Efficacy of Low-Dose Rituximab on Neuromyelitis Optica-Associated Optic Neuritis

Nomogram for the prediction of relapse factors in patients with neuromyelitis optica spectrum disorder during rituximab treatment

OBJECTIVES

Develop a nomogram to analyse the factors influencing the relapse of neuromyelitis optica spectrum disorder (NMOSD) during rituximab (RTX) treatment.

METHODS

A retrospective analysis of 214 NMOSD patients identified 181 with AQP4-IgG-seropositive. 32 patients who relapsed during RTX treatment were included, and 122 sets of lymphocyte subset monitoring data were collected. 110 sets of data were finally included and divided into relapse (n = 30) and nonrelapse (n = 80) groups depending on whether a relapse occurred between two adjacent RTX treatments. Logistic and LASSO regressions were used to identify the relevant factors influencing NMOSD relapse, and a nomogram was constructed. Receiver operating characteristic (ROC) curves were generated to evaluate the nomogram's ability to differentiate, and the bootstrap method was utilized for internal validation. Calibration curve and decision curve analysis were also conducted.

RESULTS

Comparing baseline data revealed differences in the RTX administration interval, CD3-CD19+ B lymphocyte and CD3-CD56+ NK cell levels. The RTX administration interval and the level of CD3-CD19+ B lymphocytes were independent variables influencing relapse. The nomogram had an area under the curve (AUC) of 0.71 and a 95% confidence interval (CI) of 0.58-0.83. The Hosmer-Lemeshow (H-L) goodness-of-fit test yielded a χ2 = 11.80 (p = 0.16). Decision curve analysis revealed that the model provided greater net benefits within the threshold probability range of 0.18-0.98.

CONCLUSION

The nomogram developed in this study showed that the RTX administration interval and CD3-CD19+ B lymphocyte levels independently influence NMOSD relapse, indicating good discriminative ability, consistency, and clinical benefits.

A real-world study on the utility of regular rituximab treatment for neuromyelitis optica spectrum disorder

Rituximab (RTX) is a monoclonal antibody targeting the B-cell CD20 surface antigen used as a prophylactic treatment for Aquaporin 4-immunoglobulin G (AQP4-IgG)-positive neuromyelitis optica spectrum disorder (NMOSD). However, a consensus regarding dosage and maintenance intervals is lacking, and the effects of regular/irregular use on disease recurrence and prognosis, and the risk factors associated with clinical relapse, remain unclear. Therefore, we investigated the efficacy/safety of regular RTX use in patients with NMOSD, and explored risk factors associated with clinical relapses. Data from 106 patients with NMOSD were retrospectively collected from January 5, 2016, and March 1, 2023. Patients were categorized as regular/irregular RTX use, with the latter defined by two intervals of > 9 months, or a single interval of > 12 months, without B-cell monitoring. Compared to the regular treatment group, irregular treatment group showed significant higher annual recurrence rate (ARR) (p = 0.033), Expanded Disability Status Scale (EDSS) score (p = 0.041), and proportions of severe relapse (p = 0.006). In regular RTX use group, the cumulative relapse risk after RTX treatment was significantly lower (p < 0.001). When only considering relapses occurring more than 1 month after starting RTX treatment, 82.3% (51/62) of AQP4-IgG + NMOSD were relapse-free. Independent risk factors of relapse included serum AQP4-IgG titer ≥ 320 at initial disease onset, and severe demyelinating episodes in the first attack. There were no severe side effects. Regular RTX treatment significantly reduces the ARR, incidence of severe relapse, and disability risk in patients with NMOSD.

Long-term efficacy and safety of rituximab in the treatment of neuromyelitis Optica Spectrum disorder

Background

Neuromyelitis optica spectrum disorder (NMOSD) is a relapsing, autoimmune, inflammatory astrocytopathy. Rituximab for B-cell suppression is a common treatment for NMOSD; however, large-scale randomised controlled trials are lacking.

Objective

Evaluate long-term efficacy and safety of rituximab for NMOSD.

Methods

Retrospective observational study of patients with NMOSD treated with rituximab. Annualised relapse rates (ARRs) before and during rituximab treatment were evaluated; Modified Rankin Scores (mRS) were measured as a marker of disability.

Results

In total, 37 patients were included: 27 aquaporin-4-IgG-seropositive and 10 seronegative NMOSD. The predominant rituximab dosing regimen was an initial 1000 mg, split over two 500 mg infusions, two weeks apart, followed by single 500 mg doses. Over a median follow-up of 54 months, ARR for the whole cohort was 0.136 (95% CI 0.088-0.201), significantly lower than the pretreatment ARR of 0.366 (95% CI 0.271-0.483, p < 0.001). There was a significant reduction in ARR for the seropositive subgroup, but not seronegative. Significant improvement in mRS was seen post-treatment. Infections were reported in 32% of patients during follow-up; most were mild.

Conclusion

Rituximab, at doses lower than traditionally used, may be an efficacious therapy for NMOSD, with a favourable safety profile.

Long-Term Efficacy and Safety of Low-Dose Rituximab in Patients with Refractory Myasthenia Gravis

INTRODUCTION

Rituximab is a monoclonal chimeric antibody against CD20+ B cells. We aimed to assess the long-term efficacy and safety of CD20+ B cell-guided treatment with low-dose rituximab in refractory myasthenia gravis patients.

METHODS

Patients with refractory myasthenia gravis treated with rituximab for more than 2 years were included. Rituximab was administered when CD20+ B cells were greater than 1%. We analysed the efficacy of rituximab, treatment interval, side effects, prognosis, and treatment course.

RESULTS

A total of 22 patients were included. All patients received 2-12 doses of rituximab, and the median follow-up time was 48.5 months. The scores of the Myasthenia Gravis Activities of Daily Living and Myasthenia Gravis Composite were significantly lower than those at baseline (p < 0.05). MGFA-PIS was significantly improved in 21 (95.45%) patients and 14 (63.64%) patients have reached MGFA-PIS minimal manifestations. The average daily dose of prednisone and pyridostigmine bromide and the proportion of immunosuppressants were significantly lower (p < 0.05). Seven patients suffered from 14 worsenings. Eight patients terminated rituximab due to good efficacy. Most patients tolerated rituximab well, although 1 patient had opportunistic infection and hypogammaglobulinemia, 1 patient had an intracranial mass.

CONCLUSION

Long-term CD20+ B-cell-guided low-dose rituximab showed good efficacy and tolerance in patients with refractory myasthenia gravis.

Rituximab at lower dose for neuromyelitis optica spectrum disorder: a multicenter, open-label, self-controlled, prospective follow-up study

Objective

To address a novel lower-dose rituximab (RTX) therapy strategy based on our clinical experience and assess its efficacy and safety in neuromyelitis optica spectrum disorder (NMOSD).

Methods

A multicenter, open-label, self-controlled, prospective follow-up study. Totally, 108 NMOSD patients were enrolled and a lower-dose RTX strategy was applied including 100 mg weekly for 3 weeks and then reinfusions every 6 months. Annualized relapse rate (ARR), the expanded disability status scale (EDSS) score and length of spinal cord lesions were included to evaluate the efficacy. Side effects were recorded to assess the safety profile.

Results

Of 108 patients, 80 (74.1%) initiated low-dose RTX therapy immediately after acute attack treatment and 33 (30.6%) initiated it after the first attack. During a median treatment period of 35.5 (22.0-48.8) months, significant decreases were observed in median ARR (1.1 [0.8-2.0] versus 0 [0-0.2], p < 0.001), EDSS score (3.5 [2.5-4.0] versus 2.0 [1.0-3.0], p < 0.001) and spinal cord lesion segments (5.0 [4.0-8.0] versus 3.0 [1.0-6.0], p < 0.001). The cumulative risk of relapses significantly decreased during the post- versus pre-RTX period (HR 0.238, 95%CI 0.160-0.356, p < 0.001) and on early therapy initiated within 24 months after disease onset versus delayed therapy (HR 0.506, 95%CI 0.258-0.994, p = 0.041). No serious side effects were recorded and all the subjects did not discontinue treatment due to RTX-related side effects.

Conclusion

Our research provided evidence supporting the lower-dose RTX strategy in treating NMOSD and reopened the issues of optimal dosage and therapy initiation timing.

Optic Neuritis in the Era of NMOSD and MOGAD: A Survey of Practice Patterns in Singapore

PURPOSE

The Optic Neuritis Treatment Trial was a landmark study with implications worldwide. In the advent of antibody testing for neuromyelitis optica spectrum disease (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), emerging concepts, such as routine antibody testing and management, remain controversial, resulting mostly from studies in White populations. We evaluate the practice patterns of optic neuritis investigation and management by neuro-ophthalmologists and neurologists in Singapore.

DESIGN

21-question online survey consisting of 4 clinical vignettes.

METHODS

The survey was sent to all Singapore Medical Council- registered ophthalmologists and neurologists who regularly manage patients with optic neuritis.

RESULTS

Forty-two recipients (17 formally trained neuro-ophthalmol-ogists [100% response rate] and 25 neurologists) responded. Participants opted for routine testing of anti-aquaporin-4 antibodies (88.1% in mild optic neuritis and 97.6% in severe optic neuritis). Anti-MOG antibodies were frequently obtained (76.2% in mild and 88.1% in severe optic neuritis). Plasmapheresis was rapidly initiated (85.7%) in cases of nonresponse to intravenous steroids, even before obtaining anti-aquaporin-4 or anti-MOG serology results. In both NMOSD and MOGAD, oral mycophenolate mofetil was the preferred option if chronic immunosuppression was necessary. Steroids were given for a longer duration and tapered more gradually than in idiopathic optic neuritis cases.

CONCLUSIONS

Serological testing for NMOSD and MOGAD is considered as a routine procedure in cases of optic neuritis in Singapore, possibly due to local epidemiological features of these conditions. Chronic oral immunosuppression is preferred for the long term, but further research is necessary to establish the efficacy and cost-effectiveness of these practices.