Biological therapy in Sjögren’s syndrome : outcomes and evaluation

Sjögren’s syndrome, the most common systemic autoimmune disease after rheumatoid arthritis, is characterized by chronic inflammation of the exocrine glands. The salivary and lacrimal glands are commonly affected, resulting in dry mouth and dry eyes. Extraglandular involvement can occur, and includes pulmonary disease, renal disease and vasculitis. Almost all patients suffer from chronic fatigue. Sjögren’s syndrome can be primary or secondary, the latter being associated with other autoimmune diseases such as rheumatoid arthritis and systemic lupus erythematosus. Although there is currently no curative or causal treatment for Sjögren’s syndrome, various supportive and palliative treatment options are available. Biological disease-modifying antirheumatic drugs (DMARDs) have become available over the past decade. These DMARDs target cells and cytokines involved in the pathogenesis of Sjögren’s syndrome, and are considered promising therapies. In this thesis, the impact of having Sjögren’s syndrome on patients’ functioning and daily activity is investigated, the efficacy of 2 biological DMARDs (rituximab, abatacept) is assessed, and the ability of the European League against Rheumatism (EULAR) Sjögren’s Syndrome Disease Activity Index (ESSDAI) and the EULAR Sjögren’s syndrome Patient Reported Index (ESSPRI) to monitor the effect of intervention treatment in primary Sjögren’s syndrome is studied. The key findings of the research presented in this thesis are the major impact of Sjögren’s syndrome on health-related quality of life, employment and disability in these individuals; the observation that ESSDAI and ESSPRI are sensitive instruments for measuring changes in disease activity and the promising efficacy of rituximab and abatacept in the treatment of primary Sjögren’s syndrome.