Biosimilars for breast cancer

ABSTRACT

Introduction: Cancer treatment has evolved significantly with the introduction of biologic agents, especially in the breast cancer (BC) area. The use of trastuzumab for HER2 amplified BCsignificantly improves survival in both metastatic and early stage disease. Although the efficacy of biologics is undeniable, their high costs increased the expenses of cancer care, becoming a problem to health-care systems, mainly in low and middle-income, but also for high-income countries. In an attempt to lower the costs and allow a greater access of biologics to cancer patients, biosimilars are rapidly being developed as an alternative to the reference biologics.

Areas covered: A literature review based on the MEDLINE/PubMed search about biosimilars allied with the FDA and EMA’s latest statements of this topic were conducted to summarize the development and the use of currently available biosimilars for BC, with a focus on trastuzumab.

Expert opinion: Biosimilars are drugs that have similar efficacy and safety profile to those of the original biological product with equivalent immunogenicity and, as these agents hold the potential to improve patient´s access to monoclonal antibodies because their production costs are estimated to be 20–30% lower compared to the reference product, they are progressively being incorporated into clinical practice.

KEYWORDS:

• Biologic agents
• biosimilars
• HER2 amplified breast cancer
• trastuzumab

Article Highlights

• Biosimilars are drugs that have the same efficacy and safety of the original biological product with the advantage that is cheaper than the reference drug;

• In the BCarea, one of the most important drugs for treatment of HER2-overexpressed BCis trastuzumab;

• The high costs of trastuzumab enable its use widespread, not only in low and middle-income countries, but also in high-income countries;

• Until now, there are five trastuzumab´s biosimilars approved in Europe and two in the United States, which can increase the prescription of trastuzumab for BC;

• The confirmatory studies for trastuzumab´s biosimilars have proved they are as safe as the original drug and has the same toxicity profile and immunogenicity, with similar results in terms of efficacy.

This box summarizes the key points contained in the article.

Declaration of interest

G Curigliano is on expert advisory boards for Myla, Samsung, Pfizer, Roche, Novartis, Lilly, Celltrion. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer Disclosures

One of the peer reviews declares that they have received grants from Lilly and Roche for traveling and expert advisory during 2018; this same reviewer has acted as an advisor for Pfizer during 2019. Three additional peer reviewers on this manuscript have no relevant financial relationships or otherwise to disclose.

Additional information

Funding

B Zucchetti acknowledges the support from the European School of Oncology for a Clinical Training in Breast Cancer at the European Institute of Oncology, Milan, Italy.