Primary Sjögren's syndrome (pSS) is a systemic autoimmune disease with a female-to-male predominance of 9:1 and a peak incidence at 50 years of age. It is characterized by chronic inflammation and subsequent destruction of exocrine glands, mainly lacrimal and salivary glands, with ocular and oral dryness. Patients also experience joint pain and extreme fatigue. In 20-40% of patients, the inflammatory process extends beyond the exocrine glands and patients experience systemic extra glandular manifestations, with 5-10% developing B-cell lymphoma.
Two populations of pSS patients can be defined. Patients with dryness, fatigue, pain and low systemic activity present no or limited long-term extraglandular damage but they have a profoundly reduced quality of life with marked anxiety, depression, and social isolation (Rischmueller 2016)(Meijer, 2009). Patients with high systemic activity have important long-term damage and bad prognosis. To date, there are no approved disease-modifying treatments.
Current clinical outcome assessment (COA) tools in pSS have shown important weaknesses (e.g. high placebo response rate) which may hamper demonstration of therapeutic benefit. A novel COA called STAR has recently been developed by the NECESSITY consortium (funded by the Innovative Medicines Initiative) and should allow the identification of new therapeutic options for both patient populations.
the investigator aim to demonstrate, thanks to the new STAR outcome measure, efficacy of a combination therapy targeting both B- and T-cells in pSS patients.