On March 21, 2017, Celltrion, Inc. (“Celltrion”) filed two new petitions for inter partes review (“IPR”) of U.S. Patent Nos. 7,846,441 (“the ’441 patent”) and 7,892,549 (“the ’549 patent”). Three days later, on March 24, 2017, Celltrion filed two additional IPR petitions for U.S. Patent Nos. 6,626,196 (“the ‘196 patent”) and 7,371,379 (“the ‘379 patent”).  All four of these patents are related to Genentech’s Herceptin® (trastuzumab). Last month, Celltrion filed a petition with the Patent Trial and Appeal Board (“PTAB”) challenging certain claims of Genentech’s Patent No. 8,591,897, which is also related to Herceptin® as reported in this post.

Celltrion announced that its trastuzumab application had been received for review by the European Medicines Agency (“EMA”) in October of last year, and the company is planning to submit an application to the FDA during the first half of 2017.

Trastuzumab is a monoclonal antibody that interferes with the human epidermal growth factor receptor (HER2)/neu. Herceptin® is indicated for the treatment of patients with metastatic breast cancer whose tumors overexpress the HER2 protein and who have received one or more chemotherapy regimens for their metastatic disease.

The proceedings are IPR2017-01121 (involving the ’441 patent); IPR2017-01122 (involving the ‘549 patent); IPR2017-01139 (involving the ‘196 patent); and IPR2017-01140 (involving the ‘379 patent). The real parties-in-interest identified for Petitioner are Celltrion, Inc., Celltrion Healthcare Co. Ltd., and Teva Pharmaceuticals International GmbH.

The challenged claims of the ’441 patent are directed to a method of treating cancers linked to the overexpression of the human ErbB2 protein by administering an anti-ErbB2 antibody that binds to epitope 4D5 and a taxoid chemotherapeutic agent in the absence of an anthracycline derivative.  The challenged claims of the ’549 patent are directed to a method of treating cancers characterized by the overexpression of ErbB2 by administering a combination of an anti-ErbB2 antibody, a taxoid chemotherapeutic agent, and another therapeutic agent which may be another antibody, a growth inhibitory agent, or a cytokine.  The challenged claims of the ’196 and ’379 patents are generally directed to methods of treating cancers characterized by the overexpression of ErbB2 by administering an effective amount of an anti-ErbB2 antibody using a dosage regimen that provides a large initial dose, followed by the subsequent administration of additional dosages in amounts that are the same as or less than the initial dosage spaced two to three weeks apart (referred to in the specification as “front loading”).  Hospira has also filed IPR petitions challenging claims of the ’441, ’549, ‘196 and ‘379 patents, as we reported here in January 2017.

Hospira  filed a petition on which trial has been instituted at the PTAB on a fifth patent related to Herceptin® (as reported here). A complete list of IPRs related to trastuzumab and other proposed biosimilar products can be found in RFEM’s IPR Dashboard.

Mylan is also seeking approval of a trastuzumab biosimilar. Mylan recently withdrew two IPR petitions and announced that Mylan and Biocon have reached a global settlement and licensing agreement with Genentech and Roche regarding Mylan’s trastuzmab biosimilar as discussed in this post.