As we previously reported, last month AbbVie filed a complaint against Boehringer Ingelheim (BI) in the U.S. District Court for the District of Delaware regarding BI’s aBLA for a biosimilar version of AbbVie’s Humira (adalimumab) product.

Yesterday, BI filed an answer to AbbVie’s complaint, which includes counterclaims against AbbVie for declarations of patent invalidity and non-infringement.  In support of its invalidity counterclaims, BI alleges that AbbVie “engaged in a pattern of pursuing numerous overlapping and non-inventive patents for the purpose of developing a ‘patent thicket,’ using the patenting process itself as a means to seek to delay competition against its expensive and lucrative adalimumab product. That strategy has generated, according to paragraph 18 of Plaintiffs’ complaint, more than 100 patents.”  BI further alleges that “many” of the 74 patents asserted in the litigation by AbbVie “share common specifications and have overlapping and nearly identical claims.”  BI asserts that these patents “do not represent innovation, but rather are attempts to claim methods of treatment, methods of production, and formulations derived from the prior art for the purpose of creating a patent thicket or estate that competitors must, as AbbVie has publicly stated, ‘contend with’ to sell the active ingredient” in Humira, which was covered by a patent that expired in December 2016.  BI also points to the fact that inter partes review proceedings before the PTO have already invalidated patents related to the patents asserted against BI in the suit.