Central nervous system lymphoma associated with natalizumab

A safety review of current monoclonal antibodies used to treat multiple sclerosis

INTRODUCTION

Multiple sclerosis (MS) is an autoimmune disease affecting the central nervous system. Monoclonal antibodies (mAbs) have shown efficacy in reducing MS relapse rates, disease progression, and brain lesion activity.

AREAS COVERED

This article reviews the literature on the use of mAbs for the treatment of MS, including their mechanisms of action, clinical trial data, safety profiles, and long-term outcomes. The review focuses on the three main categories of mAbs used in MS: alemtuzumab, natalizumab, and anti-CD20 drugs. A literature search was conducted using relevant keywords and guidelines and reports from regulatory agencies were reviewed. The search covered studies published from inception to 31 December 202231 December 2022. The article also discusses the potential risks and benefits of these therapies, including their effects on infection rates, malignancies, and vaccination efficacy.

EXPERT OPINION

Monoclonal antibodies have revolutionized the treatment of MS, but safety concerns must be considered, particularly with regards to infection rates, malignancy risk, and vaccination efficacy. Clinicians must weigh the potential benefits and risks of mAbs on an individual patient basis, taking into account factors such as age, disease severity, and comorbidities. Ongoing monitoring and surveillance are essential to ensure the long-term safety and effectiveness of monoclonal antibody therapies in MS.

Successful Management of Natalizumab-Associated Primary Central Nervous System Lymphoma through Autologous Stem Cell Transplant

Natalizumab is used as a second-line treatment for multiple sclerosis (MS). Some reports have linked natalizumab to primary central nervous system lymphoma (PCNSL), although few have described its management. A 45-year-old woman with Balo’s Concentric Sclerosis presented dizziness, vertigo accompanied by dysarthria, weakness on the left side and blurred vision to the right eye after the fourth dose of natalizumab. Magnetic resonance imaging (MRI) and a brain biopsy confirmed the diagnosis of PCNSL. The patient received modified PCNSL chemotherapy (MATRix protocol) followed by high-dose chemotherapy (HDC) supported by an autologous hematopoietic stem cell transplant (ASCT) as a consolidation therapy. Thirty months later, she is still in complete remission of her PCNSL and MS. In this case, whole brain radiotherapy was excluded because it may be associated with an increased risk of neurotoxicity in MS. ASCT was preferred because it has been shown to prevent disability progression in less advanced MS stages. Our patient is the second to receive an ASCT in this context and this option of treatment should be the preferred if the patient is eligible.

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.

Established and Emerging Immunological Complications of Biological Therapeutics in Multiple Sclerosis

Biologic immunotherapies have transformed the treatment landscape of multiple sclerosis. Such therapies include recombinant proteins (interferon beta), as well as monoclonal antibodies (natalizumab, alemtuzumab, daclizumab, rituximab and ocrelizumab). Monoclonal antibodies show particular efficacy in the treatment of the inflammatory phase of multiple sclerosis. However, the immunological perturbations caused by biologic therapies are associated with significant immunological adverse reactions. These include development of neutralising immunogenicity, secondary immunodeficiency and secondary autoimmunity. These complications can affect the balance of risks and benefits of biologic agents, and 2018 saw the withdrawal from the market of daclizumab, an anti-CD25 monoclonal antibody, due to concerns about the development of severe, unpredictable autoimmunity. Here we review established and emerging risks associated with multiple sclerosis biologic agents, with an emphasis on their immunological adverse effects. We also discuss the specific challenges that multiple sclerosis biologics pose to drug safety systems, and the potential for improvements in safety frameworks.

Natalizumab-Associated Primary Central Nervous System Lymphoma

OBJECTIVE

Natalizumab, a selective adhesion molecule inhibitor binding to an α-4 subunit of integrin, has emerged to be an effective immunomodulator, especially in the treatment of relapsing-remitting multiple sclerosis and Crohn disease. Recent reports documenting the development of primary central nervous system lymphoma (PCNSL) as a result of its administration have been concerning, and they trigger a debate about a possible causal association. In our report, we provide a comprehensive review of the literature on lymphoma development after natalizumab use, and we report an additional case of PCNSL development in a young woman who received natalizumab for her Crohn disease.

METHODS

A systematic (qualitative) review of literature on lymphoma development after natalizumab therapy was performed by use of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data on patient characteristics, indication for drug therapy, dosages, radiologic findings, potential risk factors for PCNSL, and tumor markers were synthesized. Additionally, we present the findings from the case of a young woman who received natalizumab therapy (4 doses, 300 mg each) for Crohn disease and in whom PCNSL developed.

RESULTS

Overall, 8 reports including our index case document lymphoma development after natalizumab use. Our case finding revisits the debate suggesting a remote possibility of association that warrants further evaluation and validation.

CONCLUSIONS

Evidence documenting a causal association of natalizumab and PCNSL is weak. Considering the potential benefits of using natalizumab for current indications, we recommend vigilant monitoring of patients receiving the drug for PCNSL outlook.

Long-term safety evaluation of natalizumab for the treatment of multiple sclerosis

INTRODUCTION

Natalizumab is a humanized monoclonal antibody highly effective in relapsing-remitting multiple sclerosis (MS). Important concerns about its safety have been pointed out mainly because of the risk of progressive multifocal leukoencephalopathy (PML), caused by the opportunistic John-Cunningham virus (JCV). Areas covered: This review analyzes all the safety aspects related to the use and safety of natalizumab in MS patients. Other than PML, post-marketing, safety red-flags have been reported, as liver or haematological serious adverse events. Pregnancy evidences will be pointed out. The risk of PML depends on: concomitant or previous immunosuppression, exposure duration, anti-JCV antibody level. In natalizumab-related PML the average survival is 77%; prognostic features and information for the earliest identification of PML have been identified to maximally reduce its incidence, mortality and morbidity. Expert opinion: Natalizumab is a highly effective drug for MS patients but its safety issues represent a relevant limitation and impose strict clinical surveillance of treated patients. Some post-marketing safety red-flags have been pointed out, with higher attention to severe liver failures and limphoma cases. If PML and its consequences are considered the most relevant issues, a continuous surveillance must be maintained also regarding other possible SAEs like liver diseases and malignancies.

Glioblastoma in natalizumab-treated multiple sclerosis patients

We present two natalizumab‐treated multiple sclerosis patients who developed glioblastoma multiforme (GBM) with variable outcomes. One patient had an isocitrate dehydrogenase (IDH)‐wildtype GBM with aggressive behavior, who declined treatment and died 13 weeks after symptoms onset. The other patient underwent resection of an IDH‐mutant secondary GBM that arose from a previously diagnosed grade II astrocytoma. He is still alive 5 years after the diagnosis of GBM. JC virus was not detected in either case. Whether natalizumab played a role in the development of GBM in those patients deserves further investigation.

Neuroimaging of Natalizumab Complications in Multiple Sclerosis: PML and Other Associated Entities

Natalizumab (Tysabri) is a monoclonal antibody (α4 integrin antagonist) approved for treatment of multiple sclerosis, both for patients who fail therapy with other disease modifying agents and for patients with aggressive disease. Natalizumab is highly effective, resulting in significant decreases in rates of both relapse and disability accumulation, as well as marked decrease in MRI evidence of disease activity. As such, utilization of natalizumab is increasing, and the presentation of its associated complications is increasing accordingly. This review focuses on the clinical and neuroimaging features of the major complications associated with natalizumab therapy, focusing on the rare but devastating progressive multifocal leukoencephalopathy (PML). Associated entities including PML associated immune reconstitution inflammatory syndrome (PML-IRIS) and the emerging phenomenon of rebound of MS disease activity after natalizumab discontinuation are also discussed. Early recognition of neuroimaging features associated with these processes is critical in order to facilitate prompt diagnosis, treatment, and/or modification of therapies to improve patient outcomes.

Risk Mitigation Strategies for Adverse Reactions Associated with the Disease-Modifying Drugs in Multiple Sclerosis

Over the past several years, the number of disease-modifying therapies (DMTs) for the treatment of multiple sclerosis (MS) has doubled in number. The 13 approved agents have shown a wide range of efficacy and safety in their clinical trials and post-marketing experience. While the availability of the newer agents allows for a wider selection of therapy for clinicians and patients, there is a need for careful understanding of the benefits and risks of each agent. Several factors such as the medication efficacy, side-effect profile, patient's preference, and co-morbidities need to be considered. An individualized treatment approach is thus imperative. In this review, risk stratification and mitigation strategies of the various disease-modifying agents are discussed.

Systematic review and meta-analysis: opportunistic infections and malignancies during treatment with anti-integrin antibodies in inflammatory bowel disease

BACKGROUND

Anti-integrin antibodies are effective therapies for Crohn's disease (CD) and ulcerative colitis (UC). However, these drugs carry theoretical risks of opportunistic infection and malignancy.

AIM

To pool data from all placebo-controlled studies, to estimate risk of opportunistic infection or malignancy with anti-integrin antibodies.

METHODS

MEDLINE, EMBASE and the Cochrane central register of controlled trials were searched (up to December 2014). Randomised placebo-controlled trials of anti-integrin antibodies in adults with active or quiescent CD or UC were eligible. Dichotomous data were pooled to obtain a relative risk (RR) of opportunistic infection or malignancy, with 95% confidence intervals (CIs).

RESULTS

The search strategy identified 1579 citations, 12 of which were eligible (four trials of natalizumab, six of vedolizumab and two of etrolizumab). The RR of developing an opportunistic infection was not significantly higher with non-gut specific (2.34; 95% CI 0.05-108.72) or gut specific anti-integrin antibodies (1.55; 95% CI 0.16-14.83). The RR was generally higher in trials of non-gut specific anti-integrin antibodies with duration of therapy ≥52 weeks (RR = 15.00; 95% CI 0.86-261), but remained non-significant. The RR of malignancy was not elevated with non-gut specific (1.57; 95% CI 0.19-12.74) or gut specific anti-integrin antibodies (0.78; 95% CI 0.15-4.02).

CONCLUSIONS

Absolute numbers of opportunistic infections were higher with anti-integrin antibodies, but this difference is not statistically significant. There was no increased risk of malignancy detected. Long-term data in large prospective cohorts are needed to further assess this issue.