A Study to Evaluate the RNA Signature of Rheumatoid Arthritis From Synovium and Whole Blood

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease affecting approximately 1% of the adult population. The disease is characterised by inflammation of synovial tissue (ST) in multiple joints, which often leads to destruction of joint integrity, contributing to serious functional impairment and disability. The contributors to its pathology include joint inflammation, abnormal cellular and humoral responses, and synovial hyperplasia. Ultrasonography is a powerful, non−invasive, and feasible way to evaluate synovial hyperplasia and guide its collection by biopsy.

Although RA is a systemic disease, it is not clear whether the gene expression profile exhibited by circulated peripheral blood cells and that expressed by the inflamed synovium mirror one another. Understanding this relationship would be useful not only in potentially having a relatively non−invasive means to predict response to therapy but it might be useful in better understanding differences in RA expression amongst patients with this disease, thus perhaps assisting in target identification through a better understanding of disease processes.

Adult men and non-pregnant, non-lactating women between 18 and 75 years of age with a clinical history of rheumatoid arthritis.

• A
  12 treatment naive patients who fulfil the ACR criteria for RA with active disease defined by a Disease Activity Score(DAS)28 score of more than 3.2.
• B
  6 RA patients in remission on a stable dose of methotrexate with a DAS28 score lower than 2.6
• C
  12 patients who fulfill the ACR criteria for RA and are being treated with methotrexate but still have active disease, defined as a DAS28 score of more than 3.2

Inclusion criteria

• Adult men and non-pregnant, non-lactating women between 18 and 75 years of age. Sexually active females must be of either non-childbearing potential or willing to comply with the contraceptive requirements
• Body weight greater >40 kg and <120 kg with a body mass index (BMI) between 19-31 kg/m2
• Clinical history of rheumatoid arthritis as defined by ACR criteria
• Negative urine pregnancy test for women of child bearing age (except those with documented proof of hysterectomy or bilateral oophorectomy)

For populations B and C only

• Currently on a stable dosing regimen of methotrexate 7.5 to 25 mg once weekly, as their only DMARD (no changes in dosing regimen for 4 weeks prior to screening).

Exclusion criteria

• History of an acute illness within 2 weeks prior to the study
• History of drug abuse within 2 years
• Donation of blood in excess of 500 mL within 56 days prior to the first dose of study medication

For group A only

• Prior treatment with disease modifying anti-rheumatic agents or biologicals.