A Fox Rothschild team, led by Howard S. Suh, Joe Chen Ph.D., Ryan N. Miller and Erxin Du, won a complete victory for CSPC Megalith Biopharmaceutical Co., Ltd. before the Patent Trial and Appeal Board in a dispute involving a particular approach to cancer therapy.

The board invalidated each of the 23 claims of Lepu Biopharma’s U.S. Patent No. 10,792,370 (the ’370 patent) that CPSC Megalith challenged. In its Final Written Decision issued Oct. 8, 2026, in CSPC Megalith Biopharmaceutical Co. v. Lepu Biopharma Co., IPR2025-00685, the Board held all the challenged claims unpatentable.

The ’370 patent covers an antibody-drug conjugate (ADC) that targets the epidermal growth factor receptor (EGFR), a well-established target in cancer therapy. In the claimed ADC, a specific humanized antibody, BA03, is attached to a cytotoxic drug through a cleavable linker. Our team showed that this combination came straight out of the prior art: a known humanized version of cetuximab paired with an off-the-shelf vc-MMAE linker-drug platform.

The board found all claims obvious under both grounds we presented and adopted our petition’s positions as its findings of fact. It rejected each of the patent owner’s arguments, calling the patent owner’s central theory a “strawman.” It also found that the patent owner’s evidence of objective indicia of non-obviousness was not enough to overcome the strong showing of obviousness.

The board instituted trial in October 2025 and heard oral argument on July 15, 2026, where Howard Suh and Joe Chen presented for CSPC Megalith. Throughout the proceeding, the team built a record that gave the board clear documentary grounds for its ruling.

The win clears a significant patent obstacle for our client’s anti-EGFR ADC work and adds to the firm’s record in life sciences PTAB practice.

As this article contains statements regarding past performance, please note that results may vary depending on your particular facts and legal circumstances.