Key characteristics of anti-CD20 monoclonal antibodies and clinical implications for multiple sclerosis treatment

The Evolution of Anti-CD20 Treatment for Multiple Sclerosis: Optimization of Antibody Characteristics and Function

B-cell depletion with CD20-targeted agents is commonly used for treatment of multiple sclerosis (MS), other autoimmune diseases, and certain hematologic malignancies. Initial apparent success with rituximab in MS and neuromyelitis optica spurred development of the anti-CD20 monoclonal antibody (mAb) therapies ocrelizumab, ofatumumab, and ublituximab as well as the anti-CD19 mAb inebilizumab. While each are effective at targeting and depleting B cells, structural differences translate into different mechanisms of action affecting maintenance of B-cell depletion and safety and tolerability. Although the anti-CD20 mAbs differ in degree of human versus mouse sequences as well as target CD20 epitope, these properties do not appear to substantially affect activity or tolerability. In contrast, an antibody-dependent cell-mediated cytotoxicity (ADCC) versus a complement-dependent cytotoxicity mechanism of action as well as subcutaneous versus intravenous administration may provide improved tolerability. Glycoengineering of the mAbs ublituximab and inebilizumab enhances ADCC and can overcome the reduced responses to mAb-mediated B-cell depletion associated with certain genetic polymorphisms. Other strategies for therapeutic targeting of CD20, including brain shuttle antibodies (e.g., RO7121932), bispecific antibodies, chimeric antigen receptor T-cell therapies, and antibody-drug conjugates, are in active clinical development and may be future treatment approaches in MS and other B-cell-mediated autoimmune diseases.

Hypogammaglobulinemia in patients with multiple sclerosis receiving disease modifying therapies: disproportionality analysis using the EudraVigilance database

BACKGROUND

Monoclonal antibodies targeting CD20, such as rituximab, ocrelizumab, and ofatumumab, are crucial in managing multiple sclerosis (MS). However, they can cause hypogammaglobulinemia, increasing the risk of infections and autoimmune disorders.

RESEARCH DESIGN AND METHODS

This study describes cases of hypogammaglobulinemia in MS patients receiving anti-CD20 monoclonal antibodies, using data from the European spontaneous reporting system database, EudraVigilance.

RESULTS

A total of 135 individual case safety reports (ICSRs), covering 469 adverse drug reactions (ADRs), were retrieved. The majority of ICSRs were related to ocrelizumab (N = 93) and involved cases of hypogammaglobulinemia occurring in adult females. Almost 20% of ICSRs reported concomitant medications, mainly represented by antibiotics, vitamins and antiepileptics. Among the 469 ADRs, 36.8% were serious, and 66% had an unknown outcome. The most commonly reported ADRs belonged to the SOC 'Infections and infestations' and included cases of COVID-19 and respiratory tract infection. Lastly, disproportionality analysis did not show a statistically significant probability of gamma globulin reduction comparing each drug.

CONCLUSIONS

The study highlights the importance of monitoring for the occurrence of hypogammaglobulinemia and infections in patients receiving ocrelizumab, ofatumumab and rituximab for MS. These ADRs can be extremely serious and highlight the need for ongoing research to optimize their safety profiles.

Impact of High-Efficacy Therapies for Multiple Sclerosis on B Cells

Multiple sclerosis (MS) is a chronic inflammatory and neurodegenerative autoimmune disorder of the central nervous system characterized by demyelination and neurodegeneration. Traditionally considered a T-cell-mediated disease, the crucial role of B lymphocytes in its pathogenesis, through different mechanisms contributing to inflammation and autoreactivity, is increasingly recognized. The risk of long-term disability in MS patients can be reduced by an early treatment initiation, in particular with high-efficacy therapies. The aim of this review is to provide an overview of the mechanisms of action of high-efficacy therapies for MS, with a focus on their impact on B cells and how this contributes to the drugs' efficacy and safety profiles. Anti-CD20 monoclonal antibodies, Alemtuzumab, Cladribine and sequestering therapies encompassing Natalizumab and S1P receptors modulators will be discussed and emerging therapies, including Bruton's Tyrosine Kinase inhibitors, will be presented.

Switching to ublituximab from prior anti-CD20 monoclonal antibody therapy: a case report series

Introduction

Anti-CD20 monoclonal antibody (mAb) therapies used to treat multiple sclerosis (MS) differ in their molecular structures, epitope recognition, and mechanisms of CD20-positive (CD20+) cell lysis, which may impact clinical efficacy and tolerability and support within-class switching for patients with suboptimal response to a prior anti-CD20 mAb.

Patients and methods

This is a retrospective case series of 7 individuals with MS treated in private practice or at an MS clinic who switched to ublituximab from a different anti-CD20 mAb therapy due to efficacy or tolerability concerns.

Case descriptions

Details of each case, including clinical and/or radiological outcomes on initial anti-CD20 mAb therapy, reasons for switching, and outcomes after starting ublituximab therapy are provided.

Discussion

These cases highlight suboptimal B-cell depletion, inadequate MS disease control, and/or tolerability concerns in people with MS who had clinical improvements or stabilization of disease following a switch from ocrelizumab or rituximab to ublituximab.

Conclusion

Within-class switching from a prior anti-CD20 mAb therapy to ublituximab is feasible and may improve outcomes in some people with MS.

Emerging Mechanisms and Biomarkers Associated with T-Cells and B-Cells in Autoimmune Disorders

Autoimmune diseases are characterized by the dysregulation of B-cells, which are responsible for antibody production against pathogens, and T-cells, which play a crucial role in cell-mediated immunity, including both helper and cytotoxic T-cells. These disorders frequently present with abnormal responses from both B- and T-cells, which can have a significant impact on cardiovascular health, particularly among the female patients. Key mechanisms contributing to these diseases include the activation of the NLRP3 inflammasome impaired efferocytosis is the process by which phagocytes clear apoptotic cells to maintain immune and developmental balance. Defects in this process can lead to inflammatory and autoimmune disorders. The gut microbiota helps defend against pathogens and signals immune cells, playing a vital role in human health and is involved in many aspects of the body. Novel therapeutic strategies such as nanomedicine and targeted treatments are being developed to restore immune balance. The significance of thymic homeostasis the influence of viral infections and the presence of tertiary lymphoid structures highlight the need for multidisciplinary approaches in the management of these conditions. A case study of a 9-year-old girl diagnosed with seronegative autoimmune encephalitis, who displayed severe obsessive-compulsive disorder (OCD) and aggressive behavior, exemplifies the complexities involved in treatment. Promising interventions, including CAR-T-cell therapy and nanomedicine, are under development for various autoimmune diseases, such as vitiligo and refractory autoimmune rheumatic diseases (ARDs). Furthermore, emerging therapies, including CAR-T-cell therapy, mRNA-based strategies, and microbiome modulation, are being explored alongside advancements in personalized medicine and early diagnostic techniques to improve patient outcomes for individuals affected by autoimmune diseases.

Real-world pharmacovigilance of ofatumumab in multiple sclerosis: a comprehensive FAERS data analysis

Background

Ofatumumab, a fully human monoclonal antibody targeting CD20, is approved for the treatment of relapsing multiple sclerosis. Comprehensive real-world safety data are crucial for informing clinical practice.

Methods

The FDA Adverse Event Reporting System database was utilized to perform a disproportionality analysis, covering reports from Q3 2020 to Q2 2024, in which ofatumumab was identified as the primary suspected drug. Statistical approaches used included the Reporting Odds Ratio, Proportional Reporting Ratio, Bayesian Confidence Propagation Neural Network, and Multi-item Gamma Poisson Shrinker. The timing of adverse events was assessed using the Weibull distribution model to highlight temporal risk patterns.

Results

Known adverse reactions, such as injection site reactions and upper respiratory tract infections, displayed positive signals. Additionally, novel off-label adverse events, including brain fog, muscle spasms, and mood alterations, were identified, marking the first real-world evidence of these potential risks. Temporal analysis revealed that most adverse events occurred within the first month of treatment, indicating an early risk phase. Subgroup analysis demonstrated notable differences in adverse event profiles by gender and age, with males more prone to hyperhidrosis and older patients more susceptible to neurological symptoms.

Conclusion

This real-world analysis of ofatumumab provides important safety insights, confirming known adverse reactions and identifying additional potential risks. Early and tailored monitoring protocols during the initial treatment phase, including regular neurological and psychiatric assessments, are recommended to optimize patient safety and outcomes. Prospective studies are recommended to validate these results and explore the underlying mechanisms.

Clinical and analytical monitoring of patients with multiple sclerosis on anti-CD20 therapeutics: a real-world safety profile study

Background

Anti-CD20 monoclonal antibodies are a class of immunosuppressive drugs widely used in the treatment of central nervous system (CNS) inflammatory diseases, with well-established efficacy and safety. Although rare, these therapies can be associated with serious adverse events including hematological and infectious complications. This study aims to evaluate their safety and tolerability profile in real-world clinical practice.

Methods

We conducted a retrospective cohort study comprising patients diagnosed with multiple sclerosis (MS) treated with anti-CD20 drugs since 2016 followed in the Demyelinating Diseases clinic of a tertiary center. Clinical and paraclinical parameters were evaluated, including complete blood count and immunoglobulins measurements.

Results

A total of 160 with multiple sclerosis (pwMS) were included in our study, of whom 110 (68.8%) were female and 147 are currently receiving anti-CD20 therapies. Half of the patients were diagnosed with relapsing-remitting MS, while the remaining had progressive forms, including 23 with primary-progressive MS and 57 with secondary-progressive MS. Eighty-three patients were on ocrelizumab, 48 on rituximab, and 29 on ofatumumab. The mean follow-up duration from the start of anti-CD20 therapy was 30.5 ± 21.3 months. During this period, serious adverse events were observed in 9 patients, including SARS-CoV-2 infection (resulting in one death), urinary tract infection, febrile neutropenia, severe diarrhea, and acute hepatitis. The rate of serious infections in the ocrelizumab subgroup was consistent with the literature, although a higher rate was observed in the rituximab subgroup. A positive correlation was found between serious infectious complications and lower IgG levels. Additionally, longer exposure to anti-CD20 therapy in our cohort was associated with an increased risk of IgG deficiency and a higher incidence of serious infections. Lymphopenia was detected in 25 patients, though it was not directly linked to the occurrence of serious infections.

Conclusion

Our work confirms the tolerability and safety of anti-CD20 drugs in a real-world clinical practice MS cohort, despite their frequent association with analytical changes such as lymphopenia and hypogammaglobulinemia. To better understand the clinical significance of hypogammaglobulinemia secondary to anti-CD20 treatment and to develop strategies for mitigating the associated potential infection risk, future studies with larger populations are essential.

Profile of Ofatumumab in the Treatment of Multiple Sclerosis: Design, Development and Place in Therapy

Targeting B cells through monoclonal antibodies against CD20 has emerged as a highly effective strategy in managing disease activity in patients with relapsing forms of multiple sclerosis. This efficacy was initially demonstrated with rituximab and further affirmed with ocrelizumab. Ofatumumab is the first fully human IgG1 monoclonal antibody (mAb) approved for the treatment of MS. It is characterized by its convenient self-administered regimen of once-monthly subcutaneous injections. Its human antibody nature contributes to a significantly lower risk of immunogenicity compared to rituximab. Clinical trials have consistently shown its effectiveness in significantly reducing annualized relapse rates, MRI-detected lesion activity, and disability progression when compared to teriflunomide, a standard therapy for MS. Additionally, ofatumumab exhibits a manageable tolerability profile, with adverse events primarily comprising infections and injection-related reactions. This review describes ofatumumab pharmacology, core clinical trial data and clinical efficacy in addition to safety issues.

Novel approaches to primary membranous nephropathy: Beyond the KDIGO guidelines

Primary membranous nephropathy (PMN) is an immune-mediated glomerular disease. Rituximab (RTX) is recommended as a first-line immunosuppressive therapy and shows high clinical efficacy, but the optimal doses remain controversial. Approximately 20%-40% of PMN patients experience RTX resistance and failure. Reduced bioavailability, RTX internalization and attack, anti-RTX antibody production, autoreactive B-cell reservoirs and chronic and irreversible renal damage may contribute to this problem. Therefore, new treatment modalities are needed to compensate for this deficit. New interventions and new dose combinations are being proposed. Multiple drug combination therapies show comparable clinical efficacy to conventional treatments by blocking the production of disease-causing antibodies in multiple directions, and can reduce single-agent doses without increasing adverse effects. New therapies that directly target B cells, plasma cells, and antibody production have shown encouraging results. In addition, new techniques for sweeping antibodies and chimeric antigen receptor T-cell therapy also may be promising strategies for PMN. Immunoadsorption could be used as an auxiliary choice for severe cases. This article explores new treatments for PMN and highlights possible mechanisms for potential new technologies that offer new ideas for treatment.

Quality of life and tolerability of B-cell directed therapy of multiple sclerosis with ofatumumab in a patient-centered real-world observational study

INTRODUCTION

Ofatumumab (Kesimpta®) is a subcutaneous CD20-targeting antibody approved in Germany in 2021 for the treatment of relapsing multiple sclerosis (RMS). After careful instruction, patients can administer the treatment themselves. We previously reported data of 101 patients (Klimas et al. in Nervenarzt 94:923-933, 2023). The objective of this longitudinal study is to explore the tolerability and acceptability of ofatumumab from a patient perspective over a follow up period of 6 months.

METHODS

In this prospective observational real-world study, we report follow up data of 81 patients. We evaluated sociodemographic data, disease duration, duration and side effects of ofatumumab use, expanded disability status scale (EDSS), Beck Depression Inventory II (BDI-II), Short-Form 36 (SF-36), Fatigue Scale of Motor and Cognitive Functions (FSMC), and modified Multiple Sclerosis Functional Composite Test (MSFC). In addition, we asked for subjective treatment outcomes, such as impact on quality of life, walking distance, concentration, mood, medication adherence, fatigue and the subjective course of MS on a numerical rating scale (1 = very negative; 5 = very positive). Furthermore, treatment discontinuations were recorded.

RESULTS

The average duration of ofatumumab treatment was 10 months. In comparison to previous published data of our cohort, patients reported a significant increase in headache (10% up to 26%, p = 0.004) and limb pain (5% up to 26%, p < 0.001) as persistent side effects after the injections. More patients reported a very positive effect (p < 0.0001) on quality of life. 4 confirmed relapses occurred but no EDSS worsening, and no treatment discontinuations were documented during the observation period.

DISCUSSION

As previously described, our prospective study indicates that patients have a good tolerability of ofatumumab, precisely because of the mild and few side effects at the first administration. However, the longer the observation period, the more headaches and limb pain occurred after the injections. Despite this, patients' subjective quality of life improved. There were no discontinuations during the follow-up period, with the limitation of a high loss to follow-up.

Current Knowledge about CD3+CD20+ T Cells in Patients with Multiple Sclerosis

Multiple sclerosis (MS) is a disease of the central nervous system (CNS) characterized by inflammation and autoimmune responses. This review explores the participation of T cells, particularly certain CD3+CD20+ T cells, in the clinical manifestations of MS and highlights their presence in diagnosed patients. These T cells show aberrant expression of CD20, normally considered a B-cell marker. In this review, relevant journal articles available in PubMed and CINAHL were identified by employing diverse search terms, such as MS, CD3+CD20+ T cells, the incidence and significance of CD3+CD20+ T cells in MS patients, and the impact of rituximab treatment. The search was limited to articles published in the ten-year period from 2014 to 2024. The results of this review suggest that most scholars agree on the presence of CD3+CD20+ T cells in cerebrospinal fluid. Emerging concepts relate to the fundamental role of CD20-expressing T cells in determining the target and efficacy of MS therapeutics and the presence of T cells in the cerebrospinal fluid of MS patients. The results clearly show that CD20+ T cells indicate disease chronicity and high disease activity.

Dental Adverse Effects of Anti-CD20 Therapies

INTRODUCTION

Over the past few years, anti-CD20 therapies like rituximab, ocrelizumab or ofatumumab have seen an increase in interest in the treatment of neurological autoimmune disorders such as multiple sclerosis (MS), neuromyelitis optica spectrum disorders (NMOSD), or resistant forms of generalized myasthenia gravis (MG). They are generally well-tolerated, but recent reports have highlighted severe dental disorders in patients undergoing anti-CD20 therapies. The aim was to describe a series of cases and to compare with the available scientific literature.

METHODS

We reviewed 6 patient cases with dental disorders during anti-CD20 therapy that were reported to the pharmacovigilance center. A disproportionality analysis was also conducted on Vigibase® for each anti-CD20 and each adverse effect described in the cases.

RESULTS

Six cases of dental and gingival conditions in relatively young patients were reported (median age: 40.5 years old [min: 34; max: 79]). Oral conditions were developed in four patients with MS treated with ocrelizumab and in two patients receiving rituximab (one patient with MG and one with NMOSD). The onset of oral conditions ranged from 10 days to 2 years after treatment initiation. Notably, all patients treated with ocrelizumab experienced gingival recession. Various dental pathologies were observed, including tooth loss, dental pain, caries, brittle teeth, dental fractures, dental abscesses, and periodontitis. Analysis of Vigibase® revealed 284 worldwide cases of dental and gingival conditions under ocrelizumab, 386 cases under rituximab, and 80 under ofatumumab. Significant associations were found between these therapies and dental pathologies, particularly tooth abscesses and infections.

CONCLUSION

To our knowledge, this is the first case series reporting dental conditions developed in patients long-term treated with anti-CD20 treatments. This issue, literature data, and Vigilyze® analysis might be considered a safety signal that necessitates being confirmed with more robust data, such as a retrospective study with a control group. Meanwhile, proactive measures are essential like frequent dental checkups and dental hygienic measures to prevent oral health problems associated with anti-CD20 therapies.

Effectiveness of tixagevimab/cilgavimab (Evusheld) in antiCD20‑treated patients with multiple sclerosis and neuromyelitis optica spectrum disorder

BACKGROUND

AntiCD20 therapy, such as rituximab, ocrelizumab, or ofatumumab, effectively treats patients with multiple sclerosis (pwMS) or neuromyelitis optica spectrum disorder (pwNMOSD) but negatively affects the humoral immune response to COVID-19 vaccination. One strategy to protect these patients is using tixagevimab/cilgavimab (T/C) as pre-exposure prophylaxis. This study aimed to evaluate the effect of T/C on the incidence of COVID-19 in pwMS and pwNMOSD.

METHODS

Data in this observational cohort study were collected in two Czech MS centres through ReMuS registry between March 1, 2020 and December 31, 2022. Adult pwMS and pwNMOSD who were (1) treated with antiCD20 therapy at least six months before T/C administration, or at least from February 1, 2022 in the control group; (2) were already on antiCD20 therapy at the time of vaccination or COVID-19 infection; and (3) were on antiCD20 therapy at least 100 days after T/C, or at least 90 days after August 1, 2022 in the control group, were included. Analysis was performed using frequency-based (propensity score matching) and Bayesian statistical methods (informative and non-informative priors).

RESULTS

Using propensity score matching 1:1, 47 patients who received T/C (mean age 45.7 years, median disease duration 12.5 years) were matched with those who did not receive T/C (n = 341; mean age 46.6 years, median disease duration 11.4 years) based on age, MS/NMOSD duration, and number of vaccine doses. None of the T/C patients and three in the control matched group, developed COVID-19 between 10 and 100 days after receiving T/C, August 1, 2022, respectively. The frequency of COVID-19 was not significantly different between groups (p = 0.242). Due to the low number of patients, a Bayesian analysis was also added. Using a non-informative Bayesian prior, the median relative risk of COVID-19 after T/C was 7.6 % (95 % CrI 0.02-115.9 %). The posterior probability of risk difference lower than zero was 96.4 %. Using an informative prior (based on the registration study of Evusheld), the median relative risk of COVID-19 after T/C was 20.2 % (95 % CI 8.4-43.8 %). The posterior probability of the risk difference lower than zero was 100 %.

CONCLUSION

This work highlights the possible good efficacy of T/C in antiCD20-treated pwMS and pwNMSOD. Based on Bayesian analysis with an informative prior, the T/C group's risk of COVID-19 infection was approximately 20.2 % of the control group's risk. However, given the low frequency of COVID-19, the results of this pilot analysis must be interpreted with caution.