Questioning the existence of monophasic neuromyelitis optica spectrum disorder by defining a novel long-term relapse-free form from a large Chinese population

FCGR3A-V158F gene polymorphism: A potential predictor for rituximab dosing optimization in Chinese patients with neuromyelitis optica spectrum disorder

BACKGROUND

Rituximab (RTX), an anti-CD20 monoclonal antibody, has shown promise in managing neuromyelitis optica spectrum disorders (NMOSD) by depleting B cells and reducing relapses. However, there is no consensus on the optimal RTX dosing regimen, and genetic factors, such as FCGR3A-V158F polymorphism, may influence treatment outcomes. This study investigates how FCGR3A-V158F genotypes influence RTX efficacy in Chinese NMOSD patients under varying dosing regimens and aims to optimize treatment protocols.

METHODS

We conducted a retrospective analysis of 25 Chinese NMOSD patients treated with RTX, grouped into standardized and low-dosage regimens. FCGR3A-V158F genotypes were determined, and treatment responses were evaluated, including relapse rates, time to first relapse (TFR), B-cell depletion, dose adjustments, and treatment retention.

RESULTS

Among all patients, 15 received standardized dosages, while 10 received varied induction doses (500 mg to 1200 mg) in low-dose regimens. For FCGR3A-V158F genotypes, 15 had the FF genotype, and 10 were V carriers (3 VV genotype, 7 VF genotype). Regardless of dosing, FF genotype patients had a higher relapse rate post-RTX treatment compared to V carriers (P < 0.05). None of the 3 VV genotype patients in either dose group experienced relapses post-RTX. In both dose groups, FF genotype patients had significantly shorter TFR and required more RTX dose adjustments post-RTX treatment compared to V carriers in the standardized dosage group (P < 0.05). FF genotype patients in the low dosage group were more likely to experience insufficient B-cell depletion, had lower treatment retention rates, and more discontinuations than V carriers in the standardized dosage group (P < 0.05). Insufficient B-cell depletion significantly predicted clinical relapses after RTX treatment (P < 0.05). In survival analysis, FF genotype patients, regardless of dosing, experienced earlier relapses post-RTX treatment (P < 0.05).

CONCLUSIONS

This study highlights the importance of RTX dosage selection in NMOSD treatment, particularly for FCGR3A-FF genotype patients. Standard-dose RTX therapy with vigilant monitoring of peripheral blood B-cell levels is recommended for these individuals to optimize treatment efficacy.

Asymptomatic spinal lesions in patients with AQP4-IgG-positive NMOSD: A real-world cohort study

OBJECTIVE

This study aims to explore the frequency and influencing factors of asymptomatic spinal lesions (ASLs) and their impact on subsequent relapses in patients with AQP4-IgG-positive NMOSD (AQP4-NMOSD) in a real-world setting.

METHODS

We retrospectively reviewed clinical information and spinal MRI data from AQP4-NMOSD patients who had at least one spinal cord MRI during their follow-ups. Kaplan-Meier curves and Cox proportional hazards models were employed to ascertain potential predictors of remission ASLs and to investigate factors associated with subsequent relapses.

RESULTS

In this study, we included 129 patients with AQP4-NMOSD and reviewed 173 spinal MRIs during attacks and 89 spinal MRIs during remission. Among these, 6 ASLs (3.5%) were identified during acute attacks, while 8 ASLs (9%) were found during remission. Remission ASLs were linked to the use of immunosuppressive agents, particularly conventional ones, whereas no patients using rituximab developed ASLs (p = 0.005). Kaplan-Meier curve analysis indicated that patients with ASLs had a significantly higher relapse risk (HR = 4.658, 95% CI: 1.519-14.285, p = 0.007) compared to those without. Additionally, the use of mycophenolate mofetil (HR = 0.027, 95% CI: 0.003-0.260, p = 0.002) and rituximab (HR = 0.035, 95% CI: 0.006-0.203, p < 0.001) significantly reduced the relapse risk. However, after accounting for other factors, the presence of ASLs did not exhibit a significant impact on subsequent relapses (HR = 2.297, 95% CI: 0.652-8.085, p = 0.195).

INTERPRETATION

ASLs may be observed in patients with AQP4-NMOSD. The presence of ASLs may signify an underlying inflammatory activity due to insufficient immunotherapy. The administration of immunosuppressive agents plays a key role in the presence of remission ASLs and the likelihood of subsequent relapses.

Overlap syndrome of anti-aquaporin-4 positive neuromyelitis optica spectrum disorder and systemic lupus erythematosus: A systematic review of individual patient data

BACKGROUND

Neurological involvement can occur in systemic lupus erythematosus (SLE) due to co-existing neuromyelitis optica spectrum disorder (NMOSD). The symptoms can mimic those of neuropsychiatric manifestations of SLE. Pathogenic anti-aquaporin-4 (AQP4) antibodies, commonly found in NMOSD, are responsible for the neuroinflammatory response and secondary demyelinating lesions. These anti-AQP4 antibodies can be the drivers of neuroinflammatory process in SLE patients, which is distinct from the immunopathogenesis seen in traditional neuropsychiatric SLE. The clinical course is often a relapsing one and is managed differently. In this review, we describe and outline the clinical course and outcomes of AQP4+ NMOSD/SLE overlap cases.

METHODS

To investigate the co-existence of SLE with AQP4+NMOSD, we conducted a systematic review of individual patient data from case reports and case series reported in major databases. The study extracted clinic-demographic features, imaging and laboratory profiles, treatment approaches, and outcomes of these patients. Inclusion criteria for the review required patients to have positivity for AQP4 or NMO in the blood and/or cerebrospinal fluid (CSF) and exhibit at least one manifestation of both NMOSD and SLE.

RESULTS

In this overlap between SLE and AQP4+NMOSD, a high female preponderance was observed, with 42 out of 46 patients (91.3%) being female. Nearly half of the NMOSD cases (47.8%) had onset after lupus, with a median of 5 years between the two diagnoses. Hematological manifestations were seen in the majority of patients (63%), as well as longitudinally extensive transverse myelitis (87%), and brainstem involvement on imaging (29.6%). Cerebrospinal fluid analysis showed a dominantly lymphocytic pleocytosis, with oligoclonal bands being reported scarcely. Although cyclophosphamide was the most common steroid sparing agent used for maintenance, robust evidence for both efficacy and safety in AQP4+NMOSD is available for mycophenolate mofetil, azathioprine, and rituximab. The majority of reported cases showed a relapsing course, while one patient had a monophasic course.

CONCLUSION

AQP4+NMOSD in SLE patients is a relapsing and neurologically disabling disorder that can mimic neuropsychiatric manifestations, frequently occurs after the onset of lupus or may predate, responds to immunosuppressants, and necessitates indefinite treatment.

Overlap syndrome of anti-aquaporin 4 positive neuromyelitis optica spectrum disorder and primary Sjögren's syndrome: a systematic review of individual patient data

Central nervous system (CNS) involvement can occur in primary Sjögren's syndrome (pSS) due to co-existing neuromyelitis optica spectrum disorder (NMOSD) which has a highly relapsing course requiring indefinite immunosuppression, and if not diagnosed early, damage accrual occurs over time leading to permanent disability and morbidity. In this review, we describe and outline the clinical course and outcomes of anti-aquaporin 4 (AQP4) antibody seropositive NMOSD with pSS overlap cases. To investigate the co-existence of AQP4 + NMOSD with pSS, we conducted a review of individual patient data from case reports and case series found in major databases. The study extracted clinico-demographic features, imaging and laboratory profiles, treatment approaches, and outcomes of these patients. Inclusion criteria for the review required patients to have positivity for anti-AQP4 or NMO-IgG autoantibodies in the blood and/or cerebrospinal fluid (CSF) and exhibit at least one manifestation of both pSS and NMOSD. In this overlap between AQP4 + NMOSD and pSS, 44 patients were included of whom 41 (93.2%) were females. The mean age of pSS onset was 44.8 ± 18.4 years and NMOSD onset was 43.2 ± 19.8 years. In 20 (45.5%) patients, NMOSD preceded pSS onset, 13 (29.5%) NMOSD occurred after pSS onset, and 11 (25%) patients had a simultaneous presentation. 31 (70.5%) patients experienced acute transverse myelitis, 21 (47.7%) optic neuritis, 14 (31.8%) cerebral syndrome, 10 (22.7%) acute brainstem syndrome, 5 (11.4%) area postrema syndrome, and 2 (4.5%) diencephalic clinical syndromes. For the treatment of acute phase, 40 (90.9%) patients received intravenous methylprednisolone, 15 (34.1%) received plasma exchange, and 10 (22.7%) received intravenous immunoglobulin; and for the induction/maintenance therapy, 16 (36.4%) patients received cyclophosphamide, 6 (13.6%) received rituximab, 16 (36.4%) received azathioprine, and 10 (22.7%) received mycophenolate mofetil. Disease course was monophasic in 2 (4.5%) and relapsing in 27 (61.4%) patients. At median (IQR) follow-up duration of 2.4 (6) years, 39 (88.6%) patients showed improvement, 3 (6.8%) showed stabilization and 2 (4.5%) showed worsening of their NMOSD manifestations. In this overlap syndrome of AQP4 + NMOSD and pSS, patients have a neurologically disabling disorder that can mimic neurological manifestations of pSS, frequently occurs prior to the onset of pSS, has a relapsing course, responds well to immunosuppressants, and necessitates indefinite treatment. Collaborative multicentre studies are needed to clarify the natural history and outcomes of this rare overlap syndrome.

Aquaporin-4 Antibody Dynamics and Relapse Risk in Seropositive Neuromyelitis Optica Spectrum Disorder Treated with Immunosuppressants

OBJECTIVE

To investigate aquaporin-4 antibody (AQP4-IgG) dynamics and relapse risk in patients with seropositive neuromyelitis optica spectrum disorder treated with immunosuppressants.

METHODS

This observational cohort study with prospectively collected data included 400 neuromyelitis optica spectrum disorder patients seropositive for AQP4-IgG and treated with immunosuppressants. Serum AQP4-IgG was detected by fixed cell-based assay every 6 months.

RESULTS

After treatment with immunosuppressants, 128 patients became AQP4-IgG seronegative. The median time to become seronegative for 400 patients was 76.4 months (61.4 months, NA). Among those patients with negative change of AQP4-IgG, the mean annualized relapse rate significantly decreased after patients became seronegative (0.20 vs 0.77, p < 0.001), and a positive correlation was observed between time to become seronegative and relapse (OR 1.018, 95% CI 1.001-1.035, p < 0.05). Independent risk factors for AQP4-IgG becoming seronegative were older age at onset, initiation of immunosuppressants at onset, and shorter disease duration before maintenance therapy. Independent risk factors for relapse included younger age (≤46.4 years) at onset, poly-system involvement in the first attack, and unchanged or increased AQP4-IgG titer. The relapse risk was not associated with sex, combination with connective tissue disease, seropositivity for systemic autoimmune antibodies, or incomplete recovery from the first attack.

INTERPRETATION

Patients with younger age at onset, poly-system involvement in the first attack, and unchanged or increased titer of AQP4-IgG are most likely to experience relapse under treatment with immunosuppressants. Time to AQP4-IgG becoming seronegative and change of AQP4-IgG titer may become the surrogate efficacy biomarkers in clinical trials. ANN NEUROL 2023.

Current view on the diagnosis and treatment of neuromyelitis optica spectrum disorders exacerbations

Irreversible neurological deficit and disability in neuromyelitis optica spectrum disorders (NOSD) are formed as a result of exacerbations, which are often life-threatening. Timely diagnosis and treatment of exacerbations is a key task in the management of this category of patients. A unified structured approach to the diagnosis and treatment of NOSD exacerbations has not been developed. The purpose of this article is to analyze the scientific literature data on this issue in order to optimize the diagnostics and treatment of NOSD exacerbations in everyday clinical practice. 

Treatment response, risk of relapse and clinical characteristics of Taiwanese patients with neuromyelitis optica spectrum disorder

BACKGROUND/PURPOSE

The long-term disease course and efficacy of maintenance therapies have rarely been investigated in Asian patients with neuromyelitis optica spectrum disorder (NMOSD).

METHODS

Medical records of patients fulfilling the 2015 International Consensus Diagnostic Criteria for NMOSD at three medical centers in Taiwan were systematically analyzed. Linear regression analysis was performed to investigate factors related to annualized relapse rate (ARR); survival analysis was used to estimate the relapse-free intervals among therapies.

RESULTS

A total of 557 relapses affecting 648 regions (202 optic neuritis, 352 acute myelitis, and 94 brain syndromes) in 204 patients were analyzed during a follow-up period of 69.5 months (range, 1-420). Up to 36.1% of myelitis-onset patients and 24.0% of optic neuritis-onset patients exhibited a limited form disease, defined as having one or more relapses confined to the same region. The median ARR was significantly lower in patients with limited form disease than those with relapses involving multiple regions (0.30 vs. 0.47, respectively). An older age at disease onset was associated with a lower ARR (p = 0.023). Kaplan-Meier analysis showed that the estimated time (months) to next relapse was longest in rituximab-treatment group (58.0 ± 13.2), followed by immunosuppressant (48.5 ± 4.8) or prednisone (29.6 ± 4.6) groups, and shortest in those without maintenance therapy (27.6 ± 4.2) (p = 8.1 × 10^-7).

CONCLUSION

Limited form disease and older age at disease onset are associated with a lower relapse rate in NMOSD. Compared to no maintenance therapy, rituximab and immunosuppressant significantly reduce the relapse risks.

Evidence for and against subclinical disease activity and progressive disease in MOG antibody disease and neuromyelitis optica spectrum disorder

Myelin oligodendrocyte glycoprotein antibody disease (MOGAD) and aquaporin-4 IgG seropositive neuromyelitis optica spectrum disorder (AQP4-IgG+ NMOSD) are generally considered to be relapsing disorders, without clinical progression or subclinical disease activity outside of clinical relapses, in contrast to multiple sclerosis (MS). With advances in the diagnosis and treatment of these conditions, prolonged periods of remission without relapses can be achieved, and the question of whether progressive disease courses can occur has re-emerged. In this review, we focus on studies exploring evidence for and against relapse-independent clinical progression and/or subclinical disease activity in patients with MOGAD and AQP4-IgG+ NMOSD.

Efficacy and safety of modified reduced-dose rituximab in Chinese patients with neuromyelitis optica spectrum disorder: A retrospective cohort study

OBJECTIVE

To evaluate the long-term efficacy and safety of a modified reduced-dose rituximab (mRTX) regimen compared with azathioprine (AZA) and mycophenolate mofetil (MMF) in Chinese patients with neuromyelitis optica spectrum disorder (NMOSD).

METHODS

In this retrospective cohort study, 71 patients with NMOSD were treated with AZA (n = 24), MMF (n = 18), or mRTX (n = 29). The primary outcome was initial relapse after first-line immunosuppressant therapy. The annualized relapse rate (ARR), expanded disability status scale (EDSS) score, activities of daily living (ADL) scale score, and treatment-related adverse events were compared between groups.

RESULTS

Significant ARR reductions were observed in the three groups, with relapse-free rates of 37.5%, 72.2%, and 79.3% in the AZA, MMF, and RTX groups, respectively. Compared with AZA, mRTX and MMF significantly reduced the NMOSD relapse risk. Relapse within 1 year before immunosuppressant therapy or ARR before immunosuppressant therapy increased the NMOSD relapse risk. mRTX and MMF were superior to AZA in reducing the EDSS score and increasing the ADL score, but there was no significant difference between the mRTX and MMF groups. Additionally, mRTX-treated patients were less likely to use steroids concurrently than those treated with AZA and MMF. The adverse event rate in the AZA group was relatively higher than that in the MMF and mRTX groups, though no significant difference was noted among the three groups.

CONCLUSIONS

Compared with AZA, mRTX and MMF significantly reduced the NMOSD relapse risk. mRTX-treated patients presented less concomitant steroid use than those treated with AZA and MMF, fewer adverse events, and better tolerance.

Optic neuritis classification in 2021

Optic neuritis (ON) can be associated with inflammatory disease of the central nervous system or can be isolated, with or without relapse. It can also be associated with infectious or systemic disease. These multiple associations based on a variety of clinical, radiological, and biological criteria that have changed over time have led to overlapping phenotypes: a single ON case can be classified in several ways simultaneously or over time. As early, intensive treatment is often required, its diagnosis should be rapid and precise. In this review, we present the current state of knowledge about diagnostic criteria for ON aetiologies in adults and children, we discuss overlapping phenotypes, and we propose a homogeneous classification scheme. Even if distinctions between typical and atypical ON are relevant, their phenotypes are largely overlapping, and clinical criteria are neither sensitive enough, nor specific enough, to assure a diagnosis. For initial cases of ON, clinicians should perform contrast enhanced MRI of the brain and orbits, cerebral spinal fluid analysis, and biological analyses to exclude secondary infectious or inflammatory ON. Systematic screening for MOG-IgG and AQP4-IgG IgG is recommended in children but is still a matter of debate in adults. Early recognition of neuromyelitis optica spectrum disorder, MOG-IgG-associated disorder, and chronic relapsing idiopathic optic neuritis is required, as these diagnoses require therapies for relapse prevention that are different from those used to treat multiple sclerosis.

Risk of relapse in patients with neuromyelitis optica spectrum disorder: Recognition and preventive strategy

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune inflammatory disorder of the central nervous system (CNS) that is mainly associated with serum autoantibodies against aquaporin-4 (AQP4) in astrocytes. The relapsing clinical course of NMOSD, which can be blinding and disabling due to severe visual impairment, spinal cord lesions and a group of brain syndromes, suggests the importance of accurately evaluating the likelihood and severity of relapse at an early stage of the disease. To date, many risk factors have been revealed in association with relapse, and only some of them are supported by substantial evidence. Furthermore, while the clinical use of conventional immunosuppressants is mostly empirical, an increasing number of emerging therapies for monoclonal antibodies have been confirmed by several randomized placebo-controlled trials to be effective and safe for relapse prevention. In this review, we summarize the reported risk factors that may influence the frequency, symptoms, severity and prognosis of relapse in NMOSD, as well as the efficacy and safety of emerging therapies for relapse prevention. All of these results enable us to better recognize patients who are at higher risk of relapse and suggest more effective monoclonal antibody therapies for use in these patients.

NMOSD acute attack: Understanding, treatment and innovative treatment prospect

Neuromyelitis optica spectrum disorder (NMOSD) is a group of severe inflammatory demyelinating disorders of the central nervous system that involves the optic nerve and spinal cord. Currently the therapeutic options for an acute attack in NMOSD are limited and rarely characterized in clinical studies. This review discussed the overall characteristics of acute attack of NMOSD, related risk factor, prognosis and management. Considering the huge unmet needs and the emergence of new therapeutic targets, we also reviewed innovative treatments that might alleviate attack damage, along with the challenges to evaluate new drug for acute attack in NMOSD.