Correct Patient Misconceptions Around Biosimilars

As biosimilars become more widely available, there is a growing need to confront the persistent misconceptions that hinder their use. Despite more than a decade of global experience confirming biosimilars’ safety and effectiveness, confusion remains among patients, prescribers, and even some health care professionals. Misconceptions can lead to unnecessary hesitation, increased health care spending, and reduced access to important biologic treatments.

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Biosimilars are biologic products highly similar to an FDA-approved reference product, with no clinically meaningful differences in safety, purity, or potency.¹ Although generics are identical chemical copies of small-molecule drugs, biosimilars are made from living cells, which makes them more complex—but they are just as safe and effective as the original biologic. The approval of a biosimilar requires a rigorous “totality of evidence” approach, including structural and functional characterization, nonclinical evaluations, and clinical data to confirm comparable efficacy and safety.²

Misconceptions About Biosimilars

Biosimilars are the same as generics.

This common misunderstanding can lead to confusion among patients and providers. Although generics and biosimilars offer lower-cost alternatives to brand-name drugs, they are not the same. Generics are exact chemical copies of small-molecule drugs, with identical active ingredients, strengths, dosage forms, and routes of administration. Their development is relatively straightforward, as small-molecule drugs have simple and predictable structures.

Biosimilars, however, are derived from living cells and are much more complex in structure and manufacturing. Given the complexity of biologic medicines, biosimilars are designed to closely match an FDA-approved reference product, ensuring no clinically meaningful differences in safety, purity, or potency.¹ Natural variability can arise from minor differences in cell lines, manufacturing processes, or protein modifications. This often leads to hesitation among clinicians and patients, who may misinterpret “not identical” as meaning “not equally effective or safe.”

Biosimilars are less safe or effective than reference biologics.

It is a common misconception that biosimilars are less safe or effective than their reference biologics. Biosimilars must demonstrate high similarity to their reference products through a comprehensive totality of evidence approach. This includes structural, functional, and clinical data that confirm comparable safety, efficacy, and immunogenicity.^1,3,4 The FDA’s rigorous approval process ensures biosimilars meet the same standards as their reference biologics.¹

Switching from a reference biologic to a biosimilar is risky.

Scientific evidence does not support the belief that switching from a reference biologic to a biosimilar compromises safety or efficacy. A comprehensive review of 90 studies involving more than 14,000 patients demonstrated no increase in adverse events, immunogenicity, or loss of clinical effectiveness following a switch.⁵ Additional evidence from randomized controlled trials, such as the phase 4 interventional NOR-SWITCH study (NCT02148640), confirms that switching to a biosimilar does not impact patient outcomes, showing no significant differences in efficacy or safety compared with the reference biologic.⁶

Biosimilars are only about cost savings.

Biosimilars are often seen primarily as a cost-saving solution, typically priced 15% to 35% lower than reference biologics. However, their benefits extend beyond financial savings.⁷ In 2023, biosimilars contributed to nearly 500 million additional treatment days, improving access to essential therapies for patients who might otherwise go without.⁸ This increased availability is particularly important in underserved populations, where biosimilars can help ensure equitable access to lifesaving treatments.

Biosimilars are not approved for all the same uses.

Biosimilars are often thought to be limited to only a few indications, but this is not the case. Through a scientifically rigorous process called extrapolation, biosimilars can be approved for the same indications as the reference biologic without requiring separate clinical trials for each one. Extrapolation is a well-established regulatory practice supported by agencies such as the FDA and European Medicines Agency, ensuring that biosimilars are safe and effective across multiple conditions.³

Conclusion

Pharmacists stand at the forefront of patient care, making them indispensable in dispelling misinformation that can sometimes surround biosimilars. Their accessibility and expertise perfectly position them to engage in direct conversations with patients, addressing safety, efficacy, and interchangeability concerns. By providing clear, evidence-based explanations and fostering trust, pharmacists empower patients to make informed decisions about their treatment options. This direct engagement is crucial in building confidence in biosimilars and ensuring their appropriate utilization, contributing to more affordable and accessible health care.

REFERENCES

1. Nine things to know about biosimilars and interchangeable biosimilars. FDA. Updated June 20, 2024. Accessed May 13, 2025. https://www.fda.gov/drugs/things-know-about/9-things-know-about-biosimilars-and-interchangeable-biosimilars

2. Biosimilar medicines: overview. European Medicines Agency. Accessed May 13, 2025. https://www.ema.europa.eu/en/human-regulatory-overview/biosimilar-medicines-overview

3. US Department of Health and Human Services; FDA; Center for Drug Evaluation and Research; Center for Biologics Evaluation and Research. Scientific Considerations in Demonstrating Biosimilarity to a Reference Product: Guidance for Industry. April 2015. Accessed May 13, 2025. https://www.fda.gov/media/82647/download

4. McClellan JE, Conlon HD, Bolt MW, et al. The ‘totality-of-the-evidence’ approach in the development of PF-06438179/GP1111, an infliximab biosimilar, and in support of its use in all indications of the reference product. Therap Adv Gastroenterol. 2019;12:1756284819852535. doi:10.1177/1756284819852535

5. Cohen HP, Blauvelt A, Rifkin RM, Danese S, Gokhale SB, Woollett G. Switching reference medicines to biosimilars: a systematic literature review of clinical outcomes. Drugs. 2018;78(4):463-478. doi:10.1007/s40265-018-0881-y

6. Jørgensen KK, Olsen IC, Goll GL, et al; NOR-SWITCH study group. Switching from originator infliximab to biosimilar CT-P13 compared with maintained treatment with originator infliximab (NOR-SWITCH): a 52-week, randomised, double-blind, non-inferiority trial. Lancet. 2017;389(10086):2304-2316. doi:10.1016/S0140-6736(17)30068-5

7. Feng K, Russo M, Maini L, Kesselheim AS, Rome BN. Patient out-of-pocket costs for biologic drugs after biosimilar competition. JAMA Health Forum. 2024;5(3):e235429. doi:10.1001/jamahealthforum.2023.5429

8. 2024 US Generic & Biosimilar Medicines Savings Report. Biosimilars Council. September 2024. Accessed May 13, 2025. https://biosimilarscouncil.org/resource/2024-us-generic-biosimilar-savings-report/