ratiopharm/Sandoz v Napp Pharmaceuticals

Last week, Mr Justice Floyd delivered his judgment in the case of ratiopharm & Sandoz v Napp Pharmaceuticals, but the IPKat has been taking a while to digest this very long and complicated judgment.  The case related to two of Napp's EP(UK) patents for sustained release formulations for the painkiller drug oxycodone, more commonly known (at least to Rush Limbaugh) by the trade mark OxyContin.  

Sandoz and ratiopharm (not to be capitalised, apparently) had applied to revoke the two patents, EP0722730 and EP1258246 (derived from a common priority application) on the grounds that the claimed invention in both was obvious. Napp counter-claimed for infringement.  The invention, which was not at all easy to identify, came down to the particular way in which the claimed formulation provided an extended release of oxycodone over time, apparently allowing a more controlled dosage within specified limits.  This was achieved by having an oxycodone salt mixed into a resin matrix in the form of a spheroid, with an outer coating to control release of the salt.  

Strangely enough, given that the case was kicked off by actions for revocation, the main issue came down to whether the alleged infringing product, in the form of a multi-layered particulate form of oxycodone (pictured left in cross-section) did actually infringe any of the claims in question.  The alleged infringement was based on a central (non-pharmaceutical) core, surrounded by three layers having different functions, the first and third of which (inner and outer layers in the picture) contained oxycodone. The outer layer, containing about 20% of the total amount of oxycodone, would provide an initial dose, while the rest of the drug, bound up in the inner layer, would release over time by diffusing out through the polymer layer. 

Probably the easist of the claims in question to understand was the following one, claim 6 from EP0722730:

A controlled release oxycodone formulation for administration to human patients, comprising:
(a) an analgesically effective amount of spheroids comprising oxycodone or a salt thereof and a spheronising agent;
(b) each spheroid being coated with a film coating which controls the release of the oxycodone or oxycodone salt at a controlled rate in an aqueous medium.

Construction of the claims was a question best answered with reference to the familiar approach offered by Lord Hoffmann in Kirin Amgen:

"Construction, whether of a patent or any other document, is of course not directly concerned with what the author meant to say. There is no window into the mind of the patentee or the author of any other document. Construction is objective in the sense that it is concerned with what a reasonable person to whom the utterance was addressed would have understood the author to be using the words to mean. Notice, however, that it is not, as is sometimes said, "the meaning of the words the author used", but rather what the notional addressee would have understood the author to mean by using those words. The meaning of words is a matter of convention, governed by rules, which can be found in dictionaries and grammars. What the author would have been understood to mean by using those words is not simply a matter of rules. It is highly sensitive to the context of and background to the particular utterance. It depends not only upon the words the author has chosen but also upon the identity of the audience he is taken to have been addressing and the knowledge and assumptions which one attributes to that audience." (paragraph 32)

Floyd J concluded, after extensive analysis of the wording of the claims, that the claims in question required either all the oxycodone to be included in the matrix, and not in the outer layer, or that a spheronising agent (i.e. something that allowed a spherical particle to be formed) was required in the formulation. Neither of these constructions could be used to cover the alleged infringement, since the particle did not have a spheronising agent (the central non-active core was pre-made, and not judged itself to be such an agent), and a significant proportion of the active ingredient was in the outer layer of the particle.

Floyd J went on to conclude that the patents were valid, and not obvious in light of the cited prior art (though the IPKat wonders how valuable they are now, if they can be worked around so easily).

The IPKat thinks that this case demonstrates that there are cases where meticulous verbal analysis is definitely required to figure out what a patent actually claims, as otherwise it would be difficult to show where the boundaries of the invention lie. It didn't help, however, in this case that some of the claims were apparently (in the words of Floyd J) "very poorly drafted", making the task of figuring out what they meant even more difficult than usual. This might be an effect of hindsight, but the IPKat wonders why, for such an important (i.e. money making) drug, the claims in this case were not drafted better.  Could Napp not afford a patent attorney who understood how to draft dependent claims? And how did this get past Article 84 requirements at the EPO?