Endo Pharms. Inc. v. Actavis Inc.

The fact that the “bioavailability of oxymorphone is increased in people with impaired kidney function” is a natural law that is not subject to patent protection.

October 15, 2015

Robins Kaplan GENERICally Speaking: A Hatch-Waxman Litigation Bulletin

Case Name: Endo Pharms. Inc. v. Actavis Inc., Civ. No. 14-1381-RGA, 2015 U.S. Dist. LEXIS 127104 (D. Del. Sept. 23, 2015) (Thynge, M.J.) 

Drug Product and Patent(s)-in-Suit: Opana ER® (oxymorphone); U.S. Patent No 8,808,737 ("the '737 patent") 

Nature of the Case and Issue(s) Presented: Actavis moved to dismiss several counts of plaintiffs’ complaint pursuant to Fed. R. Civ. P. 12(b)(6). Defendants argued that the ’737 patent was facially invalid under 35 U.S.C. § 101 because it was directed to patent-ineligible subject matter. According to the patent’s abstract, the invention "pertains to a method of using oxymorphone in the treatment of pain by providing a patient with an oxymorphone dosage form and informing the patient or prescribing physician that the bioavailability of oxymorphone is increased in patients with renal impairment." The court recommended that Actavis’ motion be granted.

Why Actavis Prevailed: The court first recited Supreme Court precedent in Mayo v. Prometheus, 132 S. Ct. 1289 (2012), which applied a two-part test to evaluate patent eligibility. First, a court must determine if a relevant claim is "directed to one of those patent-ineligible concepts," i.e., a law of nature, natural phenomenon, or an abstract idea. If so, then the court must ask, "what else is there in the claims before us?" The second step established whether an "inventive concept" exists to ensure that the patent in practice amounts to significantly more than a patent on the patent-ineligible concept itself.

Here, Actavis argued that the ’737 patent attempts to cover the natural law that the "bioavailability of oxymorphone is increased in people with impaired kidney function." The claimed method consisted of three steps: (i) a "providing" step; (ii) a "measuring/determining" step; and (iii) an "administering" step. The court found that the providing step is insufficient to make the claim patentable because it simply informs patients and prescribing physicians of the relevant drug to be administered. No inventive concept is recited because the ’737 patent specification admits that extended-release oxymorphone has been available on the market, and that oxymorphone is "widely used in the treatment of acute and chronic pain." The court also found that the measuring/determining step is equally unpatentable. It merely instructs the physician to measure the patient’s creatinine level to determine the level of renal impairment using a previously recognized method. Likewise, the court concluded that the administering step simply limits the relevant audience to patients and prescribing physicians, who treat chronic or acute pain with oxymorphone, and instructs the administration of the correct dosage of oxymorphone depending on the severity of the renal impairment. Lastly, analyzing the claim as a whole, the court found that the steps in combination do not transform the natural law into a patentable application of that law.

Next, the court considered whether the asserted claim potentially preempts a law of nature, which it is required to do when assessing § 101 eligibility. Since all references to "individual numerical values" and "numerical values in the various ranges" are broadened by the terms "about or approximately," it is inevitable that a doctor may infringe by checking a patient’s creatinine level to determine renal impairment (as it is known in the medical field that renal impairment affects the bioavailability of certain drugs) and lowering the dosage of oxymorphone in response to the lab test findings. Thus, throughout the specification of the ’737 patent, there are numerous references, which preempt future inventions and discoveries in this field.

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