Anxiety and Optimism on the Brink of Biosimilars

Linda Brookes, MSc


July 21, 2015

In This Article

Editor's Note: On July 21, 2015, the US Court of Appeals for the Federal Circuit, the nation's top patent court, ruled that Sandoz will be allowed to sell Zarxio™ (filgrastim-sndz), the first biosimilar drug to be approved in the United States and a copycat version of Neupogen® (filgrastim), beginning in September 2015.

"Highly Similar" Biologic Agents

Biosimilars, biologic agents developed to be "highly similar" to approved drugs with expired patent protection, appeared to be on the verge of becoming available in the United States with the US Food and Drug Administration (FDA) approval of Zarxio® (filgrastim-sndz, Sandoz) in March 2015.[1,2] Although, at the time of writing, the launch of Zarxio has been delayed by legal action taken by the manufacturer of the original (reference) biologic Neupogen® (Amgen), the arrival of biosimilars is still keenly anticipated by clinicians in rheumatology, gastroenterology, and oncology in particular, where biologics are most frequently used, and by pharmacists, who are closely monitoring the implications of biosimilars for formulary management.

For an overview of how health professionals view the coming integration of biosimilar use into clinical practice in the United States, Medscape spoke with Jonathan Kay, MD, director of clinical research, Rheumatology Division, UMass Memorial Medical Center, and professor of medicine, University of Massachusetts Medical School, Worcester, Massachusetts; and Maureen Sullivan PharmD, BCPS, chair and associate professor, pharmacy practice, Touro College of Pharmacy, New York, New York, to address some of the issues that are still being debated about biosimilars. Both Dr Kay and Dr Sullivan are looking forward to the arrival of biosimilars. According to Dr Kay, biosimilars represent "the beginning of a new era, an exciting time in the United States,"[3] and Dr Sullivan is "cautiously optimistic" about them. "There is definitely high anxiety about biosimilars across the medical field and how to handle them," she states.

Why Has the FDA Taken So Long to Approve Biosimilars?

The approval of Zarxiocame 5 years after legislation was enacted to allow approval of biosimilars in the United States[4] and 9 years since the first biosimilars were approved anywhere in Europe.[5] Dr Sullivan believes that the FDA has had good reasons for taking longer to accept and approve biosimilar applications. "The FDA is under a lot of scrutiny after a couple of episodes in which drugs have been pulled from the market," she says. "They had been notified, and people were trying to get their attention, but they didn't act quickly enough. So they are being cautious now. The process works 99% of the time, but drugs like Vioxx® [rofecoxib] have been pulled," Dr Sullivan notes. Vioxx, a prescription nonsteroidal anti-inflammatory drug [NSAID], was approved for use by the FDA in 1999 but was eventually withdrawn from the market by the manufacturer, Merck,[6] amid accusations that the FDA had ignored warnings about safety concerns with the drug.[7]

Another reason for the delay in approval of biosimilars according to Dr Sullivan was that, until recently, the FDA had issued no formal regulatory guidance. Four draft guidance documents were published in April 2015,[8,9,10] after approval of Zarxio. "That was a little odd, sort of putting the cart before the horse," says Dr Sullivan. However, she has full confidence in the FDA. "I have been following this since the pathway for biological products demonstrated to be 'biosimilar' to or 'interchangeable' was signed into law back in 2010," she explains.[11] "I was in managed care at that time, so on the insurers' side we were obviously looking out for this for cost reasons and to see how the FDA was going to handle it. The amount of time that it took for the FDA to approve the first biosimilar shows due diligence. They didn't rush into it, they didn't start approving biosimilars just because of demand, they took their time to make sure that what they were doing was right by going through the proper channels." Dr Sullivan and Dr Kay agree that physicians should be reassured that FDA-approved biosimilars are as safe and effective as the reference product.


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