minimally effective doses of rituximab and other B-cell-depleting therapies and consider important comorbidities to minimize risks of infections.

Hypogammaglobulinemia and infections in patients with multiple sclerosis treated with anti-CD20 treatments: a systematic review and meta-analysis of 19,139 multiple sclerosis patients

Background

Recent years have seen the emergence of disease-modifying therapies in multiple sclerosis (MS), such as anti-cluster of differentiation 20 (anti-CD20) monoclonal antibodies, aiming to modulate the immune response and effectively manage MS. However, the relationship between anti-CD20 treatments and immunoglobulin G (IgG) levels, particularly the development of hypogammaglobulinemia and subsequent infection risks, remains a subject of scientific interest and variability. We aimed to investigate the intricate connection between anti-CD20 MS treatments, changes in IgG levels, and the associated risk of hypogammaglobulinemia and subsequent infections.

Method

PubMed, Scopus, Embase, Cochrane, and Web of Science databases have been searched for relevant studies. The "R" software utilized to analyze the occurrence of hypogammaglobulinemia, infections and mean differences in IgG levels pre- and post-treatment. The subgrouping analyses were done based on drug type and treatment duration. The assessment of heterogeneity utilized the I2 and chi-squared tests, applying the random effect model.

Results

Thirty-nine articles fulfilled our inclusion criteria and were included in our review which included a total of 20,501 MS patients. The overall prevalence rate of hypogammaglobulinemia was found to be 11% (95% CI: 0.08 to 0.15). Subgroup analysis based on drug type revealed varying prevalence rates, with rituximab showing the highest at 18%. Subgroup analysis based on drug usage duration revealed that the highest proportion of hypogammaglobulinemia occurred in individuals taking the drugs for 1 year or less (19%). The prevalence of infections in MS patients with a focus on different infection types stratified by the MS drug used revealed that pulmonary infections were the most prevalent (9%) followed by urinary tract infections (6%), gastrointestinal infections (2%), and skin and mucous membrane infections (2%). Additionally, a significant decrease in mean IgG levels after treatment compared to before treatment, with a mean difference of 0.57 (95% CI: 0.22 to 0.93).

Conclusion

This study provides a comprehensive analysis of the impact of anti-CD20 drugs on serum IgG levels in MS patients, exploring the prevalence of hypogammaglobulinemia, based on different drug types, treatment durations, and infection patterns. The identified rates and patterns offer a foundation for clinicians to consider in their risk-benefit.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=518239, CRD42024518239.

Anti-CD20 monoclonal antibodies in multiple sclerosis: Rethinking the current treatment strategy

Anti-CD20 monoclonal antibodies are highly-effective B-cell-depleting therapies in multiple sclerosis (MS). These treatments have expanded the arsenal of highly effective disease-modifying therapies, and have changed the landscape in understanding the pathophysiology of MS and the natural course of the disease. Nevertheless, these treatments come at the cost of immunosuppression and risk of serious infections, diminished vaccination response and treatment-related secondary hypogammaglobulinemia. However, the COVID pandemic has given way to a possibility of readapting these therapies, with most notably extended dosing intervals. While these new strategies show efficacy in maintaining inflammatory MS disease control, and although it is tempting to speculate that tailoring CD20 therapies will reduce the negative outcomes of long-term immunosuppression, it is unknown whether they provide meaningful benefit in reducing the risk of treatment-related secondary hypogammaglobulinemia and serious infections. This review highlights the available anti-CD20 therapies that are available for treating MS patients, and sheds light on encouraging data, which propose that tailoring anti-CD20 monoclonal antibodies is the next step in rethinking the current treatment strategy.

Control of disease activity with large extended-interval dosing of rituximab/ocrelizumab in highly active pediatric multiple sclerosis

Recent studies in adults suggested that extended-interval dosing of rituximab/ocrelizumab (RTX/OCR) larger than 12 months was safe and could improve safety. This was an observational cohort study of very active pediatric-onset multiple sclerosis (PoMS) (median (range) age, 16 (12-17) years) treated with RTX/OCR with 6 month standard-interval dosing (n = 9) or early extended-interval dosing (n = 12, median (range) interval 18 months (12-25)). Within a median (range) follow-up of 31 (12-63) months after RTX/OCR onset, one patient (standard-interval) experienced relapse and no patient showed disability worsening or new T2-weighted lesions. This study suggests that the effectiveness of RTX/OCR is maintained with a median extended-interval dosing of 18 months in patients with very active PoMS.

Advances in Multiple Sclerosis Neurotherapeutics, Neuroprotection, and Risk Mitigation Strategies

The treatment of patients with relapsing multiple sclerosis (MS) has advanced tremendously over the past few decades. More efficacious therapies have been approved, which can significantly reduce the inflammatory process of relapsing MS. Neuroprotection by controlling this pathophysiology is important given our current limitations to control progressive MS and induce neurorepair. Here, the authors discuss the current landscape of neurotherapeutics for relapsing MS focusing on newer disease-modifying treatments and their use. Risk mitigation of these medications can greatly improve their safety and improve their benefit-risk balance. The authors discuss treatment strategies for risk mitigation including treatment discontinuation and de-escalation.

A Proposed Approach to Screening and Surveillance Labs for Patients With Multiple Sclerosis on Anti-CD20 Therapy

Background

Anti-CD20 therapies have proven to be highly effective and safe therapies for multiple sclerosis (MS) and have had rapid uptake in the MS community. However, no clear consensus has arisen regarding an approach to screening or surveillance lab monitoring.

Recent Findings

Based on current evidence, for screening labs before anti-CD20 initiation, we propose checking liver function test (LFT), complete blood count with differential (CBC), absolute B-cell count, quantitative immunoglobulins, hepatitis B virus serologies, varicella zoster virus IgG, John Cunningham virus (JCV) status, and age-appropriate vaccination history. For surveillance monitoring in an otherwise asymptomatic individual, we propose biannual LFTs and CBC, quantitative immunoglobulins annually after year 3, absolute B-cell count at month 6 and in the setting of relapse, and JCV only if clinical or radiographic features of progressive multifocal leukoencephalopathy arise. For ublituximab, pregnancy testing is additionally recommended before each infusion.

Implications for Practice

We propose evidence-based screening and safety surveillance labs which take into account likelihood of changing management in an otherwise stable or asymptomatic individual.

Update on the diagnosis and treatment of neuromyelitis optica spectrum disorders (NMOSD) - revised recommendations of the Neuromyelitis Optica Study Group (NEMOS). Part II: Attack therapy and long-term management

This manuscript presents practical recommendations for managing acute attacks and implementing preventive immunotherapies for neuromyelitis optica spectrum disorders (NMOSD), a rare autoimmune disease that causes severe inflammation in the central nervous system (CNS), primarily affecting the optic nerves, spinal cord, and brainstem. The pillars of NMOSD therapy are attack treatment and attack prevention to minimize the accrual of neurological disability. Aquaporin-4 immunoglobulin G antibodies (AQP4-IgG) are a diagnostic marker of the disease and play a significant role in its pathogenicity. Recent advances in understanding NMOSD have led to the development of new therapies and the completion of randomized controlled trials. Four preventive immunotherapies have now been approved for AQP4-IgG-positive NMOSD in many regions of the world: eculizumab, ravulizumab - most recently-, inebilizumab, and satralizumab. These new drugs may potentially substitute rituximab and classical immunosuppressive therapies, which were as yet the mainstay of treatment for both, AQP4-IgG-positive and -negative NMOSD. Here, the Neuromyelitis Optica Study Group (NEMOS) provides an overview of the current state of knowledge on NMOSD treatments and offers statements and practical recommendations on the therapy management and use of all available immunotherapies for this disease. Unmet needs and AQP4-IgG-negative NMOSD are also discussed. The recommendations were developed using a Delphi-based consensus method among the core author group and at expert discussions at NEMOS meetings.

Corticosteroid-induced low immunoglobulin levels in multiple sclerosis - A confounding factor

BACKGROUND

Changes in immunoglobulin (Ig) levels may occur in association with various drugs targeting immunity, including those used to treat multiple sclerosis (MS). However, influence of high-dose corticosteroids (CS) is poorly described.

OBJECTIVE

To describe influence of disease-modifying drugs (DMD) and CS on the Ig levels.

METHODS

Monocentric retrospective study examining changes in Ig levels in relation with CS intake in a series of 304 consecutive MS patients (and 1204 samples) followed or hospitalized for 7 years in a single centre. Ig levels are routinely collected in MS patients followed in our centre.

RESULTS

IgG levels were significantly lower in MS patients exposed to CS infusion during the last 24 months. IgG levels were also lower in DMD-treated patients exposed to CS. DMD-specific decrease of IgM levels was confirmed in interaction with CS.

CONCLUSION

Stratification by CS exposure suggested that a decrease in Ig levels occurring during DMD treatment was strongly associated with CS infusion. The strong and persistent effect of CS on Ig levels could be a hidden variable and should be considered in further studies targeting Ig levels.

Ocrelizumab B-cell repopulation-guided extended interval dosing versus standard dosing - similar clinical efficacy with decreased immunoglobulin M deficiency rates

BACKGROUND

Ocrelizumab (OCR) is a humanized anti-CD20 monoclonal antibody used in treatment of multiple sclerosis. The standard dosing (SD) regimen consists of OCR maintenance infusions every 6 months. In B-cell repopulation-guided extended interval dosing (EID), repeat infusions are delayed until there is evidence for B-cell repopulation.

OBJECTIVES

To compare frequencies of 'no evidence of disease activity' (NEDA-3) and immunoglobulin G (hypo-IgG; <600 mg/dL) and M (hypo-IgM; <40 mg/dL) deficiencies in persons with multiple sclerosis (PwMS) treated with OCR B-cell repopulation-guided EID versus SD.

METHODS

Two-center retrospective study comparing frequencies of NEDA-3 and hypo-IgG and hypo-IgM in PwMS treated with OCR B-cell repopulation-guided EID versus SD using a multivariate generalized linear model adjusted for age, sex, and treatment duration.

RESULTS

A total of 112 OCR-treated PwMS were included (B-cell repopulation-guided EID n = 52; SD n = 60) with average infusion intervals of 319 (246-485) days (EID) and 184 (170-218) days (SD). There was no significant difference in NEDA-3 (EID: 47/52 [90.4 %]; SD: 50/60 [83.3 %]; p = 0.161) or hypo-IgG (EID: 1/52 [1.9 %]; SD: 4/60 [6.7 %]; p = 0.298) rates. Hypo-IgM was significantly less common in EID (EID: 9/52 [17.3 %] vs. SD: 34/60 [55 %]; p<0.001) upon assessment 1099 (475-1436) days (EID) and 980 (409-1846) days (SD) post-initiation of OCR. Hypo-IgM was associated with average infusion interval length (p = 0.005) and total number of OCR cycles (p = 0.003).

CONCLUSIONS

OCR B-cell repopulation-guided EID may be a safe alternative to traditional SD with similar efficacy and significantly less hypo-IgM rates.

Secondary hypogammaglobulinemia in patients with multiple sclerosis on anti-CD20 therapy: Pathogenesis, risk of infection, and disease management

Hypogammaglobulinemia is characterized by reduced serum immunoglobulin levels. Secondary hypogammaglobulinemia is of considerable interest to the practicing physician because it is a potential complication of some medications and may predispose patients to serious infections. Patients with multiple sclerosis (MS) treated with B-cell-depleting anti-CD20 therapies are particularly at risk of developing hypogammaglobulinemia. Among these patients, hypogammaglobulinemia has been associated with an increased risk of infections. The mechanism by which hypogammaglobulinemia arises with anti-CD20 therapies (ocrelizumab, ofatumumab, ublituximab, rituximab) remains unclear and does not appear to be simply due to the reduction in circulating B-cell levels. Further, despite the association between anti-CD20 therapies, hypogammaglobulinemia, and infections, there is currently no generally accepted monitoring and treatment approach among clinicians treating patients with MS. Here, we review the literature and discuss possible mechanisms of secondary hypogammaglobulinemia in patients with MS, hypogammaglobulinemia results in MS anti-CD20 therapy clinical trials, the risk of infection for patients with hypogammaglobulinemia, and possible strategies for disease management. We also include a suggested best-practice approach to specifically address secondary hypogammaglobulinemia in patients with MS treated with anti-CD20 therapies.

Multiple Sclerosis, Disease-Modifying Therapies, and Infections

BACKGROUND AND OBJECTIVES

The use of highly effective multiple sclerosis (MS) disease-modifying therapies (DMTs) is rapidly increasing. Yet, little is known about their real-world risks of infections. The goals of this study were to assess the comparative risk of outpatient and serious infections across DMTs in a large, diverse, U.S. cohort and determine whether such risks are attributable to DMTs, having MS, or other factors.

METHODS

We conducted a retrospective cohort study of Kaiser Permanente Southern California members from 2008 through 2020 with MS and non-MS controls matched on age, sex, race, and ethnicity. MS treatments, serious (those requiring hospitalization) and outpatient infections, and covariates were collected from the electronic health record. Adjusted hazard ratios (aHR) and risk ratios (aRR) were estimated using the Cox and Poisson regression, respectively.

RESULTS

Six thousand, six hundred and twenty-six patients with MS with 11,929 treatment episodes (2,487 rituximab, 546 natalizumab, 298 fingolimod, 4,629 interferon-beta/glatiramer acetate, IFN/GLAT, and 3,969 untreated) and 33,550 population controls were included in the analyses. The average age at treatment start ranged from 38.9 to 49.2 years, and 74% were women. Untreated (aRR = 1.39, [95% CI = 1.35-1.44]) and IFN/GLAT-treated patients with MS (aRR = 1.60, [95% CI = 1.56-1.65]) had a higher risk of outpatient infections and serious infections (aHR = 2.97, [95% CI = 2.65-3.32 and aHR = 2.31, [95% CI = 2.04-2.62], respectively) compared with controls. Rituximab (aRR = 1.19, [95% CI = 1.14-1.25]), fingolimod (aRR = 1.22, [95% CI = 1.09-1.37]), and to a lesser extent, natalizumab treatment (aRR = 1.08, [95% CI = 0.97-1.20]) were associated with an increased risk of outpatient infections compared with IFN/GLAT. Rituximab (aHR = 1.41, [95% CI = 1.09-1.84]) and natalizumab (aHR = 1.40, [95% CI = 0.96-2.04]) treatment were associated with a similar increased risk of serious infections compared with IFN/GLAT. The only treatment-specific association identified was fingolimod with outpatient herpetic infections. Higher comorbidity index, previous hospitalization for infections, and advanced disability significantly increased the risk of serious infections independent of DMTs. Hospitalization for UTI-related pseudorelapses accounted for 24%-48% of serious infections.

DISCUSSION

Patients with MS have higher risks of outpatient and serious infections compared with patients without MS. The risk of outpatient infections was similarly increased by rituximab and fingolimod and serious infections by rituximab and natalizumab compared with IFN/GLAT. Steps to minimize risks include optimizing bladder care, comorbidity prevention, varicella vaccination, and considering discontinuing or avoiding DMT use in patients with advanced disability and/or previous hospitalizations for infections.

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.

Assessing Sustained B-Cell Depletion and Disease Activity in a French Multiple Sclerosis Cohort Treated by Long-Term IV Anti-CD20 Antibody Therapy

Few studies have investigated sustained B-cell depletion after long-term intravenous (IV) anti-CD20 B-cell depleting therapy (BCDT) in multiple sclerosis (MS) with respect to strict and/or minimal disease activity. The main objective of this study was to investigate how sustained B-cell depletion after BCDT influences clinical and radiological stability as defined by "no evidence of disease activity" (NEDA-3) and "minimal evidence of disease activity" (MEDA) status in MS patients at 12 and 18 months. Furthermore, we assessed the frequency of serious adverse events (SAE), and the influence of prior lymphocytopenia-inducing treatment (LIT) on lymphocyte subset counts and gammaglobulins in MS patients receiving long-term BCDT. We performed a retrospective, prospectively collected, study in a cohort of 192 MS patients of all clinical phenotypes treated by BCDT between January 2014 and September 2021. Overall, 84.2% and 96.9% of patients attained NEDA-3 and MEDA status at 18 months, respectively. Sustained CD19+ depletion was observed in 85.8% of patients at 18 months. No significant difference was observed when comparing patients achieving either NEDA-3 or MEDA at 18 months and sustained B-cell depletion. Compared to baseline levels, IgM and IgG levels on BCDT significantly decreased at 6 months and 30 months, respectively. Patients receiving LIT prior to BCDT showed significant CD4+ lymphocytopenia and lower IgG levels compared to non-LIT patients. Grade 3 or above SAEs were rare. As nearly all patients achieved MEDA at 18 months, we suggest tailoring IV BCDT after 18 months given the occurrence of lymphocytopenia, hypogammaglobulinemia, and SAE after this time point.

Continued dysregulation of the B cell lineage promotes multiple sclerosis activity despite disease modifying therapies

A clear understanding of the origin and role of the different subtypes of the B cell lineage involved in the activity or remission of multiple sclerosis (MS) is important for the treatment and follow-up of patients living with this disease. B cells, however, are dynamic and can play an anti-inflammatory or pro-inflammatory role, depending on their milieu. Depletion of B cells has been effective in controlling the progression of MS, but it can have adverse side effects. A better understanding of the role of the B cell subtypes, through the use of surface biomarkers of cellular activity with special attention to the function of memory and other regulatory B cells (Bregs), will be necessary in order to offer specific treatments without inducing undesirable effects.

Rituximab De-escalation in Patients With Neuromyelitis Optica Spectrum Disorder

BACKGROUND AND OBJECTIVES

Exit strategies such as de-escalations have not been evaluated for rituximab in patients with neuromyelitis optica spectrum disorder (NMOSD). We hypothesized that they are associated with disease reactivations and aimed to estimate this risk.

METHODS

We describe a case series of real-world de-escalations from the French NMOSD registry (NOMADMUS). All patients met the 2015 International Panel for NMO Diagnosis (IPND) diagnostic criteria for NMOSD. A computerized screening of the registry extracted patients with rituximab de-escalations and at least 12 months of subsequent follow-up. We searched for 7 de-escalation regimens: scheduled discontinuations or switches to an oral treatment after single infusion cycles, scheduled discontinuations or switches to an oral treatment after periodic infusions, de-escalations before pregnancies, de-escalations after tolerance issues, and increased infusion intervals. Rituximab discontinuations motivated by inefficacy or for unknown purposes were excluded. The primary outcome was the absolute risk of NMOSD reactivation (one or more relapses) at 12 months. AQP4+ and AQP4- serotypes were analyzed separately.

RESULTS

We identified 137 rituximab de-escalations between 2006 and 2019 that corresponded to a predefined group: 13 discontinuations after a single infusion cycle, 6 switches to an oral treatment after a single infusion cycle, 9 discontinuations after periodic infusions, 5 switches to an oral treatment after periodic infusions, 4 de-escalations before pregnancies, 9 de-escalations after tolerance issues, and 91 increased infusion intervals. No group remained relapse-free over the whole de-escalation follow-up (mean: 3.2 years; range: 0.79-9.5), except pregnancies in AQP+ patients. In all groups combined and within 12 months, reactivations occurred after 11/119 de-escalations in patients with AQP4+ NMOSD (9.2%, 95% CI [4.7-15.9]), from 0.69 to 10.0 months, and in 5/18 de-escalations in patients with AQP4- NMOSD (27.8%, 95% CI [9.7-53.5]), from 1.1 to 9.9 months.

DISCUSSION

There is a risk of NMOSD reactivation whatever the rituximab de-escalation regimen.

TRIAL REGISTRATION INFORMATION

Registered on ClinicalTrials.gov: NCT02850705.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that de-escalation of rituximab increases the probability of disease reactivation.

Moving toward personalized B cell depletion in multiple sclerosis?

B cell depletion is becoming a preferred long-term treatment even in early multiple sclerosis, but concerns about the risks of impaired immune competence persist. In their observational study Schuckmann et al. thoroughly assessed the impact of B cell-adapted extended interval dosing on immunoglobulin levels as a surrogate of adverse immunosuppressive effects.

Infectious risk when prescribing rituximab in patients with hypogammaglobulinemia acquired in the setting of autoimmune diseases

We conducted a single-centre retrospective cohort study in a French University Hospital between 2010 and 2018 to describe the risk of severe infectious event (SIE) within 2 years after the date of first rituximab infusion (T0) prescribed after the evidence of acquired hypogammaglobulinemia (gamma globulins [GG] ≤ 6 g/L) in the setting of autoimmune diseases (AID) other than rheumatoid arthritis. SIE occurred in 26 out of 121 included patients. Two years cumulative incidence rates were 12.7 % (95 % CI 5.1-23.9) in the multiple sclerosis/neuromyelitis optica spectrum disorder group (n = 48), 27.6 % (95 % CI 15.7-40.9) in the ANCA-associated vasculitis group (n = 48) and 30.6 % (95 % CI 13.1-50.3) in the 'other AID' group (n = 25). Median GG level at T0 was 5.3 g/l (IQR 4.1-5.6) in the 'SIE' group and 5.6 g/l (IQR 4.7-5.8) in the 'no SIE' group (p = 0.04). In regression analysis, risk of SIE increased with Charlson comorbidity index ≥ 3 (OR 2.77; 95 % CI 1.01-7.57), lung disease (OR 3.20; 95 % CI 1.27-7.99), GG < 4 g/L (OR 3.39; 95 % CI 1.02-11.19), concomitant corticosteroid therapy (OR 4.13; 95 % CI 1.63-10.44), previous cyclophosphamide exposure (OR 2.69; 95 % CI 1.10-6.61), a lymphocyte count < 1000 cells/µL (OR 2.86; 95 % CI 1.12-7.21) and absence of pneumococcal vaccination (OR 3.50; 95 % CI 1.41-8.70). These results may help to inform clinical decision when considering a treatment by rituximab in immunosuppressed AID patients with hypogammaglobulinemia.

Real-life drug retention rate and safety of rituximab when treating rheumatic diseases: a single-centre Swiss retrospective cohort study

BACKGROUND

In Switzerland, rituximab (RTX) is licenced for the treatment of rheumatoid arthritis (RA) and ANCA-associated vasculitis (AAV) but is frequently used off-label to treat other auto-immune diseases (AID), especially connective tissue diseases (CTD). We aimed to characterise the use of RTX in AID in a real-life Swiss setting and compare RTX retention rates and safety outcomes between patients treated for RA, CTD and AAV.

METHODS

A retrospective cohort study of patients who started RTX in the Rheumatology Department for RA or AID. The RTX retention rate was analysed using Kaplan-Meier survival curves. Occurrences of serious adverse events (SAE), low IgG levels and anti-drug antibodies (ADA) were reported.

RESULTS

Two hundred three patients were treated with RTX: 51.7% had RA, 29.6% CTD, 9.9% vasculitis and 8.9% other AIDs. The total observation time was 665 patient-years. RTX retention probability at 2 years (95%CI) was similar for RA and CTD 0.65 (0.55 to 0.73), 0.60 (0.47 to 0.72) and lower for vasculitis 0.25 (0.09 to 0.45). Survival curves for RTX retention matched closely (p = 0.97) between RA and CTD patients but were lower for patients with vasculitis due to a higher percentage of induced remission. Patients with vasculitis (95%) and CTD (75%) had a higher rate of concomitant glucocorticoid use than RA (60%). Moderate to severe hypogammaglobulinaemia was observed more frequently in patients with vasculitis (35%) than with RA (13%) or CTD (9%) and was associated with an increased risk of presenting a first infectious SAE (HR 2.01, 95% CI 1.04 to 3.91). The incidence rate of SAE was 23.3 SAE/100 patient-years (36% were infectious). When searched, ADAs were observed in 18% of the patients and were detected in 63% of infusions-related SAE. 10 patients died during RTX treatment and up to 12 months after the last RTX infusion, 50% from infection.

CONCLUSION

RTX retention rates are similar for patients with RA and CTD but lower for those with vasculitis due to more frequent remission. Patients treated with RTX for vasculitis present more SAE and infectious SAE than patients with RA and CTD, potentially due to a higher use of concomitant glucocorticoids and the occurrence of hypogammaglobulinaemia.

Impact of extended interval dosing of ocrelizumab on immunoglobulin levels in multiple sclerosis

BACKGROUND

Long-term B cell depletion with ocrelizumab in multiple sclerosis (MS) is associated with severe side effects such as hypogammaglobulinemia and infections. Our study therefore aimed to assess immunoglobulin levels under treatment with ocrelizumab and implement an extended interval dosing (EID) scheme.

METHODS

Immunoglobulin levels of 51 patients with ≥24 months of treatment with ocrelizumab were analyzed. After ≥4 treatment cycles, patients chose to either continue on the standard interval dosing (SID) regimen (n = 14) or, in the case of clinically and radiologically stable disease, switch to B cell-adapted EID (n = 12, next dose at CD19⁺ B cells >1% of peripheral blood lymphocytes).

FINDINGS

Levels of immunoglobulin M (IgM) declined rapidly under ocrelizumab treatment. Risk factors for IgM and IgA hypogammaglobulinemia were lower levels at baseline and more previous disease-modifying therapies. B cell-adapted EID of ocrelizumab increased the mean time until next infusion from 27.3 to 46.1 weeks. Ig levels declined significantly in the SID group over 12 months but not in the EID group. Previously stable patients remained stable under EID as measured by expanded disability status scale (EDSS), neurofilament light chain, timed 25-foot walk (T25-FW), 9-hole peg test (9-HPT), symbol digit modalities test (SDMT), and multiple sclerosis impact scale (MSIS-29).

CONCLUSIONS

In our pilot study, B cell-adapted EID of ocrelizumab prevented the decline of Ig levels without affecting disease activity in previously stable patients with MS. Based on these findings, we propose a new algorithm for long-term ocrelizumab treatment.

FUNDING

This study was supported by the Deutsche Forschungsgemeinschaft (SFB CRC-TR-128, SFB 1080, and SFB CRC-1292) and the Hertie Foundation.

Current evidence of rituximab in the treatment of multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disorder of the central nervous system. The immunopathology of MS involves both T and B lymphocytes. Rituximab is one of the anti-CD20 monoclonal antibody therapies which deplete B-cells. Although some anti-CD20 therapies have been approved by the Food and Drug Administration for treatment of MS, rituximab is used off-label. Several studies have shown that rituximab has a good efficacy and safety in MS, including certain specific patient conditions such as treatment-naïve patients, treatment-switching patients, and the Asian population. However, there are still questions about the optimal dose and duration of rituximab in MS due to the different dosing regimens used in each study. Moreover, many biosimilars have become available at a lower cost with comparable physicochemical properties, pharmacokinetics, pharmacodynamics, efficacy, safety, and immunogenicity. Thus, rituximab may be considered as a potential therapeutic option for patients without access to standard treatment. This narrative review summarized the evidence of both original and biosimilars of rituximab in MS treatment including pharmacokinetics, pharmacodynamics, clinical efficacy, safety, and dosing regimen.

Low mortality rate in a large cohort of myelin oligodendrocyte glycoprotein antibody disease (MOGAD)

The mortality rates of individuals with myelin oligodendrocyte glycoprotein antibody disease (MOGAD) are currently unknown. This study aimed to assess the mortality rate in a large cohort of patients with MOGAD. Since none of the patients in our cohort died, we estimated the upper limit of a 95% confidence interval of the crude mortality rate in the cohort to be 2.1%. These data suggest that mortality in MOGAD is lower than that reported in other neuroinflammatory diseases and comparable to the age-adjusted mortality rates of the general population in the United States. Additional studies are warranted to confirm this observation.

Hypogammaglobulinemia secondary to B-cell depleting therapies in neuroimmunology: Comparing management strategies

Background

Anti-CD20 agents are commonly used in MS, NMOSD, and MOGAD. Few studies have compared strategies to address hypogammaglobulinemia.

Objective

To compare strategies to manage secondary hypogammaglobulinemia in neuroimmunology patients, including reducing anti-CD20 dose and dosing frequency, IVIG/SCIG, anti-CD20 cessation, and DMT switches.

Methods

All MS, NMOSD, and MOGAD patients at our institution with hypogammaglobulinemia on anti-CD20 agents from 2001 to 2022 were analyzed. The median change in IgG, infection frequency, and infection severity before and after the treatment was calculated.

Results

In total, 257 patients were screened, and 30 had a treatment for hypogammaglobulinemia. IVIG/SCIG yielded the largest increase in IgG per year (674.0 mg/dL), followed by B-cell therapy cessation (34.7 mg/dL), and DMT switch (5.9 mg/dL). Dose reduction had the largest decrease in yearly infection frequency (2.7 fewer infections), followed by IVIG/SCIG (2.5 fewer), DMT switch (2 fewer), and reduced dosing frequency (0.5 fewer). Infection grade decreased by 1.9 for reduced dosing frequency (less severe infections), by 1.3 for IVIG/SCIG, and by 0.6 for DMT switch.

Conclusion

This data suggests that IVIG/SCIG may yield the greatest recovery in IgG while also reducing infection frequency and severity. Stopping anti-CD20 therapy and/or switching DMTs also increase IgG and may lower infection risk.

Predictors of hospitalization due to infection in rituximab-treated MS patients

BACKGROUND

Rituximab is extensively used off-label to treat multiple sclerosis (MS), and long-term vigilance for adverse events is needed. This study was conducted to determine frequencies and predictors of hematological adverse events, including hypogammaglobulinemia, severe lymphopenia, neutropenia, and infections leading to hospitalization.

METHODS

This retrospective cohort study included all patients with MS initiating rituximab treatment at Haukeland University Hospital between January 1^st, 2017, and July 1^st, 2021. Patients were followed by clinical monitoring and repeated blood sampling every six months. Clinical outcomes and laboratory results were retrieved from the Norwegian MS Registry and Biobank and the patient administrative system at Haukeland University Hospital.

RESULTS

Five hundred and fifty-six patients were included, 515 with relapsing-remitting MS (RRMS) and 41 with progressive MS. Overall, 33 patients (5.9%) experienced 56 episodes of infections requiring hospital admission. Sixty patients (10.8%) had confirmed hypogammaglobulinemia, 17 (3.1%) had confirmed severe lymphopenia, and 10 (1.8%) had confirmed severe neutropenia. Predictors of infection requiring hospital admission were progressive MS (adjusted OR (aOR): 4.81; 95%CI: 1.25-18.48), duration of treatment with rituximab (aOR: 1.52; 95%CI: 1.11-2.09) and confirmed severe lymphopenia (aOR: 13.58; 95%CI: 3.41-54.06) and neutropenia (aOR: 13.40; 95%CI: 2.93-61.25). Of the hematological abnormalities, only hypogammaglobulinemia was associated with treatment duration (aOR: 1.35; 95%CI: 1.09-1.69).

CONCLUSION

The risk of hospitalization due to infection is associated with time on rituximab treatment, in patients with lympho- or neutropenia, and in patients with primary progressive MS. We observed a time-dependent decline in IgG values, in contrast to neutrophil and lymphocyte count, suggesting a cumulative dose-dependent response. These predictors can assist clinicians in assessing and monitoring MS patients receiving rituximab.

It's not always an infection: Pyoderma gangrenosum of the urogenital tract in two patients with multiple sclerosis treated with rituximab

B-cell depleting therapies such as rituximab and ocrelizumab are widely used for the treatment of Multiple Sclerosis but have increased risks of adverse reactions compared to earlier MS therapies. One rarely reported reaction is pyoderma gangrenosum (PG), an inflammatory, ulcerative, skin disease of unclear etiology. Here we describe a male and female patient, each with Relapsing-Remitting Multiple Sclerosis, and both of whom developed PG while on rituximab. Both PG diagnoses were supported by persistent fever, biopsy reports of sterile neutrophilia, and leukocytosis in the absence of an identifiable infectious agent. The diagnoses were further confirmed by dramatic clinical improvement following initiation of high dose steroids and intravenous immunoglobulins, and discontinuation of rituximab.

Sustained Low Relapse Rate With Highly Variable B-Cell Repopulation Dynamics With Extended Rituximab Dosing Intervals in Multiple Sclerosis

BACKGROUND AND OBJECTIVES

B cell-depleting therapies are highly effective in relapsing-remitting multiple sclerosis (RRMS) but are associated with increased infection risk and blunted humoral vaccination responses. Extension of dosing intervals may mitigate such negative effects, but its consequences on MS disease activity are yet to be ascertained. The objective of this study was to determine clinical and neuroradiologic disease activity, as well as B-cell repopulation dynamics, after implementation of extended rituximab dosing in RRMS.

METHODS

We conducted a prospective observational study in a specialized-care, single-center setting, including patients with RRMS participating in the COMBAT-MS and MultipleMS observational drug trials, who had received at least 2 courses of rituximab (median follow-up 4.2 years, range 0.1-8.9 years). Using Cox regression, hazard ratios (HRs) of clinical relapse and/or contrast-enhancing lesions on MRI were calculated in relation to time since last dose of rituximab.

RESULTS

A total of 3,904 dose intervals were accumulated in 718 patients and stratified into 4 intervals: <8, ≥8 to 12, ≥12 to 18, and ≥18 months. We identified 24 relapses of which 20 occurred within 8 months since previous infusion and 4 with intervals over 8 months. HRs for relapse when comparing ≥8 to 12, ≥12 to 18, and ≥18 months with <8 months since last dose were 0.28 (95% CI 0.04-2.10), 0.38 (95% CI 0.05-2.94), and 0.89 (95% CI 0.20-4.04), respectively, and thus nonsignificant. Neuroradiologic outcomes mirrored relapse rates. Dynamics of total B-cell reconstitution varied considerably, but median total B-cell counts reached lower level of normal after 12 months and median memory B-cell counts after 16 months.

DISCUSSION

In this prospective cohort of rituximab-treated patients with RRMS exposed to extended dosing intervals, we could not detect a relation between clinical or neuroradiologic disease activity and time since last infusion. Total B- and memory B-cell repopulation kinetics varied considerably. These findings, relevant for assessing risk-mitigation strategies with anti-CD20 therapies in RRMS, suggest that relapse risk remains low with extended infusion intervals. Further studies are needed to investigate the relation between B-cell repopulation dynamics and adverse event risks associated with B-cell depletion.

Characterisation of the safety profile of evobrutinib in over 1000 patients from phase II clinical trials in multiple sclerosis, rheumatoid arthritis and systemic lupus erythematosus: an integrated safety analysis

OBJECTIVE

Analyse the integrated safety profile of evobrutinib, a Bruton's tyrosine kinase inhibitor (BTKi), using pooled data from multiple sclerosis (MS), rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) trials.

METHODS

Phase II, randomised, double-blind, placebo-controlled trial data were analysed (N=1083; MS: n=213, 48 weeks (W); RA: n=390, 12W; SLE: n=480, 52W). The analysis included all patients who received ≥1 dose of evobrutinib (25 mg or 75 mg once daily, or 50 mg or 75 mgtwice daily) or placebo. Descriptive statistics and exposure-adjusted incidence rates (EAIR) were used to report treatment-emergent adverse events (TEAEs).

RESULTS

Data from 1083 patients were pooled: evobrutinib, n=861; placebo, n=271 (sum >1083 due to MS trial design: n=49 received both placebo (W0-24) and evobrutinib 25 mg (W25-48)); median follow-up time (pt-years): evobrutinib, 0.501; placebo, 0.463. Across indications, the proportion of patients with TEAEs and the EAIR were similar for evobrutinib and placebo (66.2% (247.6 events/100 pt-years) vs 62.4% (261.4 events/100 pt-years)). By indication, the EAIR (events/100 pt-years) of TEAEs for evobrutinib versus placebo were: MS: 119.7 vs 148.3; RA: 331.8 vs 306.8; SLE: 343.0 vs 302.1. Two fatal events occurred (in SLE). The serious infections EAIR was 2.7 and 2.1 events/100 pt-years for evobrutinib and placebo. For previously reported BTKi-class effects, the EAIR of transient elevated alanine aminotransferase/aspartate aminotransferase TEAEs (events/100 pt-years) with evobrutinib versus placebo was 4.8 vs 2.8/3.5 vs 0.7, respectively. IgG levels were similar in evobrutinib/placebo-treated patients.

CONCLUSIONS

This is the first BTKi-integrated safety analysis that includes patients with MS. Overall, evobrutinib treatment (all doses) was generally well tolerated across indications.

TRIAL REGISTRATION NUMBERS

NCT02975349, NCT03233230, NCT02975336.

Infection risk in a real-world cohort of patients treated with long-term B-cell depletion for autoimmune neurologic disease

BACKGROUND

B-cell depleting medications are effective disease-modifying therapies for multiple sclerosis. Prior studies have demonstrated that use of these medication is associated with infections and immunologic changes. Limited data suggest that infectious adverse effects may be more common with long-term use. We aimed to investigate rates of infections and laboratory abnormalities in a real-world cohort of patients treated with long term B-cell depletion and identify clinical factors associated with these outcomes.

METHODS

In this retrospective, single-center observational study, patients with MS and other autoimmune neurologic disorders treated with rituximab or ocrelizumab for ≥2 years were identified. Linear regression analyses identified factors associated with increased risk of minor and severe infections. Rates of total and severe infections were compared between the first two years of treatment and years three and beyond.

RESULTS

291 patients, treated with rituximab or ocrelizumab for an average of 46 months, were included. Total infections and infections requiring hospitalization occurred at rates of 25.0 and 3.03 per 100 person-years, respectively. Female gender and current or former smoking status were associated with a higher rate of total infections. Hypogammaglobulinemia and higher BMI were associated with increased risk of hospitalization. Rates of total and serious infections were higher in years three and beyond compared to the first two years.

CONCLUSIONS

Infections in patients with MS treated with long-term B-cell depletion may be more common with longer duration of therapy. This study provides additional information to help personalize care.

Neutropenia complicating anti-CD20 treatment in patients with multiple sclerosis: A retrospective case series and a systematic review of reported cases

BACKGROUND

Neutropenia is an infrequent complication of treatment with CD20 depleting agents and may require the administration of granulocyte-colony stimulating factors (G-CSF), which have been associated with an increased relapse risk in patients with multiple sclerosis (PwMS). The management of this side effect is still matter of debate.

METHODS

Aim of this study is to evaluate the clinical features and the management of neutropenia occurring in anti-CD20 treated PwMS through a single-center case series and a systematic review of the literature, performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

A total of 19 patients were included (3 from our clinical experience, 16 from the systematic review). Median age was 38 years-old (25-69) and nearly 70% were female, most of these patients had already received a median of 3 (0-4) previous treatments. Neutropenia occurred in 11 patients treated with ocrelizumab and 8 with rituximab, after a median of 2 (1-7) infusions and 9.5 (1-42) months from the first infusion. Most of these patients had late-onset neutropenia, that occurred after a median time of 90 days (2-156). About 70% of patients were symptomatic and most were treated with G-CSF or antibiotics. No relapses after G-CSF were reported. In those who did not suspend anti-CD20 (68.8%), neutropenia reoccurred in 18.2% of cases. Finally, switching between rituximab and ocrelizumab seem not to affect the occurrence of neutropenia.

CONCLUSION

Our data provides practical evidence regarding the occurrence and the management of neutropenia during treatment with anti-CD20 in PwMS.

Secondary rituximab-associated versus primary immunodeficiencies: The enigmatic border

Rituximab (RTX), a chimeric monoclonal antibody targeting CD20-positive cells, is a valuable treatment option for malignant and benign immune-related disorders. The rationale of targeting the CD20 antigen relies on depletion of both healthy and autoreactive/malignant CD20-espressing cells, but normal B-cell reconstitution is expected within months after treatment. Nevertheless, a number of recent studies have documented prolonged B-cell deficiency associated with new-onset hypogammaglobulinemia in patients receiving RTX. Awareness of post-RTX hypogammaglobulinemia has become wider among clinicians, with a growing number of reports about the increased incidence, especially in children. Although these patients were previously regarded as affected by secondary/iatrogenic immunodeficiency, atypical clinical and immunological manifestations (e.g., severe or opportunistic infections; prolonged B-cell aplasia) raise concerns of delayed manifestations of genetic immunological disorders that have been unveiled by B-cell perturbation. As more patients with undiagnosed primary immune deficiency receiving RTX have been identified, it remains the challenge in discerning those that might display a higher risk of persistent RTX-associated hypogammaglobulinemia and need a tailored immunology follow-up. In this review, we summarize the principal evidence regarding post-RTX hypogammaglobulinemia and provide a guideline for identifying patients at higher risk of RTX-associated hypogammaglobulinemia that could harbor an inborn error of immunity.

Rituximab-Induced Hypogammaglobulinemia and Risk of Infection in Neuromyelitis Optica Spectrum Disorders

Background and Objectives

To investigate the frequency and predictors of hypogammaglobulinemia during long-term rituximab (RTX) treatment in patients with neuromyelitis optica spectrum disorder (NMOSD) and its association with infections.

Methods

We retrospectively reviewed the data of patients with NMOSD who received RTX through the maintenance regimen based on memory B-cell detection for at least 1 year from 2006 to 2021 at an institutional referral center for NMOSD.

Results

A total of 169 patients received a median of 10 courses (range 1–27) of RTX reinfusion after induction over a median of 8 (range, 1–15) years. Their mean serum immunoglobulin (Ig)G level began to decline significantly after 2 years of treatment, steadily declined at a rate of 2%–8% per year for the following 8 years, and then plateaued after 10 years. The proportion of patients with hypo-IgG (<6 g/L) increased from 1.2% after 1 year of treatment to 41% after 14 years of treatment. While being treated with RTX, 58 (34%) patients had 114 infections, of whom 14 (8%) patients had 15 severe infections. Multivariable logistic regression analyses identified duration of RTX treatment in years (odds ratio [OR] 1.234, 95% confidence interval [CI] 1.015–1.502), mean annual RTX dose (OR 0.063, 95% CI 0.009–0.434), history of mitoxantrone (OR 3.318, 95% CI 1.109–9.93), hypo-IgG at baseline (OR 40.552, 95% CI 3.024–543.786), and body mass index >25 kg/m² (OR 4.798, 95% CI 1.468–15.678) as independent predictors of hypo-IgG. The risk of infection during RTX treatment was independently associated with high Expanded Disability Status Scale scores (OR 1.427, 95% CI 1.2–1.697) and relapses during RTX treatment (OR 1.665, 95% CI 1.112–2.492), but not with hypogammaglobulinemia.

Discussion

Over 14 years of long-term RTX treatment, IgG levels gradually decreased, and the frequency of hypo-IgG increased to 41% of the patients. Patients with prolonged memory B-cell depletion after RTX, previous mitoxantrone history, hypo-IgG at baseline, or obesity were at risk of developing RTX-induced hypogammaglobulinemia. Nevertheless, infection rates remained low during treatment, and reduced immunoglobulin levels were not associated with an increased incidence of infections.

The prevalence of cancer in patients with multiple sclerosis (MS) who received rituximab: a systematic review and meta-analysis

OBJECTIVE

To estimate the pooled prevalence of cancer in patients with multiple sclerosis (MS) cases who were under treatment with rituximab.

METHODS

We searched PubMed, Scopus, EMBASE, Web of Science, and google scholar along with gray literature up to April 2021. The search strategy included the MeSH and text words as (("CD20 Antibody" AND Rituximab) OR "Rituximab CD20 Antibody" OR Mabthera OR "IDEC-C2B8 Antibody" OR "IDEC C2B8 Antibody" OR IDEC-C2B8 OR "IDEC C2B8" OR GP2013 OR Rituxan OR rituximab) AND ((Sclerosis AND multiple) OR (sclerosis AND disseminated) OR "disseminated sclerosis" OR "multiple sclerosis" OR "acute fulminating").

RESULTS

The literature search revealed 3577 articles, after deleting duplicates 2066 remained. For the meta-analysis, 22 studies were included. Totally, 15599 patients were enrolled while 133 cancers were detected. The pooled prevalence of cancer in MS patients under treatment with rituximab is 1in 100,000 (I2 = 99.9%, p < 0.001).

CONCLUSION

The results of this systematic review and meta-analysis show that the pooled prevalence of cancer in MS patients who received rituximab is 1 in 100,000 cases.

Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease (MOGAD): A Review of Clinical and MRI Features, Diagnosis, and Management

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is the most recently defined inflammatory demyelinating disease of the central nervous system (CNS). Over the last decade, several studies have helped delineate the characteristic clinical-MRI phenotypes of the disease, allowing distinction from aquaporin-4 (AQP4)-IgG-positive neuromyelitis optica spectrum disorder (AQP4-IgG+NMOSD) and multiple sclerosis (MS). The clinical manifestations of MOGAD are heterogeneous, ranging from isolated optic neuritis or myelitis to multifocal CNS demyelination often in the form of acute disseminated encephalomyelitis (ADEM), or cortical encephalitis. A relapsing course is observed in approximately 50% of patients. Characteristic MRI features have been described that increase the diagnostic suspicion (e.g., perineural optic nerve enhancement, spinal cord H-sign, T2-lesion resolution over time) and help discriminate from MS and AQP4+NMOSD, despite some overlap. The detection of MOG-IgG in the serum (and sometimes CSF) confirms the diagnosis in patients with compatible clinical-MRI phenotypes, but false positive results are occasionally encountered, especially with indiscriminate testing of large unselected populations. The type of cell-based assay used to evaluate for MOG-IgG (fixed vs. live) and antibody end-titer (low vs. high) can influence the likelihood of MOGAD diagnosis. International consensus diagnostic criteria for MOGAD are currently being compiled and will assist in clinical diagnosis and be useful for enrolment in clinical trials. Although randomized controlled trials are lacking, MOGAD acute attacks appear to be very responsive to high dose steroids and plasma exchange may be considered in refractory cases. Attack-prevention treatments also lack class-I data and empiric maintenance treatment is generally reserved for relapsing cases or patients with severe residual disability after the presenting attack. A variety of empiric steroid-sparing immunosuppressants can be considered and may be efficacious based on retrospective or prospective observational studies but prospective randomized placebo-controlled trials are needed to better guide treatment. In summary, this article will review our rapidly evolving understanding of MOGAD diagnosis and management.

Confirming a Historical Diagnosis of Multiple Sclerosis: Challenges and Recommendations

Patients with a historical diagnosis of multiple sclerosis (MS)-a patient presenting with a diagnosis of MS made previously and by a different clinician-present specific diagnostic and therapeutic challenges in clinical practice. Application of the McDonald criteria is most straightforward when applied contemporaneously with a syndrome typical of an MS attack or relapse; however, retrospective application of the criteria in some patients with a historical diagnosis of MS can be problematic. Limited patient recollection of symptoms and evolution of neurologic examination and MRI findings complicate confirmation of an earlier MS diagnosis and assessment of subsequent disease activity or clinical progression. Adequate records for review of prior clinical examinations, laboratory results, and/or MRI scans obtained at the time of diagnosis or during ensuing care may be inadequate or unavailable. This article provides recommendations for a clinical approach to the evaluation of patients with a historical diagnosis of MS to aid diagnostic confirmation, avoid misdiagnosis, and inform therapeutic decision making.

MRI and laboratory monitoring of disease-modifying therapy efficacy and risks

PURPOSE OF REVIEW

Increasingly, therapeutic strategy in multiple sclerosis (MS) is informed by imaging and laboratory biomarkers, in addition to traditional clinical factors. Here, we review aspects of monitoring the efficacy and risks of disease-modifying therapy (DMT) with both conventional and emerging MRI and laboratory measures.

RECENT FINDINGS

The adoption of consensus-driven, stable MRI acquisition protocols and artificial intelligence-based, quantitative image analysis is heralding an era of precision monitoring of DMT efficacy. New MRI measures of compartmentalized inflammation, neuro-degeneration and repair complement traditional metrics but require validation before use in individual patients. Laboratory markers of brain cellular injury, such as neurofilament light, are robust outcomes in DMT efficacy trials; their use in clinical practice is being refined. DMT-specific laboratory monitoring for safety is critical and may include lymphocytes, immunoglobulins, autoimmunity surveillance, John Cunningham virus serology and COVID-19 vaccination seroresponse.

SUMMARY

A biomarker-enhanced monitoring strategy has immediate clinical application, with growing evidence of long-term reductions in disability accrual when both clinically symptomatic and asymptomatic inflammatory activity is fully suppressed; and amelioration of the risks associated with therapy. Emerging MRI and blood-based measures will also become important tools for monitoring agents that target the innate immune system and promote neuro-repair.

Hypogammaglobulinemia, infections and COVID-19 in people with multiple sclerosis treated with ocrelizumab

Objective

To determine the influence of immunoglobulins (Ig) level on the rate of infections in people with multiple sclerosis (pwMS) treated with ocrelizumab.

Methods

We enrolled 109 consecutive pwMS treated with ocrelizumab with a mean follow-up of 2.69±0.56 (1.36-4.27) years. We have retrospectively searched our electronic database and the following information was collected: age, sex, MS characteristics, number of ocrelizumab cycles, infections, duration of the infection, hospitalization due to infection, treatment of the infection, and COVID-19 characteristics. Ig levels were measured within 14 days before each ocrelizumab infusion.

Results

Number of pwMS with values of IgM and IgG below lower level of normal at baseline was 3 (2.8%) and 2 (2.8%), respectively; and before 6^th cycle of ocrelizumab 5 (13.5%) and 5 (13.5%), respectively. Levels of IgM were steadily decreasing over time, while levels of IgG started to show statistically significant drop only after 5^th cycle of ocrelizumab. 58.7% pwMS experienced infection during treatment, with a median number of infections per pwMS being 1, range 0-4. Female sex increased the risk of any infection (HR 2.561, 95%CI 1.382-4.774, p=0.003). Higher age and smaller drop in IgM before 3^rd ocrelizumab cycle increased the risk for infection requiring hospitalization (HR 1.086, 95%CI 1.018-1.159, p=0.013 and HR 9.216, 95%CI 1.124-75.558, p=0.039, respectively). Longer disease duration increased the risk for COVID-19 (HR 1.075, 95%CI 1.002-1.154, p=0.045).

Conclusion

The present findings broaden limited real-world data on infection and COVID-19 risk in pwMS treated with ocrelizumab.

Evolution of Disease Modifying Therapy Benefits and Risks: An Argument for De-escalation as a Treatment Paradigm for Patients With Multiple Sclerosis

Background

Strategies for sequencing disease modifying therapies (DMTs) in multiple sclerosis (MS) patients include escalation, high efficacy early, induction, and de-escalation.

Objective

To provide a perspective on de-escalation, which aims to match the ratio of DMT benefit/risk in aging patients.

Methods

We reanalyzed data from a retrospective, real-world cohort of MS patients to model disease activity for oral (dimethyl fumarate and fingolimod) and higher efficacy infusible (natalizumab and rituximab) DMTs by age. For patients with relapsing MS, we conducted a controlled, stratified analysis examining odds of disease activity for oral vs. infusible DMTs in patients &lt;45 or ≥45 years. We reviewed the literature to identify DMT risks and predictors of safe discontinuation.

Results

Younger patients had lower probability of disease activity on infusible vs. oral DMTs. There was no statistical difference after age 54.2 years. When dichotomized, patients &lt;45 years on oral DMTs had greater odds of disease activity compared to patients on infusible DMTs, while among those ≥45 years, there was no difference. Literature review noted that adverse events increase with aging, notably infections in patients with higher disability and longer DMT duration. Additionally, we identified factors predictive of disease reactivation including age, clinical stability, and MRI activity.

Conclusion

In a real-world cohort of relapsing MS patients, high efficacy DMTs had less benefit with aging but were associated with increased risks. This cohort helps overcome some limitations of trials where older patients were excluded. To better balance benefits/risks, we propose a DMT de-escalation approach for aging MS patients.

Tolerability and Safety of Switching from Rituximab to Ocrelizumab: Evaluating Factors Associated with Infusion Related Reactions

Background

Ocrelizumab and rituximab are frequently used treatments for multiple sclerosis (MS). Data on switching from rituximab to ocrelizumab is limited.

Objectives

To assess the frequency, severity, and factors of infusion related reactions (IRRs) in patients with MS who switch from rituximab to ocrelizumab, compared to those who stay on rituximab.

Methods

Prospective study on MS patients aged 18–65, on rituximab for at least 2 cycles, who either switched to ocrelizumab (switch group) or stayed on rituximab (comparator group) (n = 100 each). Participants were followed for IRRs, safety, and tolerability over 12 months.

Results

The proportion of IRRs in patients who continue on rituximab (14%) were similar to those who switched to ocrelizumab on Day 1 (14%; p = 1.000) and Week 24 (12%; p = 0.647) but higher than at Day 15 (4%; 0.005). The risk of IRRs for the switch group was associated with the presence of B cells (CD19 and/or CD20 counts ≥1%) increasing by 5.01 (1.49, 16.82) times on Day 1 (p = 0.007). Antidrug antibodies to ocrelizumab were not associated with IRRs. No other safety concerns were identified in switching to ocrelizumab.

Conclusion

IRRs are similar between both groups, which suggests that it is safe to switch from rituximab to ocrelizumab.

Hypogammaglobulinemia and Infections in Patients With Multiple Sclerosis Treated With Rituximab

BACKGROUND AND OBJECTIVES

To determine the frequency of hypogammaglobulinemia and infections in patients with multiple sclerosis (PwMS) receiving rituximab (RTX).

METHODS

This prospective observational study included all consecutive PwMS receiving RTX at the university hospital of Marseille, France, between 2015 and 2020. Patient visits occurred at least every 6 months.

RESULTS

We included 188 patients (151 with relapsing-remitting MS; the mean age was 43.4 years [SD 12.9], median disease duration 10 years [range 0-36], median Expanded Disability Status Scale 5 [range 0-8], median follow-up 3.5 years [range 1-5.8], and median number of RTX infusions 5 [range 1-9]). Overall, 317 symptomatic infections and 13 severe infections occurred in 133 of 188 (70.7%) and 11 of 188 (5.9%) patients, respectively. After 4 years, 24.4% of patients (95% CI 18.0-33.1) were free of any infection and 92.0% (95% CI 87.1-97.1) had not experienced a severe infection. At RTX onset, the immunoglobulin G (IgG) level was abnormal in 32 of 188 (17%) patients. After RTX, IgG level was <7, <6, <4 and <2 g/L for 83 (44%), 44 (23.4%), 8 (4.2%) and 1 (0.53%) patients, respectively. The risk of infection was associated with reduced IgG levels (multivariate Cox proportional hazards hazard ratio [HR] = 0.86, 95% CI 0.75-0.98, p = 0.03). The risk of reduced IgG level <6 g/L increased with age (HR = 1.36, 95% CI 1.05-1.75, p = 0.01).

DISCUSSION

In PwMS receiving RTX, reduced IgG level was frequent and interacted with the risk of infection.

Derisking CD20-therapies for long-term use

Anti-CD20 have quickly become the mainstay in the treatment of multiple sclerosis (MS) and other neuroinflammatory conditions. However, when they are used as a maintenance therapy the balance between risks and benefits changes. In this review, we suggested six steps to derisk anti-CD20. Firstly and secondly, adequate infectious screening followed by vaccinations before starting anti-CD20 are paramount. Third, family planning needs to be discussed upfront with every woman of childbearing age. Fourth, infusion reactions should be adequately managed to avoid treatment interruption. After repeated infusions, it becomes important to detect and prevent anti-CD20-related adverse events. Fifth, we recommended measuring immunoglobulin levels and reviewing vaccinations annually as well as counselling adequate fever management. For female patients, we emphasised the importance to engage with the local breast cancer screening programs. Sixth, to fundamentally derisk anti-CD20 therapies, we need evidence-based approaches to reduce dosing intervals and guide retreatment.