Patenting biotech in Australia — an update

Obtaining a patent for a biotech invention is crucial to its further development and eventual commercialisation.

Whether it’s a new drug, insecticide or diagnostic, the developer needs to know they will have exclusive ownership of the invention and enjoy a return on their usually significant investment when they take the invention to the market.

So what does Australian law say about what can and can’t be patented in the biotech space?

The law

There are two leading Australian court decisions relating to biotech patentable subject matter.

The first (relevant to all technology areas including biotech) is the often-cited decision in National Research Development Corporation v Commissioner of Patents (1959) 102 CLR 252 (NRDC), which related to a method of removing weeds from a crop using a selective herbicide.

In this case, the High Court ruled that to meet Australia’s non-prescriptive requirements for patentable subject matter (“manner of manufacture”), an invention must relate to an artificially created state of affairs that is of economic significance.

The second is D’Arcy v Myriad Genetics Inc (2015) HCA 35 in which the High Court revoked Myriad’s patent claims for nucleic acids that were markers for breast cancer on the basis that the nucleic acids were mere information.

Nucleic acids

As a result of the Myriad decision, naturally occurring nucleic acids and nucleic acids substantially the same as naturally occurring nucleic acids are no longer patentable.

The reasoning behind this is that although drafted as a product claim, the “substance” of the claim is in fact information that is not “made” by human action. In turn, it is well established that information is not patentable subject matter.

As a result, there is some uncertainty as to the patentability of biotechnology-related inventions.

The Australian Patent Office has produced examination guidelines based on its interpretation of Myriad, which sees the Patent Office applying the exclusion broadly and objecting to claims defining genomic DNA, mRNA, cDNA, interfering RNAs, probes and primers, for example.

However, functional nucleic acids, such as interfering RNAs and exon-skipping nucleic acids, do not encode proteins. Therefore, it is difficult to accept that interfering RNAs and exon-skipping nucleic acids are mere information and encompassed by the exclusion set down in Myriad. In fact, Myriad is completely silent with respect to functional nucleic acids.

To date, the only concession the Patent Office has made is in respect of a composition comprising an interfering RNA, rather than interfering RNA per se (Arrowhead Research Corporation [2016] APO 70), but this has not affected primary examination. Therefore, although it is arguable whether the Patent Office’s interpretation and application of Myriad should be so broad, it seems it will take a hearing before the Patent Office challenging patent office practice and a subsequent appeal to the court to decide whether functional nucleic acids per se are returned to patentability.

Despite current Patent Office practice, non-naturally occurring nucleic acids remain patentable. Examples include single nucleic acids derived from two or more different sources (ie, chimeric nucleic acids) and nucleic acids that encode non-naturally occurring proteins, for example, a humanised antibody such as HERCEPTIN (for treating HER2 positive breast cancer) or a human antibody produced by phage display technology such as HUMIRA (for treating rheumatoid arthritis).

Stem cells

Australian patent law excludes from patentability “human beings, and the biological processes for their generation”. 

This has been interpreted as prohibiting “all biological processes applied from fertilisation to birth — so long as the process is indeed one that directly relates to the generation of the human being”.

The patent examiners’ manual continues to assert that embryos and processes for generating or culturing human embryos for any purpose, including the harvest of stem cells, are not patentable, and that the exclusion extends to all means of generating human embryos and includes generation of embryos by nuclear transfer, altered nuclear transfer, activation of gametes and parthenogenesis.

Unlike other requirements for patentability, adding features to a claim cannot rescue a claim that falls foul of this exception — one feature, irrespective of all other features, is enough to render a claim unpatentable.

However, in International Stem Cell Corporation [2016] APO 52, the Patent Office decided recently that an embryo generated by parthenogenesis did not contravene the exclusion because under no circumstances could the “embryo” generate a human being. 

In theory, if other processes such as nuclear transfer are employed that generate an “embryo” that cannot become a human being, they too should be patentable. This is yet to be tested.

Antibodies

While antibodies are patentable in Australia, changes to Australian patent law in 2013, known as Raising the Bar, have tightened the requirements.

Whereas prior to April 2013 antibodies could be defined by as few as one CDR, standard antibodies must now be claimed by defining at least three heavy chain CDRs and at least three light chain CDRs.

Claiming antibodies defined by their competition with another antibody for an epitope is possible, but at least requires the epitope to be novel and inventive and defined structurally in the claim.

Summary

At least with respect to nucleic acids, it appears that Australian patent practice now is more restrictive than that of the US under the US prohibition of patenting products of nature. For example, cDNA is no longer patentable in Australia, but remains patentable in the US.

At the same time, patent practice surrounding stem cell technologies appears to be evolving in step with the technologies. Interestingly, this evolution of patentable subject matter exclusions reflects the evolution that was always intended for non-excluded patentable subject matter (see National Development Research Corporation v Commissioner of Patents [1959] 102 CLR 252).

Finally, Australian patent practice with respect to antibodies is now generally consistent with that of other jurisdictions, notably Europe.

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