Methods of medical treatment patentable in Australia

Today the High Court, the highest court in Australia, held by majority that methods of medical treatment of the human body are patentable inventions.  It also held that there was no contributory infringement in circumstances where the patented indication was specifically excluded from the product information sheet of a pharmaceutical.


The  leflunomide compound, marketed in Australia under the trade name ‘Arava’, was the subject of Australian patent 529341 to Sanofi.  The leflunomide product patent, which expired in 2004, referred to the use of leflunomide to treat ‘rheumatic complaints’.  At the time the patent was filed, the most common rheumatic complaints included rheumatoid and psoriatic arthritis.  Originally, Sanofi only registered leflunomide on the ARTG as a treatment for rheumatoid arthritis.  Following successful clinical trials in 2004, the Arava registration was extended to cover psoriatic arthritis.  However, the product information sheet stated that ‘Arava is not indicated for the treatment of psoriasis that is not associated with manifestation of arthritic disease’.

A further Australian patent, AU 670493, also to Sanofi, claims a subsequent medical use for leflunomide.  This patent is set to expire on 29 March 2014 and has a single claim directed to the use of leflunomide for the treatment of the skin disorder, psoriasis.  This medical use was not envisaged in the original patent.  The ‘second medical use’ patent effectively secured Sanofi a monopoly over the use of leflunomide for the treatment of psoriasis until 2014, even though it is not registered in Australia for this indication.

Apotex obtained registration of its generic product ‘Apo-Leflunomide’ in July 2008 with the intention of marketing the product for the treatment of rheumatoid and psoriatic arthritis.  Sanofi then commenced proceedings in the Federal Court, claiming that Apotex threatened to infringe claim 1 of AU 670493.  Apotex, in response, alleged that the patent was either invalid or not infringed.

Decision at first instance (1)

In the original trial, the primary judge found the patent to be valid and infringed.  Accordingly, Apotex was restrained from marketing or supplying any products that contained leflunomide.  Her Honour stated that ‘if leflunomide is administered to a patient with psoriatic arthritis, that administration would be expected to prevent or treat the patient’s psoriasis, to some extent at least’.  The patent was found to be infringed because of the effect of the drug, even though it was not prescribed for the treatment of psoriasis (so called ‘off-label’ use).  Apotex appealed this finding, arguing that the patent was directed to a method of preventing or treating only the specified skin disorder, psoriasis.  It was also argued that the patent was invalid for lack of novelty.

Appeal decision (2)

In July 2012, the Full Court of the Federal Court unanimously dismissed Apotex’s appeal.  Their Honours found that the patent was not invalid for lack of novelty and rejected the arguments that the patent claim covered any administration of leflunomide that happened to result in the treatment of psoriasis.  The Court held that the planned supply of Apo-Leflunomide would infringe the patent as the product information would effectively cause leflunomide to be used for the treatment of psoriasis.

Apotex was subsequently granted special leave to appeal this decision to the High Court of Australia.

High Court Decision (3)

The primary question considered in this case was whether methods of medical treatment of human beings, including administration of therapeutic drugs and surgery, are proper subject matter for a patent in Australia. The High Court has not had to decide the question until now. The judgement, released today, answers this question in the affirmative.

Patentability of methods of medical treatment

It was held, by majority, that Sanofi’s ‘medical use’ patent claimed a ‘manner of manufacture’ within the meaning of s 18(1) of the Australian Patents Act 1990. Chief Justice French stated at [50]:

‘The exclusion from patentability of methods of medical treatment represents an anomaly for which no clear and consistent foundation has been enunciated. Whatever views may have held in the past, methods of medical treatment, particularly the use of pharmaceutical drugs, cannot today be conceived as “essentially non-economic”… In my opinion the application of the rubric “manner of new manufacture” in a logically and normatively coherent way is not served by excluding from its scope methods of medical treatment of human beings.’

Similarly, Justice Hayne stated at [177]:

A method claim, for the administration of a pharmaceutical substance (with prior therapeutic uses) for a hitherto unknown therapeutic use, can be a patentable invention’.

The High Court recognised that the field of intellectual property law is one in which there is a tension between alleged incentives to innovation on the one hand, and the widest possible availability of new methods of medical treatment to relieve suffering on the other.  However, these questions were ones for the legislature and not the court.  Chief Justice French stated at [50]:

‘To decide that the concept of “manner of new manufacture” does not logically exclude methods of medical treatment from patentability does not engage with those large questions, although it may have significant consequences for public policy. This is a case in which such considerations are best left to the legislature.’

Chief Justice French also recognised that there is difficulty in drawing a boundary between medical and cosmetic procedures, stating at [44] that:

‘…the latter may include procedures having both medical and cosmetic benefits: for example, lap band surgery’.

The application for revocation initiated by Apotex was accordingly refused on the basis that claim 1 disclosed a patentable invention.

‘Off-label’ infringement

On the question of infringement, it was found that Apotex’s proposed supply of Apo-Leflunomide did not infringe the Sanofi medical use patent.  Sanofi’s claim of infringement rested on s 117 of the Patents Act 1990, which sets out the conditions under which a supply of a product will constitute an infringement of an indirect or contributory kind. The product information document for Apo-Leflunomide stated that:

‘Apo-Leflunomide is indicated for the treatment of:
. Active Rheumatoid Arthritis.
. Active Psoriatic Arthritis. Apo-Leflunomide is not indicated for the treatment of psoriasis that is not associated with manifestations of arthritic disease.’

The court held that Apotex’s approved product information document did not instruct recipients to use the unpatented pharmaceutical substance in conjunction with the patented method.  Therefore the product information document did not engage s 117(2)(c) of the Patents Act 1990. It could not be inferred or shown  (at [304]) ‘…that Apotex had reason to believe that the unpatented pharmaceutical substance, which it proposes to supply, would be used by recipients in accordance with the patented method, contrary to the indications in Apotex’s approved product information document’.

This would suggest that the practice of excluding indications from the product information sheet of therapeutic drugs should be a successful defence against infringement, at least in similar circumstances to those of the present case.


  1. Sanofi-Aventis Australia Pty Ltd v Apotex Pty Ltd (No 3) [2011] FCA 846
  2. Apotex Pty Ltd V Sanofi-Aventis Australia Pty Ltd (No 2) [2012] FCAFC 102
  3. Apotex Pty Ltd V Sanofi-Aventis Australia Pty Ltd & Ors [2013] HCA 50

If you have any specific enquiries about the leflunomide case in Australia, please contact Paul Jones or Debra Tulloch.

This article was written by Dr Ellen Reid.