The U.S. Supreme Court has agreed to review a Federal Circuit Court of Appeals ruling that methods for determining the optimal dosage of thiopurine drugs used to treat gastrointestinal and non-gastrointestinal autoimmune diseases recite patentable subject matter under 35 U.S.C. § 101. Mayo Collaborative Servs. v. Prometheus Labs. Inc., No. 10-1150 (U.S., cert. granted June 20, 2011).

The specific question presented is “[W]hether 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 method at issue involves administering a drug, determining the level of the drug in a patient and deciding whether the amount of the drug should be increased or decreased.

The Federal Circuit decided that the method was patentable after reconsidering the question on remand from the U.S. Supreme Court in light of Bilski v. Kappos, 130 S. Ct. 3218 (2010), which rejected “the machine-or-transformation test as the sole, definitive test for determining patent eligibility of a process under § 101.” Additional details about the Federal Circuit’s ruling appear in Issue 5 of this Bulletin. According to the Mayo Clinic, which sought to invalidate Prometheus Laboratories patents, the case involves “whether a patentee can monopolize basic, natural biological relationships.”