Late onset absolute neutropenia associated with ocrelizumab treatment in multiple sclerosis: A case report and review of the literature

Recurrent late-onset neutropenia following treatment with different B cell-depleting strategies in multiple sclerosis

BACKGROUND

As B cell-depleting therapies in multiple sclerosis (MS) have gained significant importance in the last several years, their long-term safety profile is of considerable clinical interest. Late-onset neutropenia (LON) is a rare, but potentially severe, adverse event that was first described in patients with rheumatic disorders under therapy with rituximab. Ofatumumab was approved in 2021 for the treatment of relapsing-remitting multiple sclerosis (RRMS). Neutropenia occurred in 0.2% of patients in clinical phase 3 trials, and to date, no cases of LON have been reported under ofatumumab treatment.

METHODS

Here, we report a case of repetitive symptomatic LON under ocrelizumab as well as ofatumumab treatment. Additionally, we review the literature on rare occurrences of LON in patients with MS, neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) undergoing B cell-depleting therapies, including rituximab, ocrelizumab, ofatumumab, inebilizumab, and ublituximab.

FINDINGS

In our case, the patient presented with repetitive symptomatic LON under ocrelizumab as well as ofatumumab treatment leading to febrile infections, subsequent use of antibiotics, and application of granulocyte-colony-stimulating factor. After repetitive episodes of LON under both B cell-depleting strategies, cladribine was subsequently initiated. A nine-month follow-up showed a normal neutrophil count and no evidence of disease activity.

CONCLUSIONS

This case highlights the significance of symptomatic late-onset blood count changes under both ocrelizumab and ofatumumab and emphasizes the importance of continuous monitoring of the differential blood count under B cell-depleting treatment.

FUNDING

This study was supported by the Deutsche Forschungsgemeinschaft (DFG; SFB CRC-TR-128 to F.Z., V.F., and S.B..; SFB 1080 and SFB CRC-1292 to F.Z..; and SFB/TRR 355 to S.B.) and the Hermann and Lilly Schilling Foundation (to S.B.).

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.

Severe Late-Onset Neutropenia in a Pregnant Patient with Multiple Sclerosis after Ocrelizumab

Introduction

Ocrelizumab is a recombinant humanized anti-CD20 monoclonal antibody used to treat multiple sclerosis. Late-onset neutropenia, absolute neutrophil count <1.5 × 109/L that develops >4 weeks after last drug administration, is a known adverse event associated with anti-CD20 monoclonal antibodies, including rituximab and ocrelizumab.

Case Presentation

We present the case of a 27-year-old woman who developed severe late-onset neutropenia during her third trimester of pregnancy after treatment with ocrelizumab 6 months prior.

Conclusion

Neurologists should be aware of this risk and consider additional hematologic monitoring for pregnant patients who received anti-CD20 therapy as therapies such as G-CSF are available to help prevent serious infections.

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.

Disease-modifying therapies and hematological disorders: a systematic review of case reports and case series

Introduction

Disease modifying therapies (DMTs) used to treat multiple sclerosis (MS) can be associated to the occurrence of hematological disorders. This systematic review aims to provide an overview of these events occurring in real-life conditions, by describing case reports and series published in the literature.

Methods

A literature search of all publications up to January 5th 2024 on the Medline and Embase databases was carried out. The results were presented both in the text and in tables.

Results

Sixty-seven case reports/series were included in this review, of which more than half related to alemtuzumab, natalizumab and ocrelizumab. The publication date of included studies ranged from 2006 to 2024. The majority of case reports and series described the occurrence of late-onset hematological disorders (events that occurred more than 30 days after the first DMT administration), mainly represented by case of neutropenia, autoimmune hemolytic anemia and immune thrombocytopenia. All cases reported a favorable outcome, apart one case report that described a fatal case. Among included cases, 4 articles, all related to natalizumab, described the occurrence of myeloid disorders in 13 newborns from mother receiving the DMT.

Discussion

Considering the limitations identified in the majority of included studies, further ad hoc studies are strongly needed to better evaluate the hematological disorders of DMTs. Meantime, the strict monitoring of treated patients for the occurrence of these toxicities should be highly recommended.

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.

A Case of Late-Onset Neutropenia in Relapsing-Remitting Multiple Sclerosis Following Ocrelizumab Therapy

Ocrelizumab, a monoclonal antibody, has proven effective in treating both primary progressive and relapsing-remitting multiple sclerosis. Common adverse effects observed in clinical studies include flushing, sore throat, pruritus, and rash. This abstract discusses a case of severe, late-onset neutropenia in a patient with relapsing-remitting multiple sclerosis undergoing ocrelizumab treatment. The neutropenia emerged 46 days following the patient's most recent ocrelizumab dose. The patient responded well to treatment with intravenous meropenem and filgrastim. This rare and unforeseen adverse effect highlights the importance of regular blood monitoring for early detection of severe neutropenia in patients treated with ocrelizumab.

Recurrence of severe symptomatic late-onset neutropenia on ocrelizumab

BACKGROUND

Late-onset neutropenia (LON), defined as an absolute neutrophil count (ANC) < 1500/mm3 that develops between 4 weeks and 6 months after the last drug administration, is a rare side effect of anti-CD20 drugs including ocrelizumab. Although continuation of ocrelizumab after LON is not contraindicated, the risk of LON recurrence is not well known.

CASES

We report three cases of recurrent symptomatic agranulocytosis (ANC < 500/mm3) occurring under ocrelizumab.

CONCLUSION

Given the risk of recurrence of symptomatic agranulocytosis and the availability of other treatments, a therapeutic switch may be discussed after the first episode of LON.

Anti-CD20 therapies in multiple sclerosis: From pathology to the clinic

The immune system plays a significant role in multiple sclerosis. While MS was historically thought to be T cell-mediated, multiple pieces of evidence now support the view that B cells are essential players in multiple sclerosis pathogenic processes. High-efficacy disease-modifying therapies that target the immune system have emerged over the past two decades. Anti-CD20 monoclonal antibodies selectively deplete CD20+ B and CD20+ T cells and efficiently suppress inflammatory disease activity. These monotherapies prevent relapses, reduce new or active magnetic resonance imaging brain lesions, and lessen disability progression in patients with relapsing multiple sclerosis. Rituximab, ocrelizumab, and ofatumumab are currently used in clinical practice, while phase III clinical trials for ublituximab have been recently completed. In this review, we compare the four anti-CD20 antibodies in terms of their mechanisms of action, routes of administration, immunological targets, and pharmacokinetic properties. A deeper understanding of the individual properties of these molecules in relation to their efficacy and safety profiles is critical for their use in clinical practice.

Acquired B-cell deficiency secondary to B-cell-depleting therapies

The advantage of the newer biological therapies is that the immunosuppressive effect is targeted, in contrast, to the standard, traditional immunomodulatory agents, which have a more global effect. However, there are unintended targets and consequences, even to these "precise" therapeutics, leading to acquired or secondary immunodeficiencies. Besides depleting specific cellular immune subsets, these biological agents, which include monoclonal antibodies against biologically relevant molecules, often have broader functional immune consequences, which become apparent over time. This review focuses on acquired B-cell immunodeficiency, secondary to the use of B-cell depleting therapeutic agents. Among the many adverse consequences of B-cell depletion is the risk of hypogammaglobulinemia, failure of B-cell recovery, impaired B-cell differentiation, and risk of infections. Factors, which modulate the outcomes of B-cell depleting therapies, include the intrinsic nature of the underlying disease, the concomitant use of other immunomodulatory agents, and the clinical status of the patient and other co-existing morbidities. This article seeks to explore the mechanism of action of B-cell depleting agents, the clinical utility and adverse effects of these therapies, and the relevance of systematic and serial laboratory immune monitoring in identifying patients at risk for developing immunological complications, and who may benefit from early intervention to mitigate the secondary consequences. Though these biological drugs are gaining widespread use, a harmonized approach to immune evaluation pre-and post-treatment has not yet gained traction across multiple clinical specialties, because of which, the true prevalence of these adverse events cannot be determined in the treated population, and a systematic and evidence-based dosing schedule cannot be developed. The aim of this review is to bring these issues into focus, and initiate a multi-specialty, data-driven approach to immune monitoring.

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.

Ocrelizumab associated late-onset neutropenia in the patient with multiple sclerosis: Case report and literature review

Introduction. Ocrelizumab is a recombinant humanized monoclonal antibody that selectively depletes CD20-expressing B cells, which is approved for the treatment of the relapsing and primary progressive multiple sclerosis (MS). It is extremely rarely associated with late onset neutropenia (LON), as an adverse event. Case Outline. We describe a case, from the Treatment Registry of the Clinic of Neurology, University Clinical Center of Serbia, Belgrade, of a transient, asymptomatic, LON which was detected in a na?ve relapsing-remitting MS patient, six-months after treatment with ocrelizumab. Conclusion. Having in mind all until now available data, which indicate that rarely occurring LON on ocrelizumab is asymptomatic and transient in the majority of cases, we assume that it may be suggested that only in patients with complaints suggesting the presence of possible infection, additional complete blood count monitoring, should be mandatory, exclusively at that moment, apart from the precisely defined regular follow-up.

Severe late-onset neutropenia induced by ocrelizumab in a multiple sclerosis patient: A case report

Ocrelizumab is a recombinant humanized antibody targeted against CD-20 molecule, which was approved for the treatment of relapsing and primary progressive multiple sclerosis. Common adverse events of ocrelizumab include infusion-related reactions like rash, pruritus, and flushing. Late-onset neutropenia (LON) is a rarely reported complication of ocrelizumab therapy. We report a case of severe late-onset neutropenia in a patient with primary progressive multiple sclerosis treated with ocrelizumab with neutropenia occurring 3 months after the last dose received treated with empirical broad-spectrum intravenous antibiotics and filgrastim. Severe late-onset neutropenia is a rare unpredictable adverse event and outlines the importance of regular routine blood workup for detecting severe neutropenia early in its course.

Product review on MAbs (alemtuzumab and ocrelizumab) for the treatment of multiple sclerosis

Traditionally, the management of active relapsing remitting MS was based on the, so-called, maintenance therapy, which is characterized by continuous treatment with particular disease modifying therapy (DMT), and a return of disease activity when the drug is discontinued. Another approach is characterized by a short treatment course of a DMT, which is hypothesized to act as an immune reconstitution therapy (IRT), with the potential to protect against relapses for years after a short course of treatment. Introduction of monoclonal antibodies in the treatment of MS has revolutionized MS treatment in the last decade. However, given the increasingly complex landscape of DMTs approved for MS, people with MS and neurologists are constantly faced with the question which DMT is the most appropriate for the given patient, a question we still do not have an answer to. In this product review, we will discuss the first DMT that acts as IRT, an anti-CD52 monoclonal antibody alemtuzumab and an anti CD20 monoclonal antibody, ocrelizumab that has the potential to act as an IRT, but is administered continuously. Special emphasis will be given on safety in the context of COVID-19 pandemics and vaccination strategies.

Late-onset neutropenia after anti-CD20 therapy for multiple sclerosis, neuromyelitis optica spectrum disorders and MOG antibody-associated disease: A prospective study

Late-onset neutropenia (LON) after anti-CD20 therapy is a poorly described side effect in inflammatory disorders of the CNS. In this prospective study, patients treated with Rituximab or Ocrelizumab for MS, neuromyelitis optica spectrum disorders or MOG antibody-associated disease (MOGAD) were asked to perform complete blood count (CBC) every two weeks for six months, with the aim of identifying LON. Out of 152 patients, two (1,32%) had an absolute neutrophil count <1,000/mm³: one patient with MOGAD had agranulocytosis and one patient with MS had grade 3 neutropenia. Both were asymptomatic. These results confirm that LON after anti-CD20 therapy in inflammatory disorders of the CNS is not exceptional. Nevertheless, this biological complication remains too infrequent to justify close systematic CBC follow-up.

Targeting B cells in multiple sclerosis

PURPOSE OF REVIEW

Treatments targeting B cells are increasingly used for patients with multiple sclerosis (MS). We review the mechanisms of action, clinical effectiveness and safety of treatment, with emphasis on recently published studies.

RECENT FINDINGS

Several monoclonal antibodies targeting the surface molecule CD20 on B cells are approved or being developed for treatment of MS. Overall, they seem comparable in terms of strongly suppressing radiological disease activity and relapse biology. Novel approaches include anti-CD19 antibody therapy and treatment with oral drugs targeting Bruton's tyrosine kinase (BTK). The main safety issue with persistent B cell depletion is an increased risk of infections - possibly including an increased risk of severe COVID-19. Vaccine responses are also blunted in patients treated with anti-CD20 antibodies. Lower doses or longer infusion intervals may be sufficient for control of disease activity. Whether this might also improve the safety of treatment and increase vaccination responses remains to be determined.

SUMMARY

Available data support the widespread use of therapies targeting B cells in MS. Whether novel approaches targeting CD19 or BTK will have advantages compared to anti-CD20 antibody therapy remains to be established. Furthermore, trials investigating alternative dosing regimens for anti-CD20 antibody treatment are warranted.

Severe Delayed-Onset Neutropenia Induced by Ocrelizumab

Background

Ocrelizumab is an anti-CD20 monoclonal antibody that has been shown to reduce disability progression in primary progressive multiple sclerosis (MS). The adverse event profile is still being determined through postmarketing surveillance and case reports.

Objective

To report a case of severe late-onset neutropenia associated with ocrelizumab in a patient with primary progressive MS.

Methods

Case report.

Result

A 34-year-old male with primary progressive MS developed severe late-onset neutropenia 42 days after infusion of ocrelizumab, which necessitated hospital admission and administration of broad-spectrum antibiotics and granulocyte colony-stimulating factor.

Conclusion

Late-onset neutropenia is a rare complication of ocrelizumab. Patients should be counseled to present for urgent evaluation if they develop fever.

Predicting Infection Risk in Multiple Sclerosis Patients Treated with Ocrelizumab: A Retrospective Cohort Study

BACKGROUND

Ocrelizumab safety outcomes have been well evaluated in clinical trials and open-label extension (OLE) studies. However, risk factors for infection in patients with multiple sclerosis (MS) receiving ocrelizumab have not been extensively studied in the real-world setting.

OBJECTIVE

The aim of this study was to examine factors determining risk of self-reported infections and antimicrobial use in patients receiving ocrelizumab for MS.

METHODS

A retrospective, observational cohort study was conducted in patients receiving ocrelizumab at the Royal Melbourne Hospital. Infection type and number were reported by patients, and the associations of potential clinical and laboratory risk factors with self-reported infection and antimicrobial use were estimated using univariate and multivariable logistic regression models.

RESULTS

A total of 185 patients were included in the study; a total of 176 infections were reported in 89 patients (46.1%), and antimicrobial use was identified in 47 patients (25.3%). In univariate analyses, a higher serum IgA was associated with reduced odds of infection (OR 0.44, 95% CI 0.25-0.76). In multivariable analyses, older age (OR 0.94, 95% CI 0.88-0.99), higher serum IgA (OR 0.37, 95% CI 0.17-0.80) and higher serum IgG (OR 0.81, 95% CI 0.67-0.99) were associated with reduced odds of infection. Older age (OR 0.85, 95% CI 0.75-0.96) and higher serum IgA (OR 0.23, 95% CI 0.07-0.79) were associated with reduced odds of antimicrobial use, whilst longer MS disease duration (OR 1.22, 95% CI 1.06-1.41) and higher Expanded Disability Status Scale (EDSS) score (OR 1.99, 95% CI 1.02-3.86) were associated with increased odds of antimicrobial use.

CONCLUSIONS

Higher serum IgA and IgG and older age were associated with reduced odds of infection. Our findings highlight that infection risk is not uniform in patients with MS receiving ocrelizumab and substantiate the need to monitor immunoglobulin levels pre-treatment and whilst on therapy.

Safety of Newer Disease Modifying Therapies in Multiple Sclerosis

In the past decade, the therapeutic arsenal for multiple sclerosis has expanded greatly. Newer more potent disease modifying therapies (DMTs) with varying mechanisms of actions are increasingly used early in the disease course. These newer DMTs include oral therapies (teriflunomide, dimethyl fumarate, fingolimod, siponimod, ozanimod, and cladribine) and infusion therapies (natalizumab, alemtuzumab, and ocrelizumab), and are associated with better control of disease activity and long-term outcomes in patients with MS compared to older injectable therapies (interferon beta and glatiramer acetate). However, they are associated with safety concerns and subsequent monitoring requirements. Adverse events are initially observed in phase 2 and 3 clinical trials, and further long-term data are collected in phase 3 extension studies, case series, and post-marketing reports, which highlight the need to periodically re-evaluate and adjust monitoring strategies to optimize treatment safety in an individualized approach.

Safety profile of ocrelizumab for the treatment of multiple sclerosis: a systematic review

INTRODUCTION

We systematically reviewed adverse events (AEs) for ocrelizumab for multiple sclerosis (MS).

AREAS COVERED

We searched Medline, Embase, Web of Science, and Toxicology Data Network-TOXLINE (inception to 8-July-2020), clinical trial registries, and product monographs for any clinical trials, observational studies or case reports examining AEs to ocrelizumab. Studies with/without a comparator drug or placebo were eligible.

EXPERT OPINION

Seventy-eight records were included (4 randomized controlled trials (RCTs), 4 open-label trials, 29 observational studies, and 27 case reports). AEs affected 2756/4498 (61.3%) of ocrelizumab-exposed patients. The most common AEs were infections (n=1342, 39.2% of ocrelizumab-exposed patients) and infusion-related reactions (n=1391, 26.2%). Compared to beta-interferon, infections were more likely in ocrelizumab-exposed patients (Risk Ratio (RR)=1.10; 95% confidence interval (CI):1.01-1.19), including: herpes-related (RR=1.75; 95%CI:1.11-2.76), respiratory tract-related (RR=1.42; 95%CI:1.10-1.84 and RR=1.61; 95%CI:1.10-2.35), nasopharyngitis (RR=1.47; 95%CI:1.13-1.90), and rhinitis (RR=4.00; 95%CI:1.13-14.14). Infusion-related reactions (RR range: 1.57-4.42) were more common for ocrelizumab versus placebo or beta-interferon. From pooled analyses (three RCTs), the risk of 'any' serious AE did not differ significantly between the ocrelizumab and comparator groups. However, insufficient data were available to assess longer-term AEs, e.g., malignancy.

Adverse event profile differences between rituximab and ocrelizumab: Findings from the FDA Adverse Event Reporting Database

BACKGROUND

Rituximab and ocrelizumab are anti-CD20 monoclonal antibodies that have shown a marked reduction in multiple sclerosis (MS) inflammatory activity. However, their real-world safety profile has not been adequately compared.

OBJECTIVE

To investigate the adverse event (AE) profile of rituximab and ocrelizumab reported to the Food and Drug Administration Adverse Event Reporting System (FAERS) database.

METHODS

The FAERS database was filtered by indication (MS) and drug (rituximab or ocrelizumab). Disproportionality analyses including but not limited to reporting odds ratio (ROR) were conducted to identify drug-AE associations. A signal was detected if the lower limit of the 95% confidence interval of ROR (ROR₀₂₅) exceeded 1.

RESULTS

There were 623 and 7948 reports for rituximab and ocrelizumab, respectively. The most frequent AEs with rituximab and ocrelizumab were infusion-related reaction (4.82%) and urinary tract infection (10.52%), respectively. The strongest drug-AE association for rituximab and ocrelizumab were ear pruritus (ROR₀₂₅: 47.53) and oral herpes (ROR₀₂₅: 38.99), respectively. Ocrelizumab was associated with an almost two times higher frequency of infections than rituximab (21.93% vs 11.05%, respectively).

CONCLUSION

This study revealed differences in reporting AEs between rituximab and ocrelizumab. Infections were reported more frequently with ocrelizumab. Although speculative, a potentially different or more extensive B-cell depletion by ocrelizumab might explain these findings. Additional pharmacovigilance studies need to be performed to better characterize differences in the AE profile in B-cell-depleting therapies.

[Ocrelizumab for treatment of multiple sclerosis]

Ocrelizumab ist ein monoklonaler Antikörper, der sich gegen das Differenzierungsantigen CD20 richtet und zu einer effektiven längerfristigen Depletion von Lymphozyten, insbesondere von B‑Zellen, führt. Unlängst publizierte Phase-3-Studien belegen, dass Ocrelizumab sowohl bei der Behandlung der schubförmigen als auch der primär progressiven Multiplen Sklerose (MS) wirksam ist. Darauf basierend wurde Ocrelizumab als erstes Medikament zur Behandlung der primär chronisch-progredienten MS zugelassen. Um diesen Durchbruch besser in den Kontext des heutigen MS-Therapiekanons einordnen zu können, lohnt sowohl ein Blick zurück auf die Entwicklung der antikörpervermittelten CD20-Depletion als auch auf die der Zulassung zugrunde liegenden Studien sowie deren Extensionsphasen. Diese Übersichtsarbeit diskutiert die verfügbaren Daten zur Wirksamkeit und Sicherheit der langfristigen B‑Zell-Depletion bei MS-Patienten und erörtert den aktuellen Kenntnisstand zur Rolle von B‑Lymphozyten in der Immunpathogenese der MS.