Leflunomide-hydroxychloroquine combination therapy in patients with primary Sjögren's syndrome (RepurpSS-I): a placebo-controlled, double-blinded, randomised clinical trial.

Background: Primary Sjögren's syndrome is a systemic autoimmune disease characterised by secretory gland dysfunction, for which no effective therapy is available. Based on the complementary properties of leflunomide and hydroxychloroquine in inhibiting activation of key immune cells in primary Sjögren's syndrome, we aimed to evaluate the clinical efficacy and safety of leflunomide-hydroxychloroquine combination therapy in patients with primary Sjögren's syndrome.

Methods: We did a placebo-controlled, double-blinded, phase 2A randomised clinical trial in patients with primary Sjögren's syndrome at the University Medical Center Utrecht (Utrecht, Netherlands).