Excerpts from the March 2012 Supreme Court opinion read:
- "The patents before us concern the use of thiopurine drugs in the treatment of autoimmune diseases, such as Crohn’s disease and ulcerative colitis. When a patient ingests a thiopurine compound, his body metabolizes the drug, causing metabolites to form in his bloodstream. Because the way in which people metabolize thiopurine compounds varies, the same dose of a thiopurine drug affects different people differently, and it has been difficult for doctors to determine whether for a particular patient a given dose is too high, risking harmful side effects, or too low, and so likely ineffective".
- "Prometheus’ patents set 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. Claim 1, for example, states that if the levels of 6–TG in the blood (of a patient who has taken a dose of a thiopurine drug) exceed about 400 pmol per 8x108 red blood cells, then the administered dose is likely to produce toxic side effects. While it takes a human action (the administration of a thiopurine drug) to trigger a manifestation of this relation in a particular person, the relation itself exists in principle apart from any human action. The relation is a consequence of the ways in which thiopurine compounds are metabolized by the body—entirely natural processes. And so a patent that simply describes that relation sets forth a natural law".
- "The question before us is whether the claims do significantly more than simply describe these natural relations. To put the matter more precisely, do 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? We believe that the answer to this question is no."
- "Absent legislative intervention by Congress, future litigation will provide more detailed guidance. The patent practitioner, however, should be careful to draft patent applications that support an array of claims, including claims that include at least an additional step that implements any claimed measured “natural” correlation for a specific or particular purpose or in a non-conventional manner. In addition, since the law is in flux, and applications can take years to prosecute and often are filed in numerous jurisdictions with different standards, applications should include claims that embody a newly discovered correlation."
Guidepost for patent eligibility
Submitted by Karen G. Potter and Stephanie Seidman, McKenna Long ; Aldridge LLP
Published by San Diego Transcript on May 8, 2012.
A patent directed to a medical diagnostic testing procedure in a human being recently has been invalidated by the Supreme Court in its decision in March in Mayo v. Prometheus. This decision affects the status of claims in patents and pending application in the field of diagnostic testing and, particularly, personalized medicine, such as claims to methods of selecting patients for treatment with a specific drug, and methods of monitoring and assessing efficacy of treatment as it progresses. Such methods are grounded in discoveries of parameters that correlate an activity of a drug in a patient with a treatment outcome upon which treatment decisions can be made. It is this type of claim that was at issue in Mayo v. Prometheus. The claims in the patent at issue in Mayo v. Prometheus included steps of: testing patients administered with a thiopurine drug for levels of a metabolic byproduct of the administered drug; and associating the measured levels of the metabolite to a particular treatment decision regarding dosage. The claims, however, did not include implementation of the correlation, so that any medical professional who measures the level of these known metabolites could be alleged to infringe the claim. It was argued, and the Supreme Court found, that the claim recited nothing more than what occurs in the patient, which is a law of nature. The Supreme Court reasoned that the conversion of the administered drug to its metabolites was a natural process, and that the discovery of this process was no different from the discovery of any law of nature, such as Newton’s laws, which are not patentable subject matter. The Supreme Court stated that affirmative steps of “administering” a drug to a patient and “measuring” levels of the metabolites, which are not themselves laws of nature, did not save the patent because these steps were conventional. This decision provides guidance regarding what may not be patentable, and provides limited guidance regarding what is patentable. The U.S. Patent Office, whose rules, while not binding, will be the barrier encountered by patent applicants, has stated that a claim that includes steps that encompass a law of nature should include other elements so that the “claimed process amounts to significantly more than a law of nature, a natural phenomenon, or an abstract idea with conventional steps specified at a high level of generality appended thereto.” Absent legislative intervention by Congress, future litigation will provide more detailed guidance. The patent practitioner, however, should be careful to draft patent applications that support an array of claims, including claims that include at least an additional step that implements any claimed measured “natural” correlation for a specific or particular purpose or in a non-conventional manner. In addition, since the law is in flux, and applications can take years to prosecute and often are filed in numerous jurisdictions with different standards, applications should include claims that embody a newly discovered correlation.