Lack of adverse effect of anti-tumor necrosis factor-α biologics in treatment of rheumatoid arthritis: 5 years follow-up

Abstract

Background: Rheumatoid arthritis (RA) is a chronic, systemic inflammatory disorder affecting synovial joints and many other organs. Most patients seen in clinical settings have a progressive chronic disease, with radiographic damage, frequent work disability, incremental functional declines and increased mortality rates. The introduction of the biological drugs in treatment of RA has played an important role in prevention of destructive effects of the disease but may have serious adverse effects due to their powerful inhibition of the immune system.

Objectives: To study the adverse effects (ADEs) of three different tumor necrosis factor α inhibitor (TNFi) drugs (infliximab, adalimumab and etanercept) in RA patients for 5 years in the south-west area of Saudi Arabia.

Methods: Two groups of RA patients were included in this study: The first group included 112 patients, representing the biologics group. These patients received biological therapy plus disease modifying anti-rheumatic drugs (DMARDs): 56 patients received infliximab (IFX), 36 patients received adalimumab (ADL) and 20 patients received etanercept (ETN). The second group also included 112 patients, representing the control group: RA patients treated only with the traditional DMARDs. ADEs were classified into mild and severe.

Results: The mild ADEs which had been recorded during 5 years of follow-up in patients receiving TNFi, were onycholysis (1.8%), positive tuberculin test (1.8%) and small vessel vasculitis (1.8%). Statistically, there were insignificant differences in the mild ADEs except for upper respiratory tract infection that was significantly higher in the control group. Severe ADEs included pneumonia (1.8%) and solid tumor (1.8%) and there were no significant differences between the biologics and control groups. Also there were no significant statistical differences for the ADEs, mild or severe, between the three biologics, infliximab, adalimumab and etanercept. Occurrence of ADEs did not correlate to methotrexate dose, steroid dose or rheumatoid factor positivity.

Conclusions: Our results indicate that the use of TNFi therapy appeared to be as safe as traditional DMARDs in treatment of rheumatoid arthritis patients and long-term follow-up with careful examination is essential to pick up any abnormal ADEs.