Today, the Food and Drug Administration (FDA) ushered in a new era of medicine, approving the first non-brand name version of a biological drug. 

The drug, called Zarxio, helps patients grow more white blood cells when they have been wiped out by chemotherapy.

Zarxio, made by Sandoz, is a lower-cost copy, or biosimilar version, of Amgen’s biologic drug Neupogen, generically known as filgrastim. Neupogen earned FDA approval in 1991. 

Biological drugs have transformed cancer care as well as the care of some other diseases, including juvenile arthritis. But the drugs are costly and no non-brand name competitors had been approved before today. 

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“Biosimilars will provide access to important therapies for patients who need them,” FDA Commissioner Dr. Margaret A. Hamburg said in a press statement.

The FDA had to devise a new approval process for biosimilar drugs, which is why it’s taken so long for any to be approved.

A law pushing the agency to make biosimilars available, because they are cheaper than brand-name drugs, was part of the Affordable Care Act. 

Most pharmaceutical medications are made from synthesized chemicals, so a generic equivalent can easily demonstrate that it has the same chemical makeup. 

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The FDA compares biosimilar drugs to the original drug. They must show that they have the same indications, mechanisms, and dosages. The facilities where biosimilars are manufactured must also meet FDA standards.

“As the global leader in biosimilars, we are honored to be the first company to successfully work with the FDA to navigate the U.S. biosimilar pathway, and we look forward to making this high-quality biosimilar available to patients in the U.S.,” Carol Lynch, the global head of biopharmaceuticals and oncology injectables at Sandoz, said in a press statement.

Zarxio was approved as a biosimilar, but it is not completely interchangeable with Neupogen. That means that, unlike with a true generic, a doctor must approve the substitution of Zarxio for Neupogen.