SWIPLit

By Anne Bolamperti and David G. Barker

The Federal Circuit invalidated Juno Therapeutics, Inc.’s T cell therapy patent for cancer treatment and erased a billion dollar judgment in Juno’s favor. The court held that the jury verdict regarding the patent’s written description under 35 U.S.C. § 112(a) was not supported by substantial evidence.

Juno’s U.S. Patent No. 7,446,190 (the “’190 patent”) relates to a nucleic acid polymer encoding a three-part chimeric antigen receptor (“CAR”) for a T cell. The first two portions of the CAR allow T cells to both kill target cells and divide into more T cells. The third portion of the CAR determines which target molecule or antigen the CAR can recognize and bind to. One type of the third portion of the CAR is called a single-chain antibody variable fragment (“scFv”). The ’190 patent discloses two scFvs, and one of the scFvs binds to a protein called CD19, which appears on the surface of prostate cancer cells. The ’190 patent does not disclose the amino acid sequence of either scFv.

Kite Pharma, Inc. developed YESCARTA, a cancer treatment containing a three-part CAR with an scFv that binds CD19. Juno sued Kite in the U.S. District Court for the Central District of California for infringing the ’190 patent. Kite counterclaimed seeking declaratory judgment of noninfringement and invalidity. After a two-week trial, the jury found that Kite willfully infringed the ’190 patent and failed to prove the asserted claims of the ’190 patent were invalid for lack of written description or enablement. The district court granted Juno’s motion for entry of judgment by increasing damages to nearly $800 million (reflecting updated YESCARTA revenues), awarding prejudgment interest, enhancing royalty damages by 50%, and awarding a 27.6% running royalty. Kite appealed.

In a precedential decision, the Federal Circuit held that the ’190 patent’s written description did not disclose sufficient information to show that the inventors possessed the claimed genus of functional CD19-specific scFvs. First, the panel found the written description did not include sufficient representative species because no particular amino acid sequence was disclosed that would identify the third portion of Juno’s claimed CAR that binds to CD19. Juno presented evidence that scFvs were generally known, but the panel found that even if scFvs were known and known to bind, the patent did not disclose a means of distinguishing which scFvs bind to which targets. Second, the panel found that Juno’s “general assertions” through expert testimony explaining scFvs have known structural commonalities and similarities did not rescue the ’190 patents failure to disclose structural features common to the members of the claimed genus.

In the end, the panel held that no reasonable jury could find that the ’190 patent satisfied the written description requirement. Few CD19-specific scFvs were known, even though a potentially high number might exist, and the ’190 patent did not specifically detail which scFvs bind to CD19 compared to those that do not. As a result, the Court reversed and vacated Juno’s $1.2 billion judgment.