by Dennis Crouch
This case focuses on patents covering the opioid drug oxymorphone that Endo sells as Opana ER. In 2017, the FDA requested that (reformulated) Opana ER be removed from the market in response to the high risk of its illicit use. Endo had previously pulled Opana ER from the market in 2012 and then re-launched in a “non-crushable form.” However, that form continued to be abused (including by liquefying and injecting). In response to a new FDA request, Endo again removed the reformulated version from the market. The appeal here is focused on one a subset of the patents covering Opana — a fight between Endo and generic manufacturers who want to start distributing the drug once again.
Endo Pharmaceuticals Inc. v. Teva Pharmaceuticals USA, Inc. (Fed. Cir. 2019)
Endo’s patents at issue on appeal claim a personalized method-of-treatment that has three distinct steps:
- “Providing” the drug (5 to 80 mg of oxymorphone in a controlled release matrix);
- “Measuring” the patient’s creatine clearance rate; and
- “Administering” the drug with dosage calculated based upon the patient’s creatine clearance rate (using a particular formula).
The inventors here were concerned about renal impairment experienced by some folks taking oxymorphone. In their research, they discovered that some folks clear the drug faster (and have fewer kidney problems). The inventors here used the metabolite creatine as an easier to measure proxy for measuring drug clearance (creatine clearance rate) since it comes out in the urine.
These discoveries in hand, the inventors came up with the scheme of giving lower dosages of oxymorphone to individuals with lower clearance rates.
The district court reviewed the claims and found them invalid — holding that the claims were effectively directed to a law of nature. On appeal, the Federal Circuit has reversed and reinstated the patent’s validity. This decision here is the next in a series of decisions creating a hard rule that method-of-treatment claims are patent eligible. See Vanda Pharmaceuticals Inc. v. West-Ward Pharmaceuticals International Ltd., 887 F.3d 1117 (Fed. Cir. 2018) and Natural Alternatives International v. Creative Compounds, LLC, 2019 WL 1216226 (Fed. Cir. Mar. 15, 2019). Here, the court writes:
[T]he asserted claims are not directed to patent-ineligible subject matter. On the contrary, the claims are directed to a patent-eligible method of using oxymorphone … to treat pain in a renally impaired patient. . . .
The claims at issue here are legally indistinguishable from the representative claim in Vanda. Both claims recite a method for treating a patient.
The key precedent here is Mayo v. Prometheus (2012). As in Vanda and Natural Alternatives, the Federal Circuit has characterized Mayo as directed only to a method of optimizing a treatment plan — rather than being a treatment itself. The claims at issue in Mayo require administering a particular drug for treatment of a GI disorder. However, the Federal Circuit explained away that aspect of the claim:
Although the representative claim in Mayo recited administering a thiopurine drug to a patient, the claim as a whole was not directed to the application of a drug to treat a particular disease. Furthermore, the administering step in Mayo is distinguishable from the administering step in the [Endo] patent because the administering step in Mayo is the first step in the method that simply describes giving the drug to a patient with a certain disorder. By contrast, the administering step in the ’737 patent is the step that describes giving a specific dose of the drug based on the results of kidney function testing.
The district court had rejected the clams — agreeing with its magistrat judge that “[t]he administering step merely instructs physicians to dispense oxymorphone for the treatment of pain in a well-know[n] manner, while utilizing the natural law to manage the dosage.”
= = = = =
Question for those of you doing software – What is your equivalent of a “method-of-treatment” claim.