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Frequently Asked Questions: Generic and Biosimilar Medications


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What is a generic medication?

A generic medication is a product that is bioequivalent to a brand-name medication whose patent protections have expired. They are also known as a “follow-on” medications.

As part of the generic medication approval process, the FDA requires generics to have the same active ingredient, strength, dosage form and route of administration as the brand-name medication. They also must be manufactured according to federal quality control regulations.

Manufacturers must show that the generic medication works the same way in the body and produces the same clinical benefit as the brand name medication. This is referred to as “bioequivalence.”

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Do generic medications have the same benefit as name-brand medications?

Yes. The FDA has a thorough review process and guidelines in place to evaluate the equivalence of proposed generic medications to brand-name medications. If the FDA reviews and approves a generic medication, it means the manufacturer has provided sufficient evidence that the generic will have the same benefits as the brand-name medication.

The FDA evaluates generic medication candidates through Abbreviated New Drug (Medication) Applications.

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What is the difference between generics and biologics?

The term “generic” applies to medications made through a chemical manufacturing process. Production of generic medicines is more straightforward. The active substance in the generic medicine is identical to the active substance within the original brand.

Biologics are more complex. They are made from living sources rather than chemical processes. The terms for an equivalent medication for a biologic are “biosimilar” or “follow-on biologic.”

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What do generic and biosimilar medications have in common?

Biosimilars and generics are both versions of medications already approved by the FDA. Like generics, biosimilars have the same mechanism of action and work in the same way as the original medication. They provide the same benefits and are given at the same dose, strength and form as the original medication. Generics are follow-on medications to brand name medications while biosimilars are follow-on medications to biologic medications.

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How are biosimilar medications evaluated by the FDA?

The FDA will only approve a biosimilar medication if it has the same mechanism of action, route of administration, dosage form and strength as the reference medication. Additionally, a biosimilar can only be approved for the indications and conditions of use that have been previously approved for the reference medication. Under a law passed in 2009, a biological medication may be demonstrated to be biosimilar if data show that:

  • The medication is highly similar to the already-approved biological medication
  • It has no clinically meaningful differences in terms of safety, purity and potency from the reference medication
  • The proposed biosimilar is expected to produce the same clinical result
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Will there be follow-on medications for more DMTs?

It’s possible that eventually there will be. The patents protecting the brand-name medication must expire before any medication may be produced. Then manufacturers of follow-on medications would need to apply to the FDA with a request for approval of their medications.

Some MS medications currently have generics available, including, but not limited to, Copaxone (glatiramer acetate, Glatopa), Gilenya (fingolimod), Tecfidera (dimethyl fumarate) and Aubagio (teriflunomide). The first biosimilar of a DMT is expected in 2024.

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Where can I get more information about generic medications and biosimilars?

The FDA’s website has information about generics and biosimilars and processes for their approval.


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