INTRODUCTION: Improved understanding of the pathogenesis of rheumatoid arthritis 
(RA), and subsequent development of targeted therapies, have greatly advanced 
the management of this chronic inflammatory disease. The aim of treatment is a 
state of clinical remission. Certolizumab pegol (CZP) is a novel pegylated TNF 
alpha inhibitor (TNFi) therapy and is the focus of this review.
AREAS COVERED: CZP is different from other TNFi as it contains a polyethylene 
glycol (PEG) moiety, and lacks the constant fragment (Fc) of immunoglobulin; 
therefore it does not activate complement. In this review in addition to 
clinical efficacy of CZP, effects on radiographic and patient-reported outcomes, 
are discussed. Adverse event data from clinical trials and extension studies are 
also reviewed.
EXPERT OPINION: The addition of novel TNFi therapies to treat RA is welcomed. As 
well as displaying clinical efficacy, there is evidence to suggest that CZP has 
unique characteristics, including reduced transfer across the placenta and 
reduced frequency of injection site reactions. Furthermore, randomised 
controlled trials (RCTs) of CZP have demonstrated rapid improvements in 
workplace and home productivity in patients contributing to reducing the 
significant socioeconomic burden of RA.