Naming conventions are another hot-button issue. Critics want biosimilars to carry vastly different names from biologics to avoid confusion and prevent adverse reactions. Biosimilar makers say carrying the same non-proprietary name would help boost confidence about the safety and efficacy of their products. The FDA sought middle ground last August when it proposed adding a four-letter suffix to the non-proprietary names shared with brand-name biologics. The agency has not yet finalized guidance on naming.
These hurdles raise questions as to whether the biosimilar market could ever reach its potential.
From a financial perspective, sales of Zarxio have not “lit the world on fire,” said Chris Raymond, biotechnology analyst for equity research-investment firm Raymond James.
That might be because Amgen has diverted patients away from Neupogen in favor of its longer-acting version, Neulasta. Medicare's current reimbursement for biosimilars doesn't help. Payment to doctors for prescribing outpatient drugs is a product's average sales price plus 6%. That creates an incentive for physicians to use more expensive medications.
Zarxio's third challenge came when its wholesale price was listed only 15% lower than Neupogen's. Sandoz had projected it to be 30% cheaper.
Experts say biosimilar producers will have to market their products to new patients rather than persuade those who have been using their brand-name counterparts to switch.
Dan Mendelson, president of Avalere Health, said that while he estimated the biosimilar market will eventually be worth tens of billions, growth will occur slowly in the U.S., as consumers get more comfortable with choosing such drugs over their originator counterparts.
“It's not like the whole thing is going to take off like a rocket ship,” Mendelson said. “This is going to be measured in a slow change in the marketplace.”