Ever since the Supreme Court’s decision in Alice Corp. v. CLS Bank, 134 S.Ct. 2347 (2014), courts have churned out countless decisions holding patents invalid under 35 U.S.C. § 101 for claiming unpatentable subject matter. Most of these patents have involved the application of well-known business methods by means of a computer. In those cases, as in Alice itself, the courts have held that the business methods were unpatentable, abstract ideas, and that the use of a computer to perform the methods did not demonstrate the existence of an “inventive step,” beyond the abstract idea, necessary to establish patentability.
Although most commonly litigated in business method cases, Section 101 is also important in pharmaceutical patent cases, especially those involving patents directed to dosing strategies of known drugs. Significantly, the original formulation of the Alice rule was first expressed by the Supreme Court in Mayo Collaborative Services v. Prometheus Labs, Inc., 132 S.Ct. 1289 (2012). The patent in Mayo involved a method of optimizing doses by evaluating the levels of certain metabolites in the bloodstream of patients. According to the court, it was known in the prior art that the levels of these metabolites were correlated with the likelihood that a particular dose would be safe or effective; and further, the methods for determining these metabolite levels were also old. In holding that the patent was invalid under section 101, the court followed the now well-known two step analysis. First, the court found that the patent was directed to a natural law; namely, the naturally occurring relationship between certain metabolite levels and the likelihood that a dose would be effective and safe. Second, the court examined the claims element-by-element and found that they lacked an inventive concept “sufficient to ensure that the patent in practice amounts to significantly more than a patent upon the natural law itself.” Thus, the patent merely instructed doctors “to engage in well understood, routine, conventional activity previously engaged in by scientists who work in the field.”
The Court in Mayo distinguished between inventions that utilize laws of nature, which are patentable, and mere discoveries of laws of nature, which, though often labor intensive, are not patentable inventions. This analysis applies to many other pharmaceutical patents as well. Recently, Judge Andrews in Delaware adopted a Magistrate Judge’s recommendation that an infringement complaint be dismissed because a patent claiming a method of treating renally impaired patients with reduced doses of oxymorphone (US Patent 8,808,737) was directed to unpatentable subject matter. Endo Pharmaceuticals, Inc. v. Actavis, Inc., Case No. 14-1381, 2015 U.S. Dist. LEXIS 1155034 (D. Del. Nov. 17, 2015) (R&R), 2015 US Dist. LEXIS 127104 (D. Del. Sept. 23, 2015) (adopting R&R). Applying Mayo, the Magistrate Judge had concluded that the patent claims were directed to the natural law observation that bioavailability of oxymorphone is increased in patients with renal impairment. The method steps in the claims merely instructed physicians to measure creatinine levels in the blood to determine renal impairment using a previously recognized method. Judge Andrews found that the patent claimed a “widely-used, well-known method of treating pain” and that “[t]he only new aspect of the ‘737 patent was to tell doctors to adjust the dosage of oxymorphone based upon their discovery of a natural law—namely, how the bodies of individuals with renal deficiencies process the drug.” The patent was invalid under section 101 because it “merely tells doctors to apply the natural law.”
Decisions such as Endo are still limited, but its underlying facts are not uncommon. There are many pharmaceutical patents that purport to cover a new dosage scheme for an old use of an existing drug, where the dose is tailored to the vulnerabilities of a specific subpopulation of patients. To fully exploit their available defenses, ANDA filers should aggressively evaluate Orange Book patents under Mayo as part of their pre-suit validity analysis to determine whether a valid Section 101 defense exists. In many cases, this may be the strongest available defense.