Biosimilars in Oncology

The escalating cost of cancer care is placing an increasing burden on healthcare systems worldwide, largely a result of expensive biologic therapies. With the patents on many biologics expiring, interest in biosimilars is rising. Biosimilars of biologic agents used for cancer treatment and supportive care are making their appearance in the US; this article therefore aims to increase understanding of the biosimilars concept. Biosimilars are very comparable to their reference products, but because of their size and complexity, are not identical. However, the inherent structural differences between biologics and their reference products may not translate to clinically meaningful differences in efficacy and safety. Biosimilars offer potential cost savings but present a challenge in terms of establishing a regulatory pathway. Regulatory approval requires comparative analytical and clinical studies in order to characterize and demonstrate the absence of clinically meaningful differences between biosimilars and their reference products. Initial approval may not include interchangeability, as additional evidence may be required before a biosimilar can be designated interchangeable with its reference product. A framework for the approval of biosimilars was established by the European Medicines Agency (EMA) in 2006 with the first biosimilar approved in April, 2006. Thus, the experience in Europe provides valuable insights into the use of biosimilars. The widespread use of biosimilars has the potential to reduce healthcare expenditure, as well as improving patient access without compromising patient outcomes, but clinician education and acceptance is crucial.