In Vanda Pharmaceuticals Inc. v. West-Ward Pharmaceuticals Int’l Ltd., a divided panel of the Federal Circuit upheld Vanda’s personalized method of treatment claims relating to its Fanapt® (iloperidone) product against a patent eligibility challenge. Interestingly, where the district court had found the claims eligible at step two of the Mayo/Alice analytical framework, the Federal Circuit found them eligible at step one. Chief Judge Prost filed a dissenting opinion.

(The Federal Circuit addressed several important issues in its decision. This article focuses on patent eligibility.)

The Patent At Issue

The patent at issue was U.S. Patent  8,586,610, which is owned by Aventisub LLC, exclusively licensed to Vanda, and listed in the Orange Book for Fanapt® (iloperidone). Claim 1 was deemed representative:

1. 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.

As explained in the Federal Circuit decision, the QT interval is a cardiac rhythm parameter reflecting the time between the Q and T waves of the heart rhythm, and QT prolongation can lead to serious cardiac problems. Iloperidone may cause QT prolongation.

Iloperidone is metabolized by the enzyme CYP2D6, but some individuals have a lower activity of that enzyme. According to the ‘610 patent, treatment of such individuals can be effected more safely with lower doses of iloperidone. As noted in the Federal Circuit decision, the ‘610 patent refers to individuals with low CYP2D6 activity as “CYP2D6 poor metabolizers.”

The District Court Decision

On the issue of patent eligibility, the district court concluded under step one of its Mayo/Alice analysis that “the asserted claims depend upon laws of nature,” i.e., “the relationship between iloperidone, CYP2D6 metabolism, and QTc prolongation.” Nevertheless the court upheld the claims under § 101 at step two of its Mayo/Alice analysis because West-Ward had “not proven by clear and convincing evidence that the precise test and the discovered results were routine or conventional.”

The Federal Circuit Decision

The Federal Circuit decision was authored by Judge Lourie and joined by Judge Hughes. Chief Judge Prost dissented.

The Federal Circuit summarized the parties’ patent eligibility arguments as follows:

• West-Ward argues that the asserted claims are ineligible under § 101 because they are directed to a natural relationship between iloperidone, CYP2D6 metabolism, and QT prolongation, and add nothing inventive to those natural laws and phenomena.
• West-Ward contends that the asserted claims are indistinguishable from those held invalid in Myriad and Mayo.
• Vanda argues that the claims are not even directed to a law of nature or natural phenomena (i.e., that the district court erred at step one of its Mayo/Alice analysis).

The Federal Circuit agreed with Vanda:

In this case, the ’610 patent claims are directed to a method of using iloperidone to treat schizophrenia. The inventors recognized the relationships between iloperidone, CYP2D6 metabolism, and QTc prolongation, but that is not what they claimed. They claimed an application of that relationship. Unlike the claim at issue in Mayo, the claims here require a treating doctor to administer iloperidone in the amount of either (1) 12 mg/day or less or (2) between 12 mg/day to 24 mg/day, depending on the result of a genotyping assay. …. Thus, the ’610 patent claims are “a new way of using an existing drug” that is safer for patients because it reduces the risk of QTc prolongation.

The Federal Circuit also cited its CellzDirect decision as supporting its finding:

In that case, we held that “a method of producing a desired preparation of
multi-cryopreserved hepatocytes cells” was patent eligible. …. We explained that
“[t]he end result of the . . . claims is not simply an observation or detection of the ability of hepatocytes to survive multiple freeze-thaw cycles. Rather, the claims [were] directed to a new and useful method of preserving hepatocyte cells.” …. We further emphasized that “the natural ability of the subject matter to undergo the process does not make the claim ‘directed to’ that natural ability.” Otherwise, claims directed to actually “treating cancer with chemotherapy” or “treating headaches with aspirin” would be patent ineligible.

The Federal Circuit concluded:

At bottom, the claims here are directed to a specific method of treatment for specific patients using a specific compound at specific doses to achieve a specific outcome. They are different from Mayo. They recite more than the natural relationship between CYP2D6 metabolizer genotype and the risk of QTc prolongation. Instead, they recite a method of treating patients based on this relationship that makes iloperidone safer by lowering the risk of QTc prolongation. Accordingly, the claims are patent eligible.

Chief Judge Prost’s Dissenting Opinion

Chief Judge Prost dissented on the patent eligibility issue, agreeing with the district court that the claims are directed to a law of nature, and disagreeing that they recite an additional “inventive concept” that could satisfy § 101.

While the claims here do not solely state a law of nature, they do no more than simply direct the relevant audience to apply it.

Chief Juge Prost criticizes the majority for “fail[ing] to reconcile this substantive similarity between our case and Mayo.” As to CellzDirect, she states, “Here, the end result of the claimed process is no more than the conclusion of a natural law.” According to Chief Judge Prost:

[W]e remain beholden to the holding of Mayo, which, in my view, requires us to find the claims directed to a natural law at step one. (And I find no inventive concept in the claims once the natural law at issue is properly understood in view of Mayo.)

Patent Eligibility Of Therapeutic Methods

As the majority notes here, the Supreme Court in Mayo did distinguish the claims at issue as being “[u]nlike, say, a typical patent on a new drug or a new way of using an existing drug,” and in Myriad the Supreme Court  emphasized that “method claims” and “patents on new applications of knowledge about [particular] genes” were “not implicated by [its] decision.” Thus, the majority’s decision that personalized treatment claims are patent-eligible may stand on good footing. Yet, Chief Judge Prost’s dissent shows that it doesn’t take much extrapolation for the rationale of Mayo to reach method of treatment claims.

At bottom, isn’t “the end result” of any method going to be “no more than the conclusion of a natural law”? After all, we can’t change the laws of nature. We only can invent and discover new and useful processes exploiting them. Isn’t that what § 101 promises a patent for?