Low-dose rituximab is efficacious in refractory idiopathic inflammatory myopathies

OBJECTIVES

Rituximab (RTX) use early in the course of refractory idiopathic inflammatory myopathy (IIM) is not well studied. This study sought to determine the short-term efficacy of RTX in a registry-based cohort of refractory IIM.

METHODS

Registry-based observational data about IIM patients receiving RTX between 2018 and 2021 were included. Total improvement score was calculated from the core set measures as per International Myositis Assessment and Clinical Studies group (IMACS) at baseline, 6 months and 12 months of follow-up.

RESULTS

Forty-two patients (F:M, 29:13), with a mean (s.d.) age of 39.5 (11.5) years were studied. Majority of patients received RTX for refractory myositis, after a median (interquartile range) duration of 8 (4,18) months. Twenty-eight received RTX at a dosage of 1 g × two doses, while 14 received 500 mg × two doses with an interval of 15 days. At 6 months and 12 months post-RTX, the improvement was recorded in manual muscle testing (MMT-8) scores, physician global assessment (PGA), patient global assessment (PtGA) and median steroid dosage as compared with the baseline (P < 0.01 for all). A mean (s.d.) improvement of 44.5 (16) and 48.7 (19.2) in total improvement score was recorded at 6 and 12 months, respectively. The change in MMT-8, PGA and PtGA scores from baseline between the two dosage regimens of RTX were comparable at 6 and 12 months. Severe lower respiratory tract infections requiring hospitalization occurred in three patients of the cohort.

CONCLUSION

RTX improved IMACS core set measures and had steroid sparing efficacy at 6 and 12 months in patients with IIM in this registry-based study. Rituximab as an induction regimen of two doses of 500 mg can be as efficacious as 1 g at 6 months and 12 months of follow-up.

Combination of low-dose rituximab, bortezomib and dexamethasone for the treatment of autoimmune hemolytic anemia

Autoimmune hemolytic anemia (AIHA) therapy may be associated with severe complications such as diabetes, hypertension, obesity, osteoporosis, peptic ulcers, infection, and some other diseases. To reduce those effects, we used low-dose rituximab, bortezomib and dexamethasone (LowR-BD regimen) to treat AIHA. The purpose of this study was to evaluate the efficacy and safety of this regimen.Seven patients with warm AIHA (wAIHA) admitted from March 2020 to October 2020 were treated with LowR-BD regimen: Rituximab 100 mg by intravenous infusion on day 1 combined with bortezomib 1.3 mg/m2 by subcutaneous injection on day 2 plus dexamethasone 20 mg by intravenous infusion on days 2, 3. Clinical efficacy and safety were assessed at the regular reexamination of relevant indicators and follow-up.After 4 cycles of the LowR-BD regimen, the overall response rate (ORR) was 85.71% with a complete response (CR) of 28.57% and a partial response (PR) of 57.14%. After a median follow-up of 12 (range 7-13) months, 5 patients achieved CR and 2 patients had PR status, including 1 patient who did not respond to LowR-BD treatment and reached CR after using methylprednisolone combined with cyclophosphamide. One patient relapsed and achieved PR after retreatment of 2 cycles LowR-BD regimen. The patients tolerated the treatment well and did not complain of apparently adverse reactions except a patient with Sjogren's syndrome and bronchiectasis who developed a severe infection during treatment.Low-dose rituximab combined with bortezomib and dexamethasone is effective and relatively safe in patients with wAIHA.

Successful treatment of refractory thrombotic thrombocytopenic purpura associated with systemic lupus erythematosus with combination of plasma exchange and low-dose rituximab

OBJECTIVES

Thrombotic thrombocytopenia purpura (TTP) associated with systemic lupus erythematous (SLE) (i.e., SLE-TTP) is a rare life-threatening disease often requiring intensive immunosuppressive agents, in addition to high-dose corticosteroids and plasma exchange (PEX). The optimal therapy of rituximab is unclear, but 375 mg/m² weekly for 4 weeks is the usual practice, adopted from regimens for non-Hodgkin's lymphoma. We reported two cases of refractory SLE-TTP that showed good efficacy and prognosis with combination of methylprednisolone (MP) pulse, plasma exchange and low-dose rituximab (100 mg weekly for 4 weeks) treatment.

METHODS

Clinical data and treatment outcomes were reviewed of two patients diagnosed with refractory SLE-TTP at Peking Union Medical College Hospital between July 2017 and July 2018.

RESULTS

Both patients had SLE and presented with microangiopathic anemia and thrombocytopenia. Laboratory assays revealed high anti-nuclear antibody titers, reduced complement 3 and 4 levels, proteinuria, significantly elevated lactate dehydrogenase, schistocytes on peripheral blood smear, low ADAMTS13 activity, and the presence of ADAMTS13 inhibitor. In both patients, platelet counts remained below 50 × 10⁹/L after MP pulse and 6 PEXs, confirming the diagnosis of refractory SLE-TTP. Low-dose rituximab (100 mg weekly for 4 weeks) was administered in both cases, resulting in normalization of platelet counts and significant reductions in B-lymphocyte counts. No TTP relapse or SLE flare occurred during 24 months of follow-up.

CONCLUSIONS

Our cases confirmed the efficacy and good follow-up outcomes of low-dose rituximab treatment (100 mg weekly for 4 weeks) for refractory SLE-TTP.

Evans syndrome: clinical perspectives, biological insights and treatment modalities

Evans syndrome (ES) is a rare and chronic autoimmune disease characterized by autoimmune hemolytic anemia and immune thrombocytopenic purpura with a positive direct anti-human globulin test. It is classified as primary and secondary, with the frequency in patients with autoimmune hemolytic anemia being 37%–73%. It predominates in children, mainly due to primary immunodeficiencies or autoimmune lymphoproliferative syndrome. ES during pregnancy is associated with high fetal morbidity, including severe hemolysis and intracranial bleeding with neurological sequelae and death. The clinical presentation can include fatigue, pallor, jaundice and mucosal bleeding, with remissions and exacerbations during the person’s lifetime, and acute manifestations as catastrophic bleeding and massive hemolysis. Recent molecular theories explaining the physiopathology of ES include deficiencies of CTLA-4, LRBA, TPP2 and a decreased CD4/CD8 ratio. As in other autoimmune cytopenias, there is no established evidence-based treatment and steroids are the first-line therapy, with intravenous immunoglobulin administered as a life-saving resource in cases of severe immune thrombocytopenic purpura manifestations. Second-line treatment for refractory ES includes rituximab, mofetil mycophenolate, cyclosporine, vincristine, azathioprine, sirolimus and thrombopoietin receptor agonists. In cases unresponsive to immunosuppressive agents, hematopoietic stem cell transplantation has been successful, although it is necessary to consider its potential serious adverse effects. In conclusion, ES is a disease with a heterogeneous course that remains challenging to patients and physicians, with prospective clinical trials needed to explore potential targeted therapy to achieve an improved long-term response or even a cure.