The Australian Arthritis and Autoimmune Biobank Collaborative (A3BC): a national study collecting broad data and biological samples from individuals with arthritis and autoimmune diseases for research towards safer, more effective and evidence-based prevention, diagnosis, treatment and outcome strategies.

Multi-centre prospective cohort of case and control biospecimens (Biobank) linked to longitudinal personal, patient-reported, clinical and health information (Registry). Biospecimens are collected at 0, 6, 12 and 24 months, with some ad hoc collections. Data are collected 6-monthly up to 24 months, then yearly afterwards for the life of the project – at least 20 years (open-ended). The questionnaires gather information on disease status, quality of life, function, medication history, medical illnesses, malignancy history, infections, lifestyle, diet and environmental/exposure history. Valid and reliable quality of life/function instruments are used. Participants’ health records are also accessed periodically through record linkage with federal/state health services and registries via Services Australia and the Australian Institute of Health and Welfare (National Health Data Hub). Participation is flexible and participants may opt in or out of parts of the study if they wish e.g. registry-only participation. Target cohorts include: At-Risk Cohort Purpose: Identify predictors and mechanisms of disease onset in people at high risk of developing inflammatory arthritis or autoimmune disease. Eligibility: • No confirmed inflammatory arthritis or autoimmune disease, but presence of disease-associated risk factors, such as: o Clinically suspect arthralgia (CSA) of less than 1 year duration, with MCP involvement and greater than 60 minutes of morning stiffness. o Family history of autoimmune or inflammatory arthritis (e.g. first-degree relatives of RA patients) o Presence of RA-associated autoantibodies (e.g. ACPA, RF) in asymptomatic individuals • Suitable for prospective monitoring and biospecimen collection to capture disease transition if/when it occurs Early Disease Cohort Purpose: Understand the earliest stages of inflammatory arthritis and autoimmune disease to inform personalised early treatment and prevention of progression. Eligibility: • Symptom onset within the past 12 months with diagnosed or undifferentiated inflammatory arthritis or autoimmune disease (refer to disease Eligibility Criteria). Starting DMARDs Cohort Purpose: Predict initial treatment response and inform early treatment decisions. Eligibility: • Active inflammatory arthritis or autoimmune disease (see disease Eligibility Criteria) • About to start a new DMARD for the first time or add a new DMARD to an existing regimen • Baseline biospecimens ideally collected prior to any systemic glucocorticoids (IV/IM/PO) or start of new DMARD/s (only NSAIDs and simple analgesics permitted) Switching DMARDs Cohort Purpose: Understand reasons for treatment failure and predict response to subsequent therapies. Eligibility: • Active inflammatory arthritis or autoimmune disease (see disease Eligibility Criteria) • Switching from one DMARD to another due to: o Lack of efficacy o Intolerable side effects or safety concerns o Disease relapse or flare on current regimen • Includes changes between csDMARDs and/or b/tsDMARDs Genetically Driven Disease Cohort Purpose: Explore the genetic factors underlying severe rheumatic diseases and their influence on disease progression and treatment response. Eligibility: • High suspicion of genetic contribution to the disease (see disease Eligibility Criteria) • Participants with severe manifestations of disease that are potentially linked to genetic factors • Conditions could include rare or extreme disease forms where genetic studies are critical for understanding disease mechanisms Difficult-to-treat (D2T) Disease Cohort Purpose: Identify factors that contribute to difficult-to-treat rheumatic diseases and explore management strategies for these patients. Eligibility: • Diagnosis of severe, active, and difficult-to-control inflammatory arthritis or systemic disease (see disease Eligibility Criteria) • Fulfills at least one of the following: EULAR definition of difficult-to-treat RA : 1) Failure of 2 or more b/tsDMARDs (with different mechanisms of action) after failing csDMARDs (unless contraindicated) 2) Presence of at least one of the following: o At least moderate disease activity o Signs and/or symptoms suggestive of active disease o Inability to taper glucocorticoid treatment o Rapid radiographic progression o RA symptoms that reduce quality of life 3) Management of disease symptoms is perceived as problematic by the rheumatologist and/or the patient • Could also include systemic inflammation with poorly controlled disease (e.g. autoimmune diseases like vasculitis, PMR, or others) Stopping DMARDs cohort Purpose: Predict who can sustain disease control/remission after abruptly stopping therapy. Eligibility: • Well-controlled inflammatory arthritis or autoimmune disease using established definitions of remission/low disease activity/clinically inactive disease (see disease Eligibility Criteria). • Participant will be abruptly stopping DMARD therapy as part of routine care. Tapering DMARDs cohort Purpose: Predict who can sustain disease control/remission after tapering therapy. Eligibility: • Well-controlled inflammatory arthritis or autoimmune disease using established definitions of remission/low disease activity/clinically inactive disease (see disease Eligibility Criteria). • Participant will be tapering DMARD therapy as part of routine care, including tapering towards eventual stopping Stable Disease Cohort Purpose: Enable studies of stable rheumatic disease states Eligibility: • Stable inflammatory arthritis or autoimmune disease, typically in remission or low-disease activity, with no plans for changes in treatment regimen at the time of enrolment (see disease Eligibility Criteria).