Following his SPC decisions earlier this year (noted in our recent edition of Inside Life Sciences), Arnold J has once again been called upon to interpret Article 3(a) of the SPC Regulation. The SPC relates to darunavir (sold under the mark Prezista) and concerns a Markush claim, i.e., where a class of compounds is represented by means of a structural formula, thereby allowing large classes of compounds to be defined without being listed out.
Arnold J decided in this case (Sandoz v G.D. Searle) that the product is specified or identified in the claims of the Patent, and rejected the Claimants' request for a reference to the CJEU. The Claimants argued that darunavir was not specified or identified in any of the claims of the Patent – they argued that, whilst it fell within the claims due to their immense breadth, it was not specifically identified by name or structure in the claims or anywhere in the specification, nor was there any teaching in the Patent which pointed to darunavir and in particular its novel and unusual P1 group. The Claimants argued that a Markush claim does not specify or identify a product, unless the skilled person would consider the product to be part of the subject matter of the Patent based on their reading of the specification and their common general knowledge as at the priority date without undue burden, or further invention. However, they accepted that this was not an acte clair interpretation of Article 3(a) and sought a reference to the CJEU.
Arnold J agreed with the Defendants that darunavir was protected by the Patent, and therefore no reference to the CJEU was necessary. He referred to the CJEU's Lilly decision where it had decided that it is not necessary for the active ingredient to be identified in the claim by means of a structural formula: it is sufficient for it to be covered by a functional description provided that the claims "relate, implicitly but necessarily and specifically, to the active ingredient". Accordingly, he concluded, the identification of the active ingredient in the claim by means of a structural formula is permissible, but not essential. Further, it is not necessary for the claim individually to name or depict the active ingredient and it is also not necessarily an objection that the claim covers a large number of other compounds in addition to the active ingredient in question. Whilst he had indicated in Gilead that the test laid down in Lilly with respect to functional descriptions is unclear and difficult to apply, he concluded that this did not matter in this case. The key point was that the decision in Lilly had shed light on the Medeva test and suggested that it was sufficient for the claim to specify the product by means of a Markush formula which covers it - at least without resort to equivalents.