Project Summary/Abstract: Childhood Sjögren's disease (cSD) is a rare autoimmune disease that primarily affects the glands, leading to salivary and lacrimal gland inflammation that results in reduced function and dryness symptoms. Active inflammation of the salivary glands is one of the most common symptoms in children with cSD. Despite the profound impact on affected children and their families, there is no pediatric-specific clinical trials to inform therapeutic strategies in cSD. Although symptomatic episodes of inflammation to the glands are critical to evaluate drug therapies, how to determine whether a patient has experienced a flare is lacking. There are no widely accepted cSD outcome measures to tell us whether a treatment is effective, especially with regards to flares involving the glands. New medications have the potential to be safe and effective treatments for cSD but they must be evaluated in trials. We propose a novel trial design known as N-of-1 trials to evaluate cSD therapies. N-of-1 trials is a personalized treatment strategy based on the individual patient's response. The goal of this grant will be to successfully finalize a rigorous and impactful clinical N-of-1 trial in cSD. We will accomplish this through three aims. We will develop patient- and parent-driven outcome measures for the evaluation of glandular inflammation and its flares, and their impact on quality of life and mental health for cSD clinical trials. The overall approach for this aim is based off frameworks successfully used previously in pediatric rheumatology. To reach consensus on cSD flare criteria and to develop patient-important cSD outcome measures, we will review the literature, conduct interviews, perform online surveys, and plan a final group meeting, of stakeholders including patients, health professionals, and methodologists. We will prepare and finalize the details for N-of-1 trials in cSD using two therapies. To accomplish this aim our team will develop a study protocol with patient involvement on critical steps of the trials such as the final choice of medications or outcome measures. We will establish a collaborative network of pediatric rheumatology centers for participation in the N-of-1 trial that we will test as a model for current and future studies in cSD.