Coherus Petitions for IPR of Key Etanercept Patent

Coherus BioSciences announced this week that it has filed a petition for inter partes review (IPR) of a key patent protecting Amgen’s etanercept (Enbrel). Patent 8,163,522 (also known as the ‘522 patent) concerns a process for isolating non-soluble proteins. If the Patent Trial and Appeal Board (PTAB) institutes the petition and sides with Coherus, the California biosimilar developer will be a step closer to finally bringing a late-pipeline biosimilar product to market.

Shares of Coherus’ stock rose on the news of the IPR petition, with investors eager to see the drug maker challenge Amgen’s lucrative biologic in the US marketplace. Etanercept earned Amgen $8.87 billion in global sales in 2016.

Coherus is not the first entity to challenge the ‘522 patent protecting the blockbuster drug, however. In 2015, the Coalition for Affordable Drugs asked the PTAB to invalidate several of the patent’s claims, including those concerning composition and manufacturing, but the PTAB did not institute the review. In a separate case, Sandoz has challenged Amgen on the ‘522 patent during ongoing Biologics Price Competition and Innovation Act (BPCIA) litigation.

Coherus also indicated that it planned to petition for an IPR of a second etanercept patent—also concerning isolating non-soluble proteins and also currently being challenged by Sandoz under the BPCIA—in the near future.

“The ‘182 and ‘522 patents do not expire until 2028 and 2029,” said Dennis M. Lanfear, president and CEO of Coherus. “This could result in over 30 years of patent coverage for Enbrel. We believe this is an anti-competitive and unjustified distortion in our patent system that threatens to inflict another dozen years of massive costs on the healthcare system given Amgen’s history of substantial price increases for this drug which already total over 400% since launch.”

The announcement of the IPR petition comes 2 weeks after Coherus sought a stay of discovery in an unrelated BPCIA litigation over CHS-1701, a pegfilgrastim biosimilar referenced on another Amgen drug, Neulasta. In its motion, Coherus claimed that it needed to preserve its resources, and that “because of a recent FDA rejection of its drug application, will have no revenue until its anticipated mid-2018 launch of the product at issue in this case.”

Coherus reported in its second quarter earning call that it planned to resubmit its biologics license application for CHS-1701 by the end of 2017, and that it is currently in discussions concerning commercial partnering on the drug in some international territories.