In the High Court: the patentability of methods of medical treatment

The High Court today delivered judgment in Apotex Pty Ltd v Sanofi-Aventis Australia Pty Ltd [2013] HCA 50. 

Sanofi-Aventis was the registered owner of a patent which claimed a method of preventing or treating psoriasis by the administration of the drug called leflunomide.  Apotex intended to supply leflunomide in Australia, under the trade name “Apo-Leflunomide”, for the treatment of rheumatoid arthritis and psoriatic arthritis.  In answer to proceedings claiming infringement of the Sanofi-Aventis patent, Apotex sought to have the patent revoked.  While Apotex accepted that a person could claim a patent with respect to the discovery of a new drug (a product claim), the same could not be said for a person who merely discovered a new use for that drug (a method claim).

By majority (French CJ, Crennan and Kiefel JJ, and Gageler J) the High Court held that a method (or process) for medical treatment of the human body which is a contribution to a useful art having economic utility, can be a manner of manufacture and hence a patentable invention under section 18 of the Patents Act 1990 (Cth).  In the case of a claimed patent for a novel use of an existing therapeutic drug, those criteria are readily satisfied, and accordingly Sanofi-Aventis’ patent was valid.  There could be no rational economic or ethical distinction drawn in this context between a product claim by the inventor of a new drug, and a method claim by the discoverer of a new use for an existing drug.

There is a suggestion in the judgments that there may be a distinction between a method of medical treatment which involves a novel therapeutic use of a drug (having prior therapeutic uses) and the activities or procedures of doctors (and other medical staff) when physically treating patients. This is because, speaking generally, they may be regarded as “essentially non-economic" and not “susceptible” or “capable” of industrial application. To the extent that such activities or procedures involve “a method or a process”, they are unlikely to be able to satisfy test for the patentability of processes because they are not capable of being practically applied in commerce or industry.

Ultimately, however, the High Court allowed the appeal because it held that even though Sanofi-Aventis’ patent was valid, Apotex’s intended supply did not infringe the patent.  The alleged infringement was based upon section 117 of the Act, which provides that is use by a person would infringe a patent, then supply of the product by one person to another will also amount to infringement.  However, the reference to “use by a person” is defined to mean “the use of the product in accordance with any instructions for the use of the product, or any inducement to use the product.” The product information approved by the TGA for use by Apotex expressly provided that while “Apo-Leflunomide” was indicated for the treatment of active psoriatic arthiritis, it was not indicated for the treatment of psoriasis that is not associated with manifestations of arthritic disease.