Abatacept for Rheumatoid Arthritis Refractory to Tumor Necrosis Factor α Inhibition

A substantial number of patients with rheumatoid arthritis have an inadequate or unsustained response to tumor necrosis factor alpha (TNF-alpha) inhibitors. We conducted a randomized, double-blind, phase 3 trial to evaluate the efficacy and safety of abatacept, a selective costimulation modulator, in patients with active rheumatoid arthritis and an inadequate response to at least three months of anti-TNF-alpha therapy.

Patients with active rheumatoid arthritis and an inadequate response to anti-TNF-alpha therapy were randomly assigned in a 2:1 ratio to receive abatacept or placebo on days 1, 15, and 29 and every 28 days thereafter for 6 months, in addition to at least one disease-modifying antirheumatic drug. Patients discontinued anti-TNF-alpha therapy before randomization. The rates of American College of Rheumatology (ACR) 20 responses (indicating a clinical improvement of 20 percent or greater) and improvement in functional disability, as reflected by scores for the Health Assessment Questionnaire (HAQ) disability index, were assessed.