RESUMEN
Background: Recent studies have reported that similar to other IgG4 autoimmune diseases, such as muscle-specific kinase antibody-associated myasthenia gravis, most anti-neurofascin-155 (anti-NF155) nodopathies respond well to rituximab treatment, regardless of the dosage. However, there are still a few patients for which rituximab is ineffective for unknown reasons. Currently, there are no studies on the mechanism of ineffective treatment with rituximab. Methods: A 33-year-old Chinese man presenting with numbness, tremor, and muscle weakness for 4 years was recruited for this study. Anti-NF155 antibodies were identified by cell-based assay and confirmed by immunofluorescence assay on teased fibers. The anti-NF155 immunoglobulin (IgG) subclasses were also detected by immunofluorescence assay. Anti-rituximab antibodies (ARAs) were quantitatively analyzed using enzyme-linked immunosorbent assay (ELISA), and peripheral B cell counts were determined by flow cytometry. Results: The patient exhibited anti-NF155 IgG4-antibody positivity. After the first round of rituximab infusion, the patient showed stratified outcomes with improvements in numbness, muscle weakness and ambulation. However, after three rounds of rituximab infusion, the patient's symptoms deteriorated, and the numbness, tremor and muscle weakness returned. No obvious improvement was found after plasma exchange and another round of rituximab treatment. 14 days after the last treatment with rituximab, ARAs were detected. And the titers gradually decreased on day 28 and 60 but remained higher than normal. Peripheral CD19+ B cell counts were less than 1% within the 2-month period following the final rituximab administration. Conclusions: In this study, ARAs presented in a patient with anti-NF155 nodopathy undergoing rituximab treatment and showed an unfavorable impact on rituximab efficacy. This is the first case to report the occurrence of ARAs in patients with anti-NF155 antibodies. We suggest that ARAs should be tested early during the initial intervention, especially in patients who respond poorly to rituximab treatment. In addition, we believe it is necessary to investigate the association between ARAs and B cell counts, their effect on clinical efficacy, and their potential adverse reactions in a larger cohort of patients with anti-NF155 nodopathy.
Asunto(s)
Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante , Temblor , Masculino , Humanos , Adulto , Rituximab/uso terapéutico , Hipoestesia , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/diagnóstico , Autoanticuerpos , Moléculas de Adhesión Celular , Inmunoglobulina G , Debilidad MuscularRESUMEN
The utilization of the monoclonal antibodies (mAbs) as therapeutic agents is one of the most favourable fields in immunotherapy. The immunogenicity of mAbs is one of the major parameters that may restrict their therapeutic and diagnostic applications. Rituximab, a chimeric mAb against CD20, is attached to the B-cell membrane-linked CD20 and is used to treat some B-cell-related malignancies, a number of autoantibody-mediated autoimmune disorders and improvement of graft survival. The risk of anti-rituximab antibody (ARA) development and ARA-related adverse events are low in rituximab-treated patients with lymphoma. No important association was reported between the ARA positivity and drug levels, and drug efficacy in rituximab-treated patients with lymphoma. The patients with autoimmune disorders exhibit greater risk of ARA development and ARA-related adverse events. In autoimmune diseases, ARA positivity may have no significant impact on either the drug level or its efficacy, (i.e.), it may reduce drug levels without influencing drug efficacy and, vice versa, or may reduce both drug level as well as its efficacy. The characterization of the parameters affecting the production of ARA can be used to design strategies to reduce the immunogenicity of mAb and promote its efficacy in humans. In this review, the host and therapeutic programme-related parameters affecting the development of the ARA have been discussed to suggest novel insights to reduce ARA-associated adverse events and enhance the drug efficacy.
Asunto(s)
Antígenos CD20 , Enfermedades Autoinmunes , Anticuerpos Monoclonales/uso terapéutico , Enfermedades Autoinmunes/tratamiento farmacológico , Linfocitos B , Humanos , Rituximab/efectos adversosRESUMEN
BACKGROUND: Anti-rituximab antibodies (ARA) are associated not only with adverse events, such as infusion reactions (IR) and serum sickness, but also with rituximab efficacy. However, the clinical relevance of ARA in children with steroid-dependent nephrotic syndrome (SDNS) remains unknown. METHODS: We retrospectively reviewed clinical outcomes of 13 children with complicated SDNS receiving repeated single-dose rituximab treatments at 375 mg/m2 to assess whether ARA formation could impact toxicity and efficacy of additional rituximab. Pre-rituximab 22 samples collected from patients who developed IR during the second or subsequent rituximab doses were measured by electrochemiluminescence analysis. RESULTS: ARA were identified in 5 of 13 patients (9 of 22 samples). Median time to recovery of CD19+ B cells to > 1% of total lymphocytes and median relapse-free time after rituximab treatment were significantly shorter in the 9 ARA-positive samples than the 13 ARA-negative samples (41 vs. 100 days, p < 0.01 and 119 vs. 308 days, p < 0.05, respectively). Kaplan-Meier analysis showed that time to CD19+ B cell recovery after rituximab was significantly shorter in ARA-positive samples than in ARA-negative samples (p < 0.005). Severe IR developed in two ARA-positive patients and serum sickness in one ARA-positive patient. CONCLUSIONS: The incidence of ARA formation was high in the pre-rituximab samples of patients with complicated SDNS who developed IR during the second or subsequent rituximab doses, suggesting that ARA formation might have an unfavorable impact on the toxicity and efficacy of additional rituximab doses in these patients.
Asunto(s)
Anticuerpos/sangre , Hipersensibilidad a las Drogas/epidemiología , Glucocorticoides/uso terapéutico , Síndrome Nefrótico/tratamiento farmacológico , Rituximab/inmunología , Anticuerpos/inmunología , Antígenos CD19 , Linfocitos B/inmunología , Linfocitos B/metabolismo , Niño , Preescolar , Hipersensibilidad a las Drogas/sangre , Hipersensibilidad a las Drogas/diagnóstico , Hipersensibilidad a las Drogas/inmunología , Resistencia a Medicamentos/inmunología , Femenino , Humanos , Incidencia , Lactante , Infusiones Intravenosas , Masculino , Síndrome Nefrótico/sangre , Síndrome Nefrótico/inmunología , Estudios Retrospectivos , Rituximab/administración & dosificación , Rituximab/efectos adversos , Índice de Severidad de la EnfermedadRESUMEN
BACKGROUND: Rituximab is a mouse-human chimeric anti-CD20 monoclonal antibody and has been increasingly used for preventing relapses in NMOSDs. The clinical relevance of Anti-Rituximab antibodies (ARA) against Rituximab in NMOSDs is unknown. METHODS: Nineteen NMOSDs patients receiving repeated 100mg Rituximab treatment were recruited. The ARA was quantitatively analyzed by enzyme linked immunoassay. Annualized relapse rate (ARR) and Expanded Disability Status Scale (EDSS) were analyzed concurrently. RESULTS: ARR was reduced markedly since starting Rituximab therapy in the majority (78.9%) of NMOSDs patients. 36.9% (7/19) patients were ARA positive. There was no significant difference in the improvement of ARR and EDSS after treatment with Rituximab in either ARA positive or negative groups. The frequency of Rituximab reinfusion was higher in patients with ARA, suggesting that the presence of ARA led to an increased frequency of Rituximab reinfusion to maintain B cell depletion. CONCLUSION: The majority of (78.9%) patients with NMOSDs were responsive to low dose Rituximab. The presence of ARA is associated with the requirement for increased frequency of Rituximab reinfusion to maintain treatment response in NMOSDs. In patients with ARA it might be necessary to detect ARA levels and monitor B cell depletion closely, or even attempt other treatments.