Analysis of remission in abacept-treated patients with rheumatoid arthritis

This study investigated various remission parameters in rheumatoid arthritis (RA) patients treated with abatacept (Orencia) plus methotrexate (Trexall).

In RA, the immune system begins attacking healthy tissues the way it normally attacks viruses or bacteria. This can cause inflammation, leading to chronic pain. The goal of RA therapy is to achieve remission (reduction of symptoms) or low disease activity (LDA) for as long as possible. There are different scoring systems and criteria to measure RA remission. Disease activity score 28 (DAS28) is the most frequently used scoring system. It is an assessment that measures the progress and improvement of RA by examining 28 joints.

American College of Rheumatology (ACR)-European League Against Rheumatism (EULAR) recommends using more strict remission criteria. These are simplified disease activity index (SDAI), clinical disease activity index (CDAI) and Boolean remission (combination of several scores), among others.

Abatacept is an effective biological disease-modifying antirheumatic drug (DMARD). It remains to be seen whether combination of abatacept with methotrexate, a synthetic DMARD, helps to achieve RA remission faster according to ACR-EULAR criteria.

The authors aimed to assess remissions in RA patients treated with abatacept and methotrexate according to the DAS28 and stricter ACR-EULAR criteria. The authors also aimed to determine the relationship between remission and function.

419 patients with RA were included in this study. Patients were not previously treated with methotrexate or were treated for less than 3 months at a low dose.  210 patients were randomly assigned to receive methotrexate plus abatacept (group 1). 209 patients were randomly assigned to receive methotrexate alone (group 2). All patients received treatments for 12 months.

At 12 months remission rates based on DAS28, SDAI, CDAI and Boolean remission were measured. Rates were consistently higher in group 1 compared to group 2. The DAS28 rate was 47.6% in group 1 compared to 27.3% in group 2. The SDAI was 33.3% in group 1 and 12.4% in group 2. Remission rates in group 1 were 18% higher using both the CDAI and Boolean measures compared to group 2. 

23.3% of patients in group 1 achieved remission for a longer period of time over 0-6 months based on SDAI . This was compared to 12.9% of patients in group 2. Patients who achieved SDAI remission at 3 months were evaluated by a questionnaire-based disability assessment score. The average score was lower for patients in group 1 than for patients in group 2. For patients with moderate to high RA at 3 months, progression in structural damage in joints was less in group 1 patients compared to group 2 patients.

The authors concluded that a high percentage of RA patients reached remission even using strict criteria. The authors also conlcuded that patients treated with abatacept plus methotrexate reached effective and early remission along with long-term benefits.