rituximab (Kikuzubam / PBO326)

Rituximab in Myasthenia Gravis: a real-world study using inverse probability of treatment weighting.

Wang Yong Lin YL, Zhu Chao C, Kapoor Mahima M, Cutter Gary G et al.

The role of rituximab in the treatment of myasthenia gravis (MG) remains uncertain due to limited randomized controlled evidence and heterogeneous observational data. While rituximab is often used in refractory MG, its comparative effectiveness against other non-steroidal immunosuppressive therapies (NSISTs) has yet to be fully clarified. To evaluate the effectiveness of rituximab compared to a second NSIST in achieving a composite clinical outcome in acetylcholine-receptor-antibody (AChR-Ab) positive MG patients using causal inference methods to adjust for confounding. We conducted a retrospective cohort study of AChR-Ab positive MG patients treated with rituximab or a second NSIST. The primary outcome was time to achieving a composite clinical endpoint representing a patient acceptable symptom state (PASS): Myasthenia Gravis Composite (MGC) score ≤ 3, daily corticosteroid dose ≤ 5 mg prednisolone equivalent, and no rescue therapy use in the preceding month. To reduce confounding by indication and improve causal comparability between treatment groups, inverse probability of treatment weighting (IPTW) based on propensity scores was used to balance baseline covariates. Cox proportional hazards models were applied to estimate the effect of treatment on time to outcome. 169 patients entered into the time-to-event analysis, and after IPTW adjustment, baseline characteristics between treatment groups were balanced. There was no statistical difference in the hazard ratio between Rituximab compared to a second NSIST in achieving the composite clinical outcome (HR = 1.27, 95% CI 0.66-2.45, p = 0.48). In this IPTW-adjusted analysis, rituximab did not improve the time-to-improvement compared to a second NSIST in AChR-Ab-positive MG.

Relapse prediction in rituximab-treated pemphigus patients: A prognostic model.

Zhang Aobei A, Zhang Youzhuo Y, Shang Panpan P, Zhang Chuang C et al.

A Rare Diagnostic Dilemma of P-ANCA/MPO Positive Crescentic Glomerulonephritis in an Immunosuppressed Lupus Patient.

Elrefy Omar O, Carpenter Sweta S, Saini Manu M, Balasubramanian Manjula M et al.

Perinuclear antineutrophil cytoplasmic antibodies (P-ANCAs) and myeloperoxidase (MPO) antibodies are detected in 15%-25% of lupus nephritis patients, but systemic lupus erythematosus (SLE)/ANCA-associated vasculitis (AAV) overlap syndrome is rare, occurring in approximately 2% of cases. We present a 57-year-old woman with SLE and antiphospholipid syndrome (APS) on belimumab, hydroxychloroquine, and prednisone, who presented with acute ischemic stroke requiring thrombectomy and rapidly progressive renal failure (creatinine rising from 1.1 to 5.2 mg/dL) with nephrotic-range proteinuria (8.6 g/g). P-ANCA titer was > 1:640 with MPO positivity, while anti-dsDNA, C3, and C4 were normal. Kidney biopsy revealed crescentic glomerulonephritis with neutrophil-rich infiltrates and immune complex deposits on electron microscopy but without "full house" immunofluorescence, favoring SLE/AAV overlap rather than isolated lupus nephritis flare. Treatment with methylprednisolone, rituximab, and anticoagulation resulted in significant renal recovery (creatinine 1.7 mg/dL, proteinuria 4.4 g/g). This case highlights the importance of ANCA testing in SLE patients with unexplained rapidly progressive glomerulonephritis, as early recognition of overlap syndrome carries distinct therapeutic implications, including the use of rituximab-based regimens targeting both disease processes.

Dose-reduced (24 Gy) involved-site radiotherapy combined with rituximab in early-stage non-gastric mucosa-associated lymphoid tissue lymphoma: a prospective phase II trial.

Liu Hailing H, Cheng Yuexin Y, Liu Shu S, Zhang Xiaohui X et al.

While involved-site radiotherapy (ISRT) is the standard first-line treatment in localized non-gastric mucosa-associated lymphoid tissue (MALT) lymphoma, the cumulative risk of distant relapse poses a persistent clinical challenge. We conducted a prospective phase II trial evaluating rituximab with 24 Gy ISRT, aiming to reduce distant relapse and enhance long-term survival. By October 2025, 60 patients with early-stage non-gastric MALT lymphoma were enrolled. Among the per-protocol efficacy-evaluable cohort (n = 55), the combined immunoradiotherapy regimen achieved a complete response rate of 100%. At a median follow-up of 30.2 months, only one distant recurrence was observed (estimated 5-year distant recurrence: 1.9%). In the full analysis set, 2- and 4-year progression-free survival rates were 98.0% and 92.9%, respectively, improving to 100% and 94.4% in the per-protocol set. Treatment-related hematologic toxicity was frequent but manageable. Infections were reported in 23.3%, including one grade 4 respiratory infection that necessitated treatment discontinuation. Immunophenotypic profiling revealed that parotid, thyroid, or mediastinal involvement correlated with higher lymphocyte proportions (39.5% ± 16.4%, P = 0.012). Post-treatment immunologic changes featured near-complete B-cell depletion and a compensatory expansion of NK cells. Overall, the combined immunoradiotherapy regimen demonstrated durable disease control in localized non-gastric MALT lymphoma, with potential synergistic benefit from NK cell-mediated immune activation. Trial registration: Chinese Clinical Trials Registry, ChiCTR2000036318; registered on Aug 22, 2020 (prospective).