Unanimous Supreme Court Invalidates Prometheus Personalized Medicine Claims

20 March 2012 Publication
Author(s): Courtenay C. Brinckerhoff Kristel Schorr Jeanne M. Gills Stephen B. Maebius

Legal News Alert: Life Sciences

On March 20, 2012, in Mayo Collaborative Services et al. v. Prometheus Laboratories, Inc., No. 10-1150 (S. Ct. 2012), the Supreme Court held that claims directed to methods of optimizing the dose of specific drugs used in the treatment of specific conditions are invalid under 35 U.S.C. § 101 because they impermissibly claim laws of nature. The Court’s decision reversed the Federal Circuit, which had twice upheld the validity of the claims at issue. Specifically, the Court not only found the claimed methods unpatentable, but also viewed as unpatentable the three additional steps recited in the methods because they were insufficient to transform the nature of the claims. While the opinion provides limited guidance on how to distinguish unpatentable claims reciting laws of natures from patent-eligible claims directed to specific applications of laws of nature, it does make clear that patenting personalized medicine methods will require fact-specific, case-by-case strategies. The full Supreme Court decision is available online.


Respondent Prometheus Laboratories, Inc. (Prometheus) is the sole and exclusive licensee of the two patents at issue, which relate to the use of thiopurine drugs to treat autoimmune diseases. The patents set forth processes that identify the correlations between the metabolite levels (produced when the drug is ingested) and the likely harm or ineffectiveness of the drug at certain dosages. Petitioners Mayo Collaborative Services and Mayo Clinic Rochester (Mayo) bought and used diagnostic tests based on Prometheus’ patents. However, upon Mayo’s announcement in 2004 that it intended to sell and market its own diagnostic test, Prometheus sued alleging patent infringement. The District Court agreed that the patents were infringed by Mayo’s tests but granted Mayo summary judgment reasoning that the processes claimed natural laws or natural phenomena and were thus unpatentable. The Federal Circuit reversed, finding the processes to be patent-eligible under the Circuit’s machine-or-transformation test. On remand from this Court in view of Bilski v. Kappos, 561 U. S. ___, the Federal Circuit reaffirmed its earlier conclusion.

The Claims at Issue

The Court focused on claim 1 as being representative of the claims at issue:

1. A method of optimizing therapeutic efficacy for treatment of an immune-mediated gastrointestinal disorder, comprising:

(a) administering a drug providing 6-thioguanine to a subject . . . and
(b) determining a level of 6-thioguanine in the subject . . .
wherein the level of 6-thioguanine less than about 230 pmol per 8x108 red blood cells indicates a need to increase the amount of said drug subsequently administered to said subject and, wherein the level of 6-thioguanine greater than about 400 pmol per 8x108 red blood cells indicates a need to decrease the amount of said drug subsequently administered to said subject.

Thus, the method claim reviewed by the Court recites (1) an “administering” step (i.e., instructing doctor to administer the drug); (2) a “determining” step (i.e., telling the doctor to measure resulting metabolite levels); and (3) a “wherein” step (i.e., describing the metabolite concentrations above which there is a likelihood of harmful side-effects and below which there is a likelihood that the drug dosage is ineffective, thereby informing the doctor of need to alter the drug dosage).

The Federal Circuit Decisions

In its original 2009 decision, the Federal Circuit applied its machine-or-transformation test for patent-eligibility, and held that the method claims satisfied § 101 by meeting the “transformation” prong of the test. According to the Federal Circuit, the “asserted claims are in effect claims to methods of treatment, which are always transformative when a defined group of drugs is administered to the body to ameliorate the effects of an undesired condition.”

Subsequently, the Supreme Court held in Bilski that the machine-or-transformation test is not the only way to evaluate compliance with § 101, although it can be a useful clue or tool for analyzing § 101 compliance. After deciding Bilski, the Supreme Court vacated its original grant of certiorari in Prometheus, and remanded the case to the Federal Circuit.

On remand, the Federal Circuit characterized the issue as “whether Prometheus’s asserted claims are drawn to a natural phenomenon, the patenting of which would entirely preempt its use . . ., or . . . only to a particular application of that phenomenon,” which would be patent-eligible. The Federal Circuit again upheld the claims, finding that they relate to administering specific drugs and measuring specific metabolites, and are therefore “transformative” under the machine-or-transformation test. Indeed, according to the Federal Circuit, the claims do not preempt all uses of natural correlations, but rather utilize them in a series of specific steps relating to particular methods of treatment.

The Supreme Court Decision

Justice Breyer began his unanimous opinion for the Court by citing the language of 35 U.S.C. § 101 noting, “[t]he Court has long held that this provision contains an important implicit exception: ‘[L]aws of nature, natural phenomena, and abstract ideas’ are not patentable.” The Court considered what is required “to transform an unpatentable law of nature into a patent-eligible application of such a law,” and emphasized that the difference depends not merely on words, but on underlying principles. The Court reads earlier Supreme Court precedent, such as Flook and Bilski, as “insist[ing] that a process that focuses upon the use of a natural law [must] also contain other elements or a combination of elements, sometimes referred to as an ‘inventive concept,’ sufficient to ensure that the patent in practice amounts to significantly more than a patent upon the natural law itself.”

Turning to Prometheus’ claims, the Court characterized them as “set[ting] forth laws of nature—namely, relationships between concentrations of certain metabolites in the blood and the likelihood that a dosage of a thiopurine drug will prove ineffective or cause harm.” The Court thus framed the issue before it as whether “the patent claims add enough to their statements of the correlations to allow the processes they describe to qualify as patent-eligible processes that apply natural laws.” In other words, did “the claimed processes . . . have additional features that provide practical assurance that the processes are genuine applications of those laws rather than drafting efforts designed to monopolize the correlations”? The Court decided that they do not.

The Court considered the “administering” step as “simply refer[ring] to the relevant audience,” which was a “preexisting audience,” because doctors already knew to use thiopurine drugs to treat the recited conditions. The Court suggested that even a new “audience” might not have saved the claims, noting that the “prohibition against patenting abstract ideas ‘cannot be circumvented by attempting to limit the use of the formula to a particular technological environment.’”

The Court found the “wherein” clauses do little more than “simply tell a doctor about the relevant natural laws, at most adding a suggestion that he should take those laws into account when treating his patient.”

The Court gave more consideration to the “determining” step, but found it not to bring the claims under § 101 because “methods for determining metabolite levels were well known in the art.” The Court cited the principle that “[p]urely ‘conventional or obvious’ ‘[pre]-solution activity’ is normally not sufficient to transform an unpatentable law of nature into a patent-eligible application of such a law.” Additionally, the Court noted that the “determining” step “could be satisfied without transforming the blood, should science develop a totally different system for determining metabolite levels that did not involve such a transformation.” Accordingly, the “highly general language [in the determining step]” and resulting potential for later discovered processes to “threaten to inhibit the development of more refined treatment recommendations . . .” also influenced the Court’s decision.

Finally, the Court considered the claims as a whole, but found that looking at “the three steps as an ordered combination adds nothing to the laws of nature that is not already present when the steps are considered separately.” That is, “[a]nyone who wants to make use of these laws must first administer a thiopurine drug and measure the resulting metabolite concentrations, and so the combination amounts to nothing significantly more than an instruction to doctors to apply the applicable laws when treating their patients.”

Summarizing the holding, the Court states:

To put the matter more succinctly, the claims inform a relevant audience about certain laws of nature; any additional steps consist of well understood, routine, conventional activity already engaged in by the scientific community; and those steps, when viewed as a whole, add nothing significant beyond the sum of their parts taken separately. For these reasons we believe that the steps are not sufficient to transform unpatentable natural correlations into patentable applications of those regularities.

Upsetting the Status Quo

Many may view the Court’s decision as upsetting the status quo of patent-eligibility that has been followed by the USPTO and upheld by the Federal Circuit. In particular, the opinion provides little guidance on how to apply this holding to other claims. For example, while the Court emphasized that Prometheus’ claims recited only “conventional” steps, it stopped short of indicating that claims with “less conventional” features would have satisfied § 101. On the other hand, the Court was careful to distinguish patents directed to “a new drug or a new way of using an existing drug,” signaling that such claims do not raise issues under § 101.

Accordingly, patent holders in the personalized medicine space should seek the advice of patent counsel to determine whether this decision may be relevant to the validity of their patents. Even if the granted claims look uncomfortably similar to Prometheus’ claims, it may be possible to strengthen or uphold the validity of the patent through the reissue process. A similar approach can be taken in pending applications, such as by amending or adding claims to more directly focus on specific applications of any underlying laws of nature.

Foley attorneys will continue to share updates and insight regarding personalized medicine claims in future client advisories and on our firm’s PharmaPatentsBlog and PersonalizedMedicineBulletin.

The full Supreme Court decision is available online.

Legal News Alert is part of our ongoing commitment to providing up-to-the-minute information about pressing concerns or industry issues affecting our clients and our colleagues. If you have any questions about this update or would like to discuss this topic further, please contact your Foley attorney or the following:

Courtenay C. Brinckerhoff
Washington, D.C.


Kristel Schorr
Washington, D.C.

Jeanne M. Gills
Chicago, Illinois

Stephen B. Maebius
Washington, D.C.

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