Abatacept treatment reduces disease activity in early primary Sjögren's syndrome (open-label proof of concept ASAP study).

Objective: To assess the efficacy and safety of abatacept in patients with early and active primary Sjögren's syndrome (pSS).

Methods: All 15 patients (12 women, three men) included in the open-label Active Sjögren Abatacept Pilot study met the revised American-European Consensus Group criteria for pSS and were biological disease-modifying antirheumatic drug-naive. Patients were treated with eight intravenous abatacept infusions on days 1, 15 and 29 and every 4 weeks thereafter.