Each time biosimilar manufacturers proceed down the approval pathway laid out in the Biologics Price Competition and Innovation Act, commonly referred to as the BPCIA, they are vulnerable to patent infringement litigation from reference product sponsors (RPS), according to a blogpost by Tasha Francis and Jenny Shmuel, PhD, 2 attorneys from the law firm Fish & Richardson. The earliest this patent litigation can begin is 21 days after the FDA accepts an abbreviated Biologic License Application (aBLA) from a biosimilar maker.
Two cases: Sandoz, Inc v. Amgen, Inc and Celltrion Healthcare Co v. Kennedy Trust for Rheumatology Research (both decided in 2014), established that biosimilar applicants can’t typically be sued before an aBLA is filed and clinical trials are still ongoing, because there is no immediate threat of injury to the RPS.
The BPCIA establishes steps for resolution of patent claims by the RPS and the biosimilar applicant, which is known as the “patent dance.” The law requires the biosimilar applicant to provide the RPS with a copy of the biosimilar’s application to the FDA for review, as well as information about the biosimilar’s manufacturing processes, including all patents involved, no later than 180 days before the date of the first commercial marketing of the biological product. However, a judge presiding over litigation in federal court in 2016 between Amgen and Sandoz about the patent dance ruled that the patent dance is optional, and that compliance cannot be forced. The decision was appealed to the Supreme Court and is currently being reviewed, but it is an open question whether the courts will allow a RPS to sue for patent infringement when a biosimilar applicant refuses to provide any information on the existence or status of an aBLA.
Therefore, although the BPCIA states that applicants have 21 days after the FDA accepts their biosimilar application for review to bring a patent infringement suit, the practical issue remains that the RPS may not be aware it has a right to sue because there is no public posting when the FDA accepts an application for review. The only certain public posting about a biosimilar’s status is the FDA’s actual approval of the biosimilar drug; thus, the RPS would have to find out of the application’s acceptance by some other method. For example, if the biosimilar company is publicly traded the applicant may have a duty to inform shareholders when it files an aBLA application or when the FDA accepts filings for review. Press announcements by biosimilar applicants also provide information about FDA reviews of aBLAs.
Francis and Shmuel conclude, “At the earliest, a biosimilar applicant may be sued 21 days after its aBLA is accepted for FDA review, but the individual circumstances may in practice delay any infringement suit. Should the biosimilar applicant wish to delay suit, it should consider declining to engage in the patent dance and keeping FDA acceptance of the aBLA confidential as long as possible.”
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