Australian High Court Rules Rosuvastatin Low Dose Patent Obvious
In an eagerly awaited decision¹ the Australian High Court has upheld a decision of a five judge bench of the Full Federal Court that AstraZeneca’s patent relating to low dosages of rosuvastatin is invalid on the basis that the claims lack an inventive step.
Section 7(3) of the Patents Act 1990 (Act) as it existed at the priority date of Astra Zeneca’s patent imposed a threshold requirement that in order to be considered for assessing inventive step a document must be “ascertained, understood and regarded as relevant” by a person skilled in the art.
Astra Zeneca (AZ) argued that where multiple documents meet the threshold requirement it is impermissible to determine inventive step on the basis that the only avenue available to the skilled person is that in one of the multiple documents. To do so was said to create “a new revoker’s starting point with the benefit of hindsight” and avoided false routes suggested by other documents.
The High Court rejected this argument noting that the relevant language of the Act (i.e. section 7(2) which sets out the test for inventive step) does not support the limitation contended by AZ. It was confirmed that different prior art documents may be considered separately as long as they meet the threshold requirement. This is clearly consistent with the purpose of section 7(2).
AZ further argued that the language of sections 7(2) and 7(3) place limitations on the process by which a skilled person may determine whether a document would have been “ascertained, understood and regarded as relevant”. Specifically, AZ argued that comparing documents not part of the common general knowledge for the purpose of establishing the threshold test and identifying a document as “the” relevant course to pursue “subverts the purpose of Section 7(3) and is impermissible”.
The High Court disagreed and echoed the Full Court’s earlier view² that the skilled person may well sort through all manner of information with a view to finding something that is regarded as relevant, and that section 7(3) places no embargo on the skilled person using combinations of sources of information.
Of additional interest is the fact that the High Court did not disturb the Full Court’s finding that information against which inventive step may be assessed is not to be enlarged by reference to the description in the body of the specification. One practical effect that follows from this is that where a problem underlying an invention is unknown at the priority date the problem will not form the starting point, or otherwise be taken into consideration, when assessing inventive step. This objectivity in assessing inventive step may, in some circumstances, provide an advantage for innovator companies (for example innovator pharmaceutical companies) where they are the only ones aware of the particular problem at the priority date.
¹ AstraZeneca AB v Apotex Pty Ltd; AstraZeneca AB v Watson Pharma Pty Ltd; AstraZeneca AB v Ascent Pharma Pty Ltd  HCA 30 (2 September 2015) http://www.austlii.edu.au/au/cases/cth/HCA/2015/30.html
² AstraZeneca AB v Apotex Pty Ltd  FCAFC 99 (12 August 2014) http://www.austlii.edu.au/au/cases/cth/FCAFC/2014/99.html