The UK House of Lords has now handed down a judgment further explaining its 1997 decision in Biogen v. Medeva in a way that significantly limits the scope of Biogen and provides clarity as to the way in which inventions, particularly in the field of biotechnology, are best claimed in the United Kingdom and Europe. Generics (UK) v. Lundbeck [2009] UKHL 12 (Feb. 25, 2009).

The Generics case concerned Lundbeck’s patent for the product escitalopram. Escitalopram is a successor to the product citalopram and is used as an antidepressant. Citalopram is a racemate consisting to two enantiomers. Enantiomers are pairs of molecules that have the same chemical formula and the same three dimensional structure but one is the mirror image of the other; they are conventionally distinguished by the prefix (+) or (-).

What was not known prior to the teaching of the patent in issue in the present case was how to separate the (+) and (-) enantiomers of citalopram and, therefore, their respective contributions to the antidepressant quality of citalopram. Lundbeck devised a method of separating the (+) and (-) enantiomers and discovered that it is the (+) enantiomer that has the desired antidepressant effect, and that the (-) enantiomer has, if anything, an inhibiting effect. A much more effective antidepressant is, therefore, achieved by isolating and marketing the (+) enantiomer of citalopram. Lundbeck filed for a patent claiming the (+) enantiomer (escitalopram) on its own.

It was this point that the decision in Biogen kicked in. The Court of First Instance accepted that the (+) enantiomer on its own was a novel entity since previously it had only existed in combination with its “twin.” However the court also held that, as of the priority date, the separation of the enantiomers was “a known desideratum” and obvious. The court further determined that Lundbeck’s contribution to the art was to discover one way of achieving the separation, but at the same time there could well be other ways. On that basis the court ruled that a claim to the (+) enantiomer per se fell afoul of § 14(3) of the UK law that provides that “the specification … shall disclose the invention in a manner which is clear enough and complete enough for the invention to be performed by the person skilled in the art.” Previous cases determined that this provision should be read in conjunction with § 14(5)(c), which provides that the claims or claims should be “supported by the description.” Thus, the court reasoned, the claims (at issue in Biogen) were not supported by the description since they sought to monopolize a molecule that was a known desideratum in a situation in which the patentee had only disclosed one way of making that molecule and there could be other ways of making it which owed nothing to the teaching of the patent. Put another way, the court held that the technical contribution (i.e., the discovery of one way of making the molecule) did not justify the breadth of the monopoly claimed. While the patentee might be entitled to a patent for its initiative process, it was not entitled to claim the product itself, which was known.

What emerged from the appeal is an understanding that, for the past 12 years patent practitioners in the UK had taken a completely erroneous view of the scope of Biogen. As explained by Lord Hoffmann in the initial level of appeal (the Court of Appeal) and now confirmed by the House of Lords, Biogen was explicable by its particular facts. Of crucial importance was that in Biogen the claims in issue were product by process claims. In Biogen, the inventor had simply taken large strands of the Dane particle DNA, put them into a standard recombinant plasmid, transfected a prokaryotic cell and caused that cell to express the genes of the hepatitis B antigens. He had not sequenced the DNA. However the claims sought by Biogen would monopolize the molecule made by any process of recombinant technology. Thus, the House of Lords found the patent to be insufficient in that the specification did not provide support for whole breadth of the claims.

By contrast, the Lundbeck patent claimed only the product per se. The judges ruled that the disclosed product’s novelty was Lundbeck’s contribution to the art. Once a patentee had disclosed a new product and one way in which it can be made, he was entitled to claim that product per se, even if there were other ways by which the product could be made. Accordingly, the allegation of insufficiency was rejected. The crucial distinction was between a product by process claim on the one hand (where a patentee would be limited to claims for products made by that process) and product claims per se (where all the patentee had to do was to show one way of making a novel product and he was then entitled to a monopoly for that product).

Practice Note: At least in the UK, patentees should, so far as possible, avoid framing their inventions as product by process claims and, whenever possible, strive to disclose a novel product, how it can be made and then claim the product per se.