323 F. Supp. 3d 1042
S.D. Ind.2018Background
- Lilly owns U.S. Patent No. 7,772,209 covering a method of administering pemetrexed disodium with folic acid and vitamin B12 to reduce chemotherapy toxicity (ALIMTA®).
- Dr. Reddy's submitted an NDA for a competing pemetrexed product formulated as pemetrexed ditromethamine and proposed label instructions for the same vitamin pretreatment regimen.
- The dispute centers on claim 12 (a liquid administration method) and whether Dr. Reddy's salt form is equivalent to the claimed pemetrexed disodium.
- Chemically, disodium and ditromethamine salts differ in counterions, hygroscopicity, pH/buffering behavior, and solid-state properties, but both dissociate in aqueous solution to the same active pemetrexed ion.
- Court previously construed claim 12 to require liquid (solution) administration; the person of skill in the art (POSA) for this claim was found to be a medical oncologist (not a chemist).
- Trial focused on prosecution-history estoppel, disclosure-dedication, doctrine of equivalents (insubstantial differences test), and inducement/contributory infringement based on Dr. Reddy's label.
Issues
| Issue | Plaintiff's Argument (Lilly) | Defendant's Argument (Dr. Reddy's) | Held |
|---|---|---|---|
| Prosecution-history estoppel — did narrowing to disodium surrender ditromethamine equivalents? | Lilly: amendment was tangential to the equivalent (narrowed to avoid Arsenyan), so estoppel does not bar DOE claim. | Dr. Reddy's: narrowing shows surrender; patentee could have drafted broader claim. | Held: Amendment was tangential; Lilly rebutted presumption of estoppel. |
| Disclosure-dedication — did specification or cited prior art dedicate ditromethamine to the public? | Lilly: Akimoto reference is generic and does not specifically disclose pemetrexed ditromethamine; no dedication. | Dr. Reddy's: Akimoto (and "pharmaceutically acceptable salts") discloses salts including tromethamine, so dedication. | Held: No dedication — reference was not specific enough to dedicate pemetrexed ditromethamine. |
| Doctrine of equivalents — are differences between salts insubstantial for the claimed liquid administration? | Lilly: In solution both salts yield identical pemetrexed ions; differences in solid-state/chemistry are irrelevant to the method of liquid administration; POSA is an oncologist. | Dr. Reddy's: Chemical/biochemical differences matter; POSA should be a chemist evaluating salt interchangeability. | Held: Differences are insubstantial in context; salts are equivalent for the claimed liquid administration; POSA is an oncologist. |
| Inducement / contributory infringement — does Dr. Reddy's label create liability? | Lilly: Label instructs the patented pretreatment regimen; intent can be inferred from labeling; no substantial noninfringing use. | Dr. Reddy's: Good-faith belief of noninfringement; lacked specific intent/knowledge post-Commil. | Held: Label would inevitably lead some physicians to perform the patented method; specific intent and contributory infringement inferred; Dr. Reddy's liable for inducement and contribution. |
Key Cases Cited
- Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., 535 U.S. 722 (2002) (prosecution-history estoppel framework and tangentiality exception)
- Warner-Jenkinson Co. v. Hilton Davis Chem. Co., 520 U.S. 17 (1997) (DOE and POSA context for equivalence analysis)
- Graver Tank & Mfg. Co. v. Linde Air Prod. Co., 339 U.S. 605 (1950) (function-way-result and insubstantial differences tests for equivalence)
- Mylan Institutional LLC v. Aurobindo Pharma Ltd., 857 F.3d 858 (Fed. Cir. 2017) (guidance on equivalence tests and chemical cases)
- Boehringer Ingelheim Vetmedica, Inc. v. Schering-Plough Corp., 320 F.3d 1339 (Fed. Cir. 2003) (insubstantial differences standard)
- AstraZeneca LP v. Apotex, Inc., 633 F.3d 1042 (Fed. Cir. 2010) (labeling can show intent to induce infringement)
- Commil USA, LLC v. Cisco Sys., Inc., 135 S. Ct. 1920 (2015) (knowledge and intent considerations in inducement)
- SanDisk Corp. v. Kingston Technology Co., Inc., 695 F.3d 1348 (Fed. Cir. 2012) (limits of disclosure-dedication doctrine)