Mallinckrodt Hosp. Prods. IP Ltd. v. Praxair Distrib., Inc.

Asserted claims were not patentable because they claimed natural phenomena without containing any inventive concept sufficient to transform the claimed phenomena of nature into a patent-eligible application.

October 20, 2017

Robins Kaplan GENERICally Speaking: A Hatch-Waxman Litigation Bulletin

Case Name: Mallinckrodt Hosp. Prods. IP Ltd. v. Praxair Distrib., Inc., No. 15-170-GMS, 2017 U.S. Dist. LEXIS 142644 (D. Del. Sept. 5, 2017) (Sleet, J.) 

Drug Product and Patent(s)-in-Suit: INOmax® (nitric oxide); U.S. Patents Nos. 8,282,966, 8,293,284, 8,795,741, 8,431,163, and 8,846,112 (the “HF patents”), 8,573,209, 8,776,794, 8,776,795, 9,265,911, 9,295,802 (the “DSIR patents”), and 9,279,794 (the “Sensor Drift patent”)

Nature of the Case and Issue(s) Presented: INOmax is a vasodilator indicated to improve oxygenation and reduce the need for extracorporeal membrane oxygenation in term and near-term (>34 weeks gestation) neonates with hypoxic respiratory failure associated with clinical or echocardiographic evidence of pulmonary hypertension in conjunction with ventilator support and other appropriate agents. Praxair argued that it did not infringe the asserted claims and that the HF patents were invalid under § 101. The court agreed.

Why Praxair Prevailed: The court’s analysis of the HF patents focused on claim 1 of the ’741, which it considered representative. That claim recites,

[a] method of treating patients who are candidates for inhaled nitric oxide treatment, which method reduces the risk that inhalation of nitric oxide gas will induce an increase in pulmonary capillary wedge pressure (PCWP) leading to pulmonary edema in neonatal patients with hypoxic respiratory failure, the method comprising:

(a) identifying a plurality of term or near-term neonatal patients who . . . are candidates for 20 ppm inhaled nitric oxide treatment;

(b) determining that a first patient of the plurality does not have left ventricular dysfunction;

(c) determining that a second patient of the plurality has left ventricular dysfunction, so is at particular risk of increased PCWP leading to pulmonary edema upon treatment with inhaled nitric oxide;

(d) administering 20 ppm inhaled nitric oxide treatment to the first patient; and

(e) excluding the second patient from treatment with inhaled nitric oxide, based on the . . . particular risk of increased PCWP leading to pulmonary edema upon treatment with inhaled nitric oxide.

The court performed a two-step Mayo analysis. It found that the claim was directed to a law or phenomenon of nature: “a dysfunctional ventricle, in combination with increased blood flow, could cause a backup of venous blood, and, in turn, edema, is a law of nature taught to first year medical students.” The court discounted plaintiff’s argument that the law was more “probabilistic than deterministic,” because that distinction does not change the physiological reasons for the occurrence of pulmonary edema.

Having concluded that the claim is directed to natural phenomena, the court looked to the second step in a Mayo analysis: Do the claims contain an inventive concept sufficient to transform the claimed law or phenomenon of nature into a patent-eligible application? The court answered, “No.” The plaintiff’s main argument for the second Mayo step involved the (e) limitation—excluding patients from treatment if they had a particular risk of pulmonary edema. The inventor stated that he had made an observation that led to the “invention” claimed in the HF patents. The purpose of the invention, he said, “was to notify physicians ‘to look for a specific circumstance which might indicate that [a] child was at a higher risk of a serious adverse event.’”

This observation was insufficient for the court. It cited Myriad Genetics, Inc., 133 S.Ct. at 2117 for the proposition that “[g]roundbreaking, innovative, or even brilliant discovery does not by itself satisfy the § 101 inquiry.” And in any event, the court downplayed the significance of the observation, stating:

Terminating treatment for patients experiencing adverse reactions to it was known in the art. Tacking that step on to a study’s observation of an adverse event associated with a specific defect does not make the claim patent-eligible.

Turning to the DSIR and the Sensor Drift patents, the defendants did not dispute their validity. Praxair established that its gas cylinders were incompatible with Patentee’s gas delivery system, DSIR. Plaintiffs relied on Intel Corp. v. ITC, 946 F.2d 821 (Fed. Cir. 1991) and its progeny, where because the claims were drawn to “programmable selection means,” the accused apparatus need only be capable of being programmed to infringe when sold. The court found non-infringement because Praxair did not provide hardware to make its gas cylinders compatible with the DSIR devices.

Back to Top