Is neuromyelitis optica without AQP4-IgG a T-cell mediated disease? insights from checkpoint inhibitor immune-related adverse events

Predictors of relapse risk and treatment response in AQP4-IgG positive and seronegative NMOSD: A multicentre study

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) can be categorised into aquaporin-4 antibody (AQP4-IgG) NMOSD or seronegative NMOSD. While our knowledge of AQP4-IgG NMOSD has evolved significantly in the past decade, seronegative NMOSD remains less understood. This study aimed to evaluate the predictors of relapses and treatment responses in AQP4-IgG NMOSD and seronegative NMOSD.

METHODS

This was a multicentre, international, retrospective cohort study using the MSBase registry. Recurrent relapse risk was assessed using an Andersen-Gill model and risk of first relapse was evaluated using a Cox proportional hazards model. Covariates that putatively influence relapse risk included demographic factors, clinical characteristics and immunosuppressive therapies; the latter was assessed as a time-varying covariate.

RESULTS

A total of 398 patients (246 AQP4-IgG NMOSD and 152 seronegative NMOSD) were included. The AQP4-IgG NMOSD and seronegative NMOSD patients did not significantly differ by age at disease onset, ethnicity or annualised relapse rate. Both low-efficacy and high-efficacy immunosuppressive therapies were associated with significant reductions in recurrent relapse risk, with notably greater protection conferred by high-efficacy therapies in both AQP4-IgG NMOSD (HR 0.27, 95% CI 0.15 to 0.49, p<0.001) and seronegative NMOSD (HR 0.21, 95% CI 0.08 to 0.51, p<0.001). Longer disease duration (HR 0.97, 95% CI 0.95 to 0.99, p<0.001) and male sex (HR 0.52, 95% CI 0.34 to 0.84, p=0.007) were additional protective variables in reducing the recurrent relapse risk for the AQP4-IgG NMOSD group.

CONCLUSION

Although further studies are needed to improve our understanding of seronegative NMOSD, our findings underscore the importance of aggressive treatment with high-efficacy immunotherapies in both NMOSD subtypes, regardless of serostatus.

Unravelling the Acute, Chronic and Steroid-Refractory Management of High-Grade Neurological Immune-Related Adverse Events: A Call to Action

Rare side effects of immune-checkpoint inhibitors (ICIs) are known as neurological immune-related adverse events (n-irAEs). Typically, n-irAEs affect the peripheral nervous system, primarily presenting as myositis, polyradiculoneuropathy, or cranial neuropathy. Less commonly, they impact the central nervous system, resulting in encephalitis, meningitis, or myelitis. High-grade n-irAEs managing and recognizing remains challenging, considering the risk of mortality and long-term disability. To date, strong scientific data are lacking to support the management of high-grade clinical forms. We performed a systematic literature search, selecting all articles describing high-grade steroid-resistance n-irAEs. and we reported them in a practical review. Specifically, current recommendations advise stopping ICI use and beginning corticosteroid treatment. Our findings highlighted that in steroid-resistant n-irAEs, it should be recommended to quickly escalate to plasma exchange (PLEX) and/or intravenously immunoglobulins (IVIg), usually in association with other immunosuppressants. Furthermore, newer evidence supports the use of drugs that may specifically block inflammation without reducing the anti-tumour effect of ICIs. In this practical review, we provide new evidence regarding the therapeutic approach of high-grade n-irAEs, particularly in steroid-resistant cases. We would also stress the importance of informing the scientific community of the discrepancy between current guidelines and clinical evidence in these rare forms of pathology.

Neuromyelitis optica associated with the use of Atezolizumab in a patient with advanced lung adenocarcinoma

Immune checkpoint inhibitors (ICIs) are a pharmacological group increasingly used in Oncology and Hematology. These treatments can lead to autoimmune complications, with neurological conditions, especially central nervous system (CNS) involvement, being rare. We describe a case of seropositive neuromyelitis optica in a patient with locally advanced lung adenocarcinoma treated with Atezolizumab.

A comprehensive review of the advances in neuromyelitis optica spectrum disorder

Neuromyelitis optica spectrum disorder (NMOSD) is a rare relapsing neuroinflammatory autoimmune astrocytopathy, with a predilection for the optic nerves and spinal cord. Most cases are characterised by aquaporin-4-antibody positivity and have a relapsing disease course, which is associated with accrual of disability. Although the prognosis in NMOSD has improved markedly over the past few years owing to advances in diagnosis and therapeutics, it remains a severe disease. In this article, we review the evolution of our understanding of NMOSD, its pathogenesis, clinical features, disease course, treatment options and associated symptoms. We also address the gaps in knowledge and areas for future research focus.

Immune Checkpoint Inhibitors in Patients with Pre-existing Neurologic Autoimmune Disorders

PURPOSE OF REVIEW

The use of immune checkpoint inhibitors (ICIs) for oncologic indications is associated with immune-related adverse events (irAEs). Patients with pre-existing autoimmune diseases are at increased risk of irAEs and have largely been excluded from clinical trials of ICIs. Therefore, there is limited data on the safety of safety of ICIs in patients with pre-existing neurologic autoimmune diseases (nAIDs) such as myasthenia gravis and multiple sclerosis. This review aims to synthesize the literature on the post-marketing experience with ICI in patients with pre-existing nAID and to discuss possible strategies for mitigating the risk of post-ICI nAID relapses.

RECENT FINDINGS

Patients with pre-existing myasthenia gravis (MG), myositis, and paraneoplastic encephalitis appear highly susceptible to neurologic relapses of their underlying neurologic disorder following ICI initiation; these relapses can cause considerable morbidity and mortality. In patients with multiple sclerosis (MS), the risk and severity of MS relapses following ICI appears to be relatively lower compared to MG. Preliminary evidence suggests that older MS patients with no recent focal neuroinflammatory activity may be safely treated with ICI. Among the several case reports of ICI in patients with a history of Guillain-Barre syndrome (GBS), neurologic worsening was only recorded in one patient who was in the acute phase of GBS at the time of ICI start. Initiating an ICI in a patient with pre-existing nAID involves a complex risk-benefit discussion between the patient, their oncologist, and neurologist. Relevant issues to consider before ICI include the choice of disease-modifying therapy for nAID (if any) and strategies for promptly identifying and managing nAID relapses should they occur. Currently, the literature consists mainly of case reports and case series, subject to publication bias. Prospective studies of ICI in patients with nAID are needed to improve the level of evidence.

Recurrent Optic Neuritis and Perineuritis Followed by an Unexpected Discovery

We describe a woman with a history of relapsing acute optic neuritis and perineuritis. Testing failed to confirm a specific diagnosis; hence, she was diagnosed with seronegative neuromyelitis optica spectrum disorder and treated with the immunotherapy rituximab, later in conjunction with mycophenolate mofetil. She achieved a durable remission for 9 years until she presented with paresthesia affecting her left fifth digit, right proximal thigh, and left foot, while also reporting a 25-pound weight loss over the prior 3 months. New imaging demonstrated a longitudinally extensive and enhancing optic nerve, in conjunction with multifocal enhancing lesions within the spinal cord, in a skip-like distribution. The differential diagnosis is discussed.

A case report of neuromyelitis optica spectrum disorder induced by pembrolizumab treatment for lung adenocarcinoma: a clinical and immunohistochemical study

BACKGROUND

We report a case of neuromyelitis optica spectrum disorders (NMOSD), who developed after the pembrolizumab treatment, an immune checkpoint inhibitor, against lung adenocarcinoma. The present case is discussed with the lung adenocarcinoma specimen which was stained by aquaporin-4 (AQP4) and with literature review of NMOSD linked to immune checkpoint inhibitors.

CASE PRESENTATION

A 62-year-old Japanese man presented with acute diencephalic syndrome, left optic neuritis, and myelitis 5 months after initiation of pembrolizumab treatment for lung adenocarcinoma. He was diagnosed with NMOSD based on serum anti-aquaporin-4 (AQP4) antibody positivity. Immunohistochemistry of lung biopsy samples showed AQP4 expression on CD68+ cells. This is the fifth reported case of AQP4+ NMOSD triggered by an immune checkpoint inhibitor and the first with a brain lesion. Four out of five NMOSD cases, including the present case and one case with lung metastasis, had lung cancer.

CONCLUSIONS

Immune checkpoint inhibitors may trigger AQP4+ NMOSD owing to their molecular similarity to AQP4 expressed in lung and glial tissues. Prompt brain/spinal cord imaging and anti-AQP4 antibody testing may facilitate early diagnosis of immune-mediated adverse event in central nervous system associated with immune checkpoint inhibitors.

Systematic identification of the interventional mechanism of Qingfei Xiaoyan Wan (QFXYW) in treatment of the cytokine storm in acute lung injury using transcriptomics-based system pharmacological analyses

CONTEXT

Acute lung injury (ALI) is a complex, severe inflammation disease with high mortality, and there is no specific and effective treatment for ALI. Qingfei Xiaoyan Wan (QFXYW) has been widely used to treat lung-related diseases for centuries.

OBJECTIVE

This study evaluates the potential effects and elucidates the therapeutic mechanism of QFXYW against LPS induced ALI in mice.

MATERIALS AND METHODS

BALB/c Mice in each group were first orally administered medicines (0.9% saline solution for the control group, 0.5 mg/kg Dexamethasone, or 1.3, 2.6, 5.2 g/kg QFXYW), after 4 h, the groups were injected LPS (1.0 mg/kg) to induce ALI, then the same medicines were administered repeatedly. The transcriptomics-based system pharmacological analyses were applied to screen the hub genes, RT-PCR, ELISA, and protein array assay was applied to verify the predicted hub genes and key pathways.

RESULTS

QFXYW significantly decreased the number of leukocytes from (6.34 ± 0.51) × 10⁵/mL to (4.01 ± 0.11) × 10⁵/mL, accompanied by the neutrophil from (1.41 ± 0.19) × 10⁵/mL to (0.77 ± 0.10) × 10⁵/mL in bronchoalveolar lavage fluid (BALF). Based on Degree of node connection (Degree) and BottleNeck (BN), important parameters of network topology, the protein-protein interaction (PPI) network screened hub genes, including IL-6, TNF-α, CCL2, TLR2, CXCL1, and MMP-9. The results of RT-PCR, ELISA, and protein chip assay revealed that QFXYW could effectively inhibit ALI via multiple key targets and the cytokine-cytokine signalling pathway.

CONCLUSIONS

This study showed that QFXYW decreased the number of leukocytes and neutrophils by attenuating inflammatory response, which provides an important basis for the use of QFXYW in the treatment of ALI.

Prevalence of iatrogenic CNS inflammation at a tertiary neuroimmunology clinic

BACKGROUND

Various vaccines, tumor-necrosis-factor-alpha inhibitors (TNFAIs), immune-checkpoint inhibitors (ICIs), and other immunomodulators have been linked to inflammatory CNS events. The prevalence of iatrogenic events in the neuroimmunology clinic is unknown.

OBJECTIVE

To evaluate the prevalence and clinical characteristics of iatrogenic CNS inflammation in a tertiary neuroimmunology clinic.

METHODS

We analyzed 422 consecutive patients seen over five years at a tertiary neuroimmunology clinic who were systematically screened for exposure to vaccines, TNFAIs, ICIs, or other immunomodulators. In patients with suspected iatrogenic events, the Naranjo Adverse Drug Reaction Probability Scale was used to score the probability of iatrogenicity.

RESULTS

In total, 27 potential iatrogenic events were observed, accounting for 6.4% of all new referrals. The average Naranjo score was 5.78 +/- 1.65 with 74% of the cases scored as probable and 26% scored as possible. The clinical phenotypes included MS relapses (37%); autoimmune encephalitis (30%); NMOSD attacks (15%); transverse myelitis (11%); optic neuritis (4%); and MOGAD attacks (4%). A monophasic course was observed in 44% of cases while 41% had a relapsing course. All patients stopped or interrupted treatment with the offending agent. In addition, 41% of the iatrogenic events were fully responsive to corticosteroids; 22% were partially responsive; and 15% resolved spontaneously. The most common potential triggers were vaccines (37%) followed by TNFAIs (33%) then ICIs (26%). A significantly higher number of probable iatrogenic events were observed among the ICI and vaccine groups compared to a higher number of possible events among the TNFAI group. The latter group also had a significantly longer interval since exposure. The ICI group was more likely to present with monophasic autoimmune encephalitis.

CONCLUSION

Iatrogenic CNS inflammation is rare and typically involves steroid-responsive monophasic events. A subset of iatrogenic events can unmask or worsen relapsing disorders. The probability of iatrogenicity was higher in vaccine and ICI-related events compared to TNFAI-related events.

Plasma Exchange for Severe Immune-Related Adverse Events from Checkpoint Inhibitors: An Early Window of Opportunity?

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of several advanced malignancies leading to durable remission in a subset of patients. Their rapidly expanding use has led to an increased frequency of immune-related adverse events (irAEs). The pathogenesis of irAEs is poorly understood but may involve aberrant activation of T cells leading to inflammatory cytokine release or production of pathogenic antibodies leading to organ damage. Severe irAEs can be extremely debilitating and, in some cases, life threatening. IrAEs may not always be corticosteroid responsive or may require excessively high, often toxic, corticosteroid doses. Therapeutic plasma exchange (PLEX) is a treatment modality that has shown promising results for the management of certain severe irAEs, including irAEs that are not mentioned in current treatment guidelines. PLEX may attenuate ongoing irAEs and prevent delayed irAEs by accelerating clearance of the ICI, or by acutely removing pathogenic antibodies, cytokines, and chemokines. Here, we summarize examples from the literature in which PLEX was successfully used for the treatment of irAEs. We posit that timing may be a critical factor and that earlier utilization of PLEX for life-threatening irAEs may result in more favorable outcomes. In individuals at high risk for irAEs, the availability of PLEX as a potential therapeutic mitigation strategy may encourage life-saving ICI use or rechallenge. Future research will be critical to better define which indications are most amenable to PLEX, particularly to establish the optimal place in the sequence of irAE therapies and to assess the ramifications of ICI removal on cancer outcomes.

Uncommon inflammatory/immune-related myelopathies

The differential diagnosis for immune-mediated myelopathies is broad. Although clinical manifestations overlap, certain presentations are suggestive of a particular myelopathy etiology. Spine MRI lesion characteristics including the length and location, and the pattern of gadolinium enhancement, help narrow the differential diagnosis and exclude an extrinsic compressive cause. The discovery of specific antibodies that serve as biomarkers of myelitis such as aquaporin-4-IgG and myelin-oligodendrocyte -glycoprotein-IgG (MOG-IgG), has improved our understanding of myelitis pathophysiology and facilitated diagnosis. In this review we will focus on the pathophysiology, clinical presentation, imaging findings and treatment and outcomes of uncommon immune-mediated myelopathies.

Paraneoplastic Neurological Syndromes and Beyond Emerging With the Introduction of Immune Checkpoint Inhibitor Cancer Immunotherapy

Paraneoplastic neurological syndromes are more commonly seen with malignancies such as small cell lung cancer, thymoma, gynecological malignancies, and breast cancer as well as seminoma. With the introduction of immune checkpoint inhibitor (ICI) cancer immunotherapy we see an increase of autoimmune neurological complications in patients with malignancies not traditionally associated with paraneoplastic neurological syndromes, such as melanoma and renal cell carcinoma. Immune checkpoint inhibitors enhance antitumor immune responses resulting often in immune-related adverse effects that can affect any organ, including the central and peripheral nervous system, neuromuscular junction and muscle. Neurological complications are rare; neuromuscular complications are more common than central nervous system ones but multifocal neurological presentations are often encountered. The vast majority of neurological complications appear within 3 months of ICI initiation, but have been described even after ICI cessation. Neural autoantibody testing reveals autoantibodies in approximately half of the patients with CNS complications. Early suspicion and diagnosis is critical to avoid worsening and improve outcomes. Therapeutic strategies depend on the severity of the symptoms and initially typically involve discontinuation of ICI and high dose steroids. Further immunosuppression might be necessary. Outcomes are dependent on patient's characteristics and clinical presentations.