Pijpe J et al. (2005) Rituximab treatment in patients with primary Sjögren's syndrome. Arthritis Rheum 52: 2740–2750

There are currently no evidence-based treatments for Sjögren's syndrome (SS), an autoimmune disease characterized by chronic inflammation of the salivary and lacrimal glands that leads to malignant B-cell lymphoma in 5% of patients. Salivary gland function attenuates early in the disease, accompanied by altered salivary composition. Although associated with side effects and the production of antichimeric antibodies, the anti-CD20 monoclonal antibody rituximab has shown promise in the treatment of SS in this small, open-label, phase II study.

Four rituximab infusions were given at weekly intervals to eight patients with early primary SS and seven patients with both primary SS and mucosa-associated lymphoid tissue type (MALT) lymphoma, with the aim of depleting B cells and thereby reducing disease severity. Three early-SS patients did not complete the protocol, owing to antichimeric antibody production and serum-sickness-like symptoms, which are rarely described in the rituximab literature.

In patients with residual stimulated salivary production >0.10 ml/min (all early-SS patients and two with MALT lymphoma), treatment resulted in a significant increase in stimulated salivary secretion, persisting for up to 48 weeks in three patients. Three patients with MALT lymphoma achieved remission, and subjective factors including mouth dryness and physical functioning improved in the early-SS group.

The authors conclude that early treatment with rituximab might prevent irreversible damage to the salivary glands, with regeneration indicated by increased stimulated salivation and reduced salivary sodium concentration; however, the observed side effects warrant further study.