75 F. Supp. 3d 641
D. Del.2014Background
- Cubist sued Hospira for alleged infringement of five patents related to daptomycin (the '967, '689, RE'071, '238, and '342 patents) after Hospira filed ANDA/NDA submissions seeking approval to market daptomycin products.
- The court held a five-day bench trial; Hospira had stipulated to infringement under the court’s existing claim constructions but reserved noninfringement arguments if constructions changed or the RE'071 Certificate of Correction were invalidated.
- The RE'071 patent is a reissue of an earlier patent and a Certificate of Correction changed one amino-acid stereochemistry (L-Asn to D-Asn) in Formula 3; Hospira challenged the Certificate’s validity under 35 U.S.C. §255.
- The asserted claims include dosing method claims (4 mg/kg and 6 mg/kg once every 24 hours and variants), product-by-process purity/composition claims (>=93% or ~97% purity, specific impurity limits), and composition claims requiring combinations of specific Formula 1/2/3 compounds.
- The court found (1) Hospira’s products infringe under the court’s constructions and (2) various validity outcomes: some claims invalidated (anticipation or obviousness) while others (including RE'071 challenges) survived.
Issues
| Issue | Plaintiff's Argument (Cubist) | Defendant's Argument (Hospira) | Held |
|---|---|---|---|
| Validity of Certificate of Correction to RE'071 | Correction merely fixed a minor error; specification shows Formula 3 covered D-Asn so correction is proper | Correction broadened claims by changing stereochemistry and thus is invalid under §255 | Certificate of Correction valid; correction was minor and specification supports D-Asn; Hospira infringes RE'071 |
| RE'071 written description | Specification shows inventors possessed the D-Asn (natural fermentation product) | Original claim language (L-Asn) means specification did not show possession of D-Asn | Written description requirement satisfied; RE'071 not invalid for lack of written description |
| Improper recapture (RE'071 reissue) | Reissue claims do not recapture surrendered subject matter | Hospira: reissue recaptures previously surrendered subject matter (cancelled claim to "substantially pure" daptomycin) | No improper recapture; asserted reissue claims are narrower than the cancelled original claim |
| Claim construction revision for "daptomycin" | Court should construe by stereochemistry (Hospira: original order misapplied technology evidence) | Cubist: intrinsic record defines daptomycin as natural fermentation product; stereochemistry not claimed | Court declines to revise construction; existing construction stands and Hospira’s products infringe under that construction |
| Anticipation of '967 dosing claims (4 mg/kg & 6 mg/kg q24h) | Woodworth and '226 patents do not enable or inherently disclose minimizing skeletal muscle toxicity | Hospira: Woodworth expressly recommends 4–6 mg/kg/day; '226 discloses dose ranges covering claimed doses; inherent disclosure of toxicity minimization | '967 claims anticipated by Woodworth (enabled and inherent disclosure); '226 not enabling for specific claimed doses (broad range) |
| Obviousness of '967 and '689 dosing claims | Dosing regimen nonobvious given clinical uncertainties and secondary considerations (commercial success, unmet need) | Prior art + known properties of daptomycin (concentration-dependent killing, long half-life, post-antibiotic effect, reversible toxicity) make once-daily (and adjusted renal dosing) obvious | Court finds claims of '967 and '689 invalid as obvious; secondary considerations insufficient to overcome prima facie case |
| Anticipation of '238 claim 98 (purity/product-by-process) | Claim 98 yields a distinct product (removal of endotoxins and saponins) not present in prior art | Hospira: prior '843 patent produced similar purity; process differences do not create structural/functional distinction | Claim 98 anticipated by '843; process limitations did not impart patentably distinct structural/functional differences |
| Obviousness of purity patents ('238, '342) | Micelle formation and downstream purification were unpredictable; patent enabled commercialization and high yields (secondary considerations) | Prior art taught daptomycin aggregation properties and micelle/filtration techniques; anion-exchange chromatography was routine after saponin removal | Court finds asserted purity claims obvious; secondary considerations (yield, commercialization) lacked sufficient nexus to claims |
| §102(f) derivation defense (inventorship for purity patents) | Hospira: inventors derived claimed methods from others | Cubist: derivation claim was not timely disclosed pretrial; Hospira failed required notice | Derivation defense barred as untimely and precluded under local rules and §282 notice requirements |
Key Cases Cited
- Superior Fireplace Co. v. Majestic Prods. Co., 270 F.3d 1358 (Fed. Cir. 2001) (correction that broadens a claim is not a "mistake of minor character")
- Central Admixture Pharmacy Servs., Inc. v. Advanced Cardiac Solutions, P.C., 482 F.3d 1347 (Fed. Cir. 2007) (assessing whether a certificate of correction broadens claim scope)
- Tillotson, Ltd. v. Walbro Corp., 831 F.2d 1033 (Fed. Cir. 1987) (corrected claim invalid if it covers any conceivable apparatus/process not covered originally)
- Merck & Co. v. Teva Pharm. USA Inc., 347 F.3d 1367 (Fed. Cir. 2003) (claims must be construed consistently with the specification)
- Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005) (claim construction principles and reliance on intrinsic evidence)
- Vas-Cath Inc. v. Mahurkar, 935 F.2d 1555 (Fed. Cir. 1991) (written description/factual inquiry on possession)
- Ariad Pharm., Inc. v. Eli Lilly & Co., 598 F.3d 1336 (Fed. Cir. 2010) (written description standard: specification must convey possession)
- KSR Int’l Co. v. Teleflex, Inc., 550 U.S. 398 (2007) (clarified obviousness standard; flexible, avoids rigid TSM test)
- Amgen Inc. v. F. Hoffmann-La Roche Ltd., 580 F.3d 1340 (Fed. Cir. 2009) (product-by-process claim analysis focuses on the product, not process)
- Sanofi-Synthelabo v. Apotex, Inc., 550 F.3d 1075 (Fed. Cir. 2008) (anticipation requires an enabling prior-art disclosure)