What is a biosimilar medication?

A biosimilar is a biologic medication. It is highly similar to a biologic medication already approved by FDA – the original biologic (also called the reference product).

Biosimilars also have no clinically meaningful differences from the reference product. This means you can expect the same safety and effectiveness from the biosimilar over the course of treatment as you would the reference product.

Biosimilars are made from the same types of sources (e.g., living cells or microorganisms) and are just as safe and effective as their reference products.

What are biologic medications?

Biological products (also called biologics) can be made of sugars, proteins, living cells, tissues, or a combination of these. They are made from natural and living sources like animal and plant cells, and microorganisms such as bacteria or yeast.

Biological medications are usually more complex than other drugs. They are often more complicated to purify, process, and manufacture.

A biosimilar is very similar, but not identical, to an original biologic medication.

For biosimilars to be approved by FDA, studies must show that there are no differences in the safety and effectiveness of biosimilars and the original biologics.

Both a biosimilar and its original biologic:

• Are made from the same types of sources (e.g., living sources).
• Provide the same benefits when treating diseases or medical conditions.
• Are given at the same strength and dosage.
• Are not expected to cause new or worsening side effects.

Is your medication available as a biosimilar?

As with all treatment decisions, you should talk to your healthcare providers and check other trusted sources of information related to your specific condition to learn more about biosimilar treatment options.

Biosimilars: what patients need to know

• A biosimilar and its original biologic are made from the same types of sources – and have the same treatment risks and benefits.
• Biosimilars are a type of biologic medication that is safe and effective for treating many illnesses.
• A biosimilar and its original biologic have the same treatment risks and benefits.
• Biosimilars may be available at a lower cost than the original biologics.

The U.S. Food and Drug Administration has approved biosimilar medications to treat conditions such as cancer, diabetes, Crohn’s disease, colitis, rheumatoid arthritis, psoriasis, and more.

But what are biosimilar and interchangeable biosimilar biological medications? To answer that question, it helps to first know what biological products (biologics) are.

Biologics: Medications from Living Organisms

Biologics include medicines that generally come from living organisms, which can include animal cells and microorganisms, such as yeast and bacteria. That makes biologics different from conventional medications, which are commonly made from chemicals.

Unlike conventional medications, biologics generally cannot be made by following a chemical “recipe.” Because biologics generally come from living organisms, their nature varies, and their structures are generally more complex. Thus, developing biologics can be a more complicated process than manufacturing conventional drugs.

A biosimilar is a biologic that is highly similar to, and has no clinically meaningful differences from, another biologic that’s already FDA-approved (referred to as the reference product or original biologic). This means biosimilars:

• Are given the same way (same route of administration).
• Have the same strength and dosage form.
• Have the same potential side effects.

Biosimilars provide the same potential treatment benefits as the original biologic and are generally made with the same types of natural sources as the reference product.

Biosimilars Are Safe and Effective

Biosimilars are as safe and effective as the original biologic; both are rigorously and thoroughly evaluated by the FDA before approval. Before approving a biosimilar, FDA experts must conclude it is highly similar to and has no clinically meaningful differences from the original biologic. The FDA’s thorough evaluation ensures that all biosimilar products are as safe and effective as their reference products and meet the FDA’s high standards for approval. This means you can expect the same safety and effectiveness from the biosimilar over the course of treatment as you would from the original product.

In addition, the FDA closely regulates the manufacturing of biosimilars. The same quality manufacturing standards that apply to the original biologic also apply to the biosimilar. It must be manufactured in accordance with Current Good Manufacturing Practice requirements, which cover:

• Methods.
• Facilities.
• Controls for the manufacturing, processing, packaging, or holding of a drug product.

This helps to prevent manufacturing mistakes or unacceptable impurities and to ensure consistent product quality.

Interchangeable Biosimilar Medications

An interchangeable biosimilar product is a biosimilar that meets additional requirements outlined by the law that allows for the FDA to approve biosimilar and interchangeable biosimilar medications.

An interchangeable biosimilar product may be substituted without the intervention of the health care professional who prescribed the reference product, much like how generic drugs are routinely substituted for brand name drugs. This is commonly called pharmacy-level substitution and is subject to state pharmacy laws.

A health care provider also can prescribe an interchangeable biosimilar product just like they would prescribe a biosimilar or a reference product. Because of the FDA’s high standards for approval, health care providers and patients can be confident in the safety and effectiveness of a biosimilar or an interchangeable biosimilar product, just as they would be for the FDA-approved original product.

Biologics are among the fastest growing segments of the prescription product market. The FDA approval of additional biosimilar and interchangeable biosimilar medications may help stimulate competition. Patients will have more treatment options and potentially less expensive alternatives.

You can search the Purple Book database for information about biological products, including biosimilar and interchangeable biosimilar products, approved by the FDA.

They are used for the treatment of many chronic and severe conditions, including:

Chronic skin diseases (such as psoriasis)

Chronic bowel diseases (such as colon, Crohn's disease, and irritable bowel disorder)

Diabetes

Macular degeneration

Arthritis

Kidney conditions

Some cancers (such as, breast, lung, and colon)

The regulation of insulin as a biologic allows multiple companies to make biosimilar versions of “brand name” insulins, similar to how generics are versions of brand name drugs.

View “Biosimilars: What Patients with Diabetes Need to Know” infographic.

FDA makes sure biosimilars are as safe and effective as the original product by:

• Approving biosimilars after a careful review of data, studies, and tests.
• Monitoring safety and effectiveness after approval.
• Checking for medication quality during production.
• Reviewing patient safety reports made to FDA.

A biosimilar and its original biologic have the same treatment risks and benefits.

Compared with their original biologics, biosimilars:

• Are made with the same types of natural sources.
• Are given the same way.
• Provide the same treatment benefits
• Have the same potential side effects.
• Have the same strength and dosage.

Lower costs

A patient might switch to a biosimilar because of a change in insurance coverage or to save money.

Similar to generic drugs, biosimilars may cost less because manufacturers rely on FDA’s finding that the original biologics are safe and effective.

The lower cost is not a reflection of effectiveness or safety of biosimilars. Because of the lower cost, biosimilars may be covered by more insurance companies and offer patients additional treatment options.

Frequently Asked Questions

Why aren’t biosimilars identical to the original biologics?

Because most biologics are made from living sources, it is normal for both biosimilars and original biologics to have minor differences between batches of the same medication. This means that biologics cannot be copied exactly, and that is why biosimilars are not identical to the original biologic.

FDA carefully reviews the differences between the original biologic and the biosimilar to ensure that biosimilars are as safe and effective as the original biologics.

What are interchangeable biosimilars?

An interchangeable product is a biosimilar that may be substituted without consulting the prescribing doctor, because it meets additional requirements related to the potential for automatic substitution. This practice is called “pharmacy-level substitution” and is subject to state law.

Both biosimilars and interchangeable biosimilars are as safe and effective as the original product they were compared to.

Why would a patient switch from an original biologic to a biosimilar?

A biosimilar is not safer or more effective than the original biologic, but a patient might switch to a biosimilar because of a change in insurance coverage or to save money. Depending on the law in your state, a pharmacist may give you an interchangeable biosimilar, much like they would give you a generic. FDA does not control the cost of drugs, but you can learn more about the price of a specific biosimilar by contacting your pharmacy or insurance company.

Is it safe to take a biosimilar if I started treatment on the reference product first?

Generally, biosimilar medications can be used whether or not you have been treated first with the reference product. Always talk to your health care provider about available treatment options and potential risks and benefits.

How will I know if I’m using a biosimilar for my treatment?

Talk to your health care provider about the medications you are prescribed or are taking. Often, biological medications, including biosimilars, are given in a hospital or an infusion center. Talk to the doctor or nurse who is giving you the treatment. If you have a prescription, your doctor or pharmacist can tell you what you are prescribed and what you are given at the pharmacy.

How are biosimilars different from generics?

Biosimilars are like generics in some ways, in that, both types of medications are compared to a reference (original) product for approval. Biosimilars and generics are both versions of previously FDA approved medications and may offer more affordable treatment options to patients.

Biosimilars and generics are approved through different abbreviated pathways that avoid duplicating certain costly clinical trials.

Both biosimilar and generics go through a rigorous review process. Once FDA-approved, these medications are just as safe and effective as the reference products they are compared to. But, there are differences between biosimilars and generic drugs. For example, biosimilars are generally made from natural and living ingredients and generics are often made from chemical ingredients.

In contrast to a chemical, which is synthesized and can be generally copied, a biologic medication is made from natural and living sources and cannot be exactly copied. So, the information needed to demonstrate that a biologic is biosimilar to another biologic can be much more extensive than what is needed for a generic.

Will I save money by using a biosimilar?

Reducing costs is one reason Congress created the FDA approval pathway for biosimilar medications. However, FDA does not regulate whether insurance companies cover or reimburse the cost of biosimilars. If you have insurance, check with your insurance provider to find out what’s included in your plan. If you are covered by Medicare or Medicaid, the Centers for Medicare & Medicaid Services (CMS) and plan providers can generally provide this information.

Has insulin always been a biologic?

Although insulin is made in living cells, it was historically regulated as a drug made from chemicals. Insulin and other drugs that meet the criteria for a biologic are now regulated as biologics. This does not change the ingredients of insulin or how you obtain medication at the pharmacy.

How will the availability of biosimilar insulins affect me or a person I care for?

The most noticeable change is that patients can be prescribed a variety of additional insulin options once they are available, possibly at a lower cost, depending on your insurance coverage. Depending on the state law, a pharmacist may give you an interchangeable biosimilar insulin, much like they would substitute a generic for a brand-name drug. FDA does not control the cost of drugs, but you can learn more about the price of a specific biosimilar by contacting your pharmacy or insurance company.

The Food and Drug Administration (FDA) has approved many biologics (also called biological products), which are medications generally made from living sources like bacteria and yeast. Biologics treat many conditions like arthritis, diabetes, kidney conditions, cancer, macular degeneration, and chronic skin and bowel diseases, such as psoriasis, Crohn’s disease and ulcerative colitis.

But biologics are often expensive and can be unaffordable, especially for people using several medications. If you’re currently using a biologic and you’re concerned about cost, you and your health care provider may want to talk about switching to a biosimilar. A biosimilar is an FDA-approved biologic that is highly similar to and has no clinically meaningful differences from a biologic previously approved by FDA, which is sometimes described as the original biologic or reference product. Like generic drugs, biosimilars may save you money and are as safe and effective as the original biologic.

Some patients and health care providers might worry that biosimilars are not as safe or effective as the original biologic or that an interchangeable biosimilar is better than a biosimilar that is not an interchangeable biosimilar.  Unwarranted concerns may discourage patients and their doctors from using or switching to a biosimilar, so it’s important to find out the facts.

How is a biologic like other drugs?

FDA-approved biologics, like other drugs FDA approves, are safe and effective medications for treating many illnesses. However, biologics are usually made from living sources such as proteins, living cells, and microorganisms such as bacteria or yeast.  They usually are more complex than other drugs, and more complicated to make.

What is a biosimilar?

A biosimilar is a biologic that is highly similar to an original biologic already approved by the FDA. Both products are made from the same types of sources (such as living cells or microorganisms). Biosimilars also have no clinically meaningful differences from the original biologic. This means biosimilars are as safe and effective as the original biologic for their approved uses.

Is a biosimilar the same as a generic?

Biosimilars and generics are a lot alike. For example, both are versions of FDA-approved medicines and both may offer patients more affordable treatment options. Both also go through a rigorous review process at FDA. Once FDA approves biosimilars and generics, patients and their doctors can be confident that they are just as safe and effective as the products they’re compared to.

There are also some differences between biosimilars and generics. Generics can be easier to copy exactly because their active ingredients tend to be smaller and simpler, while biologics generally cannot be copied exactly, even between batches of the same brand, because their living sources can contain many slight variations. However, FDA requires biologic manufacturers, including biosimilar manufacturers, to carefully control and monitor for differences.  

Should I be concerned if my doctor prescribes a biosimilar or wants to switch me from a reference product to a biosimilar?

No. FDA-approved biosimilars are as safe and effective as their original biologic and you can expect biosimilars to have the same benefits and risks as the original biologic. To be approved by FDA, companies show that patients on biosimilars don’t have any new or worsening side effects as compared to patients on the original biologic.

Your doctor may prescribe or switch you to a biosimilar for any number of reasons, including because it may be less costly, or the biosimilar might be covered by your insurance company.

What is the difference between a biosimilar and an interchangeable biosimilar?

Biosimilars and interchangeable biosimilars both must meet FDA’s requirements for showing that they are highly similar to and have no clinically meaningful differences from a biologic already approved by FDA. The difference is that an interchangeable biosimilar meets additional requirements related to the potential for “pharmacy level substitution.” This means a pharmacy may substitute an interchangeable biosimilar for the reference product without consulting the prescribing doctor, depending on state pharmacy laws.

Should I wait for a biosimilar to be approved as “interchangeable” to use it?

No. Both biosimilars and interchangeable biosimilars meet the same high standard of biosimilarity for FDA approval and both are as safe and effective as the original biologic. Moreover, many biosimilar manufacturers do not seek "interchangeable" status because interchangeability is only relevant to pharmacy-level substitution, which depends on state pharmacy laws. Biosimilars and interchangeable biosimilars can both be used in place of the original biologic.

Will biosimilars cost less? Will my insurance cover it?

FDA does not have a direct role in drug pricing, but FDA’s work does play a critical role in increasing access to safe and effective biologics and supporting a competitive marketplace for biologics. Biosimilars may improve patient access to medicines and lower healthcare costs.

Insurance coverage and reimbursement can affect patient and doctor adoption of biosimilars. In turn, such coverage and reimbursement can depend on many factors, such as insurance plans and formulary coverage. If you have insurance, check with your insurance provider to find out what’s included in your plan. If you are covered by Medicare or Medicaid, check with the Centers for Medicare & Medicaid Services (CMS) and your plan provider.