Updates on Patent Challenges by Biosimilar Manufacturers at the PTAB

In the last month, there has been a flurry of activity at the PTAB related to challenges from biosimilar manufacturers related to ustekinumab, aflibercept, and eculizumab patents.

1. STELARA® (ustekinumab)

Four months after Janssen Biotech, Inc. settled to terminate Samsung Bioepis Co., Ltd.’s inter partes review (IPR) challenge of U.S. Patent No. 10,961,307 (“the ’307 Patent”), directed to methods of treating ulcerative colitis with ustekinumab, Biocon Biologics Inc. has filed its own IPR challenge to the ’307 Patent. Janssen is a subsidiary of Johnson & Johnson (“J&J”).  As we previously reported, J&J, Janssen Biotech’s parent company, has also entered into settlement agreements related to ustekinumab with Amgen; Alvotech and Teva; and Formycon and Fresenius Kabi.

2. EYLEA® (aflibercept)

In the midst of filing a second wave of BPCIA complaints against Formycon, Samsung, and Celltrion, Regeneron continues to defend its aflibercept patents on all fronts, as the PTAB instituted IPR of several of Regeneron’s patents while fielding new IPR challenges to the same.

As we previously reported, Samsung filed petitions for IPR of U.S. Patent No. 11,253,572 (“the ’572 Patent”), directed to methods of treating angiogenic eye disorders with aflibercept, and IPR of U.S. Patent No. 10,464,992 (“the ’992 Patent”), directed to vials comprising aflibercept formulations. Both patents are assigned to Regeneron Pharmaceuticals, Inc., and both are already facing IPR challenges from other manufacturers.

  • On November 17, 2023, the PTAB granted institution of Samsung’s petition for IPR of the ’572 Patent, finding that Samsung had demonstrated a reasonable likelihood that it would prevail in showing at least one challenged claim of the patent to be unpatentable. Samsung has now advanced further than Apotex Inc. did in its IPR challenge to the ’572 Patent, which was denied earlier this year.
  • On December 14, 2023, Celltrion, Inc. filed its own petition for IPR of the ‘572 patent, and a motion to join Samsung’s IPR proceeding against the ’572 Patent. Likewise, on December 18, 2023, Biocon filed a petition for IPR of the ‘572 patent, and a motion to join the same proceeding.
  • On December 8, 2023, the PTAB also granted institution of Samsung’s petition for IPR of the ’992 Patent and granted Samsung’s motion to join the proceeding with Celltrion, Inc.’s IPR of the same patent which was instituted in July.  As we previously reported, Regeneron filed a complaint on November 8, 2023 against Celltrion alleging infringement of, inter alia, the ’992 Patent.

On October 20, 2023, the PTAB instituted Samsung’s petition for IPR of U.S. Patent No. 10,888,601 (“the ’601 Patent”), challenging claims directed to methods of treating diabetic macular edema (“DME”) and diabetic retinopathy (“DR”).

  • On November 20, 2023, Biocon filed its own IPR petition challenging the same claims.
  • As we previously reported, Mylan (and Biocon as its successor-in-interest), Celltrion, and Samsung have already challenged claims of the ’601 patent directed to treatment of age-related macular degeneration (“AMD”).  The PTAB instituted that IPR in January 2023 and heard oral argument in October 2023.  A Final Written Decision is expected in January 2024.

3. SOLIRIS® (eculizumab)

As we previously reported, earlier this year, Samsung filed IPR petitions for five U.S. patents assigned to Alexion Pharmaceuticals, Inc. and relating to eculizumab compositions for the treatment of paroxysmal nocturnal hemoglobinuria (PNH). The PTAB recently granted institution of each of the five petitions. On December 8, 2023, the PTAB granted Samsung’s petitions for IPR of U.S. Patent Nos. 9,732,149; 9,718,880; and 9,725,504.  On December 19, 2023, the PTAB granted Samsung’s petition for IPR of U.S. Patent No. 10,703,809.  And on December 20, 2023, the PTAB granted Samsung’s petition for IPR of U.S. Patent No. 10,590,189.