Neurological adverse events of immune checkpoint inhibitors and the development of paraneoplastic neurological syndromes

Immune checkpoint inhibitors, a class of oncological treatments that enhance antitumour immunity, can trigger neurological adverse events closely resembling paraneoplastic neurological syndromes. Unlike other neurological adverse events caused by these drugs, post-immune checkpoint inhibitor paraneoplastic neurological syndromes predominantly affect the CNS and are associated with neural antibodies and cancer types commonly found also in spontaneous paraneoplastic neurological syndromes. Furthermore, post-immune checkpoint inhibitor paraneoplastic neurological syndromes have poorer neurological outcomes than other neurological adverse events of immune checkpoint inhibitors. Early diagnosis and initiation of immunosuppressive therapy are likely to be crucial in preventing the accumulation of neurological disability. Importantly, the neural antibodies found in patients with post-immune checkpoint inhibitor paraneoplastic neurological syndromes are sometimes detected before treatment, indicating that these antibodies might help to predict the development of neurological adverse events. Experimental and clinical evidence suggests that post-immune checkpoint inhibitor paraneoplastic neurological syndromes probably share immunological features with spontaneous paraneoplastic syndromes. Hence, the study of post-immune checkpoint inhibitor paraneoplastic neurological syndromes can help in deciphering the immunopathogenesis of paraneoplastic neurological syndromes and in identifying novel therapeutic targets.

Implementation of a myasthenia gravis drug-disease interaction clinical decision support tool reduces prescribing of high-risk medications

INTRODUCTION/AIMS

High-risk medication exposure is a modifiable risk factor for myasthenic exacerbation and crisis. We evaluated whether real-time electronic clinical decision support (CDS) was effective in reducing the rate of prescribing potentially high-risk medications to avoid or use with caution in patients with myasthenia gravis.

METHODS

An expert panel reviewed the available drug-disease pairings and associated severity levels to activate the alerts for CDS. All unique alerts activated in both inpatient and outpatient contexts were analyzed over a two-year period. Clinical context, alert severity, medication class, and alert action were collected. The primary outcome was alert override rate. Secondary outcomes included the percentage of unique medication exposures avoided and predictors of alert override.

RESULTS

During the analysis period, 2817 unique alerts fired, representing 830 distinct patient-medication exposures for 577 unique patients. The overall alert override rate was 85% (80.3% for inpatient alerts and 95.8% for outpatient alerts). Of unique medication-patient exposures, 19% were avoided because of the alert. Assigned alert severity of "contraindicated" were less likely to be overridden (odds ratio [OR] 0.42, 95% confidence interval [CI] 0.32-0.56), as well as alerts activated during evening staffing (OR 0.69, 95% CI 0.55-0.87).

DISCUSSION

Implementation of a myasthenia gravis drug-disease interaction alert reduced overall patient exposure to potentially harmful medications by approximately 19%. Future optimization includes enhanced provider and pharmacist education. Further refinement of alert logic criteria to optimize medication risk reduction and reduce alert fatigue is warranted to support clinicians in prescribing and reduce electronic health record time burden.

Safety and outcomes of eculizumab for acetylcholine receptor-positive generalized myasthenia gravis in clinical practice

INTRODUCTION/AIMS

Safety and outcomes data on eculizumab for generalized myasthenia gravis (gMG) in clinical practice remain limited. Outcomes and concomitant medication use may differ in practice compared with clinical trials. We analyzed the clinical and safety outcomes of patients who received eculizumab at our institutions.

METHODS

Patients with acetylcholine receptor antibody positive (AChR+) gMG, who received ≥1 dose of eculizumab and had ≥1 follow-up before December 10, 2021, were identified. Data were abstracted by chart review. Outcomes included MG Foundation of America Post Intervention Status (MGFA-PIS), Clinical Classification (MGFA-CC), MG-Activities of Daily Living (MG-ADL), concurrent immunomodulatory therapy use, and adverse events.

RESULTS

Twelve patients were included. Mean age at eculizumab initiation was 57.4 y (range, 21-77). Eight had refractory MG. Four had history of thymoma and thymectomy. A mean of 3.2 (range, 2-5) immunomodulatory therapies were previously tried. Mean follow-up duration was 18 mo (range, 2-21.6). Clinical improvement occurred rapidly; MGFA-PIS was improved in 80%, and MGFA-CC improved in 83% at 1 mo. Mean MG-ADL decreased from 8.7 to 2.8 at 1 mo, and remained ≤ 3 $$ \le 3 $$ .5 over 1.5 y. Mean daily prednisone dose decreased from 22.5 mg to 7.2 mg at 1.5 y. Five of 7 patients discontinued maintenance IVIG or PLEX. No patients had meningococcal infections and adverse events were mild.

DISCUSSION

Clinical improvement occurred in most patients after eculizumab initiation, beginning as quickly as 1 mo. Steroids were tapered and maintenance IVIG and PLEX were discontinued in most. Eculizumab had a favorable safety profile even when combined with other immunosuppressants.

The neuromuscular fellowship portal and match

For many years, Neuromuscular Medicine programs lacked a standardized means of handling fellowship applications and offering positions. Programs interviewed applicants and made offers as early as the first half of Post Graduate Year 3 (PGY3), a suboptimal timeline for applicants who may have had little prior exposure to neuromuscular or electrodiagnostic medicine. In 2021, the American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM) developed the Neuromuscular Fellowship Portal to standardize a later timeline and establish a process for fellowship applications and offers. In its first year, the Neuromuscular Fellowship Portal used a unique one-way match, in which the portal released serial offers to applicants based on rank order lists submitted by programs. Fifty-two Neuromuscular Medicine programs and seven electromyography (EMG)-focused Clinical Neurophysiology programs participated. Sixty-eight positions were filled, a similar number to previous years. A survey of fellowship directors and applicants following this process showed overwhelming support for the standardized timeline and application portal, but all program directors and most applicants favored moving to a traditional match. To maintain the existing application timeline and minimize costs for all parties, the AANEM Neuromuscular Fellowship Portal will host a two-way match, based on existing commercial match algorithms, in 2022. A match will afford a fair and efficient process for all involved. Both Neuromuscular Medicine and EMG-focused Clinical Neurophysiology programs will be encouraged to participate. The process undertaken by the AANEM can stand as an example for other neurologic subspecialties who are interested in standardizing their application timeline.

Consider Myocarditis When Patients Treated with Immune Checkpoint Inhibitors Present with Ocular Symptoms

Immune checkpoint inhibitors (ICIs) have been associated with neurological immune related adverse events (irAE-N) and patients with ICI toxicity may present with neurological or ocular symptoms. Furthermore, patients on ICI may initially present to oncology or neurology. We report a case series of 3 patients treated with ICIs presenting with diplopia or ptosis, found to have concurrent myocarditis in addition to immune-related myopathy (irMyopathy) or myasthenia gravis (irMG). None of the patients described cardiac symptoms, underscoring the importance of screening for myocarditis in patients presenting with diplopia and/or other neuromuscular symptoms which may suggest either irMyopathy or irMG.

A review of neurotoxicities associated with immunotherapy and a framework for evaluation

Immuno-oncology agents, including immune checkpoint inhibitors (ICIs) and chimeric antigen receptor T (CAR-T) cell therapies, are increasing in use for a growing list of oncologic indications. While harnessing the immune system against cancer cells has a potent anti-tumor effect, it can also cause widespread autoimmune toxicities that limit therapeutic potential. Neurologic toxicities have unique presentations and can progress rapidly, necessitating prompt recognition. In this article, we review the spectrum of central and peripheral neurologic immune-related adverse events (irAEs) associated with ICI therapies, emphasizing a diagnostic framework that includes consideration of the therapy regimen, timing of symptom onset, presence of non-neurologic irAEs, pre-existing neurologic disease, and syndrome specific features. In addition, we review the immune effector cell-associated neurotoxicity syndrome (ICANS) associated with CAR-T cell therapy and address diagnostic challenges specific to patients with brain metastases. As immunotherapy use grows, so too will the number of patients affected by neurotoxicity. There is an urgent need to understand pathogenic mechanisms, predictors, and optimal treatments of these toxicities, so that we can manage them without sacrificing anti-tumor efficacy.

Association between incidental statin use and skeletal myopathies in patients treated with immune checkpoint inhibitors

Objectives

Skeletal myopathies are highly morbid, and in rare cases even fatal, immune-related adverse events (irAE) associated with immune checkpoint inhibitors (ICI). Skeletal myopathies are also a recognized statin-associated side effect. It is unknown whether concurrent use of statins and ICIs increases the risk of skeletal myopathies.

Methods

This was a retrospective cohort study of all patients who were treated with an ICI at a single academic institution (Massachusetts General Hospital, Boston, MA, USA). The primary outcome of interest was the development of a skeletal myopathy. The secondary outcome of interest was an elevated creatine kinase level (above the upper limit of normal).

Results

Among 2757 patients, 861 (31.2%) were treated with a statin at the time of ICI start. Statin users were older, more likely to be male and had a higher prevalence of cardiovascular and non-cardiovascular co-morbidities. During a median follow-up of 194 days (inter quartile range 65–410), a skeletal myopathy occurred in 33 patients (1.2%) and was more common among statin users (2.7 vs. 0.9%, P < 0.001). Creatine kinase (CK) elevation was present in 16.3% (114/699) and was higher among statin users (20.0 vs. 14.3%, P = 0.067). In a multivariable Cox model, statin therapy was associated with a >2-fold higher risk for skeletal myopathy (HR, 2.19; 95% confidence interval, 1.07–4.50; P = 0.033).

Conclusion

In this large cohort of ICI-treated patients, a higher risk was observed for skeletal myopathies and elevation in CK levels in patients undergoing concurrent statin therapy. Prospective observational studies are warranted to further elucidate the potential association between statin use and ICI-associated myopathies.

Effect of a multidisciplinary Severe Immunotherapy Complications Service on outcomes for patients receiving immune checkpoint inhibitor therapy for cancer

BACKGROUND

In 2017, Massachusetts General Hospital implemented the Severe Immunotherapy Complications (SIC) Service, a multidisciplinary care team for patients hospitalized with immune-related adverse events (irAEs), a unique spectrum of toxicities associated with immune checkpoint inhibitors (ICIs). This study's objectives were to evaluate the intervention's (1) effect on patient outcomes and healthcare utilization, and (2) ability to collect biological samples via a central infrastructure, in order to study the mechanisms responsible for irAEs.

METHODS

A hospital database was used to identify patients who received ICIs for a malignancy and were hospitalized with severe irAEs, before (April 2, 2016-October 3, 2017) and after (October 3, 2017-October 24, 2018) SIC Service initiation. The primary outcome was readmission rate after index hospitalization. Secondary outcomes included length of stay (LOS) for admissions, corticosteroid and non-steroidal second-line immunosuppression use, ICI discontinuation, and inpatient mortality.

RESULTS

In the pre-SIC period, 127 of 1169 patients treated with ICIs were hospitalized for irAEs; in the post-SIC period, 122 of 1159. After SIC service initiation, reductions were observed in irAE readmission rate (14.8% post-SIC vs 25.9% pre-SIC; OR 0.46; 95% CI 0.22 to 0.95; p=0.036) and readmission LOS (median 6 days post-SIC vs 7 days pre-SIC; 95% CI -16.03 to -0.14; p=0.046). No significant pre-initiation and post-initiation differences were detected in corticosteroid use, second-line immunosuppression, ICI discontinuation, or inpatient mortality rates. The SIC Service collected 789 blood and tissue samples from 234 patients with suspected irAEs.

CONCLUSIONS

This is the first study to report that establishing a highly subspecialized care team focused on irAEs is associated with improved patient outcomes and reduced healthcare utilization. Furthermore, the SIC Service successfully integrated blood and tissue collection safety into routine care.

Retrospective analysis of safety and outcomes of rituximab for myasthenia gravis in patients ≥65 years old

INTRODUCTION/AIMS

Optimal management of myasthenia gravis (MG) in individuals ≥65 y old is unknown and patient factors may limit therapeutic choices. Safety and efficacy of rituximab in older patients with MG has not been well-studied.

METHODS

This retrospective study examined 40 patients (14 patients ≥65 y old) treated with rituximab for MG. The primary efficacy outcome was the proportion of patients reaching "Improved" or better on Myasthenia Gravis Foundation of America (MGFA) Post-Intervention Status (PIS) at 12 mo, compared between younger and older patients.

RESULTS

Ninety-two percent of patients ≥65 y old achieved MGFA PIS Improved or better at 12 mo compared to 69% of those <65 y old (P = .11). Median prednisone dose for the cohort decreased in the year following rituximab initiation (20 mg [interquartile range, 10-35] to 10 mg [0-13], P = .01). Non-refractory MG was predictive of favorable outcome, whereas age was not. Serious adverse events (SAEs) were similar between older and younger patients (21.4% vs. 30.8%, P = .715). No patients ≥65 y old required discontinuation of rituximab due to SAE. One death occurred in a patient <65 y old due to systemic inflammatory response syndrome.

DISCUSSION

At 12 mo following initiation of rituximab for MG, patients ≥65 y old experienced similarly high rates of improvement in their myasthenic symptoms as younger patients, without an increased risk of experiencing SAEs. Rituximab should be considered in the treatment paradigm in older patients and in non-refractory MG patients of any age.

Telemedicine visits in myasthenia gravis: Expert guidance and the Myasthenia Gravis Core Exam (MG-CE)

INTRODUCTION/AIMS

Telemedicine may be particularly well-suited for myasthenia gravis (MG) due to the disorder's need for specialized care, its hallmark fluctuating muscle weakness, and the potential for increased risk of virus exposure among patients with MG during the coronavirus disease 2019 (COVID-19) pandemic during in-person clinical visits. A disease-specific telemedicine physical examination to reflect myasthenic weakness does not currently exist.

METHODS

This paper outlines step-by-step guidance on the fundamentals of a telemedicine assessment for MG. The Myasthenia Gravis Core Exam (MG-CE) is introduced as a MG-specific, telemedicine, physical examination, which contains eight components (ptosis, diplopia, facial strength, bulbar strength, dysarthria, single breath count, arm strength, and sit to stand) and takes approximately 10 minutes to complete.

RESULTS

Pre-visit preparation, remote ascertainment of patient-reported outcome scales and visit documentation are also addressed.

DISCUSSION

Additional knowledge gaps in telemedicine specific to MG care are identified for future investigation.

Immune-related adverse events associated with immune checkpoint inhibitors: a call to action for collecting and sharing clinical trial and real-world data

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of cancer, improving outcomes in patients with advanced malignancies. The use of ICIs in clinical practice, and the number of ICI clinical trials, are rapidly increasing. The use of ICIs in combination with other forms of cancer therapy, such as chemotherapy, radiotherapy, or targeted therapy, is also expanding. However, immune-related adverse events (irAEs) can be serious in up to a third of patients. Critical questions remain surrounding the characteristics and outcomes of irAEs, and how they may affect the overall risk-benefit relationship for combination therapies. This article proposes a framework for irAE classification and reporting, and identifies limitations in the capture and sharing of data on irAEs from current clinical trial and real-world data. We outline key gaps and suggestions for clinicians, clinical investigators, drug sponsors, patients, and other stakeholders to make these critical data more available to researchers for pooled analysis, to advance contemporary understanding of irAEs, and ultimately improve the efficacy of ICIs.

Consensus disease definitions for neurologic immune-related adverse events of immune checkpoint inhibitors

Expanding the US Food and Drug Administration-approved indications for immune checkpoint inhibitors in patients with cancer has resulted in therapeutic success and immune-related adverse events (irAEs). Neurologic irAEs (irAE-Ns) have an incidence of 1%-12% and a high fatality rate relative to other irAEs. Lack of standardized disease definitions and accurate phenotyping leads to syndrome misclassification and impedes development of evidence-based treatments and translational research. The objective of this study was to develop consensus guidance for an approach to irAE-Ns including disease definitions and severity grading. A working group of four neurologists drafted irAE-N consensus guidance and definitions, which were reviewed by the multidisciplinary Neuro irAE Disease Definition Panel including oncologists and irAE experts. A modified Delphi consensus process was used, with two rounds of anonymous ratings by panelists and two meetings to discuss areas of controversy. Panelists rated content for usability, appropriateness and accuracy on 9-point scales in electronic surveys and provided free text comments. Aggregated survey responses were incorporated into revised definitions. Consensus was based on numeric ratings using the RAND/University of California Los Angeles (UCLA) Appropriateness Method with prespecified definitions. 27 panelists from 15 academic medical centers voted on a total of 53 rating scales (6 general guidance, 24 central and 18 peripheral nervous system disease definition components, 3 severity criteria and 2 clinical trial adjudication statements); of these, 77% (41/53) received first round consensus. After revisions, all items received second round consensus. Consensus definitions were achieved for seven core disorders: irMeningitis, irEncephalitis, irDemyelinating disease, irVasculitis, irNeuropathy, irNeuromuscular junction disorders and irMyopathy. For each disorder, six descriptors of diagnostic components are used: disease subtype, diagnostic certainty, severity, autoantibody association, exacerbation of pre-existing disease or de novo presentation, and presence or absence of concurrent irAE(s). These disease definitions standardize irAE-N classification. Diagnostic certainty is not always directly linked to certainty to treat as an irAE-N (ie, one might treat events in the probable or possible category). Given consensus on accuracy and usability from a representative panel group, we anticipate that the definitions will be used broadly across clinical and research settings.

Temporal Trends and Outcomes Among Patients Admitted for Immune-Related Adverse Events: A Single-Center Retrospective Cohort Study from 2011 to 2018

BACKGROUND

The aim of this study was to characterize severe immune-related adverse events (irAEs) seen among hospitalized patients and to examine risk factors for irAE admissions and clinically relevant outcomes, including length of stay, immune checkpoint inhibitor (ICI) discontinuation, readmission, and death.

METHODS

Patients who received ICI therapy (ipilimumab, pembrolizumab, nivolumab, atezolizumab, durvalumab, avelumab, or any ICI combination) at Massachusetts General Hospital (MGH) and were hospitalized at MGH following ICI initiation between January 1, 2011, and October 24, 2018, were identified using pharmacy and hospital admission databases. Medical records of all irAE admissions were reviewed, and specialist review with defined criteria was performed. Demographic data, relevant clinical history (malignancy type and most recent ICI regimen), and key admission characteristics, including dates of admission and discharge, immunosuppressive management, ICI discontinuation, readmission, and death, were collected.

RESULTS

In total, 450 admissions were classified as irAE admissions and represent the study's cohort. Alongside the increasing use of ICIs at our institution, the number of patients admitted to MGH for irAEs has gradually increased every year from 9 in 2011 to 92 in 2018. The hospitalization rate per ICI recipient has declined over that same time period (25.0% in 2011 to 8.5% in 2018). The most common toxicities leading to hospitalization in our cohort were gastrointestinal (30.7%; n = 138), pulmonary (15.8%; n = 71), hepatic (14.2%; n = 64), endocrine (12.2%; n = 55), neurologic (8.4%; n = 38), cardiac (6.7%; n = 30), and dermatologic (4.4%; n = 20). Multivariable logistic regression revealed statistically significant increases in irAE admission risk for CTLA-4 monotherapy recipients (odds ratio [OR], 2.02; p < .001) and CTLA-4 plus PD-1 combination therapy recipients (OR, 1.88; p < .001), relative to PD-1/PD-L1 monotherapy recipients, and patients with multiple toxicity had a 5-fold increase in inpatient mortality.

CONCLUSION

This study illustrates that cancer centers must be prepared to manage a wide variety of irAE types and that CTLA-4 and combination ICI regimens are more likely to cause irAE admissions, and earlier. In addition, admissions for patients with multi-organ involvement is common and those patients are at highest risk of inpatient mortality.

IMPLICATIONS FOR PRACTICE

The number of patients admitted to Massachusetts General Hospital for immune-related adverse events (irAEs) has gradually increased every year and the most common admissions are for gastrointestinal (30.7%), pulmonary (15/8%), and hepatic (14.2%) events. Readmission rates are high (29% at 30 days, 49% at 180 days) and 64.2% have to permanently discontinue immune checkpoint inhibitor therapy. Importantly, multiple concurrent toxicities were seen in 21.6% (97/450) of irAE admissions and these patients have a fivefold increased risk of inpatient death.

Impact of multidisciplinary severe immunotherapy complication service on outcomes for cancer patients receiving immune checkpoint inhibition

2654

Background: The exponential increase in FDA-approved indications for immune checkpoint inhibitors (ICI) in cancer care has resulted in therapeutic success but also in the occurrence of immune-related adverse effects (irAEs) that can represent a significant clinical challenge. On October 3 2017, the Massachusetts General Hospital (MGH) implemented the Severe Immunotherapy Complications (SIC) Service, a multi-disciplinary care team for patients hospitalized with irAEs. The objectives of this study were to evaluate the impact of SIC Service on 1) healthcare utilization and 2) patients outcomes. Methods: Using pharmacy and hospital admission databases, a list of patients was identified that both received ICI for a malignancy and were hospitalized with severe irAEs in the period prior to initiation of the SIC service and after SIC initiation. The pre-SIC period was defined as an admission between 4/2/2016 through 10/3/2017, and the post-SIC period as an admission from 10/3/2017 through 10/24/2018. The rate of readmission after the index hospitalization was the primary outcome. Secondary outcomes included lengths of stay (LOS) for both initial irAE admissions and readmissions, use of corticosteroids and non-steroidal second-line immunosuppression, ICI discontinuation, and inpatient mortality in the pre- and post-SIC periods. Results: Among 1169 patients treated in the pre-SIC service intervention period; 127 were hospitalized for irAE. Among 1159 patients treated in the post-SIC intervention 122 were hospitalized for irAE. SIC Service implementation was associated with a significant reduction in irAE readmission rates (post-SIC 14.8% vs. pre-SIC 25.9%; odds ratio [OR], 0.46; 95% CI, 0.22-0.95; p=0.036). The length of stay, rates of corticosteroid use, second-line immunosuppression, and ICI discontinuation for irAE, as well as inpatient mortality rates were not significantly different before and after SIC Service implementation. Conclusions: This is the first study to report that establishing a highly subspecialized care team focused on irAEs can be associated with improved clinical outcomes for patients receiving ICI therapy. Such care teams may play an essential part in optimizing irAE care.

Consensus disease definitions for the spectrum of neurologic immune related adverse events

2647

Background: Expanding FDA-approved indications for immune checkpoint inhibitors in patients with cancer has resulted in both therapeutic success and immune related adverse events (irAEs). Neurologic irAEs (irAE-Ns) have an incidence of 1-12% and a high fatality rate relative to other irAEs. Lack of standardized disease definitions and accurate phenotyping leads to syndrome misclassification and impedes evidence-based treatments and research progress. The objectives of this study were to develop consensus guidance for an approach to irAE-Ns including disease definitions and severity grading. Methods: A working group of 4 neurologists drafted irAE-N consensus guidance and definitions, which were reviewed by the Neuro irAE Disease Definition Panel, consisting of neurologists, oncologists, neuro-oncologists and irAE subspecialists. A modified Delphi consensus process was used, with 2 rounds of anonymous ratings by panelists and 2 virtual meetings to discuss areas of controversy. Panelists rated content for usability, appropriateness and accuracy on 9-point scales in electronic surveys and provided free text comments. The working group aggregated survey responses and incorporated them into revised definitions. Consensus was based on numeric ratings using the RAND/UCLA Appropriateness Method with prespecified definitions. Results: Twenty-seven panelists from 15 academic medical centers voted on a total of 53 rating scales (6 general guidance, 24 central and 18 peripheral nervous system disease definition components, 3 severity criteria and 2 clinical trial adjudication statements); of these, 77% (41/53) received first round consensus. After revisions, all items received second round consensus. Consensus definitions were achieved for 7 core disorders: irMeningitis, irEncephalitis/Encephalomyelitis, irDemyelinating disease, irVasculitis, irNeuropathy, irNeuromuscular junction disorders and irMyopathy. For each disorder, 6 sub-classifications are described: disease subtype, diagnostic certainty, severity, autoantibody association, exacerbation of pre-existing disease or de novo presentation and present or absent concurrent irAE. Conclusions: These disease definitions standardize irAE-N classification. They are being incorporated into a multi-institutional registry that our group has initiated to study irAEs. Given consensus on their accuracy and usability from a representative panel group, we anticipate that they can be used broadly across clinical and research settings.

COVID-19 in patients with myasthenia gravis

INTRODUCTION

Coronavirus disease 2019 (COVID-19) has rapidly become a global pandemic, but little is known about its potential impact on patients with myasthenia gravis (MG).

METHODS

We studied the clinical course of COVID-19 in five hospitalized patients with autoimmune MG (four with acetylcholine receptor antibodies, one with muscle-specific tyrosine kinase antibodies) between April 1, 2020-April 30-2020.

RESULTS

Two patients required intubation for hypoxemic respiratory failure, whereas one required significant supplemental oxygen. One patient with previously stable MG had myasthenic exacerbation. One patient treated with tocilizumab for COVID-19 was successfully extubated. Two patients were treated for MG with intravenous immunoglobulin without thromboembolic complications.

DISCUSSION

Our findings suggest that the clinical course and outcomes in patients with MG and COVID-19 are highly variable. Further large studies are needed to define best practices and determinants of outcomes in this unique population.

Lambert-Eaton Myasthenic Syndrome, Botulism, and Immune Checkpoint Inhibitor-Related Myasthenia Gravis

PURPOSE OF REVIEW

This article reviews the pathophysiology, epidemiology, clinical presentation, diagnosis, and treatment of Lambert-Eaton myasthenic syndrome (LEMS) and of botulism, and immune-related myasthenia gravis (MG) occurring in the context of immune checkpoint inhibitor therapy for cancer.

RECENT FINDINGS

The suspicion that LEMS is rare but also likely underdiagnosed is supported by recent epidemiologic data. A validated, LEMS-specific scale now exists to assess and monitor disease, and symptomatic and immunomodulatory treatments are available. As presynaptic disorders of neuromuscular transmission, LEMS and botulism share electrodiagnostic abnormalities but have important distinguishing features. Knowledge of the clinical features of botulism is needed, particularly with continued cases of infant botulism, the opioid epidemic increasing the incidence of wound botulism, and medical use of botulinum toxin, which may cause iatrogenic botulism. Foodborne botulism remains rare. Prompt recognition of botulism and administration of antitoxin can improve outcomes. MG may be exacerbated or may present de novo in the context of immune activation from immune checkpoint inhibitor therapies for cancer. Immune-related MG commonly overlaps with myositis and myocarditis. Corticosteroids typically result in improvement. However, immune-related MG can be more fulminant than its idiopathic counterpart and may cause permanent disability or death.

SUMMARY

The diagnosis of LEMS, botulism, or immune-related MG can generally be made from the patient's history, supplemented with directed questions, a physical examination designed to demonstrate abnormalities, and laboratory and electrodiagnostic testing. Early diagnosis and carefully selected treatment not only improve outcomes of the neuromuscular disease but can affect the prognosis of underlying malignancy, when present.

COVID-19 and neuromuscular disorders

The coronavirus 2019 (COVID-19) pandemic has potential to disproportionately and severely affect patients with neuromuscular disorders. In a short period of time, it has already caused reorganization of neuromuscular clinical care delivery and education, which will likely have lasting effects on the field. This article reviews (1) potential neuromuscular complications of COVID-19, (2) assessment and mitigation of COVID-19-related risk for patients with preexisting neuromuscular disease, (3) guidance for management of immunosuppressive and immunomodulatory therapies, (4) practical guidance regarding neuromuscular care delivery, telemedicine, and education, and (5) effect on neuromuscular research. We outline key unanswered clinical questions and highlight the need for team-based and interspecialty collaboration. Primary goals of clinical research during this time are to develop evidence-based best practices and to minimize morbidity and mortality related to COVID-19 for patients with neuromuscular disorders.

Severe Neurological Toxicity of Immune Checkpoint Inhibitors: Growing Spectrum

Expanding use of immune-checkpoint inhibitors (ICIs) underscores the importance of accurate diagnosis and timely management of neurological immune-related adverse events (irAE-N). We evaluate the real-world frequency, phenotypes, co-occurring immune-related adverse events (irAEs), and long-term outcomes of severe, grade III to V irAE-N at a tertiary care center over 6 years. We analyze how our experience supports published literature and professional society guidelines. We also discuss these data with regard to common clinical scenarios, such as combination therapy, ICI rechallenge and risk of relapse of irAE-N, and corticosteroid taper, which are not specifically addressed by current guidelines and/or have limited data. Recommendations for management and future irAE-N reporting are outlined. ANN NEUROL 2020;87:659-669.

Immune-Related Adverse Events in the Setting of PD-1/L1 Inhibitor Combination Therapy

In 2018, a multi‐disciplinary workshop was held at the Massachusetts General Hospital to discuss challenges in defining, diagnosing, and treating immune‐related adverse events (irAE), including those that occur in patients administered PD‐1/L1 inhibitor combination therapy. In this commentary, the workshop participants present a clinical case that illustrates the complexity of irAE diagnosis and management in a patient receiving PD‐1/L1 combination therapy, summarize the current state of PD‐1/L1 combination therapy, and discuss challenges and opportunities for the evaluation of irAEs as these combinations become more widely used to treat patients with cancer.

Varied phenotypes and management of immune checkpoint inhibitor-associated neuropathies

OBJECTIVE

To describe the spectrum, clinical course, and management of neuropathies associated with immune checkpoint inhibitors (ICIs).

METHODS

Patients with ICI-related neuropathy (irNeuropathy) were identified and their clinical characteristics compared to neuropathy attributed to cytotoxic agents.

RESULTS

We identified 19 patients with irNeuropathies. ICIs included anti-programmed death-1 (PD1), 9; anti-cytotoxic T-lymphocyte-associated antigen-4 (CTLA4), 2; and combination of anti-CTLA4 and anti-PD1, 8. Median number of ICI doses prior to neuropathy onset was 4. Rate of neuropathies following ICI therapy was 0.7%. Underlying malignancies included melanoma (n = 15), lung adenocarcinoma (n = 3), and cholangiocarcinoma (n = 1). Neuropathy phenotypes were cranial neuropathies with or without meningitis (n = 7), nonlength-dependent polyradiculoneuropathies with and without cranial nerve involvement (n = 6), small-fiber/autonomic neuropathy (n = 2), ANCA-associated mononeuritis multiplex (n = 1), sensory neuronopathy (n = 1), length-dependent sensorimotor axonal polyneuropathy (n = 1), and neuralgic amyotrophy (n = 1). Immune-related adverse events involving other organ systems were common (58%). Corticosteroid use for management of neuropathy was associated with improvement in median modified Rankin Scale score (1 vs 0, p = 0.001) and Inflammatory Neuropathy Cause and Treatment Disability score (2 vs 0.5, p = 0.012) (Class IV). Significantly higher proportion of irNeuropathies had acute or subacute and nonlength-dependent presentations (p < 0.001) and rate of hospitalization for irNeuropathy was also higher (p = 0.002) compared to toxic neuropathy from chemotherapy.

CONCLUSION

Neuropathy is a rare complication of ICIs that often responds to immunosuppression. Recognition of its wide phenotypic spectrum and distinct clinical characteristics and prompt management with corticosteroids may lead to favorable outcomes.

A case report of clonal EBV-like memory CD4+ T cell activation in fatal checkpoint inhibitor-induced encephalitis

Checkpoint inhibitors produce durable responses in numerous metastatic cancers, but immune-related adverse events (irAEs) complicate and limit their benefit. IrAEs can affect organ systems idiosyncratically; presentations range from mild and self-limited to fulminant and fatal. The molecular mechanisms underlying irAEs are poorly understood. Here, we report a fatal case of encephalitis arising during anti-programmed cell death receptor 1 therapy in a patient with metastatic melanoma. Histologic analyses revealed robust T cell infiltration and prominent programmed death ligand 1 expression. We identified 209 reported cases in global pharmacovigilance databases (across multiple cancer types) of encephalitis associated with checkpoint inhibitor regimens, with a 19% fatality rate. We performed further analyses from the index case and two additional cases to shed light on this recurrent and fulminant irAE. Spatial and multi-omic analyses pinpointed activated memory CD4⁺ T cells as highly enriched in the inflamed, affected region. We identified a highly oligoclonal T cell receptor repertoire, which we localized to activated memory cytotoxic (CD45RO⁺GZMB⁺Ki67⁺) CD4 cells. We also identified Epstein-Barr virus-specific T cell receptors and EBV⁺ lymphocytes in the affected region, which we speculate contributed to neural inflammation in the index case. Collectively, the three cases studied here identify CD4⁺ and CD8⁺ T cells as culprits of checkpoint inhibitor-associated immune encephalitis.

Diagnosis and Management of Immune Checkpoint Inhibitor-Associated Neurologic Toxicity: Illustrative Case and Review of the Literature

Immune checkpoint inhibitors (ICIs) initiate antitumor immunity by blocking the action of immune inhibitor-signaled cytotoxic proteins, such as cytotoxic T-lymphocyte-associated protein 4, programmed cell death protein 1, and programmed cell death ligand 1. However, in rare cases (∼1%-12% of patients), ICI treatment causes neurologic immune-related adverse events (irAEs). These include, but are not limited to, headache, encephalitis, neuropathies, myasthenia gravis, and myositis. The symptoms associated with irAEs can range from mild (grade 1-2) to severe (grade 3-4); however, they are often challenging to diagnose because they may present as generalized symptoms, such as fatigue and weakness, that can also be caused by the cancer itself. Here, we present an illustrative case of a 67-year-old woman who presented with signs of a neurologic irAE, including progressive dysphagia and weakness leading to falls, which started during treatment with pembrolizumab and worsened following initiation of ipilimumab. Following neurological and pathological evaluation, she was diagnosed with myositis. She was treated with steroids and improved rapidly. In this article, we review previous literature to provide guidance to frequently asked questions concerning the diagnosis and management of neurologic irAEs in patients with advanced cancer. With prompt and effective treatment, most patients will achieve a complete recovery. KEY POINTS: Neurologic immune-related adverse events (irAEs) affect approximately 1% of patients treated with immune checkpoint inhibitor (ICI) monotherapy and 2%-3% treated with combination therapy. These irAEs can affect any portion of the nervous system, although peripheral nerve system manifestations are most common. Overlap syndromes with multiple neurologic irAEs or other affected organ systems frequently exist.Diagnosis of neurologic irAEs can be challenging. Routine testing may be unremarkable and symptoms frequently mimic those from cancer or side effects of other therapies. Optimal management is currently unknown. A systematic, highly coordinated, and multidisciplinary approach is critical.Outcomes from neurologic irAEs are typically favorable with the current practice of holding the ICI and starting corticosteroids. Some patients are even successfully retreated with an ICI. A subset of patients, however, have a fulminant and potentially fatal course.Improved risk assessments and targeted therapies are needed.

Characterization of B cells in muscle-specific kinase antibody myasthenia gravis

OBJECTIVE

To characterize B-cell subsets in patients with muscle-specific tyrosine kinase (MuSK) myasthenia gravis (MG).

METHODS

In accordance with Human Immunology Project Consortium guidelines, we performed polychromatic flow cytometry and ELISA assays in peripheral blood samples from 18 patients with MuSK MG and 9 healthy controls. To complement a B-cell phenotype assay that evaluated maturational subsets, we measured B10 cell percentages, plasma B cell-activating factor (BAFF) levels, and MuSK antibody titers. Immunologic variables were compared with healthy controls and clinical outcome measures.

RESULTS

As expected, patients treated with rituximab had high percentages of transitional B cells and plasmablasts and thus were excluded from subsequent analysis. The remaining patients with MuSK MG and controls had similar percentages of total B cells and naïve, memory, isotype-switched, plasmablast, and transitional B-cell subsets. However, patients with MuSK MG had higher BAFF levels and lower percentages of B10 cells. In addition, we observed an increase in MuSK antibody levels with more severe disease.

CONCLUSIONS

We found prominent B-cell pathology in the distinct form of MG with MuSK autoantibodies. Increased BAFF levels have been described in other autoimmune diseases, including acetylcholine receptor antibody-positive MG. This finding suggests a role for BAFF in the survival of B cells in MuSK MG, which has important therapeutic implications. B10 cells, a recently described rare regulatory B-cell subset that potently blocks Th1 and Th17 responses, were reduced, which suggests a potential mechanism for the breakdown in immune tolerance in patients with MuSK MG.

Peripheral neuropathies in pregnancy

PURPOSE OF REVIEW

This article provides an overview of the most common peripheral neuropathic disorders in pregnancy with a focus on clinical recognition, diagnosis, and treatment.

RECENT FINDINGS

The literature on this topic consists primarily of case reports, case series, and retrospective reviews. Recent work, particularly in carpal tunnel syndrome, brachial neuritis, and inherited neuropathies in pregnancy, has added to our knowledge of this field. Awareness of diabetic polyneuropathy with associated autonomic dysfunction in pregnancy has grown as the incidence of diabetes mellitus increases in women of childbearing age.

SUMMARY

Women may develop mononeuropathy, plexopathy, radiculopathy, or polyneuropathy during pregnancy or postpartum. Pregnancy often influences consideration of etiology, treatment, and prognosis. In women of childbearing age with known acquired or genetic neuromuscular disorders, pregnancy should be anticipated and appropriate counseling provided. An interdisciplinary approach with other medical specialties is often necessary.

Abstract P32: Potential Underuse of Antidepressants in Post Stroke Depression: Data From the AVAIL Registry

Background: Post-stroke depression is common, yet little is known about factors associated with antidepressant use in this population

Methods: Data from the multicenter, prospective Adherence eValuation After Ischemic stroke-Longitudinal (AVAIL) registry was used to identify patients with post-stroke depression and to describe factors associated with antidepressant use. The analysis was performed after 3 months in 1751 ischemic stroke patients who had been admitted to 97 hospitals nationwide; 12 month follow-up was available for 1637 patients. The Get with the Guidelines-Stroke database was used to collect baseline data. Patients were classified as depressed based on a self-report scale (the Patient Health Questionnaire-8; score range 0 to 24, score ≥10 indicating depression). Frequencies were compared with Pearson X 2 and unadjusted ORs were calculated.

Results: The prevalence of post stroke depression was similar at 3 and 12 months (19% [331/1751] vs 17% [280/1637], respectively, p=0.17). Regardless of depression status, antidepressant use was higher at 12 months (16% [287/1751] vs 20% [334/1637], p=0.002). Antidepressant use was also higher at 12 months in depressed patients (25% [84/331] vs 35% [98/280], p=0.009). The odds of antidepressant use at 3 months was higher in women than men (OR 1.6, 95% CI 1.2-2.1), Whites vs. Blacks (OR 1.7, 95% CI 1.1-2.8), in patients with vs. without cognitive deficits (OR 1.6, 95% CI 1.2-2.1) and in those with more severe disabilities (mRS≥3 vs. mRS<3, OR 1.7, 95% CI 1.3-2.3). Use did not vary with educational level, marital status, living situation, medication insurance coverage, or stroke recurrence. Similar trends were present at 12 months, except with higher use in those with recurrent stroke or TIA (OR 2.1, 95% CI 1.4-3.1).

Conclusion: Three-quarters of depressed stroke patients at 3-months and nearly two-thirds at 12 months were not receiving antidepressants. Regardless of depression status, utilization of antidepressants after 3 and 12 months varied based on gender, race/ethnicity, cognitive status, disability level, and after 12-months, stroke recurrence. The reasons for the apparent underuse of antidepressants in patients with prevalent post-stroke depression require further study.