This is an amplification of my last post on the Sequenom petition for cert. in Sequenom v. Ariosa. I have been arguing for some years that the patent world will never be at rest where diagnostic claims are concerned until the patent eligibility of a simple “If A, then B” claim is addressed by the Fed. Cir. and/or the Supreme Court.

This is the type of claim criticized by Justices Breyer, Souter and Stevens in the “Metabolite Labs dissent” of 2006, when the Court declined to decide the patent-eligibility of a method of detecting a deficiency of cobalamin or folate by assaying a body fluid for an elevated level of homocysteine and correlating the elevated level with a cobalamin or homocysteine deficiency.” Justice Breyer just called the claim a law of nature with a mental step.

Fast forward to 2012 and the Mayo decision (132 S.Ct. 1289), and the Supreme Court invalidated an awkwardly drafted claim that I will re-write here as a method of medical treatment claim:

A method of treating an immunoregulatory disorder by administering a [known drug] so that the metabolite levels of said drug in the blood are between 1 and 10 um/l. (I made up the concentrations, but they represent, on the low side, minimal acceptable efficacy and, on the high side, unacceptable side effects. This is what the Court viewed as a natural phenomenon or correlation).

The Alice decision led the Court to the “Mayo Rule,” that a claim reciting a natural law, phenomenon or abstract idea had to be inspected to see if, in combination with the additional steps, it contained a further inventive concept that would render the claim patent-eligible under s. 101. Little guidance has been provided by the courts or the PTO as to how this rule should be applied in the case of life science claims, particularly to diagnostic claims. (Dicta in Mayo suggested that the Court did not view the claim as directed to a diagnostic method.)

Enter Arisoa. The Fed. Cir. held that the Mayo Rule rendered all the appealed claims patent-ineligible as directed to a natural phenomenon combined with well-known laboratory techniques. And, in fact, most of the appealed claims are broad. Here is claim 1 of US 6,258,540:

1. A method for detecting a paternally inherited[cffDNA] …which method comprises amplifying a paternally inherited nucleic acid of fetal origin from a serum or plasma sample [from a pregnant female] and detecting the presence of cffDNA in the sample.

That’s it. In an earlier post, I noted that only claim 21 recites that a diagnostic test is carried out of the amplified cffDNA. The final step of this claim reads: “providing a [prenatal] diagnosis based on the presence and/or quantity and/or sequence of the foetal nucleic acid.”

The Federal Circuit opinion below noted that this claim was on appeal but did not mention it again in its opinion. But, in Sequenom’s petition it is the only claim that is reproduced in full. Sequenom states that “Claim 21 situates [the steps of amplification and detection of cffDNA] within a larger diagnostic method that up-ended conventional practice.”

Sequenon knew both that a claim to cffDNA in maternal blood was unpatentable as a natural phenomenon. The isolated and purified cffDNA obtained after amplification and detection is a patent-ineligible natural product thanks to Myriad. So Sequenom’s decided that its best approach was to argue that the isolation and detection steps where not conventional because they had never previously been used to isolate and detect the target biomarker, cffDNA. So the Question posed to the Supreme Court might have been: “Is a method directed to isolating a biomarker from a patient sample where it had not been known by the art to occur, patent-eligible under s. 101?” But that is not exactly how Sequenom saw it in its petition, when it wrote that the Question Presented is:

“Whether a novel method is patent-eligible where; (1) a researcher is the first to discover a natural phenomenon; (2) that unique knowledge motivates him to apply a new combination of known techniques to that discovery, and (3) he hereby achieves a previously impossible result without preempting other uses of that discovery.”

The “Question” is more difficult to interpret than many claims, and raises more questions than it answers. Why does the method have to be novel to meet the requirements of s. 101? What is the “natural phenomenon”? But these are minor quibbles that Judge Breyer seems to have answered to his own satisfaction. In other words, any diagnostic test will be based on the discovery of a natural phenomenon. In this case it is not the correlation between cffDNA and any pathological state, it is the existence of cffDNA in maternal blood. Remember, only claim 21 recites carrying out a diagnostic assay based on the cffDNA, but the claim does not recite the condition that is detected.

To continue, the “unique knowledge” [of cff DNA in maternal blood] motivates researcher to apply a new combination of known techniques to that discovery. But the only conceivable difference between the known techniques used to amplify and detect cffDNA and the known techniques to measure elevated homocysteine, does not lie in the analytic techniques but in the marker that is being detected or measured. In other words, the known techniques are in “new combination” because of the marker to which they are applied.

The last factor in the Sequenom Question requires the researcher to achieve a previously impossible result without preempting other uses of the discovery. This can be no more than an tautological attempt to save the claims that do not recite carrying out a diagnostic test. But what is the impossibility that has been overcome? The previously impossible result can only be a blood test that can yield information about the state of the fetus. And all practitioners soon learn the danger of labeling the results of an invention as previously impossible.

But doesn’t any new diagnostic test achieve a result that is “impossible” before it was discovered? To come full circle, it was surely “impossible” to predict the likelihood of a man’s developing prostate cancer before the PSA assay was discovered – e.g., before it was discovered that PSA was a fairly reliable biomarker for imminent or present prostate cancer. (And there were other uses for the homocysteine assay as well – at least in 2006, lack of preemption would not have saved that claim from Justice Breyer.)

Until the recognition of the significance of a natural correlation by a researcher is given weight as an “unconventional step” per se, the relentless degradation of patent claims for both diagnostic methods and methods of medical treatment [remember my Mayo claim, above] will continue. That’s why Judges Lourie and Moore are my current superheroes, since, in their Ariosa concurrence, they wrote that “the patent’s claims merely ‘rely on or operate by, but do not recite [claim?] a natural phenomenon…and that barring such inventions under s. 101 would mean that ‘nothing in the physical universe would be patent eligible.'” Sequenom wants the Supreme Court to reverse on the basis that the Fed. Cir. is applying the Mayo Rule too broadly. I don’t think they are wrong. I just don’t like the condition of the horse they rode in on.