Busy times: US FDA accepts Sandoz's biosimilar filgrastim filing

The US Food and Drug Administration (FDA) agreed to review Sandoz’ biosimilar – marketed outside the US as Zarzio – last night in a decision that prompted a flurry or reports about the Novartis unit being the first to file under the agency’s new biosimilar pathway.

What Sandoz actually said is that it is “the first company to announce it has filed for approval of a biologic under the biosimilars pathway." ​Whether other firms have filed and not announced is unclear.

Sandoz also said, somewhat confusingly, the FDA had accepted its “Biologics License Application(BLA) for filgrastim, which was filed under the new biosimilar pathway created in the Biologics Price Competition and Innovation Act of 2009 (BPCIA).”​

351(a) vs 351(k)​

For clarity, most originator biopharmaceuticals are filed under a full BLA, the 351(a) pathway, for which the applicant must provide data proving the product meets applicable standards without relying on previous FDA findings for any similar drug.

Sandoz has filed its version of filgrastim “​under the 351(k) pathway, the new biosimilar pathway​” according to spokesman Chris Lewis, who told BioPharma-reporter.com that putting together the submission had been a “learning experience​.”

"The main hurdle is that this is a new pathway and we are the first company to announce FDA acceptance for a filing under it, so it is a learning experience for all involved."​

“We are excited, not daunted. Sandoz is used to leading the way in biosimilars,"​ Lewis said, adding that "we also pioneered the process in Europe from the industry perspective, and look forward to the opportunity of doing so again in the US."​

He also said: “We have had a strong and collaborative interaction with FDA and look forward to a rapid processing of our submission​.”

Dear Amgen…​

Under the 351(K) pathway Sandoz has 20 days to provide Amgen with a copy of its filing and details of how the drug will be made with the US drugmaker then having 60 days to return a list of patents it could claim are infringed and those it is willing to license.

60 days after that Sandoz must provide a list of patents it believes that Amgen could claim are infringed as well as the details of legal arguments against any potential suits or a written commitment not to start production until after the patent expires. Amgen must respond in kind.

After these exchanges Sandoz and Amgen must begin “good faith negotiations​” to identify which patents will be tested in lawsuits. If agreement is not reached in 15 days the firms must exchange lists of patents and Amgen must bring any suits in 30 days.

Clearly, Sandoz and Amgen are going to be busy. For what it is worth BioPharma-Reporter.com can confirm that – according to Lewis - “Filgrastim will be manufactured at state-of-the-art facilities in Europe. The drug substance is manufactured exclusively by Sandoz​.”