Biological agents, including TNF inhibitors, have revolutionized the treatment of RA in recent years. Certolizumab pegol (CZP) is a novel pegylated anti-TNF approved for the treatment of adult patients with moderately to severely active RA. This article provides an overview of three published clinical trials of CZP in RA in patients with active disease who have shown an inadequate response to DMARDs, including MTX: RA prevention of structural damage (RAPID) 1 and 2, which evaluated the efficacy and safety of CZP added to MTX when dosed every 2 weeks, and efficacy and safety of CZP - 4 weekly dosage in rheumatoid arthritis (FAST4WARD), which evaluated CZP monotherapy when dosed every 4 weeks. In the trials, CZP plus MTX or as monotherapy significantly improved the signs and symptoms of RA and RA disease activity, and CZP plus MTX significantly inhibited the progression of radiographic joint damage as early as Week 16 of the treatment. In addition, CZP treatment significantly improved patient-reported outcome measures, providing significant reductions in pain and fatigue and improvements in physical function as early as Week 1 of treatment; improvements in health-related quality of life were evident at the first assessment at Week 12. CZP treatment improved productivity at work, significantly reducing the number of days of missed work as well as the number of days with reduced productivity, and also increased productivity within the home and improved participation in family, social and leisure activities. CZP was generally well tolerated when used either as monotherapy or added to MTX; most adverse events were mild or moderate. Taken together, the results of these trials suggest that CZP is an effective new option for the treatment of RA.