Immune Checkpoint Inhibitor-Related Cerebellar Toxicity: Clinical Features and Comparison with Paraneoplastic Cerebellar Ataxia.

Immune checkpoint inhibitors (ICIs) have revolutionized cancer therapy, and the association with immune-related adverse events (irAEs) is well-established. However, cerebellar irAEs are poorly defined and their relationship with paraneoplastic disorders remains unclear. Our aim was (i) to characterize cerebellar irAE; (ii) to compare it with paraneoplastic cerebellar ataxia (PCA). We performed a multicenter, retrospective, cohort study of patients developing new-onset, immune-mediated, isolated/predominant cerebellar dysfunction after ICI administration. In addition, a systematic review following PRISMA guidelines was performed. Cerebellar irAE cases were compared with a consecutive cohort of patients with PCA. Overall, 35 patients were included, of whom 12 were original cases (males: 25/35 (71%), median age: 65 [range: 20-82]). The most frequent tumor was non-small cell lung cancer (12/35, 34%). Anti-PD1 were adopted in 19/35 (54%). Symptoms developed at a median of 11 weeks after ICI onset. Neuronal antibodies were detected in 15/31 patients tested (48%). Cerebrospinal fluid was inflammatory in 25/30 (83%). Magnetic resonance imaging showed cerebellar hyperintensities in 8/35 (23%). Immunotherapy was applied in 33/35 cases (94%), and most patients improved with residual disability (16/35, 46%). When compared with a series of PCA (n = 15), the cerebellar irAE group was significantly more associated with male sex, lung cancer (rather than gynecological/breast cancers), isolated ataxia, and a better outcome. We provide a detailed characterization of cerebellar irAE. Compared to PCA, differences exist in terms of tumor association, clinical features, and outcome. Clinical presentation-antibody-tumor triad in the ICI group only partially reflects the associations described in paraneoplastic disorders.

Beyond T cell toxicity - Intrathecal chemokine CXCL13 indicating B cell involvement in immune-related adverse events following checkpoint inhibition: A two-case series and literature review.

BACKGROUND AND PURPOSE: This study was undertaken to raise awareness of a role of B cells in immune checkpoint inhibitor (ICI)-associated neurological immune-related adverse events (nirAE). METHODS: A systematic literature review was made, with case observations of a melanoma and a non-small cell lung cancer (NSCLC) patient who developed ICI-associated nirAE with cerebrospinal fluid (CSF) findings indicating B cell involvement. RESULTS: Two patients receiving ipilimumab/nivolumab for melanoma and chemotherapy/pembrolizumab for NSCLC developed nirAE in the form of myocarditis/myositis/myasthenia gravis overlap syndrome (triple M) and cerebellitis plus longitudinal transverse myelitis (c-LETM), respectively. Intrathecal inflammation with chemokine C-X-C motif ligand (CXCL13) elevation was present in both patients; the triple M case had acetylcholine receptor antibodies, antititin reactivity, altered CD4/CD8 T cell ratio in blood, and depressed programmed death-1 (PD-1) expression on CSF T cells; the c-LETM case showed intrathecal antibody production and plasma cells. Both patients insufficiently responded to first-line treatment. The NSCLC case improved upon administration of B cell-depleting therapy with rituximab, whereas the melanoma patient died before escalation therapy was initiated. Literature research revealed one additional ICI-associated LETM case with intrathecal CXCL13 elevation, three cases with ICI-associated aquaporin-4 antibody neuromyelitis spectrum disorder, and evidence of B cell-mediated toxicity based on antibody-mediated immune pathologies in ICI-associated immune-related adverse events. CONCLUSIONS: The case observations highlight the plethora of uncertainties in diagnosis and treatment of ICI-associated nirAE, exemplify the heterogeneity of immune mechanisms involved, and suggest a role of B cells, which may be underdiagnosed. Intrathecal CXCL13 may serve as a biomarker of B cell involvement in nirAE, supported by intrathecal immunoglobulin synthesis, presence of plasma cells, and/or recruitment of cognate immune cells.

The Impact of COVID-19 and Vaccine on the Human Nervous System.

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has precipitated a global health crisis of unprecedented proportions. Due to its severe impact, multiple COVID-19 vaccines are being developed, approved, and manufactured rapidly. However, some serious adverse events (AEs) were reported after the application of them, significantly increasing concerns about the safety and efficacy of the vaccines and doubts about the necessity of vaccination. Particularly, previous vaccination campaigns have shown us that partial vaccination can induce neurologic AEs. Herein, we discuss in depth the involvement of the nervous system during SARS-CoV-2 infection or after vaccination. On the one hand, COVID-19 could pose an enormous threat to human neurological health through direct infection and indirect neurotoxicity effects. On the other hand, our review indicated that only a few serious neurological AEs following vaccination occurred and among which headache was the most common. Moreover, some neurological AEs do not seem to be related to vaccination. Of course, the causal relationships between several vaccines and AEs are considered plausible, and it is not doubtful that these AEs should be taken seriously by clinicians in assessing the potential risks and benefits of vaccinations in special populations. Nevertheless, in the case of the rapid spread of COVID-19, the potential side effects of vaccination on the nervous system should be compared with adverse COVID-19 outcomes rather than being considered alone. Thus, it is obviously a wise option to be vaccinated instead of suffering from serious adverse symptoms of virus infection.

Central nervous system complications associated with immune checkpoint inhibitors.

OBJECTIVE: To describe the spectrum and outcome of central nervous system complications associated with immune checkpoint inhibitors (CNS-ICI). METHODS: Patients with CNS-ICI were identified and their characteristics compared with ICI-related peripheral neuropathy (PN-ICI). RESULTS: We identified 19 patients with CNS-ICI. The patients were receiving nivolumab (n=8), pembrolizumab (n=6), a combination of ipilimumab-nivolumab (n=3), ipilimumab-durvalumab (n=1), or atezolizumab (n=1). Underlying malignancies included non-small-cell lung cancer (n=8), melanoma (n=3), and other less common tumours (n=8). Neurological phenotypes were limbic encephalitis (n=8), meningoencephalitis (n=4) and cerebellitis (n=4). Two patients developed isolated confusion and one parkinsonism. Associated autoantibodies included onconeural (Ma2, n=7; Hu, n=1), astrocytic (glial fibrillar acidic protein, n=2) and neuronal surface (contactin-associated protein-like 2, n=1) specificities. ICIs were withheld and corticosteroid treatment was given in all cases. Five patients received intravenous immunoglobulin, two rituximab, one plasmapheresis and one infliximab. Overall, six patients died. Readministration of ICI was attempted in three patients, without further relapses. Non-small-cell lung cancer was significantly more frequent in patients with CNS-ICI (p<0.01), while melanoma and ipilimumab treatment were more common in PN-ICI (p<0.01 and p=0.01). Conversely, CNS-ICI cases were more frequently antibody-positive than PN-ICI (p<0.01) and showed a strong trend towards poorer outcome (p=0.053). CONCLUSION: Three main clinical phenotypes characterise CNS complications of ICIs, each with distinct immunological background, disease course and response to treatment. Other clinical manifestations (including parkinsonism and steroid-responsive confusion) are also possible. Underlying cancers, antibody prevalence and outcome appear different from those of patients with PN-ICI.

Neurological adverse effects due to programmed death 1 (PD-1) inhibitors.

PURPOSE: PD-1 Immunotherapy is integral in treating multiple cancers, but has been associated with neurological adverse events (nAEs). Our study was aimed at identifying the clinical spectrum of nAEs associated with pembrolizumab and nivolumab. METHODS: We performed an IRB approved single-center retrospective cohort study on patients receiving either pembrolizumab or nivolumab. Patients that developed nAEs within 12 months of treatment were identified. Descriptive statistics were conducted, and differences between groups were analyzed by the Chi-square or t test method. RESULTS: In total, 649 patients were identified. Seventeen patients (2.6%) developed nAEs. Eight of those were on pembrolizumab and nine were on nivolumab. Average age was 62.1 years. Ten were males and 7 were females. Most patients had melanoma (6, 35.3%). Patients who developed nAEs more frequently had intracranial lesions at initiation of anti PD-1 therapy compared to those who did not develop nAEs (76.5% vs 27.8%; p-value < 0.001). Fifteen patients (88.2%) permanently stopped PD-1 therapy. In 8 patients, treatment termination resolved symptoms attributed to immune checkpoint blockade. The majority of patients developed grade 3 or 4 nAEs (10 patients, 58.8%), and required hospitalization (11 patients, 64.7%). Eight patients died for nAEs referable causes. CONCLUSION: Pembrolizumab and nivolumab are associated with the development of nAEs associated with increased risk of permanent discontinuation of treatment, hospitalization, and death. Melanoma patients might be at a particularly high risk of such side effects. Future studies are still required to better assess which patients benefit most from such therapies, while minimizing the risk of complications.

Ramsay-Hunt syndrome and subsequent sensory neuropathy as potential immune-related adverse events of nivolumab: a case report.

BACKGROUND: Nivolumab is an immune checkpoint inhibitor (ICI) and is used for the treatment of advanced non-small cell lung cancer (NSCLC). Several immune-mediated neurological adverse events associated with ICIs have been reported to date, such as Guillain-Barré syndrome. Nivolumab-associated neurological adverse events can vary, and their etiology remains unclear. CASE PRESENTATION: A 72-year-old man with NSCLC was treated with nivolumab as a second-line therapy. After 13 rounds of nivolumab therapy, he presented with Ramsay-Hunt syndrome (RHS) followed by acute ataxic sensory neuropathy. Antiviral therapy for Varicella-Zoster virus and prednisolone resulted in partial improvement of RHS, while almost no recovery was observed in the sensory neuropathy. However, the sensory ataxia significantly improved after intravenous immunoglobulin (IVIg) therapy, and interestingly, the facial palsy associated with RHS also improved. The neurological manifestations, nerve conduction study result, and imaging findings supported that dorsal root ganglia were the primary lesion site of acute ataxic sensory neuropathy. CONCLUSIONS: Our case presented with the comorbidity of RHS and subsequent ataxic sensory neuropathy after nivolumab therapy to whom IVIg was effective. Our case suggested the wide variability of possible neurological symptoms, and the potential usefulness of IVIg to sensory ataxic neuropathy, seen in cancer patients with ICI treatment.

Neurological and related adverse events in immune checkpoint inhibitors: a pharmacovigilance study from the Japanese Adverse Drug Event Report database.

INTRODUCTION: Immune checkpoint inhibitors (ICPI), a breakthrough immunotherapy for cancer, can cause serious neurological adverse events (AEs). We aimed to investigate the characteristics of the neurological and related AEs associated with ICPI treatment, using a large pharmacovigilance database from Japan. METHODS: We conducted disproportionality analysis using the Japanese Adverse Drug Event Report (JADER) database containing 566,698 patient cases recorded between April 2004 and March 2019, to detect neurological and related AE signals associated with ICPI treatment by calculating reporting odds ratio (ROR). RESULTS: Among 7604 cases with ICPI usage, we identified 583 cases (7.67%) with a significantly high reporting of neurological and related AEs (lower 95% of the ROR > 1), including myasthenia gravis (MG), inflammatory myositis, non-infectious encephalitis/myelitis, non-infectious meningitis, hypophysitis/hypopituitarism, and peripheral neuropathy including Guillain-Barre syndrome (GBS). Among the ICPI subtypes, when compared to nivolumab as a reference, number of hypophysitis, hypopituitarism, and meningitis reports from the use of ipilimumab and number of encephalitis/myelitis and meningitis reports from the use of anti-programmed cell death-ligand-1 (PD-L1) agents were significantly higher. Additionally, time to AE onset of symptoms post administration was short in meningitis (median 21 days), MG (median 28 days), myositis (median 28 days), and encephalitis/myelitis (median 32.5 days), while it was longer in peripheral neuropathy (median 42 days), hypophysitis (median 94 days), and hypopituitarism (median 112 days). CONCLUSIONS: Our results showed characteristic features of neurological and related AEs associated with each ICPI subtype, reported in a large number of Japanese patients. This would help in prompt identification and treatment of neurological AEs associated with ICPI treatment.

Neurological Adverse Events Associated with Immune Checkpoint Inhibitors: Diagnosis and Management.

PURPOSE OF REVIEW: Immune checkpoint inhibitors represent a major step forward in the field of oncologic immunotherapy these last years and have significantly increased survival of cancer patients in an ever-growing number of indications. These agents block specific immune checkpoint molecules (programmed cell death protein 1 and its ligand as well as cytotoxic T-lymphocyte-associated antigen 4) that normally downregulate the immune response. These new agents show a specific range of adverse effects induced by abnormal immunologic activation. RECENT FINDINGS: Many different neurologic adverse events have been described, including encephalitis, myelopathy, aseptic meningitis, meningoradiculitis, Guillain-Barré-like syndrome, peripheral neuropathy (including mononeuropathy, mononeuritis multiplex, and polyneuropathy) as well as myasthenic syndrome. Immune checkpoint inhibitors have shown promising results in cancer but can possibly induce autoimmune disorders. Although rare, neurological adverse events require prompt recognition and treatment to avoid substantial morbidity.

Mining of neurological adverse events associated with valbenazine: A post-marketing analysis based on FDA adverse event reporting system.

PURPOSE: Valbenazine is commonly used to treat tardive dyskinesia, and we conducted a pharmacovigilance analysis using the Food and Drug Administration Adverse Event Reporting System (FAERS) to evaluate neurological safety signals associated with valbenazine. METHODS: Data was collected in FAERS from the second quarter of 2017 to the fourth quarter of 2023 for data cleaning. Neurological adverse event (AE) signals of valbenazine were mined by calculating reporting odds ratios (ROR), information component (IC) and empirical Bayesian geometric mean (EBGM). The serious and non-serious cases and signals were prioritized using a rating scale. RESULTS: The number of neurological AE reports where the primary suspect (PS) drug was 8981 for valbenazine. Significant AE signals were identified by the preferred term (PT) analysis for valbenazine, including somnolence (ROR 19.69), tremor (ROR 15.17), and tardive dyskinesia (ROR 236.91), among which 18 AEs were identified as new signals. Patient age (p < 0.009) and sex (p = 0.197) might be associated with an increased risk of neurological AE severity. Notably, the association between valbenazine and neurological disorders remained when stratified by sex, age, and reporter type. AE timing analysis was performed for the drug and four moderate clinical priority signals [i.e., somnolence, balance disorder, parkinsonism, and akathisia (priorities 7)], showing the same early failure type profiles. CONCLUSIONS: The increase in neurological safety signals is identified in the post-marketing research of valbenazine. Clinicians need to pay attention to not only common AEs but also be alert to new neurological AE signals when using valbenazine.

Neurological adverse events associated with oxaliplatin: A pharmacovigilance analysis based on FDA adverse event reporting system.

Objective: This study aimed to explore the neurological adverse events of oxaliplatin through the Food and Drug Administration Adverse Event Reporting System (FAERS) database and to provide reference for safe clinical drug use. Methods: The adverse events report data of oxaliplatin from the first quarter of 2019 (1 January 2019) to the third quarter of 2023 (30 September 2023) were extracted from FAERS database, and the adverse events signal intensity was determined using the reporting odds ratio, proportional reporting ratio, information component, and empirical Bayes geometric mean methods. Time-to-onset and univariate logistic regression analysis were performed to describe the characteristics and risk factors of oxaliplatin-associated neurological adverse events. Results: A total of 4,471 cases of oxaliplatin-associated neurological adverse events were identified, with 318 neurological adverse events being documented, among which 87 adverse events satisfied the thresholds of four methodologies. The median time-to-onset of oxaliplatin-associated neurological adverse events was 2 days (interquartile range 0-36 days). Among the factors significantly influencing oxaliplatin-related neurological adverse events, male sex and combination medication decreased the risk of neurological adverse events, while higher cumulative dose increased the risk. Conclusion: The real-world neurotoxicity spectrum of oxaliplatin and its characteristics and influencing factors were obtained through data mining of FAERS, providing valuable insights for healthcare professionals to effectively manage the risk of neurological adverse events associated with oxaliplatin in clinical practice.

Lung Cancer Wherein Durvalumab Induced Both Anti-CRMP-5 Antibody-related Paraneoplastic Neurological Syndromes and Neurological Adverse Events.

A 68-year-old man with small-cell lung cancer developed anti-collapsin response-mediator protein (CRMP)-5 antibody-related paraneoplastic neurological syndrome (PNS) presenting with ataxia and chorea during treatment with durvalumab. As a result of steroid therapy, anti-CRMP-5 antibodies became negative, hyperintense lesions on brain magnetic resonance imaging disappeared, and neurological symptoms improved. After resuming durvalumab, he became unable to walk due to neurological adverse events (nAEs). There have been no reported cases manifesting PNSs and nAEs as a result of the same immune checkpoint inhibitors (ICIs) administered at different times. Resuming ICIs in patients diagnosed with PNSs should be performed with prudence.

Patterns of neurological adverse events among a retrospective cohort of patients receiving immune checkpoint inhibitors.

Aim: Neurological adverse events (NAEs) are infrequent immune checkpoint inhibitor (ICI) outcomes poorly characterized in extant research, complicating their clinical management. Methods: This study characterized the frequency, severity, patterning and timing of NAEs using a large retrospective registry, including all patients who received at least one dose of an ICI from 2/1/2011-4/7/2022 within our health network. Results: Among 3137 patients, there were 54 NAEs (1.72% any grade; 0.8% grade 3-4). Most NAEs were peripheral (57.4%) versus central (42.6%). Melanoma and renal cell carcinoma were significantly associated with NAEs. Conclusion: The incidence of NAEs was rare though higher than many prior case estimates; the timing was consistent with other AEs. NAEs frequently occurred in tumor types known to favor brain metastases.

Immune checkpoint inhibitors are new drugs for cancer. They boost your body's defenses to fight cancer cells. These drugs can be used alone or with other cancer treatments. Most people are okay with these medicines, but some might have problems in different parts of the body. This can be tricky to figure out. Rarely, there can be issues in the brain or nerves. These side effects are rare, happening in about 2 in every 100 people who use the drugs. They are more common in certain cancers like melanoma and kidney cancer. As doctors learn more about these side effects, they can better predict, treat, and prevent them.

Reactions and adverse events induced by T-cell engagers as anti-cancer immunotherapies, a comprehensive review.

T-cell engagers (TCE) are cancer immunotherapies that have recently demonstrated meaningful benefit for patients with hematological malignancies and solid tumors. The anticipated widespread use of T cell engagers poses implementation challenges and highlights the need for guidance to anticipate, mitigate, and manage adverse events. By mobilizing T-cells directly at the contact of tumor cells, TCE mount an obligatory and immediate anti-tumor immune response that could result in diverse reactions and adverse events. Cytokine release syndrome (CRS) is the most common reaction and is largely confined to the first drug administrations during step-up dosage. Cytokine release syndrome should be distinguished from infusion related reaction by clinical symptoms, timing to occurrence, pathophysiological aspects, and clinical management. Other common reactions and adverse events with TCE are immune effector Cell-Associated Neurotoxicity Syndrome (ICANS), infections, tumor flare reaction and cytopenias. The toxicity profiles of TCE and CAR-T cells have commonalities and distinctions that we sum-up in this review. As compared with CAR-T cells, TCE are responsible for less frequently severe CRS or ICANS. This review recapitulates terminology, pathophysiology, severity grading system and management of reactions and adverse events related to TCE.

Elevated phenylacetic acid levels do not correlate with adverse events in patients with urea cycle disorders or hepatic encephalopathy and can be predicted based on the plasma PAA to PAGN ratio.

BACKGROUND: Phenylacetic acid (PAA) is the active moiety in sodium phenylbutyrate (NaPBA) and glycerol phenylbutyrate (GPB, HPN-100). Both are approved for treatment of urea cycle disorders (UCDs) - rare genetic disorders characterized by hyperammonemia. PAA is conjugated with glutamine in the liver to form phenylacetyleglutamine (PAGN), which is excreted in urine. PAA plasma levels ≥ 500 µg/dL have been reported to be associated with reversible neurological adverse events (AEs) in cancer patients receiving PAA intravenously. Therefore, we have investigated the relationship between PAA levels and neurological AEs in patients treated with these PAA pro-drugs as well as approaches to identifying patients most likely to experience high PAA levels. METHODS: The relationship between nervous system AEs, PAA levels and the ratio of plasma PAA to PAGN were examined in 4683 blood samples taken serially from: [1] healthy adults [2], UCD patients of ≥ 2 months of age, and [3] patients with cirrhosis and hepatic encephalopathy (HE). The plasma ratio of PAA to PAGN was analyzed with respect to its utility in identifying patients at risk of high PAA values. RESULTS: Only 0.2% (11) of 4683 samples exceeded 500 µg/ml. There was no relationship between neurological AEs and PAA levels in UCD or HE patients, but transient AEs including headache and nausea that correlated with PAA levels were observed in healthy adults. Irrespective of population, a curvilinear relationship was observed between PAA levels and the plasma PAA:PAGN ratio, and a ratio>2.5 (both in µg/mL) in a random blood draw identified patients at risk for PAA levels>500 µg/ml. CONCLUSIONS: The presence of a relationship between PAA levels and reversible AEs in healthy adults but not in UCD or HE patients may reflect intrinsic differences among the populations and/or metabolic adaptation with continued dosing. The plasma PAA:PAGN ratio is a functional measure of the rate of PAA metabolism and represents a useful dosing biomarker.

Case report: Cyclosporine A-induced extrapyramidal syndrome following hematopoietic stem cell transplantation.

Introduction: Cyclosporine A-associated neurotoxicity has been reported in up to 40% of patients and its wide range of neurological adverse effects have been reported, ranging from mild tremors to fatal leukoencephalopathy. Extrapyramidal (EP) neurotoxicity is a rare manifestation of cyclosporine. Cyclosporine-induced extrapyramidal syndrome remains a rare adverse reaction. Design/methods: A database search was performed for studies in patients from all age groups. We found a total of 10 articles reporting EP as an adverse effect of cyclosporine A. A total of 16 patients were found, and a thorough review of these patients was performed. A comparison of patients was performed to highlight common clinical presentations, investigations during the symptomatic phase, and prognosis. In addition, we describe an 8-year-old boy who developed cyclosporine-related extrapyramidal signs on day 60 post-hematopoietic stem cell transplantation for beta-thalassemia. Conclusion: Cyclosporine A can induce neurotoxicity resulting in diverse symptoms. Signs of EP are rare manifestations of cyclosporine neurotoxicity and should be considered when evaluating post-transplant recipients of cyclosporine when they are present with any EP symptoms. Discontinuation of cyclosporine results in good recovery in most patients.

NEURO-COVAX: An Italian Population-Based Study of Neurological Complications after COVID-19 Vaccinations.

OBJECTIVE: In this Italian population-based study, we aimed to evaluate the neurological complications after the first and/or second dose of COVID-19 vaccines and factors potentially associated with these adverse effects. METHODS: Our study included adults aged 18 years and older who received two vaccine doses in the vaccination hub of Novegro (Milan, Lombardy) between 7 and 16 July 2021. The NEURO-COVAX questionnaire was able to capture the neurological events, onset and duration. That data that were digitized centrally by the Lombardy region were used to match the demographic/clinical characteristics and identify a vulnerability profile. Associations between vaccine lines and the development of complications were assessed. Digital healthcare system matching was also performed to evaluate severe neurological complications (Guillain-Barrè syndrome, Bell's palsy, transverse myelitis, encephalitis) and the incidence of hospital admissions and/or the mortality rate after two doses of the vaccines. RESULTS: The NEURO-COVAX-cohort included 19.108 vaccinated people: 15.368 with BNT162b2, 2077 with mRNA-1273, 1651 with ChAdOx1nCov-19, and 12 with Ad26.COV2.S who were subsequently excluded. Approximately 31.2% of our sample developed post-vaccination neurological complications, particularly with ChAdOx1nCov-19. A vulnerable clinical profile emerged, where over 40% of the symptomatic people showed comorbidities in their clinical histories. Defining the neurological risk profile, we found an increased risk for ChAdOx1nCov-19 of tremors (vs. BNT162b2, OR: 5.12, 95% CI: 3.51-7.48); insomnia (vs. mRNA-1273, OR: 1.87, 95% CI: 1.02-3.39); muscle spasms (vs. BNT162b2, OR: 1.62, 95% CI: 1.08-2.46); and headaches (vs. BNT162b2, OR: 1.49, 95% CI: 0.96-1.57). For mRNA-1273, there were increased risks of parethesia (vs. ChAdOx1nCov-19, OR: 2.37, 95% CI: 1.48-3.79); vertigo (vs. ChAdOx1nCov-19, OR: 1.68, 95% CI: 1.20-2.35); diplopia (vs. ChAdOx1nCov-19, OR: 1.55, 95% CI: 0.67-3.57); and sleepiness (vs. ChAdOx1nCov-19, OR: 1.28, 95% CI: 0.98-1.67). In the period that ranged from March to August 2021, no one was hospitalized and/or died of severe complications related to COVID-19 vaccinations. DISCUSSION: This study estimates the prevalence and risk for neurological complications potentially associated with COVID-19 vaccines, thus improving the vaccination guidelines and loading in future personalized preventive medicine.

Neurological Adverse Events Associated With Esketamine: A Disproportionality Analysis for Signal Detection Leveraging the FDA Adverse Event Reporting System.

Esketamine was approved for the treatment of treatment-resistant depression in 2019. After the approval of esketamine, numerous concerns have been raised regarding its long-term safety and tolerability. A previous systematic pharmacovigilance study on esketamine-related adverse events (AEs) was published in 2020; however, it has not been updated 2 years later. The primary aim of this study was to detect and characterize neurological safety signals of esketamine to partially update the knowledge in this field using the FDA pharmacovigilance database. Reporting odds ratio (ROR) was calculated for esketamine-related neurological AEs from 2019 to 2021 with a signal considered when the lower limit of the 95% confidence interval (CI) of ROR (ROR025) exceeded one. Severe and non-severe cases were compared using an independent samples t-test or chi-squared (χ2) test, and a rating scale was used to prioritize the signals. The database contained 720 cases of esketamine-associated neurological AEs, with 21 signals detected, ranging from a ROR025 of 1.05 (disturbance in attention) to 204.00 (sedation). 16 latest neurological AEs emerged in the second year of marketing approval of esketamine, with eight signals detected. The associations between esketamine and nervous system disorders persisted when stratifying by sex, age, and reporter type, whereas the spectrum of neurological AEs differed in stratification regimens. Esketamine dosage, antidepressant polypharmacy, or co-prescription with benzodiazepines affected AEs severity (t = 2.41, p = 0.017; χ2 = 6.75, p = 0.009; and χ2 = 4.10, p = 0.043; respectively), while age and sex did not (p = 0.053 and p = 0.397, respectively). Three signals were categorized as moderate clinical priority [i.e., sedation, dizziness, and dysgeusia (priority points 7, 5, and 5, respectively)], showing the same early failure type profiles. Notably, seven detected disproportionality signals were not previously detected in clinical trials. Although the majority of results were in line with those obtained in the previous study, there were discrepancies in the spectrum of neurological AEs and the effects of several risk factors on AEs severity among the two studies that should be recognized and managed early in clinical treatments.

Corrigendum: Neurological adverse events associated with esketamine: A disproportionality analysis for signal detection leveraging the FDA adverse event reporting system.

[This corrects the article DOI: 10.3389/fphar.2022.849758.].

Paraneoplastic Autoimmune Neurological Syndromes and the Role of Immune Checkpoint Inhibitors.

The introduction of immune checkpoint inhibitors (ICIs) in oncologic therapies has led to a paradigm shift in cancer treatment. ICIs have increased the overall survival in patients with malignant melanoma, small-cell lung cancer, and many other tumor entities. Despite their clinical benefits, these novel cancer immunotherapies can induce neurological immune-related adverse events (irAEs). Such immune-mediated complications can manifest within the spectrum of paraneoplastic neurological syndromes (PNSs). PNSs are rare immune-mediated complications of systemic cancers that can involve every aspect of the nervous system. The emergence of PNSs with ICI treatment opens further pathways to study the complex immunopathological interplay of cancer immunity, cross-reactive neurological autoimmune phenomena, and effects of ICIs on the immune system. ICI-induced PNSs comprise a diverse antibody repertoire and phenotypic spectrum with severe and life-threatening disease progression in some cases. Timely diagnosis and urgent interventions are pivotal for a favorable neurologic and oncologic outcome. This review focuses on the pathogenesis of cancer immunotherapy and the disruption of immune tolerance in PNSs and provides an overview of the most pertinent clinical manifestations and principles of diagnostic and therapeutic managements in light of the expected increase in PNSs due to the widespread use of ICIs in clinical practice. This review further discusses potential and evolving concepts of therapeutic monoclonal antibodies for the treatment of PNSs.

Association Between Antipsychotic Treatment and Neurological Adverse Events in Pediatric Patients: A Population-Based Cohort Study in Korea.

Background: Potential adverse effects might be caused by increasing the number of antipsychotic prescriptions. However, the empirical evidence regarding pediatric psychiatric patients is insufficient. Therefore, we explored the antipsychotic-induced adverse effects focusing on the neurological system. Method: Using the medical information of pediatric patients retrieved from the claims data of Health Insurance Review and Assessment in Korea, we identified those psychiatric patients who were started on antipsychotic treatment at age 2-18 years between 2010 and 2018 (n = 10,969). In this study, movement disorders and seizures were considered as major neurological adverse events. The extended Cox model with time-varying covariates was applied to explore the association between antipsychotic medication and adverse events. Findings: Total 1,894 and 1,267 cases of movement disorders and seizures occurred in 32,046 and 33,280 person-years, respectively. The hazard risks of neurological adverse events were 3-8 times higher in the exposed to antipsychotics period than in the non-exposure period. Among the exposure periods, the most dangerous period was within 30 days of cumulative exposure. High doses or polypharmacy of antipsychotics was associated with increased risks of neurological adverse events. Among individual antipsychotics, haloperidol showed the highest risk of developing movement disorders among the examined agents. Quetiapine showed a lower risk of developing movement disorders but a higher risk of developing seizures than risperidone. Conclusion: These findings suggest that antipsychotics should be used with caution in pediatric patients, especially regarding initial exposure, high dose, and polypharmacy.