After Cleveland Clinic, IP practitioners were left to speculate about the fate of claims directed to methods of medical treatment. These claims seemed next in line for extinction by the Mayo/Alice rule, which I will paraphrase: “If a patent claim is directed to a phenomenon of nature or abstract idea, it is patent-ineligible unless it contains an additional ‘inventive concept’ and does not merely recite routine and conventional pre or post-solution activity.” In other words, what is patent-eligible about the discovery of the natural phenomenon that drug x can treat pathology y if the discovery that biomarker z correlates with a feature of pathology y and thus can be used to diagnose it, cannot provide the needed inventive concept that will pass step 2B of the Mayo/Alice test. See Genetic Tech’s. v. Meriel (2016) and MPEP 2106.
On April 13th a divided panel of the Fed. Cir. (Lurie writing for Lurie and Hughes, Prost dissenting) affirmed a district court ruling that claims to an improved method of treating schizophrenia (“SC”) with iloperidone (“Ilo”)was not an attempt to claim a natural phenomenon, and so passed test 2A of the Mayo/Alice analysis, and did not need to be dissected to see if it contained the dreaded additional inventive concept of test 2B. (Vanda Pharm., Inc. v. West-Ward Pharm. Int’l Ltd, Appeal No. 2106-2707, -08 (Fed. Cir., April 18th 2018)).
I am well aware that many commentators have already weighed in on this decision, but I have avoided reading their sage analyses on the off chance that I can add some novel thoughts on the majority’s reasoning. The illustrative claim is as follows:
A method for treating a patient with Ilo, wherein the patient is suffering from SC, the method comprising the steps of:
determining whether the patient is a CYP2D6 poor metabolizer [of Ilo] by: br>
obtaining or having obtained a sample from the patient; and br>
performing or having performed a genotyping assay on the biological br>
sample to determine if the patient has a CYP2D6 poor metabolizer genotype; and br>
if the patient has a CYP2D6 poor metabolizer genotype, then internally administering Ilo to the patient in an amount of 12 mg/day or less, and br>
if the patient does not have a CYP2D6 poor metabolizer genotype, then internally administering Ilo to the patient in an amount that is greater than 12 mg/day up to 24 mg/day,
wherein the risk of QTc prolongation (a heart arrhythmia) for a patient having a CYP2D6 genotype is lower following the internal administration of 12 mg/day or less than it would be if the Ilo were administered in an amount of greater than 12 mg/day, up to 24 mg/day.
The task before the majority, of course, was to distinguish this claim from the doomed claims in Mayo v. Prometheus, and they got right to it. (Start at page 26 unless you are eager to have a Hatch-Waxman tutorial or hear about how copying a label can support a charge of induced infringement.) The majority started by noting that the Mayo claims were not directed to a novel method of treating a disease but rather were directed to a diagnostic method that was based on the correlation between the 6-TG metabolite of a drug and the likelihood that a dosage of the drug with be ineffective or cause harm. The S. Ct. found that the claim simply describes this relationship which is, per se, a natural law.
The majority gave great weight to the fact that, although the Mayo claim recited the administration of a 6-TP drug in step one, the Mayo claim as a whole was not directed to the application of a drug to treat a particular disease. The majority used the S. Ct.’s language to support the distinction between a method of treatment claim, such as “a typical patent on a new drug or a new way of using an existing drug, the patent claims do not define their reach to particular application of those laws.” Op. at 29. The majority went on to reason that while Vanda recognized “the relationships between Ilo, CT2D6 metabolism, and [the heart condition], that is not what they claimed. They claimed an application of that relationship… 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 [the heart condition].”
Ed.’s note: Regimen claims (my term) like these, Prometheus’ and Mayo’s, which often appear in “add-on” patents as attempts to lengthen the terms of major drugs, have historically been disfavored by the Fed. Cir., but in the past they have been invalidated under 102/103, not under 101. More on this below.
The majority also discussed and dismissed preemption. They and distinguished the S. Ct.’s reasoning that the claims in Mayo would “tie up the doctor’s subsequent treatment decision” again stating: “The Mayo claim was not a treatment claim, It was ‘not limited to instances in which the doctor actually decreases (or increases) the dosage level where the test results suggest that such an adjustment is advisable.” The majority again discussed the importance of the specificity of the dosages recited in the Vanda claims. Myriad was quoted for the Court’s endorsement of patents on new applications of knowledge about particular genes, that were not implicated by its decision that isolated human genes are natural products. The majority 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….[t]hey recite a method of treating patients based on this relationship that makes Ilo safer by lowering the risk of [the heart condition].”
So, can we read this decision as broadly holding that method of treatment claims are patent-eligible. I have characterized Mayo as involving an old use of an old compound but, with US Pat no. 8.586,610 in hand, it is difficult to tease out what was new about the claims in view of what was already known about the CYP2D6 gene and the enzyme it produced that could metabolize Ilo with varying efficacy, depending on mutations that were present. See, Background of the Invention.
So, whether or not the ‘610 claims will eventually withstand obviousness challenges, they are indeed “specific”, and that made all the difference, at least when distinguishing Mayo was the task at hand. But there are other ways to, at least conceptually, distinguish the Mayo claims. Prescreening the patient was not recited in the Mayo claim. The patient was simply administered what the doctor hoped would be an effective dose of the drug and at some later time, the metabolite was measured to see if the dose fell within an optimal range that had been predetermined by the inventors. (This range was in the claim and it was specific). Then, presumably, since this language was not in the claim, the next dose of the drug might be higher, lower or unchanged from the “test dose.”
In the ‘610 claim, the individual patient is pre-screened by genotyping to determine whether the patient’s ability to metabolize Ilo with their endogenous CYP2D6 enzyme is normal or reduced, before any Iio is administered. If it is reduced, the “normal” dosage of the anti-SC drug Ilo is reduced. In other words, an SC patient is genotyped and put in one of two metabolic “baskets” before they receive the drug.
Apart from the fact that the ‘610 patent claims are “method-of-treatment” claims, Vanda was able to convince the majority of the panel that the claim was not a covert attempt to claim a natural law. (Actually, there are two correlations in the ‘610 claims – the correlation between mutations in the CYP2D6 gene and normal or “poor metabolizer” activity of the gene product (an enzyme) and the correlation between normal and poor metabolizer enzymes and the risk of a particular heart condition if the patient is treated with Ilo.)
And is genotyping patients and putting them into a plurality of distinct treatment groups even reasonably characterized as a “natural phenomenon”? Would Prometheus have prevailed in Mayo if the claim had ended with a method of treatment step for some but not all of the patients? And would have helped if, in the preamble, the patient was recited to be experiencing a poor response or toxic side-effects prior treatment with the drug, so that the doctor was required to alter the dosing based on the patient’s condition to bring their 6-TG into the optimal range?
Finally, please note that the claim at issue in Mayo has been officially labelled as a “diagnostic claim.” And such a claim can be distinguished when claiming later diagnostic method, can’t it?