April Breyer Menon, Corinne Atton and Ha Kung Wong reveal that PTAB decisions have been consistent but drug patents challenged multiple times are more likely to be found unpatentable.

There has been some concern regarding the statistics periodically issued by the Patent Trial and Appeal Board (“PTAB”) of the US Patent and Trademark Office, that the numbers reported overlook multiple inter partes review (“IPR”) challenges to the same patents, and potentially, different outcomes in those challenges. We have monitored IPRs filed on drug patents – patents that are listed in the Food and Drug Administration’s (FDA) Orange Book (“Orange Book patents”), and patents that have been identified in proceedings as reading on FDA Purple Book listed biologic drugs (“Biologic Drug Patents”) –  and report here that while certain drug patents have been challenged in multiple IPR petitions, concern as to different outcomes, at least in the final written decisions (“FWDs”) that have been issued to date, appears to be unfounded. These FWDs have been consistent: either all instituted claims have been held unpatentable, or all instituted claims have been held not unpatentable. The biggest news is that drug patents challenged in multiple IPRs – at least those that reach FWD – have a much greater chance of being found unpatentable than drug patents that have been challenged in only one IPR. The percentage is 63% for what we have described in this article as “duplicative FWDs”, compared to 44% for non-duplicative FWDs.

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Corinne Atton has experience litigating cases concerning a wide range of pharmaceuticals and biotechnology, including DNA sequences, DNA sequencing technologies, recombinant polypeptides, enzyme inhibitors, and antidiabetic drugs. Corinne has a B.Sc. honors degree in Human Genetics.
Ha Kung Wong has extensive experience litigating a wide variety of pharmaceutical cases, including those concerning biologics used to treat rheumatoid arthritis and autoimmune disorders. He also has extensive experience consulting, conducting due diligence and licensing pharmaceutical portfolios. Ha Kung has a B.S. in Biochemistry and a B.S. in Chemistry.
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    Information contained in the Venable BiologicsHQ database relates to FDA-approved drug products listed in the CDER Purple Book or on the FDA website ( Information relating to FDA licensed products, FDA-approved indications, and aBLA and 505(b)(2) applications is obtained from public sources including the U.S. FDA website ( Information relating to litigations is given only for cases active from January 31, 2010 onward. Information relating to foreign biosimilar / biologics follow-on products approved in Australia, Canada, the E.U., Japan and South Korea is from public sources. Statistics graphics are compiled from information contained in the Venable BiologicsHQ database.


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