Patent Law

Mayo v. Prometheus Labs: Bilski and Medical Methods

By Dennis Crouch

Mayo v. Prometheus Labs (On Remand to the Federal Circuit 2010)

The Federal Circuit's first full post-Bilski decision may come in the case of Mayo v. Prometheus Labs. That case had been pending on a petition for a writ of certiorari to the Supreme Court. In a June 29 order, the Court granted the petition and then summarily vacated the decision with a remand to the Federal Circuit to reconsider the case 'in light of Bilski v. Kappos, 561 U.S. ___ (2010).'  The Supreme Court regularly uses this grant-vacate-remand ('GVR') proceeding for pending cases are impacted by a decision.

In the case, the Mayo Clinic has challenging the validity of two Prometheus patents based upon suspect patentable subject matter. (U.S. Patents 6,355,623 and 6,680,302). 

The Prometheus patents claims an iterative approach to dosing that involves three steps: (1) first administer a drug to a subject; (2) then determine the level of drug in the subject; and (3) finally decide whether the next dose should be the same, higher, or lower. The decision on the next dose is made by comparing the the level of the drug in the subject against predetermined thresholds. Claim 1 of the '302 patent adds additional detail including identifying the active ingredient (6-thioguanine), the diagnosis (a GI disorder), and the predetermined thresholds (e.g., 230 pmol of drug per 8108 red blood cells). Claim 46 of the '623 is a broad claim in that it does not not require the administration step (step 1 from above).

The Federal Circuit held the method patentable under its Bilski test by finding that the required administration of the drug transformed an article into a different state or thing -- essentially creating a per se rule that a method requiring administration of a drug will be deemed patentable subject matter under Section 101. The court also held that the "determining the level" step was necessarily transformative since "those levels cannot be determined by mere inspection." 

On remand, the focus will shift from the machine-or-transformation test to the broader question of whether the claims are directed to a statutory 'process' and/or whether the claim scope is impermissibly abstract. Of course, the machine-or-transformation test may still be instructive in answering these question.

Abstract Idea and Broad Functional Language: The claims are written in broad functional language without tying the the claimed methods to any particular technology. Thus, the "administering" step could potentially be accomplished by any effective method (that has or will be invented) of getting the drug into the subject. Likewise, the patent offers potential methods of "determining the level" of drug in the body (e.g., liquid chromatography) but the claim is broadly written to seemingly cover any mechanism that fulfills that method. 

Novelty Involves the Mental Step: Of course, the general iterative process is well known, what makes the Prometheus claims novel is that they identify the particular thresholds that are important (e.g., 230 pmol). In practice, the process of comparing the thresholds to the subject's drug level is done in the mind of a physician. As Mayo explains, this merely involves the physician's mental recognition of a natural correlation between metabolite levels and patient condition.

The case also represents a growing trend of pitting patient advocates (who want cheaper access to medicine) against innovators (who create better treatments).

Note: In the same Post-Bilski order, the Supreme Court also issued a GVR in the case of Classen Immunotherapies, Inc. v. Biogen IDEC.  On remand, the Federal Circuit will be asked to decide whether the following claim fits within the scope of 35 USC 101:

Claim: A method of determining whether an immunization schedule affects the incidence or severity of a chronic immune-mediated disorder in a treatment group of mammals, relative to a control group of mammals, which comprises immunizing mammals in the treatment group of mammals with one or more doses of one or more immunogens, according to said immunization schedule, and comparing the incidence, prevalence, frequency or severity of said chronic immune-mediated disorder or the level of a marker of such a disorder, in the treatment group, with that in the control group.

Full post as published by Patently Obvious on June 29, 2010 (boomark / email).