Past interpretation no guarantee of future performance

The topsy-turvy world of patent construction got a little bit more topsy-turvy this week with a neat little ruling on whether a trial court was bound by an earlier trial court's interpretation of a litigated patent. That ruling was Novartis AG v Dexcel-Pharma Ltd [2008] EWHC 1266 (Pat), a decision of Mr Justice Floyd this Tuesday.

Novartis owned a patent for 'pharmaceutical compositions containing cyclosporins', these being a class of immunosuppressive drugs which were important in the treatment of transplant patients since they helped prevent the rejection of transplanted tissue. Cyclosporins did not dissolve very well in aqueous media, which reduced their bioavailability. Novartis's patent was for a novel cyclosporin formulation in the form of a micro-emulsion pre-concentrate.

Dexcel wanted to launch a new pharmaceutical product comprising a cyclosporin as its active ingredient. Novartis said this infringed its patent and sought interim injunctive relief. Dexcel was not deterred, arguing that, on the basis of the construction of the same patent in earlier litigation, there was no serious question to be tried on the issue of infringement.

Floyd J allowed the application for interim injunctive relief. In his view it was seriously arguable that a subsequent court was not actually bound by a previous court's conclusion as to the correct construction of a patent specification where the earlier conclusion depended on evidence which was either lacking in the previous case or materially different in the later case. In this instance, the question as to whether Dexcel's product infringed was a serious issue which fell to be tried. Both parties conceded that the other would suffer unquantifiable loss if the 'wrong order' was made. Nonetheless, the balance of convenience fell in favour of granting the injunction to stop Dexcel from marketing its product until the infringement issue was determined.

The IPKat says, how exciting this all is. First the Court of Appeal whittles down the ambit of res judicata (see the IPKat here); then it says it's not bound by its earlier decisions if they no longer fit European Patent Office doctrine (see the IPKat here); now previous interpretations of patents can be cast aside too. Merpel says: it's the usual trade-off between (i) justice in the individual case and (ii) predictability of the judicial process. Which would you pay more for, any why?