Adalimumab biosimilars in Europe: an overview of the clinical evidence

Adalimumab, the first fully humanised monoclonal antibody against tumour necrosis factor alpha (TNF-α), has played a leading role in the revolution brought about by the introduction of biologics, and has received the widest range of indications among TNF-α inhibitors. Post-registration, observational and registry studies of real-life use have largely supported the outcomes seen in registrational clinical trials. With the recent loss of exclusivity for the originator medicinal product in Europe, a number of biosimilar adalimumab molecules have been licensed for use in the same indications as the originator molecule across rheumatology, dermatology, gastroenterology and ophthalmology. Clinicians in these areas first gained experience with biosimilar infliximab, followed by etanercept and rituximab. However, adalimumab is likely to present unique challenges given the numbers of patients treated and the range of biosimilar adalimumab products available. The biosimilar approval pathway has an emphasis on the pre-clinical analytic data in combination with clinical studies conducted to confirm therapeutic equivalence. To date, several adalimumab biosimilars have entered the EU market following successful marketing authorisation applications and recent expiration of originator patent protection. This overview covers the extent of use of adalimumab and summarises the regulatory process involved in the development of biosimilars as well as their use in clinical practice. The authors also discuss clinical data available so far on adalimumab biosimilars and their envisaged impact in the field of immune-mediated inflammatory diseases.