A randomized, phase II study of sequential belimumab and rituximab in primary Sjögren's syndrome

BACKGROUND: Primary Sjögren’s syndrome (pSS) is characterized by B cell hyperactivity and elevated B-lymphocyte stimulator (BLyS). Anti-BLyS treatment (e.g., belimumab) increases peripheral memory B cells; decreases naive, activated, and plasma B cell subsets; and increases stringency on B cell selection during reconstitution. Anti-CD20 therapeutics (e.g., rituximab) bind and deplete CD20-expressing B cells in circulation but are less effective in depleting tissue-resident CD20(+) B cells. Combined, these 2 mechanisms may achieve synergistic effects. METHODS: This 68-week, phase II, double-blind study (GSK study 201842) randomized 86 adult patients with active pSS to 1 of 4 arms: placebo, s.c. belimumab, i.v. rituximab, or sequential belimumab + rituximab. RESULTS: Overall, 60 patients completed treatment and follow-up until week 68. The incidence of adverse events (AEs) and drug-related AEs was similar across groups. Infections/infestations were the most common AEs, and no serious infections of special interest occurred. Near-complete depletion of minor salivary gland CD20(+) B cells and a greater and more sustained depletion of peripheral CD19(+) B cells were observed with belimumab + rituximab versus monotherapies. With belimumab + rituximab, reconstitution of peripheral B cells occurred, but it was delayed compared with rituximab. At week 68, mean (± standard error) total EULAR Sjögren’s syndrome disease activity index scores decreased from 11.0 (1.17) at baseline to 5.0 (1.27) for belimumab + rituximab and 10.4 (1.36) to 8.6 (1.57) for placebo. CONCLUSION: The safety profile of belimumab + rituximab in pSS was consistent with the monotherapies. Belimumab + rituximab induced enhanced salivary gland B cell depletion relative to the monotherapies, potentially leading to improved clinical outcomes. TRIAL REGISTRATION: ClinicalTrials.gov NCT02631538. FUNDING: Funding was provided by GSK

Autoantibodies in Sjögren's syndrome and its classification criteria

Sjögren's syndrome (SS) is a systemic autoimmune disease characterized by immune-mediated injury of exocrine glands. Extensive lymphocytic infiltrates may contribute to the destruction and loss of secretory function of glands. B-cell hyperactivity is a key feature of the disease resulting in the production of a diverse array of autoantibodies in these patients. Although not specific for SS, anti-Ro/SSA and anti-La/SSB antibodies have been useful biomarkers for disease classification and diagnosis. During recent years, novel autoantibodies have been discovered in SS. In this review, we summarize the historical role and clinical relevance that autoantibodies have played in the classification criteria of Sjögren's syndrome, discuss laboratory aspects in antibody detection and review the role of novel autoantibodies in predicting particular stages of the disease, clinical phenotypes and long-term complications

Het idiopathisch mestcelactivatiesyndroom

BACKGROUND: Idiopathic mast cell activation syndrome (MCAS) is one of the causes for recurrent complaints. The diagnosis is sometimes delayed but also often made incorrectly. CASE: Our patient presented with recurrent attacks of itching, redness of the skin, diarrhea and near collapse. During an attack his serum tryptase level rose significantly. We could not identify an underlying trigger. A diagnosis of idiopathic mast cell activation syndrome was made. He was successfully treated with a combination of H1 and H2 blockade. CONCLUSION: MCAS is characterized by recurrent complaints. To make the diagnosis a significant rise in mast cell mediators is required. Given the diversity of symptoms many patients with somatically unexplained symptoms wrongfully believe to be suffering from MCAS