Lower-cost insulin available with interchangeable biosimilars

A young man checks his blood sugar while sitting on the couch.

Interchangeable biosimilars are driving cost savings and access for patients with diabetes

In July 2021, the U.S. Food and Drug Administration (FDA) approved Semglee® as the first interchangeable biosimilar for Lantus®, followed by RezvoglarTM in November 2022.

Semglee and Rezvoglar are long-acting insulin used to control blood sugar in adults and children with type 1 diabetes mellitus and adults with type 2 diabetes mellitus.

The interchangeability designation means that a pharmacy can substitute either Semglee or Rezvoglar for Lantus without needing to go back to the prescriber, depending on state pharmacy laws. Almost all states allow for this.

How will this help people who use insulin?

The main benefit people see is cost savings, according to Robert Sardon, a registered pharmacist with Express Scripts® Pharmacy who supports patients with diabetes. Biosimilars in the U.S. typically have launched with initial list prices 15% to 35% lower than the original product’s list price.

Sardon said consumers can look at it as being similar to automatically substituting generics for brand-name drugs.

Having an interchangeable biosimilar product also makes things more efficient and saves everyone time. Many pharmacists no longer have to get pre-approval from prescribers to have Lantus prescriptions changed to Semglee or Rezvoglar, depending on the state the prescriber resides in and how the prescription is written.

Are Semglee and Rezvoglar generic medications?

Not exactly, according to Sardon. Biologics, like Lantus, Semglee, and Rezvoglar, are made from living sources, such as bacteria and yeast. That makes them different from conventional medications, which are commonly made from chemicals.

When the FDA approves an original biologic, like Lantus, that becomes known as the reference product. A biosimilar, like Semglee or Rezvoglar, is made with the same type of living organisms and has the same clinical characteristics as a reference product.

“Although the biosimilar must have the same strength, dosage, and treatment benefits as the reference product, it is not considered a true generic because of the slight variations from batch to batch,” Sardon said.

How do I know Semglee and Rezvoglar are safe and work?

In order to be approved as an interchangeable biosimilar by the FDA, Semglee and Rezvoglar had to follow a rigorous three-step process:

  1. First, the pharmaceutical manufacturer had to show that it’s biosimilar to Lantus — meaning highly similar with no clinically meaningful differences in safety, purity, and potency.
  2. Next, they had to show that it works the same as Lantus and has the same results in any patient.
  3. The final step was to show that switching between the two products doesn’t increase safety risks or decrease effectiveness. This was done through a switching study, in which patients alternate between the two products multiple times over a specific period of time.

The FDA will continue to monitor the safety and effectiveness of Semglee and Rezvoglar over time, just as it does with all medications.

Talk to your pharmacist about any new medications

If you have any questions about whether these medications (or any medication) is right for you or your loved ones, please reach out to your prescriber or pharmacist. Our Express Scripts® Pharmacy pharmacists are available 24/7 to answer questions and give you peace of mind.


Original posted date: November 12, 2021

Posted date: February 08, 2024

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