Just when it seemed the US Patent Office (USPTO) had relaxed its assessment of patent eligibility for certain types of subject matter relating to nature-based products, the latest chapter of the Myriad saga highlights the challenge of obtaining diagnostic method claims that meet the patent subject matter eligibility threshold in the U.S.

No sooner had the United States Patent & Trademark Office (USPTO) interim guidelines been released (foundhere), they were closely followed by a US Federal Circuit decision issued on 17 December 2014 in University of Utah Research v Ambry Genetics Corporation. which found that certain claims of Myriad’s BRCA gene patents (in US 5,753,441, US 6,951,721 and US 5,654,155) were directed to ineligible subject matter. A copy of the decision can be found here.

The decision is timely because the interim guidelines failed to include (with the exception of the Mayo v Prometheus example) further examples addressing patentability of claims directed to diagnostic methods.  Unfortunately, the decision does not bode well for diagnostics companies and the test used to invalidate the claims at issue is different from the “law of nature” analysis applied in Mayo.

Claims at issue

The Federal Circuit was asked to consider the patent eligibility of two categories of claims.  The first being “primer” claims to the primer sequences per se comprising BRCA1 and BRCA2 primers, and the second being method claims involving a comparison between native BRCA sequence to a patient’s BRCA sequence.

With regard to the method claims at issue, by way of example, one of the representative claims (claim 7 of US 5,753,441) is reproduced below:

 A method for screening germline of a human subject for alteration of a BRCA1 gene which comprises comparing germline sequence of a BRCA1 gene or BRCA1 RNA from a tissue sample from said subject or sequence of BRCA1 cDNA made from mRNA from said sample with germline sequence of wild-type BRCA1 gene, wild-type BRCA1 RNA or wild-type BRCA1 cDNA, wherein a difference in the sequence of the BRCA1 gene, BRCA1 RNA or BRCA1 cDNA of the subject from wild-type indicates an alteration in the BRCA1 gene in said subject, wherein a germline nucleic acid sequence is compared by hybridizing a BRCA1 gene probe which specifically hybridizes to a BRCA1 allele to genomic DNA isolated from said sample and detecting the presence of a hybridization product wherein a presence of said product indicates the presence of said allele in the subject (emphasis added).

The Court concluded that the claims were not directed to “natural phenomena” (as per the reasoning set out in Mayo v Prometheus) but rather were directed to “abstract ideas” akin to the US Supreme Court reasoning in Alice Corp v CLS Bank Int’l (as we previously reported here).  Alice Corp was concerned with a business method for reducing settlement risk by effecting trade through a third-party intermediary.

Analysis of the claims

With regard to the “primer” claims, the Court concluded that although they were synthetically designed, they were not markedly different from naturally occurring DNA because they necessarily contain the identical sequence of the BRCA sequence directly opposite to the strand to which they bind. They are structurally identical to the ends of DNA strands found in nature.  In other words, the Court required the primers to have a different structure from anything found in nature.

For the method claims, a two stage test, first introduced in Mayo v Prometheus and reiterated in Alice Corp (referred to as the “Mayo test”) was used to determine patent eligibility of the claims.

The analysis requires first, a determination as to whether the claims at issue are directed to a “judicially created exception,” e.g., a patent-ineligible concept (as was the case in Alice), and second, whether the remaining elements of the claim either in isolation or combination with other non-patent-ineligible elements, are sufficient to transform the nature of the claim into a patent-eligible application. In other words, is there a further “inventive concept” to take the claim into the realm of patent-eligibility?

Applying this analysis (using the Alice Corp reasoning) to the claim above, the Court decided that the “comparison” step outlined in the first part of the claim of comparing wild-type BRCA1 sequences with the subject’s BRCA1 sequence was an abstract idea.  The second part of the claim which described the way the sequences are compared, namely hybridization and detection, was deemed well-understood, routine and conventional activity which “do nothing more than spell out what practitioners already knew” in terms of how to compare gene sequences.

Within this framework, the U.S. courts appear to now be importing elements of inventive step/obviousness requirements for patentability into subject matter eligibility.  The Australian Courts in contrast, have taken a different approach , relying instead upon the “manner of manufacture” principle set out in the NRDC decision by which to assess patentability.

Additionally, the US Courts are seemingly more inclined to adopt a fragmented analysis of the claims, rather than considering the claims as a whole.

What does this mean for diagnostic method claims?

There are now two separate decisions of the US Courts (the Supreme Court’s Mayo case and the Fed Circuit’s present Myriad case) in which diagnostic method claims have failed to meet the subject matter eligibility requirement under the so called “Mayo Test.”  Notably, under this test, even had the Supreme Court evaluated the present claims at issue following the reasoning set out in Mayo rather than Alice, it is likely that such claims would still have failed for being drawn to a “natural phenomenon,” i.e., merely another one of the judicially recognized exceptions.

However, in common were that the claims at issue were both directed to correlations without going further.  The Federal Circuit hinted that claims which are directed to a specific application of the knowledge of BRCA1 gene mutations are patentable.  For example, if the above-mentioned claim was worded so that it was directed to a method of determining breast and/or ovarian cancer risk in a subject which employed the above comparative analysis for detection of mutated sequences of BRCA1 that correlated with cancer risk, perhaps the claim would have passed the subject matter eligibility threshold with the Court.

This area of law in the U.S. is still in flux.  Therefore, we would caution against viewing this decision as a death knell for diagnostic method claims, and we would encourage our clients, given the complexity of the law in this area to discuss their concerns with their patent attorney.