PATTEN AND THE PARENTERALS

In Sandoz GmbH v Roche Diagnostics GmbH, decided Thursday by Mr Justice Patten and noted on the useful All England Direct subscription-only service, Roche owned a patent relating to ways in which injectible liquid formulations ("parenterals"), which had proteins as their active ingredient, could be effectively preserved when prepared for multi-dose application. The patent claim specified the use of three particular antimicrobial preservatives, either alone or in combination, at a concentration of up to 2% in the solution. Roche later applied to amend its patent in order to restrict the claims to formulations which contained just one particular protein (erythropoietin) and which utilised a combination of two or more of the three specified preservatives rather than any one of them singly. Sandoz objected, maintaining that the amended claims did not disclose any inventive step. It sought the revocation of the patent for obviousness, on the grounds of common knowledge and prior art.The court had to decide whether the process set out in the amended claims involving the combination of low concentrations of two or more of the three selected preservatives was obvious at the priority date.

Patten J dismissed the claim. For something to be obvious to try, the court had to be satisfied that the skilled addressee would have tested it as something which held out a prospect of producing valuable results. He was not taken to be someone who carried out trials for the sake of doing so: what had to be shown was that the skilled addressee didn't think the likelihood of success was certain but that it was at least worth trying. On the evidence, Sandoz's contentions as to obviousness were not made out.Accordingly, the action for revocation of the patent would fail.

The IPKat thinks this is a particularly clear exposition of the notion of "obvious to try" as a parameter for the measurement of inventive step.

More on erythropoietin here, here and here
Parenterals here and here
Other things worth a try here, here and here