AB1171 COMPUTER-BASED EVALUATION OF JOINT SPACE NARROWING IN PATIENTS WITH RHEUMATOID ARTHRITIS TREATED WITH WITH CERTOLIZUMAB PEGOL

Abstract

Background: The reduction of finger joint space width in patients with rheumatoid arthritis (RA) is associated with joint destruction. Anti-TNF treatment with certolizumab pegol is an effective therapy in RA-patients. The computer-assisted joint space analysis is a new computer based technique to measure joint space width on hand radiographs. Objectives: The aim of this post-hoc analysis of the data set used in the RAPID 1 trial was to quantify finger joint space width of RA patients treated with Certolizumab pegol. Methods: The post-hoc analysis includes 328 patients. These patients were divided into three groups: methotrexate plus placebo, certolizumab pegol 200 mg (every two weeks) plus methotrexate, and certolizumab pegol 400 mg (every two weeks) plus methotrexate. All patients underwent x-rays of the hand at baseline and week 52 as well as the quantification of finger joint space width of the metacarpal-phalangeal articulations (MCP) using the computer-assisted joint space analysis (Version 1.3.6; Sectra; Sweden). The joint space distance is expressed as mean joint space width of the MCP joints I to V (JSD-MCP total). Results: The methotrexate group presented a significant joint space reduction with -4.8% for JSD-MCP total from 0.151 ± 0.028 cm (baseline) to 0.144 ± 0.033 cm (week 52). For the patients treated with certolizumab pegol 400 mg a non-significant change (0.6%) of JSD-MCP total from 0.146 ± 0.034 cm (baseline) to 0.147 ± 0.036 cm (week 52) was observed. A similar result was evaluated for the certolizumab pegol 200 mg group (JSD-MCP total: 0.147 ± 0.035 cm [baseline] to 0.147 ± 0.036 cm [week 52]). Conclusion: The study highlights that patients treated with certolizumab pegol plus methotrexat show no change of joint space width of the metacarpal- phalangeal articulations in comparison to patients with methotrexate plus placebo estimated by computer-assisted joint space analysis. Consequently, the automatic quantification of finger joint space is a sensitive technique for the quantification of joint space reduction and treatment monitoring.