Neuromyelitis optica spectrum disorder (NMOSD) is a immune-mediated demyelinating disease of the central nervous system, characterized by high recurrence and disability rates. Preventing relapses is crucial in the treatment of this condition. Monoclonal antibodies have emerged as a novel and rapidly evolving clinical therapeutic strategy targeting NMOSD in recent years. An increasing number of studies and clinical trials have also confirmed the effectiveness and safety of monoclonal antibodies. Rituximab, a monoclonal antibody targeting the B-cell surface antigen CD20, has been widely used in the treatment of NMOSD. Currently, in China, the only approved monoclonal antibody for treating NMOSD is Inebilizumab, which targets the B-cell surface antigen CD19. Additionally, various monoclonal antibodies, such as interleukin-6 receptor inhibitors and complement C5 inhibitors, have been used in the treatment of NMOSD. With the deepening of the research on the pathogenesis of NMOSD, the molecular mechanism of disease-related immune network is further clarified, and multi-center clinical trials are widely carried out. More accurate monoclonal antibody treatment strategies for NMOSD will be applied to clinical practice, benefiting more patients.
Neuromyelitis optica spectrum disorders (NMOSD) are a group of inflammatory disorders of the central nervous system characterized by episodes of immune-mediated demyelination and axonal damage mainly involving optic nerves and spinal cord. Neuromyelitis optica related optic neuritis (NMO-ON) is a common neuro-ophthalmic disease which often results in permanent blindness. The discovery of aquaporin 4 antibodies confirms that neuromyelitis optica is a distinct disease entity different from multiple sclerosis. In patients with NMO-ON, the correct therapeutic approach has to recognize two distinct clinical situations: treatment of the acute attacks and prevention of the relapses. With the in-depth study of the pathogenesis of NMOSD, new treatments are emerging in different targets of the disease. This review gives an update of latest treatment of NMO-ON, emphasizing both current situation and future immunotherapy strategies.
Objective To evaluate the efficacy and safety of repeated treatments with low-dose rituximab for relapsing neuromyelitis optica spectrum disorder (NMOSD). Methods A perspective study. 21 patients who were diagnosed with NMOSD one year ago were recruited for rituximab treatment. Of 21 patients, one was male, 20 were females. Onset age was 10 - 51 years, the mean onset age was (26.2±12.0) years. Duration of disease was 2.3 - 25.8 years, the mean duration was (9.2±5.9) years. Best corrected vision activity (BCVA), expanded disability status scale (EDSS), annualized relapsing rate (ARR) were valued to investigate the efficacy and safety of repeated treatments with low-dose rituximab. The BCVA was examined using Snellen chart, and converted to logMAR. The mean BCVA was 1.13±1.09, the mean BCVA in better eyes was 0.4±0.68, the mean BCVA in latter eyes was 1.87±0.90. The mean EDSS was 3.09±0.70. The mean ARR was 1.04±0.65. All patients underwent two cycles of RTX treatment. The annually induction treatment was RTX 100 mg per week for 4 weeks. Of 21 patients, 12 patients had treatment within one month after attack. The mean follow-up period was (28.4±4.9) months. The side effects were recorded, BCVA, EDSS, ARR were valued to investigate the efficacy and safety of repeated treatments with low-dose rituximab. Paired t test, independent sample t test and Chi-squared test were used. Results The mean BCVA at last follow-up was 0.62±0.91, the mean BCVA in better eye was 0.62±0.91, the BCVA in latter eye was 1.0±1.01. The mean EDSS was 2.26±1.07. The mean ARR was 0.21 ± 0.3. After the treatment, patient had significant improvement on BCVA in worst eye (t=4.256), ARR (t=2.900), EDSS (t=4.620) with the significant differences (P＜0.05).Thirteen relapses in 9 patients were observed. B lymph cells were more than 0.01% in all relapses. There was no significant difference on the BCVA in better eye (t=1.840, P＞0.05). There were 9 patients had relapse, 13 times in total. Of 13 relapses, B lymph cell count was performed in 12 relapses, and the counts were 0.01% - 0.14%. There were no significant difference between relapsed patients and non-relapsed patients on onset age (t=0.67, P=0.51), whether underwent plasma exchange treatment (χ2=1.61, P＞0.05), with/without auto-immune antibody ratio (χ2=1.61, P＞0.05). Of 21 patients, 8 patients had side effects, including 5 patients with infection, 4 patients with chest congestion, 3 patients with hair losing, 2 patients with skin rashes, headache and short of breath, 1 patient with tinnitus, palpitation and fatigue. Four patients had more than one symptom. Of all patients who had side effects, slowing down the infusion speed of RTX or infusing 5 mg of dexamethasone could relieve the discomfort. Conclusion Lose-dose rituximab reduces the frequency of NMOSD relapses and is well tolerated.
Plasma exchange (PE) is a therapeutic blood component replacement method. The blood of patients is first separated into plasma and blood cell components using a blood cell separator in vitro, the plasma containing harmful pathogenic substances is then discarded and replaced with the same volume of exchange solution. Finally the separated blood cells together with the exchange solution are returned back to the blood circulation of patients. By reducing the circulating antibodies, abnormal plasma proteins or cytokines and other pathogenic molecules, PE can block the disease process. PE has a good therapeutic effect on neuromyelitis optica-related optic neuritis (NMO-ON), which shows resistant to glucocorticoid therapy for the first onset. The American Society for Apheresis guideline evaluates PE for acute optic neuritis as a recommended grade 1B, type II indication. In the implementation of PE treatment for NMO-ON and other diseases, indications and contraindications should be strictly adhered to the guideline, treatment procedures and protocols should be optimized, common adverse events and its prevention and management should be known and alerted. It is important to conduct multi-center clinical cooperation and a high standard clinical randomized controlled study, to find out the optimal time window, the best protocol, and the associated factors for the efficacy and prognosis of PE in NMO-ON.
ObjectiveTo investigate the alteration of retinal perfusion in aquaporin-4 antibody (AQP4-ab) positive neuromyelitis optica spectrum disorders (NMOSD) patients by optical coherence tomography angiography (OCTA).MethodsA case-control study. Forty-eight AQP4-ab positive NMOSD patients (96 eyes) and 20 age and gender matched healthy controls (40 eyes) were recruited from September 2015 to August 2017 at the Eye & ENT Hospital of Fudan University. Patients of both eyes were included in the groups. The patients were further divided into 4 subgroups (0 ON, 1 ON, 2 ON, 3+ ON group) according to the number of episodes of ON (0, 1, 2, or 3+) with respect to 30、22、31、13 eyes. 0 ON group had no history of ON episodes; 1 ON group, 2 ON group, and 3+ ON group had ON episodes 1, 2, ≥3 times, respectively. All patients underwent complete ophthalmological examinations including BCVA, visual field and OCTA examination. The BCVA was recorded for each eye using metric notation from the Snellen chart, and then converted to the logarithm of the minimum angle of resolution. The central visual field was assessed using a Humphrey Field Analyzer 750 and the mean deviation (MD) was determined. OCTA scans of the optic disc (4.5 mm × 4.5 mm) and macula (6 mm × 6 mm) were acquired. Radial peripapillary capillary (RPC) vessel density, superficial capillary plexus vessel density (SVD), the thickness of ganglion cell and inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) were determined. The generalized estimating equations was performed to compare the difference of BCVA, MD, pRNFL thickness, GCIPL thickness, RPC vessel density and SVD among the groups and the correlations between retinal perfusion and retinal structure, visual function were analyzed. ResultsThe RPC vessel density and SVD were significant lower in the 0 ON group compared with healthy group (Wald χ2=7.190, 10.134; P＜0.01), however, the BCVA, pRNFL and GCIPL thickness were not significant difference between the two groups (Wald χ2=2.308, 1.020, 2.558; P＞0.05). The BCVA, visual field MD, RPC vessel density, SVD, pRNFL and GCIPL were significant lower in 1 ON, 2 ON and 3+ ON groups compared with healthy group and 0 ON group (Wald χ2=12.390, 11.346, 38.860, 18.040, 45.418, 26.608; P＜0.001 ), but the parameters had no significant difference among the three groups (P＞0.05). The RPC vessel density was significantly correlated with pRNFL thickness (β=0.372, standard error=0.018, P＜0.001), and the SVD was significantly correlated with GCIPL thickness (β=0.115, standard error=0.204, P＜0.001). The MD and BCVA was significantly correlated with peripapillary vessel density after adjustment for other variables (BCVA: β=0.025, standard error=0.005, P=0.000; visual field MD: β=0.737, standard error=0.185, P=0.000).ConclusionsSubclinical primary retinal vasculopathy may occur in NMOSD prior to ON attack, the ON attack may further impair visual function, retinal structure and perfusion, however, the extent of injure is not relevant with the increase of ON attack. The peripapillary vessel density might be a sensitive predictor of visual outcomes in NMOSD patients.
Neuromyelitis optica-related optic neuritis (NMO-ON) is a kind of severe optic nerve disease, which always leads to replase, poor prognosis, and even blindness. Aquaporin 4 antibody (AQP4-IgG) is the main diagnostic biomarker for neuromyelitis optica with high specificity. Serum myelin oligodendrocyte glycoprotein antibody (MOG-IgG) is helpful for the diagnosis of AQP4-IgG negative patients. The study of biomarkers is helpful to deeply understand the pathogenesis of NMO-ON, help the diagnosis of the disease, and finally make precise treatment. Orbital MRI can help to differentiate MOG-IgG positive from AQP4-IgG positive neuromyelitis optica and optic neuritis, which is very important for the diagnosis of NMO-ON. At present, the standardized treatment of NMO-ON can be divided into two clinical stages: acute stage and remission stage. Corticosteroids and plasma exchange are the main treatments in acute stage, aiming at alleviating acute inflammatory reaction and improving prognosis. Immunosuppressive agents and biological agents are the main treatments in remission stage, aiming at preventing or reducing recurrence. With the development of the diagnosis and treatment of NMO-ON, we find that it is more and more important to strengthen the construction of neuro-ophthalmology team in China, establish clinical epidemiological database of NMO-ON, and carry out multi-centre, large-sample, prospective clinical control studies in China to provide evidence-based medicine for Chinese people. In addition, we need to strengthen efforts to establish and improve the diagnostic criteria for NMO-ON and the promotion of diagnostic and therapeutic criteria, and strive to improve the clinical diagnosis and treatment level of NMO-ON in China.