Objective: There is no effective treatment for patients with primary Sjögren's syndrome (SS). Since tumor necrosis factor alpha (TNF alpha) could be a key element in the pathogenesis of primary SS, we conducted a multicenter, randomized, double-blind, placebo-controlled trial to evaluate the effect of infliximab in primary SS.

Methods: A total of 103 patients with primary SS were randomly assigned to receive infliximab infusions (5 mg/kg) or placebo at weeks 0, 2, and 6 and were followed up for 22 weeks. All patients fulfilled the new American-European Consensus Group criteria for SS and had active disease as assessed by values >50 mm on 2 of 3 visual analog scales (VAS) (0-100 mm) that evaluated joint pain, fatigue, and buccal, ocular, skin, vaginal, or bronchial dryness. A favorable overall response was defined as the patient having > or =30% improvement between weeks 0 and 10 in the values on 2 of the 3 VAS. Secondary end points were values on each VAS separately, the number of tender and swollen joints, the basal salivary flow rate, results of the Schirmer test for lacrimal gland function, the focus score on labial salivary gland biopsy, the level of C-reactive protein, and the erythrocyte sedimentation rate evaluated at weeks 0, 10, and 22, as well as quality of life evaluated by use of the generic Short Form 36 questionnaire administered at weeks 0, 10, and 22.

Results: At week 10, 26.5% of patients receiving placebo and 27.8% of patients treated with infliximab had a favorable overall response (P = 0.89), and at week 22, 20.4% of the placebo group and 16.7% of the infliximab group had a favorable response (P = 0.62). In addition, the 2 groups did not differ in any of the secondary end points over the 22 weeks of the trial. Severe adverse events reported in the infliximab group did not differ from those observed in previous studies.

Conclusion: This randomized, double-blind, placebo-controlled study of an anti-TNF agent did not show any evidence of efficacy of infliximab in primary SS.