In 1985 and 1988 a positive effect of treatment of primary Sjögren's syndrome with hydroxychloroquine was reported in two small open studies. To investigate further the clinical and laboratory effects of hydroxychloroquine in primary Sjögren's syndrome a two year study was performed.
The design of the study included a prospective, placebo controlled, two year double blind crossover trial in 19 patients.
A significant decrease in IgG and IgM and a tendency for a decrease in the erythrocyte sedimentation rate (ESR) during treatment with hydroxychloroquine compared with treatment with placebo were found. No beneficial clinical effect of the use of hydroxychloroquine as expressed in preference for treatment with hydroxychloroquine or placebo with regard to symptoms and signs of primary Sjögren's syndrome could be shown, however, nor any relevant change in tear gland activity and sequelae of peripheral tear function deficiency, nor salivary gland scintigraphy.
The use of hydroxychloroquine at a dose of 400 mg daily taken over a 12 month period does not have a worthwhile clinical benefit in patients with primary Sjögren's syndrome despite an improvement of hyperglobulinaemia and slight changes in the ESR and IgM.