Rituximab Treatment Research Articles

Early progression is associated with worse survival in patients with Waldenström’s macroglobulinemia

Early progression of disease within 24 months (POD24) of diagnosis is associated with inferior overall survival (OS) in follicular lymphoma, but its prognostic role in Waldenström’s macroglobulinemia (WM) is still unclear. Here, we performed a retrospective analysis of 373 patients pooled from the database of the Chinese Registration Network for WM (CRNWM) to determine the outcomes of early progressors. POD24 occurred in 98 evaluable patients (26.3%). The median OS in patients with POD24 was 40 months (95%CI: 15.2–64.0), which was significantly shorter than that without POD24 (156 months, 95%CI: 123.6–188.4; HR: 6.587, 95% CI 4.392–9.881, P < 0.0001). Moreover, subgroup analysis showed that POD24 still maintained its predictive ability of inferior OS in patients treated with rituximab or bortezomib-based treatment. Patients with a very high-risk rIPSSWM stage were more likely to have POD24 (P = 0.020). In conclusion, POD24 was associated with poorer survival and may represent a useful endpoint in future prospective clinical trials.

Rituximab-induced gut microbiota changes in Chinese neuromyelitis optica spectrum disorders

BackgroundRecent evidence shows that immunosuppressive agents can affect the gut microbiota in autoimmune diseases. However, the relationship between the gut microbiome and B-cell depletion immunotherapy in neuromyelitis optica spectrum disorder (NMOSD) remains poorly understood. ObjectivesTo evaluate the distinct intestinal microbial patterns and serum cytokine levels after short-term rituximab treatment (three months) in patients with NMOSD. MethodsFirstly, we conducted a cross-sectional study involving 46 treatment-naïve NMOSD patients and 48 matched healthy controls. We collected fecal specimens, which were then analyzed using next-generation sequencing, and quantified serum cytokines. Subsequently, fecal and serum samples were re-collected and re-evaluated in 31 of the 46 treatment-naïve NMOSD patients after RTX treatment. ResultsComparing the gut microbiome of treatment-naïve NMOSD patients to that of healthy controls revealed low α-diversity and distinct microbial compositions in the former. The microbial composition in NMOSD patients underwent changes following three months of RTX treatment. Specifically, the levels of IL-17F and IL-6 decreased, while those of IL-10 and TNFα increased after RTX treatment. LEfSe analysis identified 27 KEGG categories with significantly differential abundances between NMOSD patients and RTX treatment group. ConclusionsOur study provides a comprehensive understanding of the gut microbiota landscape in the context of B-cell depletion immunotherapy. We observed dysbiosis in the gut microbiome of NMOSD patients, which was partially alleviated by three months of RTX treatment. This suggests that B-cell depletion may play a crucial role in driving changes in the gastrointestinal environment.

Rituximab in Childhood and Juvenile Pemphigus Vulgaris: A Systematic Review.

Pemphigus vulgaris (PV) is a chronic autoimmune blistering disorder characterized by the loss of intraepithelial adhesion, affecting the skin and mucous membranes. Both males and females are affected, although it predominantly affects females in their fifth and sixth decades of life. Approximately 1.4 to 3.7% of PV cases occur in the pediatric population (≤18 years of age), and may be classified into childhood/pediatric PV, which affects individuals under 12 years old, and juvenile/adolescent PV, affecting those between 12 and 18 years old. Due to its rare occurrence in children and adolescents, there is often a delay in diagnosis and treatment in this age group. A systematic literature search was conducted on MEDLINE/PubMed, Web of Science, EMBASE, SCOPUS, and Cochrane Library databases to evaluate the efficacy of rituximab (RTX) in childhood and juvenile PV patients. The Joanna Briggs Institute (JBI) Critical Appraisal Checklist was employed to assess the risk of bias in case reports and series, while the Cochrane ROBINS-I tool was utilized for evaluating observational studies or non-randomized intervention studies. A total of 18 studies encompassing 46 juvenile or childhood PV patients in the pediatric and adolescent age groups were included for qualitative synthesis. The studies included nine case reports, two case series, five retrospective studies, one prospective study, and one open-label pilot study. Almost all cases of childhood and juvenile PV achieved either complete or partial remission after undergoing RTX treatment during the final follow-up periods. Furthermore, most cases reported no relapse, and only minor adverse events were noted in the RTX treatment group. Despite its potential benefits, the utilization of RTX in pediatric patients raises concerns due to the scarcity of evidence and the absence of controlled studies specific to this age group. Further exploration is necessary to establish a standardized treatment regimen for RTX in pediatric PV, which involves identifying the optimal dosage, frequency, treatment cycle duration, and maintenance therapy duration.

Additive and Dose-Dependent Effect of Rituximab on Pediatric Patients’ Outcomes Concurrently Receiving Immunosuppressive Chemotherapy, A Prospective Cohort Study

Background: Rituximab (RTX) is approved for treating CD20-positive B-cell malignancies, including non-Hodgkin lymphoma, when used alongside chemotherapy. It has the potential to interact with and alter the host immune system, putting patients at a heightened risk of infection. Therefore, the use of RTX necessitates a meticulous assessment of infectious risks based on the latest evidence. Objectives: We conducted a prospective investigation into infectious complications and mortality among children undergoing RTX treatment over the observation period of the study. Methods: In this observational cohort study, we included 61 pediatric patients treated with RTX for malignancy and immune thrombocytopenic purpura (ITP), as well as 122 cancer patients who had never received RTX (the unexposed group). These patients were prospectively monitored for febrile neutropenia (FN), bloodstream infection (BSI), invasive fungal infection (IFI), and mortality. All infectious complications were documented starting from the initial dose of RTX and continuing for at least six months following the last dose. Logistic regression and Cox regression analyses, with consideration for the proportional hazards assumption, were utilized to evaluate the impact of covariates on mortality and infection-related outcomes. Results: Infectious complications were observed in 52.5% of children treated with RTX. These complications were notably more prevalent in children with malignancy compared to those with chronic ITP (89.5% versus 10.5%, respectively). RTX was found to be associated with an increased likelihood of mortality in children with malignancy (OR [95% CI]: 1.54 [0.41, 5.69]). According to Cox regression analysis, RTX was linked to a higher risk of IFIs, death, FN events, and BSIs over a 36-month observation period (4.33 [1.21, 15.52], 3.26 [1.008, 10.59], 1.68 [0.83, 3.41], and 1.59 [0.27, 9.17], respectively). The total dose of RTX administered was also associated with adverse patient outcomes, with the odds of infectious events and death increasing in the second, third, and fourth quartiles of the total RTX dose administered. Furthermore, the estimated one-year and two-year survival rates for cancer patients treated with RTX were 77% and 58%, respectively. Conclusions: RTX treatment, when used concurrently with immunosuppressive chemotherapy for hematologic malignancies in children, showed additive and dose-dependent effects on clinical outcomes.

Eruptive Nevus Following Rituximab Treatment: Unusual Dermoscopic Presentation: A Case Report

Background: Eruptive nevi can occur following various conditions, including the use of immunosuppressive and immunomodulatory drugs such as biologics. Dermoscopy typically reveals a pattern of brown globules arranged in a ring at the periphery. We report a case of eruptive nevus with an atypical dermoscopic pattern in a patient receiving Rituximab. Observation: A 37-year-old female patient, followed for acquired bullous epidermolysis, developed pigmented and extensive macules six months later. Dermoscopy of a lesion on the trunk, which was increasing in size, showed a homogeneous brown pattern with irregularly arranged brown globules and dots at the center and periphery. Biopsy revealed a junctional nevus. Conclusion: The atypical brown pattern on dermoscopy of eruptive nevi is described for the first time, particularly after rituximab therapy.

Combined Rituximab and Daratumumab Treatment in Difficult-to-Treat Nephrotic Syndrome Cases

Combined Rituximab and Daratumumab Treatment in Difficult-to-Treat Nephrotic Syndrome Cases

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

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. Evaluate long-term efficacy and safety of rituximab for NMOSD. 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. 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. Rituximab, at doses lower than traditionally used, may be an efficacious therapy for NMOSD, with a favourable safety profile.

Prolonged viral shedding following COVID-19 infection in a rheumatoid patient on rituximab treatment.

Prolonged viral shedding following COVID-19 infection in a rheumatoid patient on rituximab treatment.

Japanese clinical practice patterns of rituximab treatment for minimal change disease in adults 2021: A web-based questionnaire survey of certified nephrologists.

In Japan, rituximab (RTX) for adult-onset frequently relapsing (FR)/steroid-dependent (SD) minimal change disease (MCD) is not explicitly reimbursed by insurance, and its standard regimen has not been established. We conducted a cross-sectional web-based survey between November and December 2021. The participants were nephrologists certified by the Japanese Society of Nephrology and answered 7 items about RTX for adult MCD. Factors related to the experience of RTX administration at their facilities were estimated by generalized estimating equations. Of 380 respondents, 181 (47.6%) reported the experience of RTX use for adult MCD at their current facilities. Those who worked at university hospitals (vs. non-university hospitals, proportion difference 13.7%) and at facilities with frequent kidney biopsies (vs. 0 cases/year, 19.2% for 1-40 cases/year; 37.9% for 41-80 cases/year; 51.9% for ≥ 81 cases/year) used RTX more frequently. Of 181 respondents, 28 (15.5%) answered that there was no insurance coverage for RTX treatment. Of 327 respondents who had the opportunity to treat MCD, which was a possible indication for RTX, 178 (54.4%) indicated withholding of RTX administration. The most common reason was the cost due to lack of insurance coverage (141, 79.2%). Regarding RTX regimens for FR/SD MCD, introduction treatment with a single body surface area-based dose of 375 mg/m2 and maintenance treatment with a 6-month interval were the most common. This survey revealed the nephrologists' characteristics associated with RTX use, the barriers to RTX use, and the variation in the regimens for adult MCD in Japan.

Abstract 2836: Assessment of therapeutic antibody efficacy without the interference of murine Fc receptors allows for investigation of human antibody-dependent cellular cytotoxicity mediated by NK cells in the FcResolv™ hIL-15 NOG mouse model

Abstract Targeted antibody therapy is applied to treat various cancer types. In addition to the primary mode of action (MOA), which involves direct binding to the tumor antigen, indirect MOA acting through the constant region (Fc) of the antibody can enhance anti-tumor efficacy. Indirect mechanisms engage the innate immune system, mediated by both the complement system (complement-dependent cytotoxicity (CDC)) and immune cells (antibody-dependent cellular phagocytosis (ADCP) and antibody-dependent cellular cytotoxicity (ADCC)). These indirect mechanisms can complicate the evaluation and accurate assessment of antibody-induced ADCC by human NK cells in current mouse models. In immune-deficient mouse strains (e.g. NOG), false positives and/or negatives may occur due to interactions with murine Fc receptors. These can either result in anti-tumor responses via activation of the murine innate immune system or can interfere with the human-targeted therapy's primary MOA. To study the response to anti-cancer antibodies without the interference of these murine Fc receptor interactions and to investigate ADCC mediated by human NK cells, a novel mouse model deficient in Fc receptors and expressing human IL-15 (FcResolv™ hIL-15 NOG) was employed for testing antibody therapies. Methods: Patient-derived xenograft (PDX) tumor models were transplanted into hIL-15 NOG and FcResolv™ hIL-15 NOG mice. A human head and neck squamous cell carcinoma and a lung adenocarcinoma PDX model were both treated with cetuximab. Treatment with pertuzumab and trastuzumab was applied in a breast ductal carcinoma PDX model. Rituximab treatment was tested in two diffuse large B cell lymphoma PDX models. Based on growth kinetics, the lung cancer PDX model was chosen for further testing of ADCC in the NK cell-humanized FcResolv™ hIL-15 NOG mouse. Results and Conclusion: There was no difference in percent tumor growth inhibition between the FcResolv™ hIL-15 NOG and hIL-15 NOG mice with regards to cetuximab treatment in the lung and head and neck cancer or for trastuzumab treatment of breast ductal carcinoma. However, pertuzumab treatment revealed a false positive efficacy, with the false positive effect more pronounced in hIL-15 NOG mice than in FcResolv™ hIL-15 NOG mice. In one of the lymphoma models, a false negative result was observed. Here, rituximab did not show notable tumor inhibition in the hIL-15 NOG mice but did in the FcResolv™ hIL-15 NOG mice. These results demonstrate that FcResolv™ hIL-15 NOG mice serve as a suitable mouse model for a more accurate assessment of the therapeutic efficacy of anti-tumor antibodies. Additionally, evaluation of human-mediated ADCC of therapeutic antibodies in NK cell-humanized FcResolv™ hIL-15 NOG allows detection of effects specifically mediated by human NK cells. Citation Format: Simone Rhein, Maria Stecklum, Monika Buczek, Janell Richardson, Jens Hoffmann. Assessment of therapeutic antibody efficacy without the interference of murine Fc receptors allows for investigation of human antibody-dependent cellular cytotoxicity mediated by NK cells in the FcResolv™ hIL-15 NOG mouse model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2836.

Sensitive B-cell receptor repertoire analysis shows repopulation correlates with clinical response to rituximab in rheumatoid arthritis

BackgroundAlthough B-cell depleting therapy in rheumatoid arthritis (RA) is clearly effective, response is variable and does not correlate with B cell depletion itself.MethodsThe B-cell receptor (BCR) repertoire was prospectively analyzed in peripheral blood samples of twenty-eight RA patients undergoing rituximab therapy. Timepoints of achieved BCR-depletion and -repopulation were defined based on the percentage of unmutated BCRs in the repertoire. The predictive value of early BCR-depletion (within one-month post-treatment) and early BCR-repopulation (within 6 months post-treatment) on clinical response was assessed.ResultsWe observed changes in the peripheral blood BCR repertoire after rituximab treatment, i.e., increased clonal expansion, decreased clonal diversification and increased mutation load which persisted up to 12 months after treatment, but started to revert at month 6. Early BCR depletion was not associated with early clinical response but late depleters did show early response. Patients with early repopulation with unmutated BCRs showed a significant decrease in disease activity in the interval 6 to 12 months. Development of anti-drug antibodies non-significantly correlated with more BCR repopulation.ConclusionOur findings indicate that rather than BCR-depletion it is repopulation with unmutated BCRs, possibly from naïve B cells, which induces remission. This suggests that (pre-existing) differences in B-cell turnover between patients explain the interindividual differences in early clinical effect.

Cancer risk with tocilizumab/sarilumab, abatacept, and rituximab treatment in patients with rheumatoid arthritis: a Danish cohort study.

To investigate cancer risk in rheumatoid arthritis (RA) patients treated with tocilizumab/sarilumab, abatacept, or rituximab compared with those who received tumour necrosis factor inhibitors (TNFi) and compared with biological disease-modifying anti-rheumatic drugs (bDMARD) naïve RA patients. Nationwide registry-based cohort study of RA patients initiating treatment with tocilizumab/sarilumab, abatacept, rituximab, TNFi, and bDMARD-naive patients their second type of conventional synthetic DMARD (csDMARD). Patients were identified in DANBIO and followed for cancer from 2006-2020. Patients could contribute multiple treatments, with person years (PYRS), deaths, and cancers allocated to each treatment group in a 'latest type of treatment' manner. Inverse probability of treatment weighting and weighted cause-specific Cox models were used to calculate hazard ratios (HRs) for cancer in each tocilizumab/sarilumab, abatacept, and rituximab group compared with TNFI and bDMARD naïve groups, respectively. In total, 21 982 treatment initiations, 96 475 PYRS, and 1423 cancers were identified. There were no statistically significant increased HRs for overall cancer in tocilizumab/sarilumab, abatacept, or rituximab treatment groups (HRs ranged from 0.7-1.1). More than five years of abatacept exposure showed a non-significantly increased HR compared with TNFi (HR 1.41, 95% confidence intervals CI 0.74-2.71). For hematological cancers, rituximab treatment showed non-significantly reduced HRs: vs TNFi (HR 0.09; 95%CI 0.00-2.06) and bDMARD-naïve (HR 0.13; 95%CI 0.00-1.89). Treatment with tocilizumab/sarilumab, abatacept, or rituximab in RA patients was not associated with increased risks of cancer compared with TNFi-treated and with bDMARD-naïve RA patients in a real-world setting.

Impact of rituximab treatment regime on time to relapse in aquaporin-4 antibody positive neuromyelitis optica spectrum disorder

BackgroundAquaporin-4 (AQP4) antibody associated neuromyelitis optica (NMOSD) requires long-term immunosuppression. Rituximab is increasingly used worldwide, however the optimal regime is not established. MethodsWe retrospectively examined different rituximab regimens in AQP4-NMOSD. Standard monotherapy (SM; 6 monthly infusions), SM plus oral steroids (SM+S), extended interval dosing (EID; guided by CD19 repopulation) and EID with oral steroids (EID+S) were compared. The primary outcome was time to first clinical relapse. Potential confounders including age, gender, number of previous relapses, and onset phenotype were included. Results77 patients were included: 67 females, median onset age 35.6, median DSS at rituximab initiation 5.0. 39 were on SM+S, 20 SM, 6 EID, and 12 EID+S. 25/77 patients relapsed during a median follow-up of 44.0 months. No significant difference in time to first relapse was observed between any rituximab regimen. Pooled analyses to compare regimens that use standard monotherapy (SM and SM+S) against those that use extended interval dosing (EID and EID+S) showed no significant difference. Pooled analysis of regimens using steroids with those not using steroids also showed no significant difference. Adjusted Cox proportional hazard model revealed no significant difference between rituximab regimens or influence of demographic factors. 9 significant adverse events were recorded, 5 in the SM group and 4 in SM+S. ConclusionsThis study provides some basis for further exploring EID as a viable option for long term treatment of AQP4-NMOSD. This may improve patient experience and consolidate use of hospital resources.

Rituximab may affect T lymphocyte subsets balance in primary membranous nephropathy

BackgroundThe aim of this study was to investigate the effects and significance of rituximab (RTX) on the levels of T lymphocyte subsets in patients diagnosed with primary membranous nephropathy (PMN).MethodsA total of 58 PMN patients and 25 healthy donors were chosen as the subjects. Among the PMN patients, 40 individuals received RTX treatment and completed at least 6 months of follow-up. All subjects underwent flow cytometry analysis to determine the peripheral blood lymphocyte subsets. The changes in anti-PLA2R antibody titers and 24-hour urinary protein levels were evaluated by ELISA and Biuret method before and after treatment.Results(1) The PMN group exhibited a significantly greater percentage of peripheral blood CD3−CD19+ B cells than the healthy group, which is consistent with the findings of previous reports. Additionally, compared with those in the peripheral blood of healthy individuals, the numbers of CD4+ central memory T cells, CD4+ effector memory T cells, CD4+/CD8+, and CD4+CD25+ T cells in the PMN peripheral blood were markedly greater. However, the number of peripheral blood Treg cells was reduced in the PMN group. (2) After 6 months of RTX treatment, PMN patients exhibited significant decreases in anti-PLA2R antibody titers, 24-hour urinary protein levels, and peripheral blood CD3−CD19+ B cells. Importantly, RTX administration decreased CD4+CD25+ T cells and CD4+/CD8+ in the peripheral blood of PMN patients and improved Treg cell levels. (3) RTX treatment induced alterations in the CD4+ T lymphocyte subsets in PMN patients, which did not correlate with B lymphocyte counts or anti-PLA2R antibody titers.ConclusionsRTX treatment might have a beneficial impact on cellular immunity by effectively restoring the balance of CD4+ T lymphocyte subsets in PMN patients, which is beyond its effects on B cells and antibody production.Trial registrationThe research was registered at the First Affiliated Hospital of Soochow University. Registration Number: MR-32-23-016211. Registration Date: May 31, 2023.

The serological immunogenicity of the third and fourth doses of COVID-19 vaccine in patients with inflammatory rheumatic diseases on different biologic or targeted DMARDs: a Swedish nationwide study (COVID-19-REUMA).

Results from this study provide further evidence that additional doses of COVID-19 vaccines are immunogenic and result in satisfactory antibody response in a majority of patients with inflammatory rheumatic diseases (IRD) receiving potent immunomodulating treatments such as biological or targeted disease-modifying anti-rheumatic drugs (DMARDs) given as monotherapy or combined with traditional DMARDs. We observed that rituximab treatment, both as monotherapy and combined with csDMARDs, impaired antibody response, and only roughly 50% of patients developed a satisfactory antibody response including response to omicron subvariants after the third vaccine. In addition, higher IgG levels at the last rituximab course before the third vaccine dose and a longer time after the last rituximab treatment increased the chance of a satisfactory antibody response. These results indicate that rituximab-treated patients should be prioritized for additional vaccine doses. EudraCT (European Union Drug Regulating Authorities Clinical Trials Database) with number 2021-000880-63.

VARICELLA-ZOSTER VIRUS INFECTION IN A PATIENT 12 DAYS POST RITUXIMAB: UNUSUAL CO-PRESENTATION OF SHINGLES AND CHICKENPOX

Rituximab, an anti CD20 monoclonal antibody, is used in the management of lymphoproliferative and autoimmune conditions such as pemphigus. As an immunosuppressor, it exposes patients to an increased risk of infection. Two cases of varicella-zoster virus infection post Rituximab were been reported in literature. The coexistence of chickenpox (primary infection) and shingles (reactivation of latent infection) in the same patient has never been reported in the literature, especially after rituximab treatment. Herein we present the first case of association of these 2 manifestations in a patient 12 days after rituximab therapy for pemphigus.

Patients with infusion-related reactions on fixed-dose rituximab treatment have higher body surface area than those without infusion-related reactions in adults with frequently relapsing minimal change nephrotic syndrome: a retrospective study

BackgroundInfusion-related reactions (IRRs) are major side effects of rituximab administration. Male sex, high body weight, body surface area (BSA), and body mass index are predictive markers of rituximab-induced IRRs. However, as rituximab was not administered at a fixed dosage in a previous study, whether a higher dosage or factors associated with a larger physique are more strongly associated with rituximab-induced IRRs is unknown.Main bodyThirteen adults with frequently relapsing minimal change nephrotic syndrome (MCNS) who received an initial rituximab dose of 500 mg between September 2015 and November 2022 were retrospectively evaluated. Data on IRRs were collected from medical records. The incidence of rituximab-induced IRRs was 38.5% (5/13). The IRR group had a significantly higher BSA than the non-IRR group (median, 1.86 vs. 1.48 m2; p = 0.045). Additionally, rituximab dosage normalized by BSA in the IRR group was significantly lower than that in the non-IRR group (median, 268.8 vs. 337.9 mg/m2; p = 0.045).ConclusionsOur study revealed that adults with frequently relapsing MCNS who experienced IRRs tend to have a higher BSA, even with fixed-dose rituximab treatment. Therefore, when patients with higher BSA receive rituximab treatment, clinicians should be careful about monitoring patient condition whether the dosage is fixed or not.

AT1-AA Is Produced in Offspring in Response to Placental Ischemia and Is Lowered by B-Cell Depletion Without Compromising Overall Offspring Health.

Preeclampsia, new-onset hypertension during pregnancy alongside other organ dysfunction, is the leading cause of mortality for the mother and low birth weight for the baby. Low birth weight contributes to high risk of cardiovascular disorders later in life. Women with preeclampsia have activated B cells producing agonistic autoantibodies to AT1-AA (angiotensin II type I receptor). We hypothesize that rituximab, a B cell-depleting chemotherapeutic, will deplete maternal B cells in reduced uterine perfusion pressure (RUPP) rats without worsening the effect of placental ischemia on pup growth and survival. To test this hypothesis, the RUPP procedure was performed, and rituximab was continuously infused via miniosmotic pump. Maternal blood and tissues were collected. A separate group of dams were allowed to deliver, pup weights were recorded, and at 4 months of age, tissues were collected from offspring. Immune cells were measured via flow cytometry, and AT1-AA was quantified using a contraction bioassay. Blood pressure increased in RUPP rats and was normalized with rituximab treatment. RUPP offspring also had increased circulating B cells, cytolytic natural killer cells, and increased circulating AT1-AA, which were normalized with maternal rituximab treatment. This is the first study to analyze the AT1-AA in RUPP offspring, which was normalized with rituximab. Our findings indicate that perinatal rituximab lowers maternal mean arterial pressure in RUPP rats and improves birth weight, circulating AT1-AA, and circulating natural killer cells, indicating that rituximab improves adverse fetal outcomes in response to placental ischemia.

Progressive multifocal leukoencephalopathy associated with rituximab treatment.

Progressive multifocal leukoencephalopathy associated with rituximab treatment.

Incidence of hypogammaglobulinaemia in children with steroid-dependent/frequently relapsing nephrotic syndrome treated with rituximab and its association with severe infections

Objective: To investigate the incidence and influencing factors of hypogammaglobulinemia (HGG) in children with steroid-dependent/frequently relapsing nephrotic syndrome (SDNS/FRNS) treated with rituximab (RTX), and its relationship with the risk of severe infections. Methods: The clinical data of children with SDNS/FRNS treated with RTX at the Department of Pediatrics of the First Affiliated Hospital of Zhengzhou University from December 2020 to January 2023 were retrospectively analyzed. RTX treatment was performed using a B-cell-guided regimen (a single dose of 375 mg/m2, a maximum of 500 mg/dose, and an additional one dose when reassessment of peripheral blood CD19+B cells≥1%). Patients were divided into HGG and non-HGG groups according to the presence or absence of HGG during the follow-up period. A multivariate logistic regression model was used to analyze the influencing factors of HGG, and the predictive value of each influencing factor on HGG was assessed by plotting the receiver operating characteristic (ROC) curve. Results: A total of 59 SDNS/FRNS children (48 males and 11 females) were included, and aged [M (Q1, Q3)] 9.4 (6.5, 12.2) years at the time of the first RTX treatment, with a median application of 3 (2, 4) doses of RTX. During the follow-up period of 15.5 (9.9, 22.8) months, the HGG was present in 16 (27.1%) children, of which seven persisted for more than 1 year. Compared with non-HGG group, HGG group had a shorter duration of the disease [3.3 (2.1, 3.6) vs 4.6 (2.4, 8.0) years, P=0.030], younger age at the time of the first RTX treatment [6.2 (5.6, 7.4) vs 11.3 (8.8, 13.3) years, P<0.001], and lower serum IgG levels [5.9 (4.9, 6.4) vs 7.5 (6.1, 8.2) g/L, P<0.001]. Multivariate logistic regression analysis showed that young age at the time of the first RTX treatment (OR=0.52, 95%CI: 0.35-0.78, P=0.002) was an influencing factor of HGG. The area under the curve (AUC) for age at first RTX treatment to predict HGG was 0.887 (95%CI: 0.778-0.955, P<0.001), with an optimal cut-off value of 8.3 years. During the follow-up period, six children (10.2%) developed severe infectious, and there was no statistically significant difference in the incidence of serious infections between the HGG and non-HGG groups [12.5% (2/16) vs 9.3% (4/43), P=1.000]. Conclusions: HGG is frequent in children with SDNS/FRNS treated with RTX, and nearly half of HGG persists for more than 1 year. The possibility of HGG is greater in those≤8.3 years at the first RTX treatment, but HGG does not increase the risk of severe infections in children.