Biosimilars in Breast Cancer

Breast cancer is a significant health concern globally, leading to maximum mortalities amongst women worldwide, which is 11.6% of all cancers accounting for 2.3 million cases. The commonly used treatments for breast cancer include chemotherapy, surgery, and also radiotherapy. The selection of the treatment relies on various factors, including the disease’s grade, stage, and molecular subtype. This ensures that the treatment is tailored to be effective and secure. Targeted or personalised therapies are the results of cutting-edge cancer treatments that have been made possible by significant advancements in our understanding of cancer biology. In the past 20 years, the biologics, also known as the biologic drugs, have become an essential and valuable tool in treating diseases such as cancer and other therapeutic areas. In the field of breast cancer treatment, biosimilars have been approved for use in both the disease itself and as supportive drugs for cancer patients. The reduction in the treatment cost using trastuzumab biosimilars is approximately 20–30% lower in comparison to the costs using the reference product. The supportive drugs include haematopoietic growth factors like erythropoietin and filgrastim. These drugs are used to manage the patients clinically. The impact of biosimilars on reducing healthcare budgets relies on their acceptance by regulatory agencies, prescribers, chemists, and patients. So far, there have been no significant differences in terms of effectiveness, safety, and immune response between the original product and the biosimilar version. The present chapter focuses mainly the use of biosimilars in breast cancer with the target-based mechanisms and its clinical implications.