Corporate Counsel Daily, Court largely denies summary judgment with respect to anti-nausea patents, (May 21, 2024)

By Justin Marcus Smith, J.D.

The court had to consider weight per volume infringement contentions in comparison with weight per weight percentage claims.

Heron Therapeutics, Inc. was mostly not entitled to summary judgment with respect to its Hatch-Waxman Act patent case against Fresenius Kabi USA, LLC in connection with two anti-nausea patents, held the federal district court in Delaware. Although Heron’s expert opinions did not go beyond what it pleaded, and limiting claims to exact weight per weight percentages would have been impossible, Heron did not meet its summary judgment burdens with respect to physical stability and any Fresenius knowledge of induced infringing acts. However, the court did grant Heron’s motion for summary judgment of no indefiniteness with respect to the “physically stable” claims of one of the patents. The court otherwise partly granted Fresenius’s two Daubert motions with respect to the opinions of two Heron experts (Heron Therapeutics, Inc. v. Fresenius Kabi USA, LLC, No. 22-985-WCB (D. Del. May 15, 2024)).

Background. Patent holder Heron Therapeutics, Inc. brought a Hatch-Waxman Act patent case, involving U.S. Patent Nos. 9,561,229 (’229 patent) and 9,974,794 (’794 patent), against Fresenius Kabi USA, LLC. The court said the patents had substantially identical specifications and contained both composition and method claims pertaining to non-oral administration of aprepitant, i.e., drugs designed to prevent nausea and vomiting in chemotherapy patients.

Fresenius initially argued that invalid claims could not be infringed, and as to method claims, it argued only that it did not teach, instruct, or encourage the use of its accused product to treat nausea and vomiting. Fresenius later raised, for the first time in its expert reports, a detailed noninfringement argument pertinent to its abbreviated new drug application (ANDA). A key aspect of this dispute was whether the Heron patent claims recited ingredient concentration on a weight per weight percentage basis when compared to Heron’s infringement contentions and Fresenius’s ANDA measured on a weight per volume basis.

Infringement. The court denied Heron’s motion for summary judgment that Fresenius infringed the method claims of both patents. The court noted, first of all, that Fresenius did not rebut most of Heron’s summary judgment infringement assertions.

From there, starting with Fresenius’s procedural objection that Heron’s expert opinions went beyond what Heron pleaded, the court said that objection failed because the court found Heron met its disclosure obligations about component concentrations in the accused product. Heron asserted that the Fresenius ANDA met each of the weight per weight percentage claim limitations, and it also identified the weights per volume of each Fresenius ANDA product component. Accordingly, Heron placed Fresenius on clear notice of Heron’s infringement theory, i.e., that the weight per volume figures Fresenius reported for its ANDA product, satisfied the weight per weight percentage limitations of the patent claims.

As to Fresenius’s next argument, that there were lingering factual disputes about whether the Fresenius ANDA product satisfied the weight percentage limitations of the Heron claims, the court concluded it would make no sense to limit the claims to exactly the weight per weight percentages set forth because that was a physically impossible requirement. The standard practice would be to apply a range that would round to the claimed number. Doing so here would yield Heron’s proposed construction. Fresenius did not suggest the use of a differing rounding convention.

As to the third Fresenius objection to summary judgment about physical stability limitations, the court noted first that a party can prove a limitation is met without following the “precise testing protocol called for in the patent and the court’s claims construction.” However, the court found Heron did not meet its burden. Conversely, Fresenius’s own expert could not say the Fresenius ANDA product would become unstable after one week. The court accordingly denied summary judgment as premature with respect to infringement of the ’794 patent.

As to the fourth Fresenius objection to summary judgment, consisting of a three-fold argument that it did not have requisite knowledge and specific intent to induce infringement, the patent was invalid, and its ANDA was diluted before administration, the court easily disposed of the last two arguments: belief of invalidity was not a defense to a claim of induce infringement; and, the Fresenius label instructed physicians to “not dilute” intravenously.

However, the court found Fresenius’s disavowal of knowledge more persuasive. Although Fresenius clearly knew about the patent because its challenge to the patents brought about the case, the court nonetheless concluded Heron did not show that Fresenius’s knowledge of the induced infringing acts was beyond dispute.

Indefiniteness. The court granted Heron’s motion for summary judgment of no indefiniteness with respect to the “physically stable” claims of the ’794 patent. The court deemed Fresenius’s argument in opposition, that there was no upper boundary for claims stable for at least a week, to be meritless. The court reasoned that if a composition is stable for more than a week, the claim would still cover it.

Expert testimony. The court partly granted Fresenius’s challenge to the opinion of Heron’s expert. Fresenius objected to the expert’s opinions on three ostensible grounds: 1) the expert was not a person of ordinary skill in the art; 2) the expert applied an incorrect standard for a person of ordinary skill in the art, a standard that did not accord with either party’s definition; and 3) the expert applied a “lead compound analysis” that applied to patents in which the claim covered an active ingredient, not a formulation.

As to Fresenius’s first objection, the court agreed with Heron that an expert need not be a person of ordinary skill in the pertinent art for the expert’s testimony to be baseline admissible, but that was true only up to the point that the testimony was not being offered as that of a skilled artisan in a patent suit.

The court found that most of the expert’s opinions easily satisfied Fed. R. Civ. P. 702 and Daubert; however, three paragraphs related to the expectations of a person of ordinary skill in the art. Two of these were pertinent to Fresenius’s second objection because they stated what a pharmaceutical scientist in 2014 would have thought about intravenous administration of aprepitant. That made these two inadmissible. The third paragraph challenged the validity of another expert’s opinion about the expectations of the ordinary artisan, but it did so solely based on personal knowledge of aprepitant development.

On Fresenius’s third objection, the court had not yet made a determination of the legal sufficiency of Heron’s position that a lead compound analysis was appropriate to this case, hence this third part of Fresenius’s Daubert challenge was wholly ineffective.

Second expert. The court partly granted Fresenius’s Daubert motions to exclude two categories of opinions expressed by another Heron expert, a chemical engineer: 1) opinions based on the doctrine of equivalents; and 2) validity opinions relating to the long-felt unmet need for a way to administer aprepitant non-orally.

As to the doctrine of equivalents, the expert had reserved the right to address equivalency of any Fresenius-disputed claim term. The reply report purported to set forth a doctrine of equivalents opinion about three things: 1) the scope of weight per weight percentage limitations; 2) induced infringement of the method claims; and 3) the physical stability of the Fresenius ANDA products.

The court excluded the expert’s opinions about weight per weight percentage limitations because the court’s claim construction, which it said largely tracked the expert’s doctrine of equivalents on the same subject, superseded them.

Next, despite the expert’s purported invocation of the doctrine of equivalents, the court found the report did not actually disclose that theory. For this reason, the court declined to exclude the opinion on the subject, that is, unless he were to testify that the method claims infringed under the doctrine of equivalents.

And last with respect to the doctrine of equivalents, the court found the expert’s opinion about physical stability limitations was not that the Fresenius ANDA product features were equivalent, but rather that the testing Heron did was equivalent to the testing the court found would prove physical stability. The court declined to exclude this, but it said it would not permit the expert to testify that the Fresenius ANDA met physical stability limitations under the doctrine of equivalents.

Turning to the second category of the opinions, about invalidity, the expert was a chemical engineer, so he did not have any clinical experience to speak directly to the long-felt need for non-oral aprepitant administration. However, the court disagreed with Fresenius that the expert had become the mere mouthpiece for another expert. He permissibly based his own opinion partly on what a different expert believed to be the case in an unfamiliar area. Accordingly, he could not testify as a clinician, but he could incorporate the opinions of other experts in his own analysis of secondary obviousness considerations.

The case is No. 22-985-WCB.

Judge: Bryson, W.

Attorneys: Jack B. Blumenfeld (Morris, Nichols, Arsht & Tunnell LLP) for Heron Therapeutics, Inc. Daniel Taylor (Smith, Katzenstein & Jenkins LLP) for Fresenius Kabi USA, LLC.

Companies: Heron Therapeutics, Inc.; Fresenius Kabi USA, LLC

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