As Patents Expire, Oncology Biosimilars Poised to Expand, Authors Say

Biologics currently make up half of the pharmacological market for oncology, but the steep cost of these drugs is a barrier to access. By 2023, patents on nearly 20 oncology biologics will expire, which could lead to more biosimilars in cancer care and therefore reduced costs, according to a review article.

Data supporting the effectiveness and safety of biosimilars has accumulated since 2003, when the European Medicines Agency (EMA) launched its biosimilar regulatory and approval process. The FDA began regulating biosimilars in 2009. Both EMA and FDA approve biosimilars demonstrated to have no clinically meaningful differences in purity, safety, and efficacy compared to their respective reference products.

Nonetheless, biosimilars are not identical to their reference products, which has slowed acceptance by physicians and patients. The authors cite previous research suggesting a lack of understanding of and familiarity with biosimilars among oncologists. The authors also note no biosimilar has been approved by the FDA as interchangeable with its reference biologic.

Immunogenicity is a major concern of physicians familiar with biosimilars. The authors acknowledge small changes in the structure of the biologic or a different route of administration could increase the risk of adverse events. They stress the importance of pharmacovigilance and collection of long-term safety data of approved biosimilars to improve physician confidence in biosimilars.

The authors discuss the biologics for which biosimilars are currently approved as treatment or supportive care of cancer in Europe and/or the United States. As of the date the article first published last fall, the authors said:

• A rituximab biosimilar was the first oncology biosimilar approved in Europe. There are now 6 approved in Europe and 2 in the United States.
• The patent on trastuzumab (Herceptin) expired in Europe in 2014. The EMA approved the first trastuzumab biosimilar in 2017 and 4 more in 2018.
• FDA approved biosimilars to bevacizumab in 2017, as did EMA in 2018. The US patent on bevacizumab (Avastin) expired in 2019.
• Nine filgrastim biosimilars have been approved in Europe since 2008 and 2 in the United States.
• There are 5 pefgilgrastrim biosimilars approved In Europe and 2 in the United States.
• Five epoetin biosimilars have been approved in Europe and 1 in the United States.

The authors stress the need to educate physicians and patients about the safety and efficacy of biosimilars and collect long-term safety data to improve their acceptance and promote their use in routine cancer treatment.

Reference

Konstantinidou S, Papaspiliou A, Kokkotou E. Current and future roles of biosimilars in oncology practice. Oncol Lett. 2020;19(1):45—51. doi:10.3892/ol.2019.11105.