On 15 March 2013, the Australian Federal Court upheld Eli Lilly's patent for the active compound in their highly successful product ZYPREXA®. Lilly successfully defended the validity of the patent against a wide-ranging attack by the well-known generic pharmaceutical manufacturer Apotex. Wrays is pleased to have been able to work together with Ashurst Australia in achieving this outcome for Eli Lilly.
The compound in question, olanzapine, was encompassed by an earlier Eli Lilly patent – a 'genus patent'. However, olanzapine was not explicitly disclosed in the earlier patent, and was argued to have superior properties to those compounds that were explicitly disclosed. The later patent, in such a situation, is commonly known as a 'selection patent'. Apotex cited the genus patent against the novelty of Eli Lilly's olanzapine, thereby providing the Australian Court with the opportunity to provide certainty on the status of selection patents in Australia. However, the Court expressly declined to do so, deciding the issue of novelty in favour of Lilly based on standard novelty principles around the quality of the prior disclosure. Nonetheless, the decision provides a useful example of how established selection patent principles would be applied to the patent in question: should such principles apply, the patent would be valid.
The decision provides some welcome commentary on the interplay between two key concepts of inventive step law in Australia, at least in the context of the Patents Act 1952. The key concepts are the starting point of the inventive step inquiry (which the court confirmed was the same concept as the "problem to be addressed") and the common general knowledge. Apotex submitted that the two concepts are distinct – that the starting point may involve information that is not part of the common general knowledge in Australia. However, the Court clearly disregarded knowledge that did not form part of the common general knowledge as "irrelevant to the question of inventive step", and rejected the universal applicability of the "problem-solution" approach to inventive step.
Interestingly, and somewhat unusually in the context of generic-innovator patent disputes, the issue of infringement was very much alive in this case. The claims of the patent identify olanzapine by way of a name only (no chemical structure appears in the claim to the compound), and it was agreed that the name used was not the name that would be generated for the compound by strict adherence to the nomenclature principles set down by the International Union of Pure and Applied Chemistry (IUPAC). However, elsewhere in the specification, the name used in the claim was clearly associated with a chemical structure that unambiguously represented olanzapine. The Court expressly rejected any approach that required the claims to be construed in isolation from the specification as artificial, finding that a skilled addressee would clearly identify olanzapine as the compound claimed, and thus finding that the Apotex products infringed Eli Lilly's patent.