Pfizer Launches Its Own Challenge to Genentech’s Herceptin Patent, Following Celltrion, Mylan

Following two other firms, Pfizer filed its own petitions with the PTO over a Herceptin patent owned by Genentech, as it continues to develop its biosimilar.

The challenge follows requests from South Korean biosimilars firm Celltrion last month for an inter partes review by the office’s Patent and Trial Appeals Board on the same patent for the blockbuster cancer treatment.

In worldwide sales last year, Herceptin (trastuzumab) raised $6.77 billion for Genentech and its parent company, Roche. The patent covers methods for producing antibodies related to the drug.

Pfizer and Celltrion said a trained professional at the time would have been aware of journal articles and scientific papers detailing methods for making the antibodies — derived from mouse and non-human cell lines — more tolerable by the human immune system, allowing their use as a medicine.