Biomarkers predict long-term outcomes in juvenile idiopathic arthritis

(Press-News.org) Data presented today at the European League Against Rheumatism Annual Congress (EULAR 2014) demonstrate the possibility of using biomarkers (developed from whole blood gene expression profiles) in children with juvenile idiopathic arthritis (JIA) to predict the status of their disease at 12 months. The long-term disease status at 12 months was accurately predicted only after treatment had been initiated, in newly diagnosed patients.1

JIA is the most common childhood* chronic rheumatic disease,2 affecting 16-150 children in every 100,000. As indicated by the name, the cause of JIA is largely unknown.3

"By predicting disease progression in these young children we can better understand the course of the disease and how best to treat the individual," said lead author of the study Professor James Jarvis, from the Department of Paediatrics, University at Buffalo, Buffalo, New York.

Blood gene expression profiling has led to major advances in the field of rheumatology over the last decade but to date it has only been possible to predict therapeutic outcome at 6 months.4

"The challenge was to test the feasibility of using these prognostic biomarkers from whole blood gene expression profiles in children with newly diagnosed JIA to predict disease status at one year," explained Professor Jarvis. "Baseline expression profiles that could predict disease status at six months could not predict status at 12 months. However, using four month data (the earliest point at which samples were collected from children on treatment) we were able to determine strong predictive properties for disease status at 12 months. Thus, after children had initiated therapy longer term outcome was predictable," Professor Jarvis said.

In this study, researchers also discovered the appearance of different mechanisms of response in Rheumatoid Factor (RF) positive† and RF negative patients after four months of therapy, a finding that could explain the relative refractoriness of RF positive patients to otherwise effective therapies.

Whole blood expression profiles were studied from children enrolled in the TREAT study, an NIH‡-funded clinical trial comparing methotrexate (MTX) with MTX + etanercept in children with newly-diagnosed JIA. Gene expression profiles were examined to determine those genes whose expression levels best predicted outcome (active vs. inactive disease) at 12 months.

Researchers have described seven types of JIA, which are distinguished by their signs and symptoms, the number of joints affected, the results of laboratory tests, and the family history.3 In general, symptoms include joint pain, swelling, tenderness and stiffness that last for more than six continuous weeks; the condition can also affect the eyes and lymph nodes.3

INFORMATION: Abstract Number: OP0187

NOTES TO EDITORS: For further information on this study, or to request an interview with the study lead, please contact us via: EULAR congress Press Office: Room 104, Palais des congrès de Paris Email: eularpressoffice@cohnwolfe.com Onsite tel: +44 (0) 7880 173209 Twitter: @EULAR_Press

About EULAR The European League Against Rheumatism (EULAR) is an umbrella organisation which represents scientific societies, health professional associations and organisations for people with rheumatic diseases throughout Europe.

EULAR aims to promote, stimulate and support the research, prevention, and treatment of rheumatic diseases and the rehabilitation of those it affects. With 45 scientific member societies, 35 People with Arthritis and Rheumatism in Europe (PARE) organisations, 17 health professionals associations and 26 corporate members, EULAR highlights the importance of combating rheumatic diseases through both medical means and patient care.

EULAR 2014 is set to be the biggest rheumatology event in Europe with almost 14,000 scientists, physicians, allied health professionals and related audiences in attendance from 130 countries. Over the course of the congress there will be 302 oral and 1,806 poster abstract presentations, 155 sessions, 725 lectures, 33 poster tours with 421 invited speakers. To find out more about the activities of EULAR, visit: http://www.eular.org

1 Yao J, Jiang K, Franks MB et al. Developing prognostic biomarkers from whole blood expression profiling in Juvenile Idiopathic Arthritis: Influence of early therapy on treatment outcome. EULAR 2014; Paris: OP0187 2 Ravelli A, Martini A. Juvenile idiopathic arthritis. Lancet 2007;369:767 3 National Institute of Arthritis and Musculoskeletal and Skin Diseases. What Is Juvenile Idiopathic Arthritis? http://www.niams.nih.gov/Health_Info/Juv_Arthritis/default.asp#2 [Accessed 05/06/2014] 4 Jiang K, Sawle AD, Barton Frank M, et al. Whole blood gene expression profiling predicts therapeutic response at six months in patients with polyarticular juvenile idiopathic arthritis. Arthritis Rheumatol 2014; 66 (5): 1363-71

* Under the age of 16 †Rheumatoid factor is an autoantibody produced in large amounts in adults with rheumatoid arthritis, which may also rarely be detected in children with JIA ‡National Institutes of Health