Federal Circuit Holds That Claims Directed To Methods Of Treating Pain In A Renally Impaired Patient Are Patent-Eligible Under Section 101

For the second time in as many weeks, the Federal Circuit has reversed a district court's finding of patent ineligibility under Section 101 in the life science space, this time concluding that claims directed to methods of treating pain in renally impaired patients are patent-eligible. In Endo Pharmaceuticals Inc. v. Teva Pharmaceuticals USA, Inc., the Federal Circuit again attempted to narrow the Supreme Court's holding in Mayo and strengthen its own precedent that method of treatment claims are directed to patent-eligible subject matter.1, 2

Endo Pharmaceuticals Inc. (Endo) owns U.S. Patent No. 8,808,737 (the '737 patent), which claims methods of treating pain in a renally impaired patient. The '737 patent purports to disclose the discovery that the bioavailability of controlled-released oxymorphone can be increased in patients with renal impairment, especially in patients with moderately to severely impaired kidney function.3 This increased bioavailability is said to result in a higher level of oxymorphone in the blood of those patients than in the blood of healthy patients receiving the same dose, which can lead to harmful effects if the dose is not decreased.4 Armed with these findings, the inventor is said to have developed a new method of treating pain relief in patients with renal impairment.5

Claim 1 of the '737 patent recites:

A method of treating pain in a renally impaired patient, comprising the steps of:

a. providing a solid oral controlled release dosage form, comprising:

i. about 5 mg to about 80 mg of oxymorphone or a pharmaceutically acceptable salt thereof as the sole active ingredient; and

ii. a controlled release matrix;

b. measuring a creatinine clearance rate of the patient and determining it to be (a) less than about 30 mL/min, (b) about 30 mL/min to about 50 mL/min, (c) about 51 mL/min to about 80 mL/min, or (d) above about 80 mL/min; and

c. orally administering to said patient, in dependence on which creatinine clearance rate is found, a lower dosage of the dosage form to provide pain relief;

wherein after said administration to said patient, the average AUC of oxymorphone over a 12-hour period is less than about 21 ng·hr/mL.

Endo sued the defendants for allegedly infringing claims 1-6 of the '737 patent. Actavis moved to dismiss, arguing that the claims are ineligible under Section 101. The magistrate judge recommended granting Actavis' motion, concluding that under step 1 of the Alice/Mayo test, the claims are...