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

Real-world observational study of infections in people treated with ocrelizumab for multiple sclerosis

BACKGROUND

Anti-CD20 monoclonal antibodies are now a common first-line treatment for multiple sclerosis (MS). Rituximab, ocrelizumab and ofatumumab have all been associated with a dose-dependent risk of hypogammaglobulinaemia, but its relevance in clinical practice remains uncertain.

OBJECTIVES

To study infection rates over time in a real-world cohort of people treated with ocrelizumab for MS, and their relationship to serum immunoglobulin.

DESIGN

Observational study of 152 people receiving ocrelizumab for MS followed for up to 5.6 years (mean 2.7 years).

RESULTS

Mean (SD) annualized changes in immunoglobulins during ocrelizumab treatment were IgM - 0.22 g/L/year (0.4), IgG - 0.38 g/L/year (0.9), IgA - 0.03 g/L/year. Rates of self-reported infection increased significantly during the first 4 years of treatment. Infection rates were not only associated with total immunoglobulin levels but also independently associated with age, comorbidity and female sex. We demonstrated for the first time that 29 out of 34 (87%) people on ocrelizumab with IgG in the lower normal range had sub-protective antibody responses to pneumococcus / haemophilus influenzae.

CONCLUSIONS

Real-world observational studies complement open label extensions of clinical trials, often by having a more representative cohort and more complete follow-up. Our data suggest that while serious infections are rare in people on ocrelizumab, non-serious infections become increasingly burdensome. We offer practical suggestions on mitigating the risk of infection on ocrelizumab and other anti-CD20 medications.

Comprehensive analysis of B cell repopulation in ocrelizumab-treated patients with multiple sclerosis by mass cytometry and proteomics

Ocrelizumab, an anti-CD20 antibody, depletes CD20+ B cells, which subsequently repopulate over months. Little is known about changes in other immune cell populations and molecular markers associated with B cell repopulation. Here, we performed a comprehensive characterization of immune cells from ocrelizumab-treated patients with multiple sclerosis (MS) using mass cytometry. About 50% of patients showed naive B cell repopulation after 6 months mainly with a transitional phenotype, whereas CD27+ memory B cells only rarely repopulated. This repopulation was associated with a reduction of memory T cells and activated myeloid cells, as well as reduced expression of activation/migration markers in both cell types. A plasma proteomics analysis identified proteins including TNFRSF13C, associated with B cell depletion and repopulation. Plasma levels of neurofilament light-chain protein declined after ocrelizumab treatment was not linked with B cell repopulation. These findings identify potential soluble markers for monitoring of ocrelizumab treatment in MS.

Early extended interval dosing of rituximab in multiple sclerosis: A comparative cohort study on efficacy and safety

BACKGROUND

Rituximab is a highly effective disease modifying therapy for persons with MS (pwMS), but is associated with increased risk of infections. Due to the Covid-19 pandemic, St. Olavs Hospital (SOHO) in Trondheim, Norway, changed from the standard interval dosing (SID) of six months to extended interval dosing (EID) of nine months after the third infusion. At Haukeland University Hospital (HUS) in Bergen, Norway, SID was maintained. This study compares efficacy and safety measures of EID with SID at these two hospitals.

METHODS

In the Norwegian MS registry (NMSR), we identified pwMS aged 18-60 years who were followed at SOHO or HUS and started rituximab between October 2018 and June 2021. The patients had an initial period with similar 6-month dosing intervals, followed by a study period with different dosing intervals. They were followed until august 2023, or until deviating dosing intervals, discontinuation, or loss to follow up. We compared relapse rates, the occurrence of new magnetic resonance imaging (MRI) T2 lesions, and incidence rates of infections, IgG- hypogammaglobulinemia and severe neutropenia.

RESULTS

We included 78 pwMS from SOHO and 217 from HUS, with overall short disease duration (median 0.6 years at SOHO and 0.2 years at HUS) and similar baseline characteristics. We found no statistical significant differences in relapse rates (p >0.99), proportions with new T2 lesions (p = 0.69) or incidence rates of adverse events.

CONCLUSION

Our study suggests that early 9-month EID after the third infusion is a safe and effective treatment option for MS patients.

Clinical and radiological activity after extended interval and standard interval dosing of ocrelizumab in multiple sclerosis: A systematic review and meta-analysis

BACKGROUND

Ocrelizumab is an anti-CD20 monoclonal antibody that is highly effective in reducing MS clinical and radiological activity. The standard dosing regimen consists of infusing 600 mg of ocrelizumab every six months. However, concerns about increasing risks of infection and lowered vaccine response, particularly during the COVID-19 pandemic, prompted clinicians to extend the dosing interval between ocrelizumab infusions for some patients. Several observational studies have compared the effects of extended-interval dosing (EID) and standardinterval dosing (SID) of ocrelizumab on MS relapse rate and MRI activity.  METHOD: We performed a systematic review and meta-analysis of the current literature to summarize studies comparing ocrelizumab EID and SID on MS disease activity in patients with MS. Two independent reviewers searched PubMed, Scopus, EMBASE, Web of Science, and Google Scholar on the 1st of June 2024.

RESULTS

Our systematic search revealed 348 records, and after deleting duplicates, 29 records remained. Twenty-eight full texts were evaluated; ultimately, 16 studies remained for systematic review. In this meta-analysis, extended interval dosing (EID) was defined variably across studies, with some considering even a one-month delay as EID. The pooled odds ratios (ORs) for clinical and MRI activity, comparing ocrelizumab EID to SID groups, were estimated as 1.04 (95%CI: 0.67-1.6, I2=30%, P=0.21) and 1.31(95%CI: 0.90-1.92) (I2=15%, P=0.32), respectively.  CONCLUSION: This systematic review and meta-analysis suggest that ocrelizumab EID is not associated with greater odds of clinical and radiological disease activity in patients with MS.

Extended-interval dosing of rituximab/ocrelizumab is associated with a reduced decrease in IgG levels in multiple sclerosis

The potential benefits of extended-interval dosing (EID) of rituximab (RTX) or ocrelizumab (OCR) in mitigating the reduction of immunoglobulin levels and decreasing the risk of infection in persons with relapsing-remitting multiple sclerosis (pwRRMS) remain largely unknown. We retrospectively analyzed two structured data collections including pwRRMS who were prescribed RTX/OCR using different interval dosing regimens, a 6-month standard-interval dosing (SD) or EID. The SD and EID cohorts included 88 and 271 pwRRMS, respectively, with a mean (SD) treatment duration of 3.5 (1.3) and 4.4 (1.5) years, and a mean (SD) interval between infusions of 6.4 (1.7) and 19.2 (11.9) months. After RTX/OCR initiation, the two cohorts did not differ in time to first relapse (p ​= ​0.83), time to first sustained accumulation of disability (p ​= ​0.98) and incidence of MRI activity (p ​= ​0.91). The time to first severe infectious event (SIE) was shorter in the SD cohort (p ​= ​0.005). The effect of treatment duration on reduction of serum IgG level was lower in the EID cohort (Estimate ​= ​0.15 ​g/L per year of follow-up, 95 ​% CI -0.06, -0.23, p ​= ​0.001). In the entire patient group, higher serum IgG levels at the last infusion were associated with a lower risk of SIE between two visits (HR ​= ​0.77 per g/L of serum IgG; 95 ​% CI: 0.66-0.91; p ​= ​0.006). This study suggests that EID of RTX/OCR may reduce the risk of serum IgG decline in pwRRMS without a loss of efficacy and may mitigate the risk of severe infections. These results must be confirmed by future randomized studies.

Home-sampling of B cells using quantitative dried blood spots to enable tailored therapeutic re-dosing of anti-CD20 therapies

Anti-CD20 monoclonal antibodies are commonly used to manage neuroinflammatory diseases. The rate of B-cell re-emergence after dosing of ocrelizumab or rituximab varies considerably between individuals, but most people remain completely B-cell depleted at 6 months. Tailoring the dosing according to B-cell re-emergence may improve the safety profile of anti-CD20s but poses logistical challenges such as the need for regular attendances for whole-blood sampling. Here we combined a quantitative dried blood spot sampling technique with a DNA methylation test, to provide a reliable means of remotely monitoring B-cell counts, with 100% sensitivity and specificity for reaching >10 × 106 cells/L.

Comparing the efficacy and safety of extended vs standard dosing of ocrelizumab in MS: A systemic review and meta-analysis

INTRODUCTION

Multiple Sclerosis (MS) is a challenging autoimmune disease that disrupts the central nervous system, leading to a range of symptoms. Ocrelizumab, a treatment commonly used for MS, targets B cells to help manage the disease. While the standard-interval dosing (SID) is effective, the COVID-19 pandemic raised concerns about safety, particularly around immune responses. This prompted interest in extended-interval dosing (EID), which spaces out treatments more. Our study aims to compare how well EID works against SID and if it's safer for patients.

METHODS

We followed strict guidelines to review the research on EID and SID in MS patients. Using databases like PubMed and Scopus, we looked for studies up to July 2024. We included clinical trials and cohort studies that directly compared these dosing strategies. A team of reviewers collected data, assessed the quality of the studies, and performed statistical analysis to find any differences in effectiveness and safety.

RESULTS

Our analysis included 11 studies involving over 2,500 patients. We found that EID and SID were similarly effective in controlling disease activity (no significant difference in NEDA). However, patients on EID experienced fewer side effects, with significantly fewer adverse events compared to those on SID.

CONCLUSION

EID appears to be just as effective as SID in managing MS, but with the added benefit of reducing side effects. This makes EID a promising alternative for long-term treatment, offering patients a lighter treatment burden while maintaining disease control. More research is needed to explore its long-term impact.

Profiling of B cells and their subsets by whole blood gene expression analysis versus flow cytometry in multiple sclerosis

We investigated if differentially expressed mRNA targets could be used as surrogate markers for circulating B cells and subsets. In paired blood samples from patients with untreated, anti-CD20-treated, fingolimod-treated, and natalizumab-treated multiple sclerosis, whole blood expression of CD19 correlated with B cell counts determined by flow cytometry, ROR1 with transitional B cells, TCL1A and ZNF727 with naïve B cells, NEXMIF with memory B cells and BCMA with plasmablasts. CD19 expression distinguished patients with B cell repletion and may be used as an alternative to flow cytometry, but NEXMIF was unsuitable for memory B cell monitoring in rituximab-treated patients.

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.

Drugs Targeting CD20 in Multiple Sclerosis: Pharmacology, Efficacy, Safety, and Tolerability

Currently, there are four monoclonal antibodies (mAbs) that target the cluster of differentiation (CD) 20 receptor available to treat multiple sclerosis (MS): rituximab, ocrelizumab, ofatumumab, and ublituximab. B-cell depletion therapy has changed the therapeutic landscape of MS through robust efficacy on clinical manifestations and MRI lesion activity, and the currently available anti-CD20 mAb therapies for use in MS are a cornerstone of highly effective disease-modifying treatment. Ocrelizumab is currently the only therapy with regulatory approval for primary progressive MS. There are currently few data regarding the relative efficacy of these therapies, though several clinical trials are ongoing. Safety concerns applicable to this class of therapeutics relate primarily to immunogenicity and mechanism of action, and include infusion-related or injection-related reactions, development of hypogammaglobulinemia (leading to increased infection and malignancy risk), and decreased vaccine response. Exploration of alternative dose/dosing schedules might be an effective strategy for mitigating these risks. Future development of biosimilar medications might make these therapies more readily available. Although anti-CD20 mAb therapies have led to significant improvements in disease outcomes, CNS-penetrant therapies are still needed to more effectively address the compartmentalized inflammation thought to play an important role in disability progression.