Just months after a jury ordered payment to Pfizer in the patent infringement case, a Delaware judge has nullified the award and invalidated the patents behind the lawsuit involving AstraZeneca’s blockbuster lung cancer drug.
AstraZeneca on Wednesday was successful in reversing Pfizer’s previous legal victory in a patent tussle over the British-Swedish pharma’s cancer drug Tagrisso (osimertinib), with a Delaware judge nullifying the previous jury award and invalidating the patents in the lawsuit.
Delaware District Judge Matthew Kennelly’s decision reverses the previous $107.5 million in damages, which a federal jury awarded to Pfizer’s subsidiary Wyeth in May 2024. In his ruling against Pfizer, Kennelly agreed that the two Pfizer patents were invalid for lack of enablement, referring to a written description of the technologies in contention sufficient to instruct professionals capable of carrying out the inventions under contention.
Pfizer’s Wyeth unit sued AstraZeneca in 2021 claiming infringement of two key patents. The pharma alleged that AstraZeneca’s Tagrisso violates protections covering methods of using an EGFR blocker to treat non-small cell lung cancer (NSCLC) patients who are resistant to gefitinib and/or erlotinib.
Tagrisso also allegedly infringed on another patent that protected the use of irreversible EGFR inhibitors to treat gefitinib- or erlotinib-resistant NSCLC patients carrying a certain EGFR mutation, according to Pfizer. Both technologies are used by Wyeth’s and Puma Biotechnology’s Nerlynx (neratinib), which is indicated for HER2-positive breast cancer. The drug made more than $200 million in 2023.
In his ruling on Wednesday, Kennelly agreed with AstraZeneca that Pfizer failed to provide sufficient instruction that would otherwise have allowed a practitioner with requisite skills to carry out the invention in question.
“The Court concludes that AstraZeneca presented clear and convincing evidence such that no reasonable jury could find that the patents-in-suit enabled” a skilled practitioner “to administer a unit dosage of any irreversible EGFR inhibitor covered by the claims to a patient without undue experimentation,” Kennelly wrote.
The lack of enablement is crucial since “some dosages of compounds … specified by the patents-in-suit would be toxic to patients, and, more specifically, that the dosage level required for the compounds to be therapeutically effective could be unduly toxic to a patient,” according to Kennelly.
Tagrisso is a targeted treatment that blocks the activity of specific mutated forms of the EGFR protein, interfering with cancer cells’ growth and division. The FDA first approved Tagrisso in November 2015 for NSCLC patients with the T790M EGFR mutation. Tagrisso is one of AstraZeneca’s top-selling assets, raking in almost $5.8 billion in 2023.
