Extending the patent term for drug delivery systems: muddying the waters of the meaning of “pharmace
LTS Lohmann Therapie-Systeme AG and Schwarz Pharma Limited  AATA 809
The Administrative Appeals Tribunal (AAT) recently affirmed the Australian Patent Office’s decision in LTS Lohmann Therapie-Systeme AG and Schwarz Pharma Limited ( APO 16), as reported in our IP Update, October 2009, to refuse an extension of term for a transdermal therapeutic system (transdermal patch) to deliver rotigotine for treating Parkinson’s syndrome (Neupro®).
At first instance, the Deputy Commissioner held that claim 1 of the patent defined a transdermal patch comprising three components: a polymer matrix containing rotigotine, an inert backing layer, and a protective layer to be removed before use. The primary issue considered at first instance was whether the transdermal patch of claim 1 as a whole is a “pharmaceutical substance per se”. Pursuant to s 70(2)(a) of the Patents Act 1990, a patentee can apply for an extension of term of a patent if a pharmaceutical substance per se is in substance disclosed in the patent and falls within the scope of the claims.
In reaching the decision the Deputy Commissioner took guidance from the N. V. Organon ( APO 8) case which broadened the meaning of “a pharmaceutical substance per se” to encompass drug delivery systems that have “a level of integration or interaction” between the component parts of the system provided that the characteristics of what is claimed predominantly lie with it being a substance rather than a substance in combination with a separate physical device, layer or structure. The Deputy Commissioner observed that the presence of an inert backing layer and protective layer would not be fatal if the patentee could demonstrate that the product as a whole shows a level of integration or interaction between the component parts such that it would fall within the definition of a pharmaceutical substance. Ultimately, however the Deputy Commissioner considered that in the case of Neupro® the protective layer, which is removed before use, does not integrate or interact in any way with the other parts of the transdermal patch and the “presence of this layer at least”, was held to render the transdermal patch a pharmaceutical substance in combination with a separate integer. Accordingly, the extension of term was refused.
In making the appeal, the patentee sought to rely on the N. V. Organon decision to support the contention that Neupro® is a pharmaceutical substance per se. This position finds basis in the Sanofi-Aventis ( APO 35) case in which it was held that a compound includes “a compound that is formed by combining elements or parts, or creating a union of parts”.
The patentee also attempted to argue that because the claims of the patent are directed to a pharmaceutical compound they are distinguishable from the Euro Celtique S. A. ( APO 13) case which concerned an extension of term for a patent which claimed a transdermal delivery system containing buprenorphine (Norspan®). In Euro Celtique, S. A. an extension of term was refused because of the implied presence of a backing layer. In other words, the transdermal delivery system represented a “separate physical integer unrelated to the mixture of chemical entities”. Relevant here, however, was that the original claims of the present case were to a transdermal therapeutic system and were subsequently amended to claim a pharmaceutical compound. In this regard, Downes J at the AAT noted that, despite the amendments to the claims, the patent specification still indicated that the “invention relates to a transdermal therapeutic system for the treatment of Parkinson’s syndrome”.
In considering the terms “pharmaceutical substance” and “pharmaceutical substance per se” Downes J reviewed some of the relevant previous decisions. His Honour cited with approval Euro Celtique, S. A. and the LTS Lohmann Therapie-Systeme GmbH & Co KG ( APO 12) case in which a transdermal patch to deliver the known drug 17-b-estradiol was refused an extension of term because it was held that a pharmaceutical substance is “necessarily limited to chemical entities per se, compounds of chemical entities, and mixture of chemical entities” and that “if a claim to an alleged pharmaceutical substance includes features specifying the spatial configuration of the entities in the substance, it is not a claim to a pharmaceutical substance per se but a claim to an arrangement of substances characterised by that spatial configuration”.
The reasoning in Boehringer Ingelheim International GmbH v Commissioner of Patents ( FCA 674), which held that a patent term extension is only available for a “new and inventive substance” and not for a known substance which forms part of a new method of delivery or process, was also cited with approval.
In essence and somewhat surprisingly, Downes J cited only those cases in which a strict interpretation of a pharmaceutical substance per se as a chemical entity or mixture of chemical entities was applied. Notably, there was no consideration of the Sanofi-Aventis case. Accordingly, in coming to his decision Downes J took a narrow view of the term “pharmaceutical substance per se” stating that the N. V. Organon decision is “inconsistent with judicial reasoning, which indicates that it is the active ingredient(s) in the product, rather than the product as a whole which is considered the pharmaceutical substance for the purposes of s 70(2)(a)”.
In summing up his honour concluded that “consistent with judicial reasoning, the claims are directed to a new method of delivery of known active ingredients”. It was therefore held that the extension was correctly refused because the patent claims a new transdermal therapeutic system for administering a known active ingredient and does not disclose a “pharmaceutical substance per se”.
The AAT decision is based on a narrower interpretation of a “pharmaceutical substance per se” than the more generous N. V. Organon and Sanofi-Aventis decisions. This is in direct contrast to the decision at first instance in which both cases were approved and applied by the Deputy Commissioner.
The decision sheds little light on the issue of whether patents claiming drug delivery systems are eligible for an extension of term, and the true effect of the N. V. Organon decision still remains to be seen.