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Celltrion Seeks Joinder with Pfizer IPR Challenging Rituximab-Related Patent

By Seth E. Cockrum on May 18, 2018
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Earlier this month, Celltrion, Inc. (“Celltrion”) filed a copycat IPR petition directed against U.S. Patent No. 7,976,838 (“the ʼ838 patent”) that is essentially identical to a petition filed by Pfizer, Inc. (“Pfizer”).  The PTAB recently instituted review of the ʼ838 patent based on Pfizer’s petition in IPR2017-01923.  Celltrion’s copycat petition was accompanied by a motion for joinder with the currently pending Pfizer IPR.

Celltrion’s motion for joinder asserts that it contains identical grounds to those presented in the Pfizer petition, and thus would not create any additional burdens on the parties or impact the trial schedule.  Celltrion further explains that it conferred with Pfizer’s counsel and agreed to proceed in a limited “understudy” role, unless Pfizer is terminated from the proceedings.  As part of this understudy role, Celltrion agreed to not produce its own testifying witnesses, file any substantive papers (unless those papers do not affect Pfizer), or participate in the oral hearing.

This is the third time Celltrion has challenged the ʼ838 patent in an IPR.  Celltrion’s first challenge to the ʼ838 patent was via another copycat petition based on Boehringer Ingelheim’s (“Boehringer”) petition filed in IPR2015-00417.  Celltrion filed a motion for joinder in that case but while the motion was pending, Boehringer requested adverse judgment and the IPR was terminated.  Celltrion then requested dismissal of its copycat petition without prejudice, which the PTAB granted.  Celltrion subsequently filed its own IPR challenging the patentability of the ʼ838 patent, but the PTAB declined to institute review.

In Celltrion’s first copycat petition in the Boehringer IPR, Celltrion did not retain an expert of its own to support its petition.  Rather, Celltrion relied on the same exhibits and expert declaration that Boehringer submitted.  However, once Boehringer requested adverse judgment, Celltrion was no longer able to work with that expert.  Without an expert of its own, Celltrion could not proceed in the IPR.  Celltrion apparently learned from this experience, and supported its most recent copycat petition with expert declarations submitted by experts independent of those relied on by Pfizer.

The lesson here for parties filing copycat petitions is that they should consider submitting independent expert declaration(s), even if those declaration(s) are essentially identical to those supporting the petition being copied, to avoid any problem with continuing in the IPR if the first-filing party drops out of the proceeding.

Photo of Seth E. Cockrum Seth E. Cockrum
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  • Posted in:
    Intellectual Property
  • Blog:
    Biosimilars Law Bulletin
  • Organization:
    Rothwell Figg
  • Article: View Original Source

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