Appeals from the United States District Court for the
District of Delaware in Nos. 1:14-cv-01381-RGA,
1:14-cv-01382-RGA, 1:14-cv-01389-RGA, Judge Richard G.
Jay Black, Dechert LLP, Philadelphia, PA, argued for
plaintiff-appellant. Also represented by Sharon K. Gagliardi;
Blake Greene, Austin, TX; Jonathan Loeb, Mountain View, CA;
Robert Rhoad, Princeton, NJ.
William H. Burgess, Kirkland & Ellis LLP, Washington, DC,
argued for defendants-appellees Actavis LLC, Ac-tavis South
Atlantic LLC, Teva Pharmaceuticals USA, Inc. Also represented
by John C. O'Quinn; James F. Hurst, Chicago, IL; Leslie
M. Schmidt, New York, NY; Howard S. Suh, Charles A. Weiss,
Eric H. Yecies, Holland & Knight, LLP, New York, NY.
Wu, Goodwin Procter LLP, New York, NY, for
defendants-appellees Teva Pharmaceuticals USA, Inc., Barr
Wallach, Clevenger, and Stoll, Circuit Judges.
Pharmaceuticals Inc. appeals the district court's
decision holding the claims of U.S. Patent No. 8, 808, 737
ineligible under 35 U.S.C. § 101. See Endo Pharms.
Inc. v. Actavis Inc., No. 14-cv-1381-RGA, 2015 WL
7253674 (D. Del. Nov. 17, 2015) ("District Court
Op."), adopting report and recommendation,
2015 WL 5580488 (D. Del. Sept. 23, 2015)
("Magistrate Op."). Because the district
court incorrectly concluded that the claims at issue are
directed to a natural law, we reverse.
owns the '737 patent, entitled "Method of treating
pain utilizing controlled release oxymorphone pharmaceutical
compositions and instruction on dosing for renal
impairment." '737 patent Title. As explained in the
specification, the patent covers a method of using
oxymorphone to treat pain in patients with impaired kidney
function. Id. at col. 1 ll. 19-32.
Controlled-release dosage forms that maintain optimal levels
of pain relief for longer periods are useful to patients and
clinicians. Id. at col. 2 ll. 13-16. Patients'
pain relief levels can be impacted by the way their body
processes oxymorphone. For example, patients with impaired
kidney function, also known as renal impairment, can
experience buildup of waste products and some drugs that are
typically filtered out by the kidneys. Id. at col. 2
inventor of the '737 patent studied the effect of renal
impairment on the pharmacokinetics-including metabolism-of
oxymorphone. Id. at col. 27 ll. 60-67. The '737
patent relates to his discovery that patients with renal
impairment in need of pain relief can be treated in a new,
different way than other patients. Specifically, the inventor
discovered that patients with moderately or severely impaired
kidney function need less oxymorphone than usual to achieve a
similar level of pain management. Id. at col. 10 ll.
15-19. Accordingly, the inventor's treatment method
advantageously allows patients with renal impairment to
ingest less oxymorphone while still treating their pain.
Stated somewhat differently, the inventor developed a method
that allowed renally impaired pain patients to be treated
safely and effectively notwithstanding their impaired kidney
technical terms, the inventor found that there was a
statistically significant correlation between plasma
AUCfor oxymorphone and a patient's degree
of renal impairment, as indicated by their creatinine
clearance rate. Id. at col. 46 ll. 38-40. The
subjects were separated into four groups based on their
creatinine clearance rates:
Creatinine Clearance Rate
> 80 mL/min
Mild Renal Impairment
51 to 80 mL/min
Moderate Renal Impairment
30 to 50 mL/min
Severe Renal Impairment
Id. at col. 30 ll. 30-35. These four groups were
studied for their pharmacokinetic responses to oxymorphone as
measured by their AUC levels. There was relatively little
change in oxymorphone AUC until the subjects had
moderate-to-severe renal impairment (creatinine clearance
rates below 50 mL/min). Subjects with severe renal impairment
(creatinine clearance rates below 30 mL/min) had the highest
AUC values. See id. at col. 46 ll. 38-46, col. 30
ll. 30- 35.
Id. at Fig. 16 (excerpted, annotated). "Because
of this, the oxymorphone levels in the blood of a patient
with  renal impairment are higher than the levels that
would be seen in a healthy patient receiving the same
dose." Id. at col. 10 ll. 19-22. For example,
subjects with severe renal impairment had a mean oxymorphone
AUC, on average, 1.7 times greater than healthy subjects.
Id. at col. 46 ll. 25-30.
Plasma Pharmacokinetic Results
Level of renal impairment
Oxymorphone AUC (ng·hr/mL)
Id. at col. 38 Table 33 (excerpted).
with this discovery, the inventor developed a new method of
using oxymorphone to treat patients with renal impairment,
claimed in the '737 patent. As the specification
explains, "the present invention provides methods using
oxymorphone in the treatment of pain," including
"providing a patient [with renal impairment] with a
therapeutically effective amount of oxymorphone."
Id. at col. 3 ll. 33-36. The specification further
explains that the method "avoid[s] possible issues in
dosing" and allows for treatment with "the lowest
available dose" for ...