IP Law Daily Gas distribution company did not infringe nitric oxide treatment patents
Tuesday, August 27, 2019

Gas distribution company did not infringe nitric oxide treatment patents

By Thomas Long, J.D.

Patent claims related to methods of administering inhaled nitric oxide were patent-ineligible as directed to a natural phenomenon, and other claims for devices and methods for administering gas were not infringed by an accused product.

Claims of five patents related to methods of administering inhaled nitric oxide to neonates with hypoxic respiratory failure—which instructed doctors not to administer the drug to patients having a congenital heart condition, due to the risk of those patients contracting pulmonary edema—were directed to a natural phenomenon and were ineligible for patent protection under 35 U.S.C. §101, the U.S. Court of Appeals for the Federal Circuit has held. In addition, the district court correctly construed a key claim term in five other patents related to devices and methods for administering gas, in finding that a competitor’s product did not infringe those patents. The Federal Circuit affirmed a decision of the federal district court in Wilmington, Delaware, that a distributor of gases to the medical profession that produced a nitric oxide cylinder and nitric oxide delivery service was not liable for infringing the asserted patents (INO Therapeutics LLC v. Praxair Distribution Inc., August 27, 2019, Prost, S.).

At issue were five patents held by INO Therapeutics LLC, Mallinckrodt Hospital Products Inc., and Mallinckrodt Hospital Products IP Ltd. (collectively, "Mallinckrodt") related to methods of administering inhaled nitric oxide (iNO) gas, including U.S. Patent Nos. 8,282,966 ("the ’966 patent"), 8,293,284 ("the ’284 patent"), 8,795,741 ("the ’741 patent"), 8,431,163 ("the ’163 patent"), and 8,846,112 ("the ’112 patent") (collectively, "heart failure patents" or "HF patents"), and five patents related to devices and methods for administering gas, including U.S. Patent Nos. 8,573,209 ("the ’209 patent"), 8,776,794 ("the ’794 patent"), 8,776,795 ("the ’795 patent"), 9,265,911 ("the ’911 patent"), and 9,295,802 ("the ’802 patent") (collectively, "delivery system infrared patents" or "DSIR patents").

Mallinckrodt sued Praxair Distribution Inc. and Praxair Inc. (collectively, "Praxair"), alleging that Praxair’s nitric oxide gas product, Noxivent, infringed Mallinckrodt’s HF patents and device claims of the DSIR patents when used with Mallinckrodt’s DSIR system. Mallinckrodt also alleged that Praxair’s proposed gas delivery device (named "NOxBOXi") infringed a method claim of the DSIR patents. After a bench trial, the district court issued a memorandum and order concluding that the HF patents were ineligible under Section 101 and the DSIR patents were not infringed. Mallinckrodt appealed.

Subject-matter eligibility—HF patents. Mallinckrodt contended that the district court erred by concluding that the asserted claims of the HF patents are ineligible under Section 101. The Federal Circuit agreed with the district court that claim 1 of the ’741 patent was ineligible because it was directed to a natural phenomenon and contained no inventive steps rendering it patentable.

"It is undisputed that treatment of infants experiencing hypoxic respiratory failure with iNO gas has existed for decades," said the court. The patent claim did no more than add an instruction to withhold iNO treatment from certain patients in whom the inventors had noticed an adverse reaction (pulmonary edema). It did not recite giving an affirmative treatment for the iNO-excluded group, and therefore it covered a method in which, for the iNO-excluded patients, the body’s natural processes were simply allowed to take place. Consequently, the claim was directed to the natural phenomenon.

The invention was not focused on changing the physiological state of the patient to treat the disease. Rather, the claimed invention was focused on instructing doctors to screen for patients who had a condition making them subject to pulmonary edema if treated with iNO gas—specifically, a congenital heart condition called LVD. This amounted to claiming a natural law, in the appellate court’s view. Apart from the natural phenomenon itself, the claim involved only well-understood, routine, and conventional steps. "Claim 1 does not recite a set of dosages that offer some relief to LVD infants while minimizing the risk of an adverse event," the court explained. "It simply sets out an observation of the adverse event, and then instructs the physician to withhold iNO treatment." Mallinckrodt did not develop a new way of using an existing drug; the claimed method recited an old use of an old drug, and merely proposed not using the drug in certain patients.

Therefore, the Federal Circuit affirmed the district court’s decision that claim 1 of the ’741 patent is ineligible under Section 101, as well as asserted claims 4, 7, 9, and 18 of the ’741 patent; claim 20 of the ’966 patent; claim 18 of the ’284 patent; claims 9, 11, 13, and 15 of the ’163 patent; and claims 1, 7, and 9 of the ’112 patent.

Noninfringement—DSIR patents. Mallinckrodt argued that the district court erroneously construed the term "verify" when analyzing whether Praxair’s proposed gas cylinder infringed the DSIR patents. Claim 1 of the ’794 patent required the device "verify one or more of the gas identification, the gas concentration and that the gas is not expired." The district court never formally construed "verify," but applied its plain and ordinary meaning. The district court determined that the system did not "verify" the gas data when one simply took a meter from Mallinckrodt’s gas cylinder (containing data about the gas from the manufacturer) and used it with a Praxair gas cylinder (which does not contain a meter with gas data). In the district court’s view, the claim term required that the gas delivery system verify data about the actual gas in the "gas source" (that is, the cylinder being used). The appellate court agreed with the district court’s interpretation and rejected Mallinckrodt’s contention that the DSIR patent claims are practiced when any iNO cylinder is combined with a circuit storing gas data—even if the data is unrelated to the particular gas in the cylinder. Mallinckrodt did not dispute that under the district court’s interpretation of the plain meaning of the claims, Praxair’s cylinder did not infringe.

In addition, the Federal Circuit agreed with the district court’s conclusion that because Praxair’s delivery system (NOxBOXi) did not "verify" the gas either, it did not infringe claim 15 of the ’794 patent, which was representative of the DSIR patents’ method claims. Mallinckrodt’s expert had testified that the NOxBOXi’s gas data did not come from the gas source.

The Federal Circuit affirmed the district court’s determination of noninfringement for asserted claims 1 and 15 of the ’794 patent, claim 6 of the ’209 patent, claims 1 and 15 of the ’795 patent, claims 1 and 10 of the ’911 patent, and claims 1 and 10 of the ’802 patent.

Technical error. Finally, Mallinckrodt challenged a technical error in the district court’s final judgment order. The district court did not limit its ruling to the asserted claims before it, but instead erroneously made a blanket ruling that each Mallinckrodt patent in its entirety was invalid or not infringed. The Federal Circuit remanded to allow the district court to correct this clerical error.

Concurring and dissenting opinion. Circuit Judge Pauline Newman wrote separately, concurring-in-part and dissenting-in-part. Judge Newman concurred in the correction of the district court’s technical error. However, she dissented from the majority’s determination that the claims at issue were ineligible for patenting under Section 101. In Judge Newman’s view, the claims were for a method of medical treatment, a class of subject matter the Section 101 eligibility of which had been established by precedent. "The method that is described and claimed does not exist in nature; it was designed by and is administered by humans," Judge Newman opined.

This case is No. 18-1019.

Attorneys: Seth P. Waxman (Wilmer Cutler Pickering Hale and Dorr LLP) for INO Therapeutics LLC. William R. Peterson (Morgan, Lewis & Bockius LLP) for Praxair Distribution Inc.

Companies: INO Therapeutics LLC; Praxair Distribution Inc.

MainStory: TopStory Patent FedCirNews

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