PTAB Updates: Trastuzumab, Rituximab, Filgrastim, Pegfilgrastim, Insulin Glargine

Below is a summary of recent updates in biosimilar-related proceedings before the Patent Trial and Appeal Board of the United States Patent and Trademark Office.

Trastuzumab:

Last month, the Board issued two Final Written Decisions in IPRs of U.S. Patent No. 7,892,549, which is directed to methods for the treatment of breast cancer that overexpresses the ErbB2 receptor.  First, in IPR2017-00737, filed by Hospira and joined by Samsung Bioepis, the Board found unpatentable all 17 claims of the ’549 patent.  Similarly, in IPR2017-01122, filed by Celltrion, the Board found unpatentable claims 1–11 and 14–17 of the ’549 patent (i.e., all claims challenged by Celltrion).  The Board also denied Genetech’s motion to amend the ‘549 patent.

The Board also issued two Final Written Decisions in IPRs of U.S. Patent No. 7,846,441, which is related to the ’549 patent. In each of IPR2017-00731, filed by Hospira, and IPR2017-01121, filed by Celltrion and joined by Pfizer, the Board found unpatentable all 14 originally issued claims of the ’441 patent. The Board also denied Genetech’s motion to amend the ‘441 patent.

In addition, the Board issued Final Written Decisions in IPRs of U.S. Patent Nos. 6,627,196 and 7,371,379. Both patents are directed to methods of treatment for cancer using a specific dosing regimen.  First, in IPR2017-00804 and IPR2017-00805, the Board found that petitioner Hospira (joined by Samsung Bioepis) had failed to show that claims 1–3, 5, 7, 9–11, and 17–33 of the ’196 patent and claims 1–3, 5, 7, 9–11, 16–28, and 30–40 of the ’379 patent were unpatentable.  The Board also issued Final Written Decisions in IPR2017-01139 and IPR2017-01140, both filed by Celltrion, respectively finding that claims 1–3, 5, 7, 9–11, 13–15, and 17–33 of the ’196 patent and claims 1–3, 5, 7, 9–11, 13–28, and 30–40 of the ’379 patent were not shown to be unpatentable.

Genentech has asserted all four of these patents, among others, in its BPCIA litigations against Pfizer, Celltrion & Teva, Amgen and Samsung Bioepis, which are pending and being coordinated with one another in the United States District Court for the District of Delaware before Judge Connolly.  Most recently, on November 1, 2018, the court entered a scheduling order that calls for a 9-day bench trial beginning on December 9, 2019.

Rituximab:

Last month, the Board issued a Final Written Decision in IPR2017-01095 filed by Celltrion, finding unpatentable claims 1–6 of U.S. Patent No. 9,296,821, which is directed to combined therapeutic regimens using anti-CD20 antibodies for the treatment of lymphomas. Then, last week, Pfizer and Biogen filed a joint motion to terminate Pfizer’s IPR2018-00186 of this same patent.

Last week the Board also issued a Final Written Decision in IPR2017-01168, filed by Pfizer, finding unpatentable all claims of U.S. Patent No. 8,821,873, which is directed to a method of treating lymphoma with anti-CD20 antibodies.

These patents, among others, have been asserted in BPCIA litigations against Celltrion & Teva and Sandoz regarding proposed biosimilars of Rituxan® (rituximab).  As we recently reported, Genentech and co-plaintiffs reached a settlement with defendants Celltrion and Teva, and the suit has been dismissed.  Last week, in the ongoing dispute between Genentech and Sandoz, Sandoz requested that the Court stay all remaining case deadlines in view of its recent decision not to pursue its FDA submission for this product.  While the Court rejected Sandoz’s request for a stay, the Court agreed to extend Sandoz’s imminent deadline to submit non-infringement contentions to allow the parties additional time to prepare a proposed stipulation of dismissal.

Filgrastim/Pegfilgrastim:

Last month, Adello Biologics and Apotex jointly filed a petition for Post-Grant Review (PGR) of U.S. Patent No. 9,856,287 (PGR2019-00001), which is directed to a protein refolding method.  Amgen has asserted the ’287 patent in its BPCIA litigation against Adello concerning its proposed biosimilar of Neupogen® (filgrastim) and in its second-wave litigation against Apotex regarding its proposed biosimilars referencing Neupogen® (filgrastim) and Neulasta® (pegfilgrastim).

Insulin Glargine:

As we previously reported, in September 2018 Mylan filed three IPR petitions (IPR2018-01677IPR2018-01678 and IPR2018-01696) challenging U.S. Patent No. 8,992,486, which Sanofi-Aventis is asserting in a patent infringement suit against Mylan regarding its proposed follow-on product referencing Sanofi-Aventis’ Lantus® (insulin glargine injection).  Last month, Mylan filed a fourth IPR petition (IPR2019-00122) against the ’486 patent.