Biological medicines (or “biologics”) are innovative treatments that play an important and increasingly large role in the targeted treatment of a number of life-threatening and disabling disorders, such as cancer or immune-mediated diseases.1

When the patents for original-brand biologics expire, different pharmaceutical companies are allowed to make these medicines, which have become known as biosimilars. A biosimilar matches the reference medicine in terms of its analytical and functional properties, pharmacokinetics, and pharmacodynamics, as well as clinical efficacy, safety, and immunogenicity, based on the results of a comprehensive comparability exercise2,3,4. When considering product and manufacturing process quality, health authorities apply the same high standards to all biological medicines, irrespective of whether they are reference biologics or biosimilars2.

With suitable approaches from different healthcare authorities, biosimilar medicines have the potential to contribute to solving challenges around access to medicines for patients, physicians and payers5

Biosimilars – the results are the same

Think of an original-brand biologic and a biosimilar like an original key and another version that a locksmith makes. Both keys produce the same result, both will fit the same lock and open the same door, even if there are slight differences between the keys.

Biosimilars - the results are the same
Information for Patients

Biological medicines (or “biologics”) are not like medicines such as aspirin or paracetamol, which are made with chemicals. A biological medicine (commonly referred to as a “biologic” or “biopharmaceutical”) is a pharmaceutical drug whose active substance is made by or extracted from living organisms, tissues, or cells6. Scientists choose appropriate cells (animal or human cells are often used) and then modify them so that with skilful manufacturing they can be made to reproduce indefinitely. These cells become “factories” that endlessly produce a particular substance, usually a protein, which targets a specific illness4.

Biologic medicines have revolutionized the management of some of the most hard-to-treat diseases such as cancer, anemia, and autoimmune conditions such as multiple sclerosis, rheumatoid arthritis, psoriasis, and inflammatory bowel disease1.

One of the reasons biological medicines are so effective is that they are tailor-made to interact with specific targets in the body. This increases the potential that they will have the desired effect against the disease they are designed to treat.

A biosimilar is a successor to a biological medicine (known as the “reference medicine”) for which the patent has expired and exclusivity has been lost. Biosimilars have been shown to have equivalent efficacy and comparable safety and immunogenicity. Therefore, physicians and patients can expect the same clinical outcome2,7,4,8-10.

Biosimilars have been shown to have matching efficacy and comparable safety and immunogenicity. Therefore, physicians and patients can expect the same clinical outcome2,7,4,8-11.

All biological medicines are produced by living organisms, and all, be it the biologic reference medicine or the biosimilar, have a certain degree of inherent, natural variability (“microheterogeneity”). Therefore, not even two batches of the same biologic from the same manufacturing process at the same site are 100% identical; there is even variability within a single batch. 2,4,12,13.  Each batch contains a distribution of biological molecules, either synthesized by the host organism or arising during downstream processing. This inherent variability can be detected and monitored using sensitive analytical tools and is tightly controlled during the manufacturing process, with limits and specifications agreed upon with the regulatory authorities to ensure the consistent safety and efficacy of the biologics being produced2,7,14-16.

When considering product and manufacturing process quality, health authorities apply the same high standards to all biological medicines, irrespective of whether they are reference biologics or biosimilars2. Approval of a biosimilar by the EMA (EU) or the US FDA is granted on the “totality of evidence”. This includes the extensive characterization of the reference molecule, to provide a full understanding of its structure–function relationship, and a stepwise comparability exercise with the proposed biosimilar. The comparability exercise involves a large battery of state-of-the-art physico-chemical, structural, and in vitro functional testing (also known as biological function tests), as well as preclinical and clinical studies2,8,11,14,15

Patents on some brands of biological medicines have run out or are reaching the end of their term, which is why different pharmaceutical companies are making biosimilars of these medicines.

In fact, biosimilars have been around for longer than 15 years. The first biosimilar was approved in Australia in 200420* and now biosimilars are in use in highly regulated countries such as those in Europe, as well as Canada, Japan and Australia, and the US21-23. Many more biosimilars are in development globally and so they are likely to play a growing role in patient care5.

  • Cause healthcare providers to reassess existing guidance about use of a particular biologic based on considerations around cost-effectiveness. 
  • Make treatment more affordable for patients in certain countries who co-pay for their medicines.
  • Allow health systems to redirect funds so that more patients can be treated.
  • Allow some healthcare systems to introduce these innovative treatments to their citizens for the first time.
  • Release resources to help healthcare systems keep pace with growing healthcare needs and fund new generations of innovative treatments so that access to treatments, patient care and patients’ lives can all be improved with a sustainable approach.

As with all decisions about managing their condition, patients should talk with their doctor (and healthcare team) about all available treatment options, including their safety, benefits and risks before coming to a decision about the treatment that suits them the best.

Biosimilars’ Benefits for Patients 

Real-life examples

  1. Biosimilars Forum. Partnership for Biosimilars Education and Access. Biosimilars FAQ.2017. Available at:; accessed November 2022.
  2. European Medicines Agency and European Commission. Biosimilars in the EU: Information guide for healthcare professionals. 2019. [Accessed October 2022].
  3. International Alliance of Patients’ Organizations. Briefing Paper on biological and Biosimilar Medicines. November 2013. Available from: [Accessed September 2022]
  4. Kay J. A ‘wind of change’ to biosimilars: the NOR-SWITCH trial and its extension. J Intern Med. 2019;285:693-5.
  5. Institute of Management Services. Delivering on the promise of biosimilar medicines: The role of functioning competitive markets [online]. Available from: [Accessed September 2022].
  6. Heads of Medicines Agencies (HMA). Co-ordination group for mutual recognition and decentralised procedures – human (CMDh). Questions & answers on biologicals, CMDh/269/2012. Rev. 2. 2020. Available at; accessed November 2022.
  7. Weise M, et al. Biosimilars: What clinicians should know. Blood 2012;120:5111–5117.
  8. Cohen HP, et al. Chapter 22: Totality of evidence and the role of clinical studies in establishing biosimilarity. In: Gutka HJ, Yang H, Kakar S. (ed) Biosimilars: regulatory, clinical, and biopharmaceutical development. Springer, 2018.
  9. European Commission (EC). Information guide for patients: what do I need to know about biosimilar medicines. 2017. Available at; accessed November 2022.
  10. McCamish M, et al. Toward interchangeable biologics. Clin Pharmacol Ther. 2015;97:215–7.
  11. McCamish M and Woollett GR. Molecular "sameness" is the key guiding principle for extrapolation to multiple indications. Clin Pharmacol Ther. 2017;101:603–5.
  12. Planinc A, et al. Batch-to-batch N-glycosylation study of infliximab, trastuzumab and bevacizumab, and stability study of bevacizumab. Eur J Hosp Pharm. 2017;24:286–92
  13. Schiestl M, et al. Acceptable changes in quality attributes of glycosylated biopharmaceuticals. Nat Biotechnol. 2011;29:310–12.
  14. Rojas-Chavarro LF and de Mora F. Extrapolation: Experience gained from original biologics. Drug Discov Today. 2021;26:2003–13.
  15. Gerrard TL, et al. Biosimilars: extrapolation of clinical use to other indications. GaBI Journal 2015;4:118–24.
  16. European Medicines Agency (EMA). Guideline on similar biological medicinal products.
  17. CHMP/437/04 Rev 1. Available at; accessed November 2022.
  18. US Food and Drug Administration (FDA). Guidance for industry: scientific considerations in demonstrating biosimilarity to a reference product. 2015. Available at; accessed November 2022.
  19. Kurki P et al. Regulatory evaluation of biosimilars: refinement of principles based on the scientific evidence and clinical experience. BioDrugs. 2022;36:359–71
  20. Australian Government. Department of Health, Therapeutic Goods Administration. Public Summary for Omnitrope® (Somatropin)
  21. World Health Organization. Guidelines on evaluation of similar biotherapeutic products (SBPs) [online] October 2009. Available from: [Accessed: September 2022].
  22. European Medicines Agency. European public assessment reports [online]. Available from: [Accessed: September 2022].
  23. Colwell J. Cancer Discov 2015;5:460

* No specific biosimilar pathway existed at the time in Australia, and so  Omnitrope® was approved under the normal regulatory pathway in 2004. As biosimilar indication had not yet been established, the product was not established as a biosimilar at the time.