Biologic drugs are medicines that come from living organisms, like genes and proteins. Biologics make up about 5% of U.S. prescriptions, but more than 50% of total prescription drug spending in the country.
Biosimilar drugs are biologic drugs that are highly similar compared to their reference products, which are existing biologics. Biosimilars are not exact copies of biologics but do share the same or close to the same qualities. There is no clinically meaningful difference between the two.
All biosimilars are not interchangeable with their reference products—those that are interchangeable must meet additional requirements and can be substituted for the reference product at the pharmacy. The Food and Drug Administration (FDA) is the agency responsible for approving biosimilars.
In October 2025, the FDA explored changes to make the biosimilar approval process faster and to make it less expensive to develop biosimilars. The FDA also wanted to make it easier for biosimilars to be considered interchangeable and to reduce unnecessary testing. Europe has eased requirements for biosimilar interchangeability for about 20 years. In September 2022, the European Medicines Agency said that biosimilars approved in the European Union would be considered interchangeable with their reference products.
In March 2026, the FDA issued draft guidance on biosimilars, recommending streamlining unnecessary pharmacokinetic testing when scientifically justified. Pharmacokinetics involves how the body absorbs, distributes, and eliminates a drug.
Below are five myths about biosimilars.
1.Biosimilars are the same as generic drugs. FALSE
- In generic drugs, the active ingredient is identical to that of a small molecule drug. They are usually synthesized from chemicals and have the same dosage, form, safety, route of administration, quality, performance characteristics, and intended use.
- Biosimilar drugs are similar to biologic drugs, which come from living organisms, but are not exact copies. Biologics are generally more complicated to make than drugs composed of chemicals.
- Generics and biosimilars are approved through different pathways through the FDA. Generic drugs are approved through the New Drug Application (NDA) process. Biosimilars are approved through the Biologics License Application (BLA) process.
2. Biosimilars aren’t as safe or effective as their reference products. FALSE
- According to the FDA, biosimilars are just as effective and safe as their reference products. Biosimilars have the same strength and dosage as their reference products.
- An October 2025 article published in the European Journal of Pharmaceutical Sciences also said that biosimilars are effective: “As of 2025, the entirety of the evidence, including pharmacovigilance databases, clinical trials, and structural analysis, consistently shows that biosimilars perform identically to their reference products in every assessed area.”
- A recent study on the effectiveness of biosimilars versus biologics for rheumatoid arthritis showed that biosimilars generally had comparable effectiveness to biologics.
3. Switching from a biologic to a biosimilar is challenging. FALSE
- In recent years, patients, pharmacists, and doctors have become more comfortable with and more knowledgeable about biosimilars. The FDA also has more experience with biosimilars, and the pathway to excluding biosimilars has shrunk.
- From an operational perspective, if a biosimilar is interchangeable, it can be switched at the pharmacy without notifying the doctor if allowed by state law. Biosimilars are also being added more quickly to formularies than in the past.
4. Biosimilars aren’t cost effective. FALSE
- Biosimilars cost less than their reference products. On average, biosimilar drugs cost 50% less than the reference product at the time of the biosimilar launch. Sometimes, biosimilars can cost even less. For example, Imuldosa™, which was approved in October 2024 to treat chronic inflammatory conditions, came on the market at a 92% discount.
- In 2024, biosimilars saved $20.2 billion. And since 2015 when the first biosimilar came on the market, $56.2 billion has been saved.
5. Biosimilars are only approved for less serious conditions. FALSE
- There are biosimilars for serious illnesses, including cancer. For example, Jobevne™ was approved in April 2025 to treat various kinds of cancer, including metastatic colorectal cancer and some types of non-small cell lung cancers. There are about five biosimilars for Herceptin®, which treats some kinds of breast cancer and stomach cancer. And Poherdy® was approved in November 2025 as the first interchangeable biosimilar for Perjeta®, which treats some types of breast cancer.
- Additionally, Tyruko®, a biosimilar for Tysabri®, was approved in 2023 and became available late last year. Tyruko treats multiple sclerosis. There are several biosimilars for Lucentis®, which treats wet age-related macular degeneration, diabetic eye disease, and some retina problems. The most recent approval was for Nufymco® in December 2025.
Biosimilars offer a safe and effective way for patients to save money on prescription spending. As the FDA loosens restrictions on the approval process, they may appear on formularies more frequently, and there may be even greater uptake from consumers.
Interested in learning more about biosimilars? Please contact [email protected].
