CSL Ltd v Novo Nordisk Pharmaceuticals Pty Ltd (No 2)

CSL Limited and Monash University, the proprietors of Australian Patent No 716,747, have brought an application under s 105 of the Patents Act 1990 (Cth) to amend claims 1 and 3 of the patent. The respondents, Novo Nordisk Pharmaceuticals Pty Ltd, Novo Nordisk A/S and Novo Nordisk Health Care AG, oppose the application. The patent, which was granted on 12 January 2000, is for a stabilised growth hormone and a method of preparation thereof. The applicants allege that the respondents have infringed certain claims in the patent, and the respondents allege that the invention was not novel, and that it lacked an inventive step. The applicants applied for a direction that the patent be amended pursuant to s 105 of the Patents Act. The amendments sought involved the introduction of new text into claim 1 of the patent, and the deletion of existing text from claim 7. The applicants also sought the making of an amendment to correct a typographical error in claim 3 of the patent as registered, and there was no opposition to that. The question remaining for the court, therefore, is whether the broad discretion which arises under s 105(1) should be exercised favourably to the applicants. The grant of the patent in suit arose from the filing by the applicants of an Australian Provisional Specification (No. PN 8012) on 12 February 1996. An international application based on the provisional specification was filed under the Patent Co-Operation Treaty on 12 February 1997 under No. PCT/AU97/00075. It designated all countries and regions party to the PCT, including Australia. It claimed priority from the Australian Provisional Specification. The applicants engaged Davies Collison Cave (“DCC”), a firm of patent and trade mark attorneys, to assist with the filing of patent applications in specific jurisdictions. Mr John Slattery was the partner at DCC who had responsibility for the prosecution of these applications down to late 2007 or early 2008, when that function was taken over by another partner at DCC, Dr Bill Pickering. Mr Slattery seems to have had some ongoing involvement as a consultant. The applicants filed applications in Australia, Europe, the United States of America, Russia, Canada, China, Japan, Turkey and Hong Kong. Aside from the application which gave rise to the patent in suit, only the applications in the United States and in Europe, Russia and Canada are presently relevant. The applicants were the ones who tendered such relevant documents as did find their way into the evidence, but those documents identified themselves by reason of having been provided by the applicants on discovery, at the behest of the respondents. The patchy nature of the documentary history thus presented justifies the inference, which I draw, that there were other documents – correspondence, for instance – which related to these applications and which have not been placed into evidence. In the application filed under the PCT, claims 1 and 7 were as follows:1.A method for the preparation of a stable, liquid formulation of growth hormone, comprising growth hormone, a buffer and a stabilising effective amount of at least one stabilising agent selected from the group consisting of:(i)polyethylene-polypropylene glycol non‑ionic surfactants,(ii)taurocholic acid or salts or derivatives thereof, and(iii)methyl cellulose derivatives,wherein the method comprises admixing the growth hormone with the buffer and the stabilising agent(s) under conditions such that the growth hormone is not exposed to concentrations of the buffer or stabilising agent(s) which are greater than 2x the final concentrations of the buffer or stabilising agent(s) in the formulation.7.A method according to any of claims 1 to 6, wherein the pH of the formulation is from 5.0 to 7.5, preferably 5.0 to 6.8, more preferably from 5.2 to 6.5, and most preferably from 5.4 to 5.8.The Australian, European and United States claims 1 and 7, in their original forms, are not in evidence. However, as appears from the claims as granted in Australia (see para 2 above), only with respect to the stabilising agents listed in the first subparagraph of claim 1 do those claims relevantly depart from the corresponding claims set out in the PCT application. Nothing presently turns on that distinction, and I am disposed to infer that the applications in each of Australia, Europe and the United States followed closely the terms of the PCT application. The Australian Patent Office, acting as the international searching authority for the PCT, issued an international search report for the PCT application on 16 April 1997. Of the six prior art documents cited in that report, two were described as “defining the general state of the art which is not considered to be of particular relevance”. Those citations (which are amongst the citations relied on by the respondents in their Particulars of Invalidity) were identified as “D1” and “D2” in the present proceeding. D1 is European Patent Application No. 86305824.4 which resulted in European Patent No. 0 211 601 said by the respondents to have been open for public inspection at the Australian Patent Office, Canberra on 24 March 1987 (and the corresponding Australian Patent Application No. AU 60733/86 S published 5 February 1987 and the corresponding Japanese Patent Application No. 070319/1987). D2 is an article entitled “Effect of Surfactants on the Physical Stability of Recombinant Human Growth Hormone” by Katakam M. et al, published in 1995 in the Journal of Pharmaceutical Sciences Vol 84 No. 6 pp 713-716, and said by the respondents to have been available to the public in Australia at the C L Butchers Pharmacy Library, Monash University on 19 July 1995. The search report of 16 April 1997 described D1 also as a “document of particular relevance, the claimed invention cannot be considered novel or cannot be considered to involve an inventive step when the document is taken alone”. Notwithstanding these reservations, on 16 January 1998, an international preliminary examination report was issued which cited D1 (but not D2), and in which the examiner found that claims 1-9 of the PCT application were novel and involved an inventive step on the basis that none of the prior art citations specifically disclosed the concentration limitations of the growth hormone, buffer and stabilising agents as claimed in those claims. In Australia, the examiner’s first report was issued on 3 September 1998. The examiner concluded that there were lawful grounds of objection to the application, including that claims 1-9 lacked an inventive step in light of prior art citations which included D1. The examiner gave the applicants 21 months to overcome these objections. In Europe, following the submission of amended claims 1-