Novartis comes for Enbrel in latest biosimilar shot at Amgen

A month removed from launching the U.S.'s first biosimilar, Novartis ($NVS) is again setting sights on an Amgen ($AMGN) cash cow, lining up for FDA approval with a copy of the blockbuster Enbrel.

The agency accepted Novartis' application for a homemade version of etanercept, an autoimmune treatment that brought in more than $4.5 billion for Amgen last year and has long been a cornerstone of the company's business. Novartis didn't say when it expects to get a final word from the FDA, but the biosimilar review process is meant to take no longer than 10 months.

Novartis, through its Sandoz generics business, won the first-ever FDA approval for a copycat biologic earlier this year with its version of Amgen's Neupogen, marketed as Zarxio.

But the path to challenging Enbrel in the U.S. is likely to be more complicated. In 2011, Amgen secured new patents related to the antibody that it says will protect the treatment from biosimilar competition through 2029. Novartis, however, is undeterred in its effort to unseat an injection first approved in 1998.

"Sandoz believes that it has a good faith legal basis to challenge the validity of these patents," the company said in a statement. "If Sandoz is unsuccessful in its patent challenge, and the 2028 and 2029 patents are upheld, patients in the U.S. will not have access to a more affordable version of this product until long after it has become available for patients in other countries."

Enbrel already faces competition overseas, where Pfizer ($PFE) controls its marketing rights. Merck ($MRK) and partner Samsung Bioepis won approval for their own etanercept in South Korea last month, and the latter company is moving forward with the same molecule in Europe.

But Novartis, building its repertoire of biosimilars, believes it is the first company to successfully file an application in the U.S.

Zarxio's September launch marked a milestone expected to help knockoff biologics bring in more than $35 billion by 2020 as more and more treatments lose patent protection, analysts say. Among the most common targets are Johnson & Johnson's ($JNJ) Remicade, Roche's ($RHHBY) Herceptin and AbbVie's ($ABBV) Humira.

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