Rehearing Wins Institution of Inter Partes Review

PTAB ALERT By Christopher Lacenere, Ph.D.. A member of our Patent Practice Group

In a rare move, the Patent Trial and Appeal Board (“the Board”) granted the institution of an inter partes review (“IPR”) upon a request for rehearing after initially denying its institution.  IPR2017-00731 Paper No. 29.  However, don’t expect such reversals to become commonplace.  This case involved a panel of administrative patent judges who were not sufficiently familiar with negative limitations in a patent claim. Consequently, upon being denied institution, the petitioner needed a rehearing to educate the judges on how to correctly interpret such limitations.

Hospira, Inc. (“Petitioner”) filed a petition requesting that claims 1-14 of U.S. Patent No. 7,846,441 (“‘441 patent”), owned by Genentech, Inc. (“Patent Owner”), be reviewed as being obvious over the prior art.  The ‘441 patent relates to the treatment of disorders, such as breast cancer, characterized by the overexpression of ErbB2, a transmembrane protein related to the epidermal growth factor receptor. Claim 1 recites a method of treating a cancer patient with an anti-ErbB2 antibody and a taxoid, “in the absence of an anthracycline derivative.”

Petitioner argued that claims 1-14 of the ‘441 patent were unpatentable as being obvious over Baselga 1996 and Baselga 1994.  Baselga 1994 teaches that ErbB2-overexpressing tumors grown in mice resulted in 35% growth inhibition following a treatment with either the 4D5 anti-ErbB2 antibody or paclitaxel (a taxoid) alone, and a 93% growth inhibition following treatment with a combination therapy of the antibody and paclitaxel.  A combination treatment of the antibody and doxorubicin (an anthracycline derivative) resulted in 70% growth inhibition.

The Board initially declined to institute an IPR.  Although it acknowledged that Baselga 1994 teaches the combined treatment of an anti-ErbB2 antibody with either a taxoid or with an anthracycline, but not with both, the Board nonetheless reasoned that nothing in Baselga 1994 or Baselga 1996 suggests that a person of ordinary skill in the art would have avoided anthracyclines in pursuing a combination therapy with an anti-ErbB2 antibody and a taxoid.  Without additional evidence or argument that a skilled artisan would have avoided anthracyclines, the Board concluded that Petitioner had not established a reasonable likelihood it would prevail in showing that the challenged claims would have been obvious over Baselga 1994 and Baselga 1996. More...