Case 2:20-cv-00337-JRG Document 1 Filed 10/19/20 Page 1 of 13 PageID #: 1
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`UNITED STATES DISTRICT COURT
`EASTERN DISTRICT OF TEXAS
`MARSHALL DIVISION
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`CIVIL ACTION NO.
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`SEAGEN INC.,
`
`Plaintiff,
`
`v.
`DAIICHI SANKYO CO., LTD.,
`Defendant.
`
`
`
`COMPLAINT FOR PATENT
`INFRINGEMENT
`JURY TRIAL DEMANDED
`
`COMPLAINT
`
`Plaintiff Seagen Inc. (“Seagen”) complains and alleges as follows against Defendant
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`Daiichi Sankyo Co., Ltd. (“DSC”).
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`THE NATURE OF THE ACTION
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`1.
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`Seagen brings this action to protect its proprietary technology enabling the
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`delivery of chemotherapeutic drugs directly to cancer cells. When Seagen began developing
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`this technology, most chemotherapeutic drugs for cancer were not targeted, resulting in the
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`delivery of treatments throughout the patient’s body and causing significant adverse side
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`effects. Since then, Seagen’s pioneering innovations in the field of antibody-drug
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`conjugates (ADCs), a type of therapy that directly targets chemotherapeutic drugs to cancer
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`cells, have helped establish ADCs as an important pillar of cancer therapy. Seagen’s ADC
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`technology is the result of decades of research and development effort by Seagen’s
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`scientists and hundreds of millions of dollars of investment. Seagen’s transformative
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`innovations have maintained Seagen’s leadership status even as other companies have
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`entered the field, and Seagen’s innovations are embodied in more approved ADC therapies
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`than those of any other company. DSC is a new entrant in the ADC field, and it infringes
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`Seagen’s United States Patent No. 10,808,039 (the “’039 patent”). DSC has already booked
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`tens of millions of dollars in sales of an infringing product, and appears intent upon
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`expanding its infringing activities.
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`2.
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`ADCs are specialized cancer treatments that use a “linker” to attach (or
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`“conjugate”) chemotherapeutic drugs to an antibody. The antibody in an ADC targets
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`receptors on the surface of a cancer cell. The targeted cell then internalizes the ADC,
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`releasing the ADC’s chemotherapeutic drug to kill the cancer cell. This technology is
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`cutting edge. To date, only nine ADCs have been approved by the FDA.
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`3.
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`After its founding in 1998, Seagen pioneered a class of linkers with a
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`cleavable amino acid unit for use in ADCs. This class is often referred to as “protease
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`cleavable” because specialized enzymes within the cell called “proteases” cleave the bonds
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`of the amino acid unit to release the drug. After more than ten years of fundamental
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`research, Seagen received FDA approval for its first ADC employing this technology,
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`ADCETRIS®, in 2011. Of the nine, now-approved ADCs, more use Seagen’s linker
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`technologies than any other.
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`4.
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`All of the products in DSC’s ADC pipeline also use a protease cleavable
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`linker that is covered by the claims of Seagen’s ’039 patent. The currently accused product
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`is DSC’s DS-8201 ADC (now branded ENHERTU®), the first ADC in DSC’s pipeline to be
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`FDA approved. On January 6, 2020, DSC announced DS-8201’s availability in the United
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`States, noting that DSC would be solely responsible for manufacturing and supply. DSC
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`causes DS-8201 to be imported into, offered for sale, sold, and used in the United States.
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`DSC also ultimately books the United States sales of DS-8201, and these sales have totaled
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`more than $70 million to date.
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`5.
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`DSC may seek FDA approval for its other pipeline products covered by the
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`claims of the ’039 patent, including U3-1402, DS-1062, DS-7300, DS-6157, in the near
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`future. Seagen intends by this Complaint that these products also be accused products
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`should Seagen learn during the course of discovery that DSC has engaged in infringing
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`activities as to these products.
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`THE PARTIES
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`6.
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`Plaintiff Seagen is a biotechnology company formerly known as Seattle
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`Genetics, Inc. Seagen develops and commercializes transformative therapies targeting
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`cancer. Seagen is headquartered in Bothell, Washington, and incorporated under the laws of
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`Delaware.
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`7.
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`Defendant DSC is a Japanese pharmaceutical corporation having its principal
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`place of business at 3-5-1, Nihonbashi Honchō, Chūo-ku, Tokyo 103-8426, Japan.
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`JURISDICTION AND VENUE
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`8.
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`This Court has subject matter jurisdiction under 28 U.S.C. 1331 and under 28
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`U.S.C. § 1400(b).
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`9.
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`This Court has personal jurisdiction over DSC, as DSC conducts business and
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`has committed acts of patent infringement, induced acts of patent infringement, and
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`contributed to patent infringement in the United States, the State of Texas, and the Eastern
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`District of Texas.
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`10. DSC also has sufficient minimum contacts with the forum as a result of
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`business it conducts within Texas and this district. DSC—directly or through subsidiaries
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`or intermediaries including distributors, retailers, and others—offers for sale, and sells (as
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`well distributes, advertises, and markets) products, including DS-8201, that infringe the
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`’039 patent throughout Texas and this district. For example, DSC owns the U.S.
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`registration for the ENHERTU® trademark for DS-8201. DSC acts in concert with others
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`to purposefully and voluntarily place the infringing products in a distribution chain that
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`foreseeably leads to the infringing products being offered for sale, sold, and used in Texas
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`and this district as part of the ordinary stream of commerce. DSC has done so with the
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`expectation that these infringing products have been, and will continue to be, purchased in
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`Texas and this district and that such purchases be part of the ordinary stream of commerce.
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`11.
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`In addition, DSC’s subsidiaries and contractual business partners have
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`operated as agents of DSC as parts of a business group in which executives of DSC make
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`important operational decisions regarding the manufacture, importation, offer for sale, sale,
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`and intended use of the infringing products, including DS-8201. Through these agents, DSC
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`has conducted business and committed acts of infringement in the United States, Texas, and
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`this district.
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`12. Alternatively, to the extent that DSC is not subject to jurisdiction in any state
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`court of general jurisdiction, this Court may exercise jurisdiction over DSC pursuant to
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`Federal Rule of Civil Procedure 4(k)(2) because: (a) Seagen’s claims arise under federal
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`law; and (b) DSC has sufficient contacts with the United States as a whole, including but
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`not limited to manufacturing the infringing products and importing them into the United
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`States and offering for sale, selling, and causing them to be sold in the United States, such
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`that this Court’s exercise of jurisdiction over DSC satisfies due process.
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`13. Venue is proper in this judicial district pursuant to 28 U.S.C. § 1400(b) and
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`28 U.S.C. § 1391(c). DSC is a foreign corporation and may be sued in this district. Venue
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`is further proper because DSC has committed acts of infringement in this district, and has
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`purposely transacted business involving the infringing products in this district.
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`PATENT-IN-SUIT – U.S. PATENT NO. 10,808,039
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`14.
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`Seagen is the sole owner of the ’039 patent and holds the sole right to enforce
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`it. The ’039 patent claims priority to provisional applications filed on November 6, 2003,
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`and March 26, August 4, and October 27, 2004. The inventors were all employees of
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`Seagen at the time the priority applications were filed. Although the ’039 patent issued
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`recently, DSC has been aware of one or more parent applications of the ’039 patent since at
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`least 2008, and it has been aware of the specific application that issued as the ’039 patent
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`since at least June of this year. DSC also has notice of the ’039 patent from the filing of this
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`Complaint.
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`15.
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`The ’039 patent claims technologies associated with ADCs. At the time of
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`the invention, most therapeutics administered to patients to treat cancer—such as
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`chemotherapeutic drugs—were not targeted to cancer cells, resulting in systemic delivery of
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`the therapeutics to cells and tissues of the body, including to healthy cells where they are
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`unnecessary, often undesirable, and can cause considerable adverse side effects. In the late
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`1990s, custom designed antibodies were developed as targeted agents for the treatment of
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`cancer and certain autoimmune diseases, but they, too, had limitations. Combining these
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`antibodies with chemotherapy drugs to deliver them in a targeted fashion was under
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`investigation as a next-generation technology, and chemotherapeutic drugs that bind tubulin
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`(an important protein for cell division), bind DNA, or inhibit topoisomerases (enzymes
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`involved in DNA replication and transcription) were known to be leading candidates. But
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`linkers that would release drugs only in the target cells proved elusive. The first ADC to
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`reach the market had to be withdrawn due to off-target effects thought to be caused by an
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`unstable linker that disassociated before the ADC reached the intended target.
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`16.
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`Seagen’s path-breaking work led to the development of protease-cleavable
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`ADC linkers that were more stable (and thus more likely to deliver chemotherapeutic drugs
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`to target cancer cells) than other linker types, and included research on a range of amino
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`acid motifs that could be used in such linkers. Seagen also developed more predictable
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`“cysteine” conjugation technology (technology which differs from the “lysine” conjugation
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`technology favored by other companies), and technology for arriving at a desired
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`drug-to-antibody ratio or “DAR” (a term that refers to the number of drug units linked to
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`each antibody).
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`DEFENDANT’S INFRINGEMENT
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`17.
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`The claims of the ’039 patent are directed to antibody-drug conjugates
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`comprising a protease cleavable linker of four amino acids in length, wherein each amino
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`acid is either glycine or phenylalanine. The ’039 patent is enforceable and valid, and DSC’s
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`ADC products fall within the scope of the patent rights provided by the claims of the ’039
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`patent.
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`18.
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`The claims of the ’039 patent cover ADCs with linkers having the formula –
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`Aa—Ww—Yy–, wherein Aa is a stretcher unit that bonds to a sulfur atom of the amino acid
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`cysteine in the antibody, Ww is an amino acid unit, and Yy is a spacer unit between the
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`amino acid unit and the drug. Independent claim 1 provides that the stretcher unit Aa is the
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`maleimide maleimidocaproyl, or “mc,” as shown in the diagram below.
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`19.
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`Claim 1 further provides that the amino acid unit Ww is a tetrapeptide of four
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`amino acids in length, with each amino acid having the formula shown below in which R19
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`is either hydrogen (i.e., the amino acid glycine, or “G”) or benzyl (i.e., the amino acid
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`phenylalanine, or “F”):
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`20.
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`Claim 4, which includes the limitations of claims 1, 2, and 3, and the claims
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`that depend from claim 4, are exemplary on the issue of infringement. DSC’s ADCs with
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`this linker infringe Claim 4 because they comprise a maleimidocaproyl stretcher unit that
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`bonds to a sulfur atom of the amino acid cysteine in the antibody, a tetrapeptide amino acid
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`unit with the amino acid motif GGFG, and a self-immolative spacer unit. The
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`drug-to-antibody ratio for these ADCs is about 3 to about 8. The chart below provides more
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`detail regarding how DS-8201 infringes claim 4. U3-1402, DS-1062, DS-7300, DS-6157 all
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`use the same linker as DS-8201.
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`DS-8201
`DS-8201 is an antibody-drug conjugate. In
`DS-8201, the payload drug is conjugated to
`the antibody using a linker that has the
`claimed formula, including a stretcher unit
`mc, an amino acid unit Ww with the
`tetrapeptide motif GGFG, and an
`aminomethylene spacer unit Yy:
`
`Claim 4
`1. An antibody-drug conjugate having the
`formula:
`
`O
`
`Ww Yy D
`
`p
`
`
`
`NO
`
`O
`
`Ab
`
`S
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`or a pharmaceutically acceptable salt
`thereof, wherein:
`
`
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`In DS-8201, the antibody to which drugs
`are conjugated is trastuzumab.
`
`In DS-8201, the linker’s stretcher unit mc
`bonds to sulfur atoms on cysteine residues
`of the antibody.
`
`In DS-8201, the linker has an amino acid
`unit with the tetrapeptide motif GGFG.
`Glycine, or G, corresponds with the
`claimed amino acid formula wherein R19 is
`hydrogen. Phenylalanine, or F, corresponds
`with the claimed amino acid formula
`wherein R19 is benzyl.
`
`In DS-8201, the linker has an
`aminomethylene spacer unit.
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`Ab is an antibody,
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`S is sulfur,
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`each -Ww - unit is a tetrapeptide; wherein each
`–W– unit is independently an Amino Acid
`unit having the formula denoted below in the
`square bracket:
`
`O
`
`HN
`
`R19
`, wherein R19 is hydrogen or benzyl,
`
`Y is a Spacer unit,
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`y is 0, 1 or 2,
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`In DS-8201, there is one spacer, so y is 1.
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`D is a drug moiety, and
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`p ranges from 1 to about 20, and
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`wherein the S is a sulfur atom on a cysteine
`residue of the antibody, and
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`wherein the drug moiety is intracellularly
`cleaved in a patient from the antibody of
`the antibody-drug conjugate or an
`intracellular metabolite of the antibody-
`drug conjugate.
`
`In DS-8201, the drug that is conjugated to
`the antibody with the linker is the
`camptothecin derivative DXd, which acts as
`a topoisomerase inhibitor.
`
`In DS-8201, the value of p, which
`represents drug loading in terms of the
`drug-to-antibody ratio or “DAR”, is about
`7.7.
`
`In DS-8201, the linker’s stretcher unit mc
`bonds to sulfur atoms on cysteine residues
`of the antibody.
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`DS-8201’s linker is cleaved within the cell
`by proteases to release the camptothecin
`derivative drug DXd.
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`2. The antibody-drug conjugate of claim 1,
`wherein Y is a self-immolative spacer.
`
`In DS-8201, the linker’s aminomethylene
`spacer unit is self-immolative.
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`3. The antibody-drug conjugate of claim 2,
`wherein y is 1.
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`4. The antibody-drug conjugate of claim 3,
`wherein p is about 3 to about 8.
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`In DS-8201, there is one spacer, so y is 1.
`
`In DS-8201, the value of p, which
`represents drug loading in terms of the
`drug-to-antibody ration or “DAR”, is about
`7.7.
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`COUNT I: ENFORCEMENT OF U.S. PATENT NO. 10,808,039 AS TO ACTS OF
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`INFRINGEMENT BY DEFENDANT
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`21.
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`Seagen hereby restates and re-alleges the allegations set forth in paragraphs 1
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`through 20 above and incorporates them by reference.
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`22. DSC has been and is now directly infringing, contributing to infringement,
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`and inducing others to infringe the ’039 patent in this district and elsewhere in violation of
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`35 U.S.C. § 271 at least by making, using, selling, offering to sell, and importing into the
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`United States ADC products, including DS-8201, that meet the limitations of one or more
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`claims of the ’039 patent.
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`23. DSC has committed infringing acts without the permission, consent,
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`authorization, or license of Seagen.
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`24. DSC’s infringement is literal or under the doctrine of equivalents, or both.
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`25. DSC, in addition to its own direct infringement, is currently actively inducing
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`and encouraging infringement of the ’039 patent, and will continue to actively induce and
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`encourage infringement of the ’039 patent. DSC has known of the ’039 patent at least since
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`the time of Seagen’s transmittal of this Complaint to DSC, and had prior knowledge of the
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`application from which it issued. DSC nevertheless actively encourages others to infringe
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`the ’039 patent such as by promoting and encouraging the use of the infringing products,
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`including DS-8201. DSC knowingly induces infringement by others, including importers,
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`manufacturers, sellers, and users of the infringing products, including DS-8201. These facts
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`give rise to a reasonable inference that DSC knowingly induces others, including importers,
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`manufacturers, sellers, and users, to directly infringe the ’039 patent, and that DSC
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`possesses a specific intent to cause such infringement. Importers, manufacturers, sellers,
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`and users of the infringing products directly infringe the ’039 patent.
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`26. DSC also contributes to infringement of the ’039 patent by manufacturing,
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`offering to sell, or selling within the United States or importing into the United States
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`components of the infringing products, including linkers such as those found in DS-8201,
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`while having knowledge of the ’039 patent and knowledge that these components are
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`especially made or especially adapted for use in products that infringe the ’039 patent.
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`These components are not staple articles or commodities of commerce suitable for
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`substantial noninfringing uses. Importers, manufacturers, sellers, and users of the infringing
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`products including these components directly infringe the ’039 patent.
`
`27.
`
` DSC’s infringement has been willful. DSC had knowledge of the parent
`
`applications of the ’039 patent, including the application that issued as the ’039 patent and
`
`its published claims, before the filing of this Complaint. DSC has proceeded to make, use,
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`offer for sale, sell, and import the infringing products, including DS-8201, despite knowing
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`that the products would infringe the ’039 patent, and DSC have continued to make, use,
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`offer for sale, sell, and import the infringing products, including DS-8201, since the filing of
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`this Complaint. DSC was also generally aware of Seagen’s linker technology, inquired
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`about it, and directly compared it to the linkers in DSC’s infringing products, including
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`DS-8201, in articles, analyses, and presentations. For these and other reasons, DSC’s
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`infringing acts have been egregious.
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`28. As a direct and proximate result of DSC’s infringement of the ’039 patent,
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`Seagen has suffered, and will continue to suffer damages, including lost profits.
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`29.
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`Seagen has also suffered damages from DSC’s infringement of Seagen’s
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`provisional rights in the ’039 patent, as DSC was on notice of the published patent
`
`application for the ’039 patent and the issued claims are substantially identical to claims in
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`the published application.
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`PRAYER FOR RELIEF
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`WHEREFORE, Seagen respectfully requests the following relief:
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`a.
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`Judgment in Seagen’s favor against DSC that DSC infringed one or more valid
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`and enforceable claims of the ’039 patent;
`
`b.
`
`c.
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`A finding that DSC’s infringement was willful;
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`An award of damages to Seagen in an amount to be proven at trial, including lost
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`profits but in no event less than a reasonable royalty, as well as pre-judgment and post-judgment
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`interest at the maximum rate permitted by law;
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`d.
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`An award of attorney fees and enhancement of any damages by virtue of the
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`exceptional nature of this case under 35 U.S.C. § 285;
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`e.
`
`f.
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`A running royalty; and
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`Such other relief as the Court deems just and proper.
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`DEMAND FOR JURY TRIAL
`
`Seagen hereby demands trial by jury of all claims and issues so triable presented in this
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`Complaint.
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`Dated: October 19, 2020 CT
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`(October 20, 2020 ET)
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`
`By: /s/ Melissa R. Smith
`Michael A. Jacobs (pro hac vice pending)
`MJacobs@mofo.com
`Matthew A. Chivvis (pro hac vice pending)
`MChivvis@mofo.com
`MORRISON & FOERSTER LLP
`425 Market Street
`San Francisco, CA 94105
`Telephone: 415.268.7000
`Facsimile: 415.268.7522
`
`Bryan Wilson (pro hac vice pending)
`BWilson@mofo.com
`Pieter S. de Ganon (pro hac vice pending)
`PdeGanon@mofo.com
`MORRISON & FOERSTER LLP
`755 Page Mill Road
`Palo Alto, California 94304-1018
`Telephone: 650.813.5600
`Facsimile: 650.494.0792
`
`Melissa R. Smith
`Texas State Bar No. 24001351
`melissa@gillamsmithlaw.com
`GILLAM & SMITH, LLP
`303 South Washington Avenue
`Marshall, Texas 75670
`Telephone: 903.934.8450
`Facsimile: 903.934.9257
`
`Of Counsel:
`
`T. John Ward, Jr.
`Texas State Bar No. 00794818
`jw@wsfirm.com
`Charles Everingham IV
`Texas State Bar No. 00787447
`ce@wsfirm.com
`Andrea L. Fair
`Texas State Bar No. 24078488
`andrea@wsfirm.com
`WARD, SMITH & HILL, PLLC
`1507 Bill Owens Parkway
`Longview, Texas 75604
`Telephone: 903.757.6400
`Facsimile: 903.757.2323
`Attorneys for Plaintiff Seagen Inc.
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