Mayo Collaborative Services v. Prometheus Laboratories, Inc. (Supreme Court 2011)
by Dennis Crouch
The Supreme Court has agreed to hear Mayo's petition on the patentable subject matter eligibility of medical diagnostic methods. The issue raised on appeal is stated as follows:
Whether 35 U.S.C. § 101 is satisfied by a patent claim that covers observed correlations between blood test results and patient health, so that the claim effectively preempts all uses of the naturally occurring correlations, simply because well-known methods used to administer prescription drugs and test blood may involve “transformations” of body chemistry.
The claims asserted by Prometheus are directed toward a method of “optimizing therapeutic efficacy” by first administering an active drug (6-thioguanine) to a subject and then using the subject's metabolite blood-level to adjust future doses of the drug. (U.S. Patents 6,355,623 and 6,680,302). Thus, most of the claims are centered around three ordered-steps of:
administering the drug to the subject;
determining the amount of drug in the subject’s blood; and
re-calibrating the drug dosage based on step-2.
A broader claim (claim 46 of the ‘632 patent) eliminates the administering step of claim 1 above.
The district court found the claims invalid as lacking patentable subject matter under 35 U.S.C. 101. On appeal, the Federal Circuit reversed — holding that the steps of “administering a drug” and “determining the level of 6-thioguanine” were both sufficiently transformative of “a particular article into a different state or thing.” That Federal Circut decision was based on the court's machine-or-transformation test that was subsequently discredited by the Supreme Court in Bilski v. Kappos (2010). In the wake of its Bilski decision, the Supreme Court vacated the Federal Circuit's Prometheus decision and remanded for a new opinion. On remand, the Federal Circuit again affirmed that the Prometheus claims are eligilble for patent protection. [See Rantanan's post]