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Neupogen Biosimilar Update: Zarxio Now FDA Approved

by The GoodRx Pharmacist on March 17, 2015 at 1:58 pm

On March 6, 2015, the FDA approved the first biosimilar for distribution in the United States. This is a huge approval, and an accomplishment for the pharmaceutical company, Sandoz, and their biosimilar, Zarxio (filgrastim-sndz).

This is such important news because biosimilars like Zarxio will offer a reduced cost alternative therapy to their expensive biologic counterparts where there have been previously been no lower-cost options.

What is a biosimilar again?

Remember biologic medications? In short, they are specialty drugs made from living cells that are typically not used as first options for treatment. A biosimilar is like a generic version of a biologic—but because they’re made from living cells instead of a chemical formula (like more familiar prescripions), they will be slightly different.

What is the reference biologic product for Zarxio?

The brand name biologic “equivalent” for Zarxio is Neupogen (filgrastim). Neupogen and Zarxio are used to increase white blood cell counts to help reduce the risk of infection, as in patients receiving chemotherapy.

For more information on Neupogen see the manufacturer website here.

Can Zarxio be used for all the same indications as Neupogen?

Yes. Zarxio can be used for the same indications as Neupogen.

In what dosage forms and strengths will Zarxio be available?
Zarxio will be available as single-use pre-filled syringes in both 300 mcg/0.5 mL and 480 mcg/0.8 mL strengths.

If my doctor writes a prescription for Neupogen can the pharmacist substitute with Zarxio?

NO. This is important. Zarxio is a biosimilar, NOT an interchangeable product.

Interchangeable products are what you would usually consider generic medications. They can be substituted for brand name drugs if available, without needing to consult your prescriber.

For biosimilars like Zarxio, your prescriber must write your prescription for the medication you will use.

When is Zarxio expected to be available?

At this time the manufacturer, Sandoz, has not set a release date. However, it could be available as early as May 2015.

What are the most common side effects of Zarxio?

Side effects of Zarxio may include aching in bones or muscles and redness, swelling, or itching at the injection site.

More important information on Zarxio:

For more background on the FDA approval of Zarxio click here.

For more information and on Zarxio check out the manufacturer website here.

And for a deeper look at biologics and biosimilars, please check out my previous articles—you can find another post on the upcoming Neupogen biosimilar here, and an overview of biologics here.


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