Diagnostic methods remain patentable in Australia

In brief 5 min read

In good news for biotech innovators, the Federal Court has confirmed diagnostic methods remain patent-eligible subject matter in Australia. The Federal Court's highly anticipated decision in Sequenom, Inc. v Ariosa Diagnostics, Inc. [2019] FCA 1011 (Sequenom) provides a strong impetus for innovators to continue to develop new diagnostic methods in the important field of biotechnology.

How does this affect you?

The Australian Sequenom decision is welcome news for biotech innovators.

• Diagnostic methods that involve the practical application of a natural phenomenon remain patentable in Australia.

• The decision highlights the different approaches taken by Australian and US courts in relation to the issue of patentable subject matter.

Innovators can take comfort that diagnostic methods remain patentable in Australia.

Background

The patent in question concerns prenatal diagnostic methods for detecting fetal DNA in non-cellular components of a maternal blood sample. The patentee, Sequenom, Inc., commenced infringement proceedings against Ariosa Diagnostics, Inc. and others (collectively, Ariosa), alleging the promotion and supply of Ariosa's 'Harmony' prenatal test in Australia infringed several claims of Sequenom's patent directed to methods for detecting the presence of cell-free fetal DNA (cffDNA) in a maternal serum or plasma sample, and methods of prenatal diagnosis. Ariosa cross-claimed for revocation of the Sequenom patent on various grounds, including that the relevant claims were invalid as they did not define patentable subject matter.

Patentable subject matter

For an invention to be patentable under Australian law, it must meet the statutory patentable subject matter requirement of being a 'manner of manufacture'.

In D'Arcy v Myriad Genetics Inc [2015] HCA 35 (Myriad), the High Court of Australia held that 'isolated' nucleic acids (DNA) per se are not patentable subject matter because the 'substance' of the invention is genetic information, which is not made by human intervention. Relevantly, claims directed to diagnostic methods were not challenged in Myriad (see our discussion of the Myriad decision here). In Myriad, the High Court set out the following principles in relation to 'manner of manufacture' (patentable subject matter):

• the invention must involve an artificially created state of affairs in a field of economic utility (consistent with the High Court's earlier decision in NRDC); and
• the starting point in assessing patentable subject matter is to determine the substance of the claim.

More recently, the Federal Court's decision in Meat & Livestock Australia Limited v Cargill, Inc. [2018] FCA 51 (MLA) was the first to apply the principles set out in Myriad in relation to an invention concerning genetic information. The claims at issue in MLA were directed to methods of identifying particular traits in cattle (such as meat tenderness) by analysing DNA samples. In that case, the Federal Court held that the claims were directed to patentable subject matter because they related to methods of using DNA sequences, rather than the DNA sequences per se (see our discussion of the MLA decision here).

The Sequenom decision

Claim 1 of the Sequenom patent, which is representative of the claims in dispute, is as follows:

A detection method performed on a maternal serum or plasma sample from a pregnant female, which method comprises detecting the presence of a nucleic acid of foetal origin in the sample.

Ariosa sought to rely on statements made by two of the seven judges (Gaegler and Nettle JJ) in Myriad, to support its submission that the 'substance' of the Sequenom claims was the mere discovery (and quantification) of a naturally occurring phenomenon, namely, that cffDNA is detectable in maternal blood products, and that there is no practical application for that discovery provided in the claims. Ariosa further submitted that none of the relevant claims provided an outcome that was an artificially created state of affairs. Rather, even where human action was involved, the end result of each of these claims was mere 'information', eg a diagnosis.

However, Ariosa's submissions were rejected by Beach J, who observed that, in contrast to the situation in Myriad, none of the Sequenom claims were directed to cffDNA per se. Rather, Beach J noted that, as was the case in MLA, the Sequenom claims were directed to methods of identifying or detecting DNA having a particular characteristic, not the DNA per se. The discovery of the existence of cffDNA in maternal blood can, in fact, be put to practical use – as explained in the patent, the invention offered a new non-invasive approach for prenatal diagnosis, including fetal abnormalities, blood typing and sex determination. In particular, Beach J found there was human intervention and an artificially created state of affairs in at least:

1. the taking of a maternal blood from a pregnant female;
2. the separation of the maternal blood into its component parts (plasma, white blood cells and red blood cells);
3. the extraction of DNA from the plasma component of a maternal blood sample; and
4. a step to discriminate between maternal and cffDNA in the sample.

Thus, Beach J concluded that while the substance of the claimed invention was premised on a naturally occurring phenomenon, ie the presence of cffDNA in material blood, it

…builds on, uses, practically applies and reduces to practice a discovered substance found in nature, namely, cffDNA in maternal blood, to provide a new, inventive, useful, artificial method of detection of cffDNA, and where the method is of economic significance.

Accordingly, all relevant claims were found to define patentable subject matter.

This is consistent with the recent decision from the UK courts, which upheld Sequenom's corresponding UK patent. In particular, the UK High Court considered that the relevant claims were directed to 'a practical process of implementing a discovery, for practical applications' and were thus considered to be technical in nature.

In contrast, the situation in the US in regard to diagnostic methods remains problematic. Relevantly, the US Supreme Court recently refused to consider an appeal by Sequenom after equivalent diagnostic claims were found to be invalid by the US Court of Appeal for the Federal Circuit on the basis they 'both begin and end with a natural phenomenon'.

Despite the positive news the Sequenom decision provides to innovators, Beach J's somewhat enigmatic comment at the conclusion of his consideration of 'manner of manufacture' that, initially, he 'tentatively thought that claim 1 and possibly claims 2, 3, and 5, may have been problematic as manners of manufacture. But on further reflection, I am satisfied that they are, although the position [in relation to other claims] is obviously stronger' suggests this decision is unlikely to be the end of the matter, and an appeal seems likely.