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ARTICLE · 22 APRIL 2022

Does PTAB's Ex Parte Cellect Decision Endanger Biopharmaceutical Patent Terms?

Mayer Brown
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In a warning to patent owners, a patent whose term had been extended through Patent Term Adjustment ("PTA") was recently found invalid for obviousness-type double patenting ("ODP") by the...

United StatesIntellectual Property
Scott A. McMurry
Scott A. McMurry
Ryan Babcock
Ryan Babcock
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In a warning to patent owners, a patent whose term had been extended through Patent Term Adjustment (“PTA”) was recently found invalid for obviousness-type double patenting (“ODP”) by the US Patent Trial and Appeal Board (“PTAB”). Ex Parte Cellect Patent Owner and Appellant, Appeal No. 2021-00503, 2021 WL 5755329 (PTAB, Dec. 1, 2021). This is particularly concerning for makers of biopharmaceuticals, especially immunotherapeutic proteins and other biologic drugs. The duration of the patents protecting these drugs is critical to their value, and the terms of these patents are often extended by PTA. Moreover, effective lifecycle management strategies for immunotherapeutics typically involve developing broad, independent patent portfolios (often covering new or extended medical indications), increasing the risk of generating potentially invalidating ODP art.

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