Giving doctors and medical researchers wider freedom to diagnose how patients react to drugs and other treatment options, without having to consult a patent lawyer, the Supreme Court on Tuesday unanimously struck down a Canadian company’s patents claiming an exclusive right to control the use of a method for determining the right dosage level of a specific class of drugs to give to a patient.   Finally moving to resolve an issue it has studied off and on for most of a decade, the Court sharply restricted the government’s power to issue patents to those who claim a new way to apply the laws of nature — including the physical reactions of the human body to medicines.   The ruling came in the case of Mayo Collaborative Services, et al., v. Prometheus Laboratories, Inc. (10-1150).

In recent years, the U.S. Patent Office has been approving a rising number of applications for patents on medical diagnostic techniques, treating them as valuable new discoveries.   The trend has been troubling to the medical profession, and to a wide array of research institutions, fearing that medical experimentation — and even routine medical practice by regular doctors — might turn out to be an illegal infringement of someone’s patent rights.   Although the Court’s new decision focused very closely upon the two specific patents directly at issue, some of the language in Justice Stephen G. Breyer’s opinion swept more broadly and amounted to a caution to the Patent Office — and to the special appeals court that reviews patents — to be more skeptical about these moves to obtain medical practice monopolies.

On a more practical level, the decision was a boon to doctors who claim that the case involved something that they do routinely, without thinking about whether they are inviting a patent lawsuit: giving patients different levels of a drug, observing the results by blood tests, and then making a medical judgment about whether they had given too much or too little for that patient.

The decision also rebuffed a suggestion by the federal government that the Court allow more such patent claims to be made, and have them judged not by whether they were patentable at all, but whether they can pass the customary test of being novel and going beyond existing knowledge.  That approach, the Court said, would be an invitation to would-be inventors to try to advance claims that simply apply the laws of nature without adding much to them.

Part of the opinion relied upon an old and familiar limitation on patent rights — that no one can get an exclusive right to use a law of nature or a natural phenomenon.   The Court did not bar inventors from themselves applying natural laws in their supposed creations, but it did insist that an invention do more than simply recite such a law and tell users to apply it.   A patent applicant, the opinion stressed, must go beyond the law by finding new ways to apply it that no one else has previously discovered.  These ideas for application of the natural phenomena, the Court said, must be genuine and they must not be so broad that they actually tie up the use of a law of nature in a monopoly.

The patents at issue in the case involved a method of medical diagnosis, marketed by Prometheus Laboratories, Inc., on an exclusive license from the Canadian owner of the patents themselves.  Prometheus sold its diagnostic test kit, “Pro-Predict,” to doctors and hospitals to help them determine the proper dosage level of a line of drugs, called thiopurines, that are used to treat gastrointestinal disorders, such as Crohn’s disease, that result from abnormalities in the body’s immune system — that is, the body’s ability to fight off “outside” agents in the body.  The main version of this class of drugs have been found also to aid in remission of leukemia as well as in treating some forms of colitis.  Further, they have been used to suppress an immune reaction that seeks to reject a transplanted organ.

When the patient is given a dose of a thiopurine, the body’s chemistry physically transforms it into a metabolite.  Prometheus’s kit tells a doctor how to measure the concentration of the resulting metabolites in a given patient’s blood, then making a medical judgment about whether too much, or too little, of the drug was given to that patient.  The famous Mayo Clinic in Rochester, Minn., and affiliated organizations, bought these kits for a time, but then figured out a way to make some refinements in it, and began using their own test.  Prometheus sued for infringing on the two patents, and won in the specialized patent appeals court, the U.S. Court of Appeals for the Federal Circuit.

The Circuit Court was satisfied, as was the Patent Office, that the inventor of this diagnostic method actually went beyond a mere application of the laws of nature about the body’s reactions.  The inventions, that Court concluded, were a method to produce transformations of the thiopurines into metabolites, with a resulting measurement that had clinical significance.

The Supreme Court had Mayo’s appeal before it once before, but in June 2010 sent it back to the Federal Circuit for a new look.  The Federal Circuit found again that the Pro-Predict kit was properly patented, and Mayo then returned to the Supreme Court, with the backing of an array of medical research organizations and business groups urging the Justices to treat the case as far more significant than a dispute about two specific patents.

Justice Breyer’s opinion striking down the two patents made it clear that the Court saw this case as a major threat that patent monopolies might be granted in a way that would “disproportionately tie up the use of the underlying natural laws, inhibiting their use in the making of further discoveries.”   What these patents involved, the opinion said, were steps in a diagnostic process involving “well-understood, routine, conventional activity previously engaged in by researchers in the field.”

The Court suggested that the test kit involved little more than reciting natural laws about the body’s physical chemistry, and then telling doctors or researchers to apply those laws to the chemical transformations they observed in a patient’s reaction to a dosage level.   It said this was akin to Albert Einstein telling the operators of an atomic testing machine about his law of relativity, and then telling them to apply it.

“What else is there in the claims before us?” Breyer wrote. “The process that each [patent] claims tells doctors interest in the subject about the correlations that the researchers discovered.”  It adds some steps to the diagnostic process, but, Breyer said, those are not “sufficient to transform the nature of the claim” beyond a mere recitation of a natural phenomenon.

In the concluding pages of the opinion, Breyer suggested that the Court had sided — in an energetic debate over whether patent monopolies were critical to generate new discoveries in medical diagnosis — with those who contended that such monopolies threaten to “impede the flow of information that might permit, indeed spur, invention.”  Among the negative effects that might flow from this, Breyer wrote, is raising the price of using patented ideas, requiring potential users “to conduct costly and time-consuming searches of existing patents and pending patent applications, and requiring the negotiation of complex licensing agreements.”

If Congress is persuaded that more patent protection is needed for new discoveries in applying the laws of nature to diagnostic techniques, it has the authority to write new laws, the opinion said.




Posted in Mayo v. Prometheus Laboratories, Analysis, Featured, Merits Cases

Recommended Citation: Lyle Denniston, Opinion recap: Freeing doctors to practice, SCOTUSblog (Mar. 20, 2012, 4:38 PM),