Pfizer Gets Enanta Patent Voided in Case Over Paxlovid Royalties

Pfizer Inc. convinced a federal judge in Massachusetts to cancel a patent Enanta Pharmaceuticals Inc. alleges its blockbuster Covid-19 antiviral Paxlovid infringes.

Judge Denise J. Casper granted Pfizer’s cross-motion for summary judgment that US Patent No. 11,358,953 is invalid in an opinion issued Monday in the US District Court for the District of Massachusetts. She denied as moot Enanta’s bid for partial summary judgment of infringement and to exclude certain of Pfizer’s experts’ opinions.

• Enanta’s changes to the patent, which covers compounds and salts that inhibit coronavirus replication and methods of treating a coronavirus infection, “impermissibly broadened the scope such ...