In a remand case from the U.S. Supreme Court to the U. S. Court of Appeals for the Federal Circuit, the Federal Circuit has now issued a post-Bilski decision finding that the claimed method of treatment claims are directed to patentable subject matter under 35 U.S.C. §101 because the recited steps satisfy the “machine-or-transformation test.” Prometheus Laboratories v. Mayo Collaborative Services, Case No. 08-1403 (Fed. Cir., Dec. 17, 2010) (Lourie, J.).

This case had been remanded to the Federal Circuit from the Supreme Court (directly from a grant of cert.) for further consideration following the Supreme Court’s decision in In re Bilski. (SeeIP Update, Vol. 13, No. 1.) In its first consideration of this case, the Federal Circuit held that the district court erred as matter of law in finding that Prometheus’ asserted medical treatment claims were drawn to non-statutory subject matter. In that decision (see IP Update, Vol. 13, No. 8), the Court concluded that Prometheus’ claims were drawn to statutory subject matter under the “machine-or-transformation test,” which, at the time, was the definitive test for determining patentability of a process under 35 U.S.C. §101. Of course, following its review of the Federal Circuit’s decision in Bilski, the Supreme Court held that the “machine-or-transformation” test is not the sole test for determining the patentability of a process.

The claims of the patents in issue are directed to methods for determining the optimal dosage of thiopurine drugs—e.g., 6-mercaptopurine (6-MP) and azathiopurine (AZA)—used to treat gastrointestinal and non-gastrointestinal autoimmune diseases. AZA is a pro-drug that upon administration to a patient converts to 6-MP, which is further broken down to metabolites such as 6-methylmercaptopurine (6-MMP) and 6-thioguanine (6-TG). The claimed method includes the steps of “administering” a drug that provides 6-TG to a subject and “determining” the levels of the drug’s metabolites in the subject. The claims also recite that the measured metabolite levels are then compared to pre-determined metabolite levels that are used to indicate a need to adjust the level of drug administered so as to minimize toxicity and maximize efficacy.

In the present remand, Prometheus argued that neither the Supreme Court’s Bilski decision nor the fact of its remand of the instant case compel a different outcome because its claims satisfy the machine-or-transformation test and are not drawn to a mere abstraction. Prometheus argued that its claims involve a particular transformation of a patient’s body and bodily sample and also the uses of machines to determine metabolite concentrations in a bodily sample. Thus (Prometheus argued), both prongs of the machine-or-transformation test are satisfied. Mayo argued that the patents-in-suit claim a natural phenomenon and are invalid because they preempt all practical use of naturally occurring correlations between metabolite levels and drug efficacy. Mayo contended that any machine or transformation present in the claims is merely insignificant post-solution activity. Mayo argued that the steps of “administering” and “determining” are merely data-gathering steps.

As it did in its initial decision, the Federal Circuit concluded that Prometheus’s claims satisfy the machine-or-transformation test, even though that is no longer the only test for determining patentable subject matter. The Federal Circuit explained that claims such as the asserted treatment claims are always transformative when a defined group of drugs is administered to a human to ameliorate effects of an unwanted condition. In the context of the claimed method, the Federal Circuit concluded that a determining step is transformative because it involves a form of manipulation or modification of a bodily sample to extract the metabolites from the sample and a determination of the concentration of the metabolites. The Federal Circuit distinguished Prometheus from its 1989 decision In re Grams, in which the claims at issue were directed to a process that combined data-gathering steps with a fundamental principle, noting that the method at issue in Grams was directed to steps of performing a clinical test followed by using an algorithm to determine the existence of an abnormality and possible causes for it. Thus, the Federal Circuit explained that the steps in Grams were not transformative.

The Federal Circuit also commented on the inclusion of a mental step in a method claim, noting that inclusion of a final “wherein” clause that may be a mental step does not negate the transformative nature of the prior steps when all steps are taken as whole. The Federal Circuit pointed out that none of the Prometheus claims in the patents-in-suit contained only mental steps.