More Diagnostic Method Patent Claims Found Invalid Under Mayo/Alice Framework

Some instability in the interpretation of allowable subject matter in biotechnology patent law continues, as the life science sector contends with recent Supreme Court decisions affecting both composition of matter and method claims. For composition of matter claims, the AMP v. Myriad (2013) Supreme Court case established that an isolated gene was not patentable because it is a product or law of nature, while synthetic non-natural DNA sequences (cDNA) were patentable. The method claims in that case (largely directed to methods to identify mutations in the BRCA1 and BRCA2 genes) were held to be invalid, on the basis that such claims were directed to abstract ideas. Two other cases from the Court established a test for method claims in order to differentiate between impermissible claims to abstract ideas, laws of nature, natural phenomena, and permissible claims to applications or inventive manipulation of such subject matter. The test from Mayo v. Prometheus (2011) (a case with patent claims to method of drug optimization using metabolite testing) was as follows: 

First, we determine whether the claims at issue are directed to a patent-ineligible concept. If the answer is yes, then we next consider the elements of each claim both individually and “as an ordered combination” to determine whether additional elements “transform the nature of the claim” into a patent-eligible application. 

Later, in the software-based Alice v. CLS (2014), the Court reaffirmed this test. In the last several years, lower court cases have contended with applying this test to challenged life science method claims. Most notably, in Ariosa v. Sequenom (Fed. Cir. 2015), using the Mayo test, the Federal Circuit decided that methods for the detection of fetal DNA in maternal serum were invalid as directed to natural laws (see here). That case is likely to be appealed to the Supreme Court.  A recent district court case illustrates the ongoing impact of all of these decisions on patent claims to diagnostic methods iin biotechnology. In Cleveland Clinic v. True Health Diagnostics (N.D. Ohio 2016), the court considered a defendant’s invalidity challenge on its motion to dismiss under Rule 12(b)6. A representative claim from one of the patents in suit is as follows: 

14. A method of assessing a test subject's risk of developing a complication of atherosclerotic cardiovascular disease, comprising: 
determining levels of myeloperoxidase (MPO) activity, myeloperoxidase (MPO) mass,or both in a bodily sample of the test subject, said bodily sample being blood,serum, plasma, blood leukocytes selected from the group consisting of neutrophils and monocytes, or any combination thereof; 
wherein elevated levels of MPO activity or MPO mass or both in the subject's bodily sample as compared to levels of MPO activity, MPO mass or both, respectively,in comparable bodily samples obtained from control subjects diagnosed as not having the disease indicates that the test subject is at risk of developing a complication of atherosclerotic cardiovascular disease. 

Effectively, the method utilizes the observation that levels of the enzyme MPO correlate with blood vessel inflammation, and can thus be indicative of an elevated risk of a cardiovascular event. The patent claim is somewhat similar to the method claim in Mayo, where the observation of a metabolite level was indicative of pharmaceutical effectiveness (or toxicity). On a motion to dismiss by the defendant, the district court applied the Alice/Mayo test and decided that the correlation between MPO and cardiovascular risk was a law of nature, and that the addition of claim steps to “determining” and “comparing” only supplied routine and conventional processes that did not constitute an “inventive concept.” The court noted its standard that it would only “grant the motion only if defendant is able to show invalidity by clear and convincing evidence,” which it found here. The Cleveland Clinic decision (and other similar opinions) reflect the continuing influence of the Mayo/Alice test on life science method claims despite judicial criticism; the field awaits a possible return by the Supreme Court to these issues if Sequenom files a petition for certiorari this year and the Court accepts review.