On 6 October 2004, Gyles J. of the Federal court handed down Arrow v Merck 63 IPR 85. This case involved many issues. I focus on the lesson it gives in defining patentable subject matter.
The first hurdle in a patentability investigation is to establish what actually is patentable subject matter. In other words, the actual subject of the patent application must be a "manner of manufacture" as set out in the Patents Act and as defined and re-defined in many cases. Over the years, the courts have held that it is not possible to claim as an invention a new use for a known product where the known properties of the product would make it suitable for that use.
Merck was the holder of Australian patent No. 625704 for specific alendrate monosodium trihydrate species. The patent also covered a method of treating osteoporosis using this chemical. The patent was due to expire in 2010. In an attempt effectively to extend its protection (known as "evergreening"), Merck applied for and was granted Australian patent No. 741818. The second patent was directed primarily to a method of inhibiting bone resorption such as osteoporosis using the alendrate described in the first patent. The second patent also claimed a composition "adapted" for oral administration. The composition itself was already described in the first patent and the second patent attempted to cover the composition so adapted.
Arrow applied for revocation of the claims (and thus effectively of the patent) on a number of grounds including lack of subject matter of the claims.
In revoking the claims, Gyles, J. held that the method claimed was a direction to use a composition that was already known to be effective for that use. In other words, the "method" claims were simply a use of a known substance with known properties for a known purpose. Gyles J. also held that the "composition" claims were "devoid of practical content". He held that the composition as claimed was not a "new and unique" compound and did not "adapt" to once weekly dosing as compared to any other dosing.