74 F.4th 1360
Fed. Cir.2023Background:
- United Therapeutics owns U.S. Pat. No. 10,716,793 (method claims for inhaled treprostinil: single-event dose 15–90 µg delivered in 1–3 breaths) and U.S. Pat. No. 9,593,066 (product-by-process/composition claims addressing impurities, salt formation, and storage).
- Liquidia submitted a §505(b)(2) NDA for Yutrepia (a dry powder inhaled treprostinil). United Therapeutics sued for patent infringement; the district court stayed FDA approval of Yutrepia through the ’793 patent’s expiration.
- The district court held that claims 1, 4, and 6–8 of the ’793 patent were not invalid and were infringed (direct and induced). It held claims 1–3 of the ’066 patent invalid as anticipated (but would be infringed absent anticipation); claims 6 and 9 of the ’066 patent were anticipated and not infringed; claim 8 of the ’066 patent was not invalid but not infringed.
- Liquidia pursued an IPR against the ’793 patent; the PTAB issued a final written decision finding the ’793 claims unpatentable as obvious and denied rehearing. That PTAB decision is on appeal and not final for collateral-estoppel purposes.
- Parties appealed: Liquidia challenges claim construction, enablement/written description of the ’793 patent, induced infringement, and infringement of the ’066 claims; United Therapeutics cross-appeals the anticipation findings and the non-infringement rulings for claims requiring ambient storage.
Issues:
| Issue | Plaintiff's Argument (United Therapeutics) | Defendant's Argument (Liquidia) | Held |
|---|---|---|---|
| Claim scope: whether “treating pulmonary hypertension” imports safety/efficacy (esp. for Group 2 PH) | The claim language and specification cover all five PH groups; claims do not require additional safety/efficacy limitations | A skilled artisan would read safety/effectiveness (and Group 2 exclusion) into the claim; Group 2 may be harmed | Court affirmed: term covers all five groups; no safety/efficacy requirement imported into the claim construction |
| Enablement and written description for the ’793 patent (full scope including Group 2) | Spec teaches therapeutically effective single-event dosing (improves hemodynamics); skilled artisan can practice claims without undue experimentation | Spec lacks guidance for treating Group 2 PH and therefore is not enabled or described for full claim scope | Affirmed: claims are enabled and supported; therapeutically effective dose defined by hemodynamic improvement suffices |
| Induced infringement of the ’793 patent given a pending PTAB invalidity finding | Label and evidence show Yutrepia will cause administration of a therapeutically effective single-event dose; inducement intent established | PTAB found claims unpatentable; that non-final finding negates requisite intent to induce (Commil) | Affirmed: induced infringement stands; non-final IPR decision does not eliminate intent or liability |
| Validity and infringement of the ’066 patent (anticipation by Moriarty; ambient-temperature storage claims) | The ’066 claims are not anticipated; Moriarty does not disclose the same purification/specific impurities; Liquidia stores salt at ambient temperature during production thus infringing claims 6 and 8 | Moriarty discloses treprostinil with similar impurity levels (anticipation); Liquidia’s manufacturing/NDA commitments show storage at 2–8°C and no ambient storage | Affirmed: district court did not clearly err — claims 1–3, 6, and 9 anticipated by Moriarty; claims 6 and 8 not infringed because Liquidia does not store treprostinil at ambient temperature |
Key Cases Cited
- Commil USA, LLC v. Cisco Systems, Inc., 575 U.S. 632 (2015) (an invalid patent cannot be infringed; relevance of invalidity to inducement)
- Ariad Pharmaceuticals, Inc. v. Eli Lilly & Co., 598 F.3d 1336 (2010) (written description requirement explained)
- Eli Lilly & Co. v. Teva Parenteral Meds., Inc., 845 F.3d 1357 (2017) (bench-trial infringement findings reviewed for clear error)
- Auto. Techs. Int’l, Inc. v. BMW of N. Am., Inc., 501 F.3d 1274 (2007) (enablement is a question of law reviewed de novo)
- Markman v. Westview Instruments, Inc., 52 F.3d 967 (1995) (claim construction reviewed de novo with factual findings for clear error)
- XY, LLC v. Trans Ova Genetics, L.C., 890 F.3d 1282 (2018) (PTAB/IPR decisions lack collateral estoppel effect until final/affirmed)
- Forest Laboratories, Inc. v. Ivax Pharmaceuticals, Inc., 501 F.3d 1263 (2007) (anticipation review standard)
- Nuvo Pharmaceuticals (Ir.) Designated Activity Co. v. Dr. Reddy’s Laboratories Inc., 923 F.3d 1368 (2019) (written description reviewed for clear error)