“A single inartful statement in the prosecution history”

Genentech v. Iancu (Fed. Cir. 2020)

Hospira, Samsung Bioepis, Celltrion, and Pfizer each filed one or more inter partes review (IPR) petitions challenging Genentech breast-cancer slow-down patents: US7846441 and US7892549.  The patents recognize that some breast cancer patients make too much ErbB2 protein.  The offered solution is administration of an antiErbB2 antibody and “a taxoid, in the absence of an anthracycline derivative.”  The claims do not require a specific dosing except that it be adequate to do the job without causing major problems:

… in an amount effective to extend the time to disease progression in said human patient, without increase in overall severe adverse events.

‘441 patent, claim 1 (elsewhere claimed “effective amount”). The Board found a number of the claims invalid and Genentech appealed.  None of the petitioners participated in the appeal to defend the Board’s decision as part of a settlement with Genentech, but the USPTO intervened.

The question on appeal is the meaning of the claimed “amount effective to extend the time to disease progression.”  The problem for the patentee is that the specifications do not define the required comparisons. During prosecution the examiner originally rejected “extend the time to disease progression” as indefinite after explaining that the specification “never set[s] forth what the extension of time to disease progress is relative to.”

After receiving the indefiniteness rejection during prosecution, the patent applicant did not amend the claims but rather explained that “clearly” the effectiveness of the claimed combination should be compared with the baseline “relative to an untreated patient.”  Later, during the IPR, the Board used the statement to construe the claim term as stated and find the claim invalid as obvious.

Genentech argues that its claims should not be limited “Based on a single inartful statement in the prosecution history.” In particular, Genentech argues that the claimed improvement in disease progression should be compared to treatment with paclitaxel (the taxoid alone) – not with an untreated patient.  And, that in that framework the improvement in outcomes would have been nonobvious.

On appeal, the Federal Circuit has affirmed the PTAB claim construction and the obviousness determination.  The appellate panel noted that Genentech might have an argument except for the fact that “[t]he specification does not … expressly define the disputed terms.” In its indefininteness rejection, the examiner asked particularly — is the time “relative to untreated patients? Pateients who received antibody or taxoid alone? …”  The patentee then responded “untreated patients” and is now arguing that the correct answer should have been “taxoid alone.”

Genentech expressly rejected this comparator during prosecution and instead clearly stated that it was effectiveness relative to an untreated patient. Genentech provided an unequivocal, direct response to the examiner’s inquiry—that the term “extend the time to disease progression” was compared to an untreated patient.

Slip Op.  The response discussed above was provided in the ‘441 patent prosecution history.  In the appeal, the Federal Circuit also agreed that the same construction should apply in the ‘549 patent “which shares a specification and is in the same patent family.” “We see no error in the Board’s constructions.”