Biosimilars in Rheumatology: General Issues

The biological market is constantly growing. These drugs have experienced huge advances in very different diseases such as rheumatoid arthritis (RA), diabetes or cancer and it is hoped that they will continue doing so. Although such benefits also come with increased treatment costs, therefore challenging the access and sustainability of health systems. When biologicals licenses have expired, the biosimilars appear, bringing lower prices and thus greater access to health services. Nowadays the biosimilar market is small, representing in 2010 a 3% with respect of the sales of the product reference (somatotropin, epoetin and filgrastim) and a 0.7% of the pharmaceutical market [1]. However, following patent expiry of drugs such as infliximab, adalinumab, etanercept, rituximab, cetuximab, trastuzumab or bevacizumab, the biosimilar market will be enhanced. In Europe is expected that biosimilars cut prices by 20-30% in comparison with the reference products, which will also reduce its price in order to remain competitive, as has already happened with filgrastim or epoetin, whose prices have dropped by 40% in the last few years [2]. What is a biosimilar?