Introduction
On April 13, 2018, the U.S. Court of Appeals for the Federal Circuit in Vanda Pharmaceuticals affirmed a district court decision regarding patent eligibility under 35 U.S.C. § 101 of a method of treatment. [1] In Vanda, the Federal Circuit applied the eligibility test set forth by the U.S. Supreme Court in Mayo v. Prometheus, [2] and the majority held that the claimed therapeutic method was patent eligible subject matter. [3] This holding of eligibility by the majority, along with the reasoning behind the holding, provides noteworthy insights relevant to patent prosecution and patent litigation, particularly in view of the previous absence of Federal Circuit decisions directly related to eligibility of therapeutic methods.
The Patent at Issue
As noted by the Federal Circuit, the patent at issue [4] “relates to a method of treating schizophrenia patients with iloperidone wherein the dosage range is based on the patient’s genotype.” The patent eligibility of the claimed therapeutic method was challenged on the alleged basis that the claims were directed to a natural law or phenomenon and thus indistinguishable from the invalid claims in Myriad [5] and Mayo. [6] The Federal Circuit characterized the first independent claim as a representative claim, and this claim recites the following:
A method for treating a patient with iloperidone, wherein the patient is suffering from schizophrenia, the method comprising the steps of:
determining whether the patient is a CYP2D6 poor metabolizer by: obtaining or having obtained a biological sample from the patient; and performing or having performed a genotyping assay on the biological sample to determine if the patient has a CYP2D6 poor metabolizer genotype; and
if the patient has a CYP2D6 poor metabolizer genotype, then internally administering iloperidone to the patient in an amount of 12 mg/day or less, and if the patient does not have a CYP2D6 poor metabolizer genotype, then internally administering iloperidone to the patient in an amount that is greater than 12 mg/day, up to 24 mg/day, wherein a risk of QTc prolongation for a patient having a CYP2D6 poor metabolizer genotype is lower following the internal administration of 12 mg/day or less than it would be if the iloperidone were administered in an amount of greater than 12 mg/day, up to 24 mg/day.
The Majority Opinion
The patent eligibility of the claimed therapeutic method was specifically challenged on the alleged basis that the claimed method is directed to a natural relationship between iloperidone, CYP2D6 metabolism, and QT prolongation and “adds nothing inventive” to those natural laws and phenomena. However, the majority of the Federal Circuit disagreed, in particular asserting that the inventors indeed recognized these natural relationships but nevertheless claimed a patent eligible application of the relationships.
In making this determination, the Federal Circuit applied the two-step eligibility test set forth by the U.S. Supreme Court in Mayo: The first step requires determining whether the claims are “directed” to a patent-ineligible concept. The second step is undertaken only if the first step is not fulfilled, and requires determination of whether the claim includes an inventive concept, i.e., an element or combination of elements that ensures that the patent would be significantly more than a patent merely upon the ineligible concept itself.
The majority here in Vanda noted that the claims require a treating doctor to administer iloperidone in one of two doses, depending on the result of a genotyping assay. The specificity of the claim language was also emphasized by the majority: “the claims...
