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In vitro data, broad dosage ranges fail to enable patient-treatment claims

Clarifying the enablement standard for pharmaceutical method-of-treatment claims, the US Court of Appeals for the Federal Circuit affirmed a post-verdict grant of judgment as a matter of law (JMOL), finding patents directed to daily administration of a “unit dosage” to cancer patients invalid for lack of enablement. The Court concluded that the specification’s in vitro data and broad dosage ranges – some exceeding the maximum tolerated dose in humans – did not provide sufficient guidance for translating the disclosed results into a workable patient-dosing regimen. Wyeth LLC v. AstraZeneca Pharmaceuticals LP, Case No. 24-2325 (Fed. Cir. July 9, 2026) (Lourie, Linn, Hughes, JJ.)

Pharmaceutical and healthcare company Wyeth owns patents directed to methods of treating gefitinib- and/or erlotinib-resistant non-small cell lung cancer (NSCLC) by administering a daily “unit dosage” of an irreversible epidermal growth factor receptor (EGFR) inhibitor. A jury found that competitor AstraZeneca, which markets the irreversible EGFR inhibitor Tagrisso® (osimertinib), induced infringement and awarded Wyeth $107.5 million in damages. After trial, however, the district court granted AstraZeneca’s renewed JMOL motion, finding the asserted claims invalid for lack of enablement.

Wyeth appealed, arguing that the district court improperly changed its construction of “unit dosage” after trial, applied that revised construction in its enablement analysis, and improperly granted JMOL on enablement grounds.

The dispute centered on the construction of “unit dosage,” which the district court defined as “physically discrete units suitable as unitary dosage for the subject, each unit containing a predetermined quantity of active material calculated to produce the desired therapeutic effect.” Wyeth argued that the claims required only the identification of compounds capable of inhibiting EGFR activity. AstraZeneca countered that, because the claims expressly required daily administration to a patient, they necessarily required a dosage regimen suitable for human treatment.

The Federal Circuit agreed with AstraZeneca, finding that the claims “plainly require the daily administration of a unit dosage to a patient to achieve a therapeutic effect in treating g/e-resistant NSCLC, not merely the identification of compounds capable of inhibiting EGFR activity in vitro.”

The Federal Circuit rejected Wyeth’s contention that the district court had effectively imported US Food and Drug Administration (FDA) approval requirements into the enablement inquiry. The Court emphasized that enablement did not require proof of regulatory-grade safety or efficacy. Because the claims required daily administration to patients, however, the specification had to teach a skilled artisan how to arrive at a workable human-dosing regimen without undue experimentation.

The Federal Circuit determined that the specification failed to do so, as it disclosed only three exemplary compounds (EKB-569, HKI-357, and HKI-272), described their in vitro activity, and provided only broad projected dosage ranges (1-1,000 mg and 2-500 mg) without explaining how to translate those ranges into effective human dosing.

The trial record reinforced the lack of enablement. AstraZeneca presented unrebutted testimony, including from Wyeth’s own experts and co-inventors, that at least two disclosed compounds could not be administered within the claimed dosage ranges without exceeding the maximum tolerated dose in humans. One co-inventor testified that the [...]

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Full Scope of Claimed Invention Must Be Enabled

In a case relating to nucleic acid sequencing, the US Court of Appeals for the Federal Circuit upheld a jury verdict of non-enablement because a skilled artisan would have only known how to successfully practice a narrow range of the full scope of the nucleic acids covered by the asserted claim at the time of the invention. Pacific Biosciences of California, Inc. v. Oxford Nanopore Technologies, Case No. 21-2155, -2156 (Fed. Cir. May 11, 2021) (Taranto, J.)

PacBio sued Oxford for infringement of two patents related to methods for sequencing nucleic acids (such as DNA) using nanopore technology. The methods involve drawing nucleic acids through a nanometer-sized hole formed in a substrate. A voltage is applied to the substrate, and as the nucleic acids pass through the hole, the identity of each nucleic acid is identified based on changes in electric current passing through the substrate.

At trial, Oxford’s lawyer made opening remarks that included references to the potential applications of Oxford’s accused products to the then-emerging global COVID-19 crisis. PacBio immediately objected, and the district court gave exactly the curative instruction that PacBio requested. The district court also required that going forward, the parties give advance notice if they intended to make any reference to COVID-19. Ultimately, the jury found all asserted claims infringed, but also determined that the claims were invalid for lack of enablement under 35 USC § 112. In post-trial motions, the district court denied PacBio’s request that the court grant a new trial because of Oxford’s remark during opening statements regarding the accused products’ potential application to the then-emerging COVID-19 crisis. PacBio appealed.

On appeal, PacBio argued that the jury’s finding of lack of enablement was unsupported by the evidence, citing to testimony from its expert that a person skilled in the art at the priority date would have been able to successfully perform the methods of the asserted claims. The Federal Circuit disagreed, noting that the expert only demonstrated successful practice of the asserted claims for a narrow subset of nucleic acids covered by the claims—namely DNA hairpin molecules. The Court cited evidence where PacBio admitted through a stipulation that it had never performed the nanopore sequencing methods of the asserted claims, meaning its reduction to practice was purely constructive. The Court also noted that Oxford produced evidence that it was not until 2011 (two years after the priority date) that anyone in the field was able to use nanopore sequencing to sequence biological DNA—a different type of nucleic acid within the scope of the asserted claims. Thus, the Court found that PacBio had only demonstrated that a person of skill in the art would have been able to successfully practice a narrow range of the full scope of the nucleic acids covered by the asserted claim. The Court explained that it is not enough for enablement that the relevant artisans knew how to perform some nanopore sequencing before the priority date. Instead, what matters is the scope of the asserted claims, which relate [...]

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In vitro data, broad dosage ranges fail to enable patient-treatment claims

Full Scope of Claimed Invention Must Be Enabled

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