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IP Newsflash October 2009: Medical Method with "Patient Transformation" is Patentable Subject Matter

10.01.2009

In late 2008, the U.S. Court of Appeals for the Federal Circuit (CAFC) found a medical procedure for determining the effect of an immunization schedule was not patentable subject matter. Our IP NewsFlash of January 2009 discussed the case ofClassen Immunotherapies, Inc. v. Biogen IDEC et al., Case No. 2006-1634, -1649 (Fed. Cir. Dec. 19, 2008), which raised serious questions about how to patent processes or methods for diagnosing or treating diseases.

A more recent CAFC decision has shed light on how such processes or methods might be deemed patentable subject matter – provided that there is some action in the process that goes beyond mere diagnosis and results in an arguable “patient transformation,” such as adjusting a medication to achieve a perceivable therapeutic effect.

The case is Prometheus Laboratories, Inc., v. Mayo Collaborative Services, Case No. 2008-1403 (Fed. Cir. September 16, 2009). This case is the first precedential CAFC decision applying the “machine-or-transformation test” set forth in In re Bilski, 545 F.3d 943 (Fed. Cir. 2008), certiorari granted, 556 U.S. 1 (June 1, 2009), to a medical method. (The Classen case was non-precedential, which means that it is not properly citable in other lawsuits as standing for any particular legal proposition.) In the Bilski case, the CAFC held that claims drawn to a “process” must be tied to a particular machine or apparatus, or transform a particular article into a different state or thing, to be eligible for patenting under 35 U.S.C. § 101. This has come to be called the “machine-or-transformation” test.

The patent claims in the Bilski case were directed to a “business method” and were held invalid under the “machine-or-transformation test”. The CAFC held in that case (in an en banc decision) that the claimed business method was drawn to subject matter that was neither tied to a particular machine nor transformed anything to a different state. MMM’s IP NewsFlash of October 2008 explains that case in more detail.

As of this writing, the In re Bilski case is before the U.S. Supreme Court as Kappos v. Bilski. Oral arguments are expected in November 2009, and a decision is not expected until spring 2010.

In the Prometheus v. Mayo case, Prometheus Laboratories appealed a summary judgment of invalidity of its U.S. Patent Nos. 6,355,623 (“the ‘623 Patent”) and 6,680,302 (“the ‘302 Patent”) granted by the U.S. District Court for the Southern District of California on March 28, 2008. The claims at issue in both patents are directed to calibrating the proper dosage of thiopurine drugs, which are used for treating both gastrointestinal and non-gastrointestinal autoimmune diseases. These thiopurine drugs include 6-mercaptopurine (6-MP) and azathiopurine (AZA). 6-MP is metabolized by the body into a number of metabolites, including 6-methyl-mercaptopurine (6-MMP) and 6-thioguanine (6-TG).

Claim 1 of the ‘623 Patent is representative of the independent claims asserted by Prometheus in the case:

  • 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 having said immune-mediated gastrointestinal disorder; and

  • (b) determining the level of 6-thioguanine in said subject having said immune-mediated gastrointestinal disorder,

  • wherein the level of 6-thioguanine less than about 230 pmol per 8 X 108 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 8 X 108 red blood cells indicates a need to decrease the amount of said drug subsequently administered to said subject.

Claim 1 of the ‘302 Patent is substantially the same, with the inclusion of determining 6-MMP levels in addition to 6-TG.

In the lawsuit, Mayo attempted to obtain a quick disposition of the case against it by filing a motion for summary judgment of invalidity, arguing that the patents were invalid because they claim unpatentable subject matter under 35 U.S.C. § 101. On March 28, 2008, the district court granted Mayo’s motion. The court reasoned that the claims have three steps: (1) administer the drug to a subject; (2) determine metabolite levels; and (3) be warned that an adjustment in dosage may be required. The court found that both “administering” and “determining” steps are merely necessary data-gathering steps for use of the correlations. It is notable that the claim does not require administering an increased or decreased amount of drug, which arguably would have resulted in a further transformation of the patient. Rather, the action steps of the claim stop at the “determining” step, which arguably is only a mental step.

In this vein, the court reasoned that the “warning step” is only a mental step, which in itself is not patentable. Secondly, the district court found that those correlations were natural phenomena of natural metabolism and not patentable inventions.

Prometheus appealed the grant of summary judgment of invalidity to the CAFC. On September 16, 2009, the CAFC held that Prometheus’ medical method claims were indeed patent-eligible subject matter under the “machine-or-transformation test” cited in In re Bilski, under 35 U.S.C. § 101. Since no machines are involved in this procedure, the decision necessarily implicated the “transformation” part of the test.

Some in the medical and diagnostic professions would argue that correlations of drug metabolites resulting from a natural body process should not be patent-eligible. This type of reasoning would proscribe patents for a large segment of the biomedical diagnostic methods, and perhaps impact a large segment of the medical diagnostic industry. Typically, these diagnostic methods are centered upon the correlation of a metabolite or a protein/gene marker with a specific disease state or condition. Diagnostic methods using the detection of human marker genes or products are also not “tied to a particular machine or apparatus” nor do they appear to “transform a particular article into a different state.” A rigid application of the “machine-or-transformation” test, under the premise that mere diagnosis, without a particular machine or without some kind of physical transformation, would directly affect the development and incentives for patents claiming diagnostic methods and/or research methods.

The In re Bilski decision suggested, but did not expressly hold, that a transformation of a physical object may not necessarily be required to satisfy the “transformation” part of the test. The CAFC in that case left open the question of whether a data transformation would be deemed sufficient to satisfy the test. The panel in the Prometheus case seemed to pick up on this point and reversed the invalidity holding.

The Prometheus court reasoned that the key issue for patentability is whether a claim is drawn to a fundamental principle(which is not patentable under 35 U.S.C. § 101) or to an application of a fundamental principle (which is patentable under 35 U.S.C. § 101). Furthermore, the involvement of a machine or transformation in the claimed process must not merely be “insignificant extra-solution activity.” In other words, the machine or the transformation must be central to the purpose of the method claims. The court concluded that the methods of treatment claimed in the patents squarely fall within patentable subject matter because there is a transformation in the human body following administration of a drug and the various chemical and physical changes of the drug’s metabolites that enable their concentrations to be determined. The court expressed that the asserted claims are always transformative when a defined group of drugs is administered to the body to ameliorate an undesired condition. Thus, some action that results in a measurable physical change to a patient would seem to satisfy the “transformation” prong of the test and allow a patent to be granted (assuming, of course, that the other conditions for patentability such as novelty and nonobviousness are satisfied).

The court also concluded that determining the levels of 6-TG or 6-MMP involves a transformation. The court explained that it is necessary to extract the metabolites from a bodily sample, which cannot be determined by mere inspection. The court reasoned that the transformation is central to the purpose of the claims, since the determining step, like the administering step, is a significant part of the claimed method of treatment. Lastly, the court determined that the final “wherein” clauses are mental steps and not patent-eligible. However, the mental steps do not negate the transformative nature of prior steps.

The Prometheus decision holds the promise – at least for a short while – that other kinds of “personalized medicine” inventions can be patented. Any kind of treatment that changes the body or its contents in some way should be found to be transformative and thus patent-eligible. However, the Supreme Court could proverbially “kill the patent patient” by rendering a decision that mandates a rigid application of the machine-or-transformation test. This is not expected to occur because of the widespread negative implications for many industries and fields other than medicine. No matter how the Supreme Court rules, there will be significant effects.

Although the Prometheus case tries to answer questions directed to methods of treatment, it does not provide any guidance of how claims drawn to medical diagnostic methods, research tools, or specifically research protocols should be drafted to be deemed patentable subject matter. For now, and the next few months, novel medical treatments that result in perceivable transformations of a patient should continue to be held patentable and upheld in the courts. However, it is clear that a strict bright-line test solely using the “machine-or-transformation test” for patentability under 35 U.S.C. § 101 would dramatically alter the patent landscape. The Supreme Court’s ruling next year in the Kappos v. Bilski case will have a significant impact one way or the other, and those who are invested in the patenting of medical procedures should watch closely for developments in the area.

Eggerton A. Campbell, Ph.D., Patent Agent / Author
(ecampbell@mmmlaw.com) 202.216.4819 (DC office)

John R. Harris, Partner / Editor
(jharris@mmmlaw.com) 404.504.7720 (Atlanta office)

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