Extension Denied: Gilead Sciences' SPC Application for Combination Anti-Retrovirals
Date of publication: May 1, 2008
By Jonathan Ball and Camilla Sell, DMH Stallard, London
The UK Intellectual Property Office (‘UKIP’) Hearing Officer’s recent decision in case BL O/006/08 (Re Gilead Sciences, Inc. 10 January 2008) has highlighted the difficulty faced by a pharmaceutical patentee seeking a Supplementary Protection Certificate (‘SPC’) for a commercially valuable combination product, relying on its basic composition-of-matter patent.
The basic patent will often have been framed broadly to cover a wide range of compounds, as the patentee did not know which particular product or products would be therapeutically and commercially valuable. This may result in the patent not providing sufficient disclosure of the specific combination to support an application for the SPC.
Introduction
The applicant applied for an SPC, relying on patent EP (UK) 0 915 894, in respect of a product comprising a combination of antiretroviral drugs, tenofovir disoproxil and emtricitabine. The basic patent included a claim to tenofovir disoproxil and its derivatives. Emtricitabine was not expressly disclosed for use in combination with tenofovir disoproxil, although claim 27 of the patent claimed a composition comprising a compound of earlier claims (which included tenofovir disoproxil, ‘together with … optionally other therapeutic ingredients’ (emphasis added).
The examiner refused the application on the basis that the product was not protected by the basic patent as required by the Regulation (see box). This was so even though it was accepted that the combination product may well have infringed claim 27 of the basic patent. The issue that came before the Hearing Officer on appeal was whether the basic patent ‘protects’ the product for which the SPC was applied.
SPCs: an introduction
SPCs, which were introduced by European legislation, may be granted to extend the period of protection under a patent in respect of a specified pharmaceutical (or plant protection) product that is protected by the patent. The intention is to compensate the patentee for at least some of the period of patent term that has expired after patent filing while it undergoes the lengthy process of getting its product authorised and on the market.
The protection granted under an SPC commences on expiry of the basic patent. Its duration is the period equal to the time lost between the date of patent filing and first marketing approval anywhere in the Community,1 minus five years, to a maximum of five years’ extension.2 SPCs (in the present context) are governed by Council Regulation (EEC) 1768/92 (‘the Regulation’). Under Article 3(a) of the Regulation, ‘a certificate shall be granted if, in the Member State in which the application … is submitted … the product is protected by a patent in force’.
‘Product’ is defined in Article 1(b) as ‘the active ingredient or combination of active ingredients of a medicinal product’.
In order to obtain the grant of a certificate, the product to which the application relates must meet the conditions laid down in the Regulation.
The Hearing Officer’s Decision
The Hearing Officer rejected the appeal and the SPC was refused.
Following the decision of the European Court of Justice in Farmitalia,3 it was accepted that it is the patent laws and rules as applied nationally that are relevant to deciding whether a product is protected by a basic patent, provided always that the protection conferred by an SPC cannot exceed the protection conferred by the basic patent.
Accordingly, the relevant English authority of Takeda Chemical Industries Ltd’s SPC Applications (‘Takeda’),4 was applied. Jacob J (as he then was) held in Takeda that although a claim to A may well be infringed by a product of A+B, that did not equate to the combination being ‘protected’ by the patent for purposes of the Regulation. In other words, what might amount to infringement of the patent did not equate to what was ‘protected’ by it.
Rather than an infringement test, the Hearing Officer (as suggested by the applicant) sought to tackle the question by applying the test consistent with the general law on patent construction, namely by reference to what the skilled addressee would have understood at the priority date.
Applying the test, the Hearing Officer took the skilled person as having knowledge in research and clinical practice in treatment of viral infections, and that at the relevant time the use of emtricitabine as an antiretroviral was known, as was the use of different antiretrovirals in combination to treat HIV infection. Given the known use of antiretrovirals in combination, he did not consider that any special significance would have been placed on claim 27 (which claims the further therapeutic agent) by the skilled reader.
The applicant argued that the skilled person would have read into the reference, in the basic patent, the possibility of combining one of the disclosed products with another antiretroviral. Emtricitabine is an example of an antiretroviral well known at the time, and therefore the basic patent should be deemed to protect a combination product of tenofovir disoproxil and emtricitabine.
The Hearing Officer disagreed, finding the applicant’s analysis of the facts too tenuous and reliant on hindsight. In common with many pharmaceutical composition-of-matter patents, the number of products potentially covered was huge. There were a number of possibilities that the skilled reader as of the priority date would have been confronted with, and this was not helped by the fact that there was no teaching whatsoever in the basic patent about what the additional therapeutic agent might be.
Although he accepted that the level of support required might not be as high as that required to support a specific patent claim to the combination product, he would expect to see more than what was in this basic patent, finding that it needs to ‘at least provide a clear pointer for the skilled reader in the right direction.’
The Hearing Officer was not interested in requests from the applicant to take into consideration issues surrounding medicine approvals and the investment required to get new combination products through clinical trials. He considered that this was irrelevant to the question in hand, commenting also that there were other adequate means of protecting such innovation and investment through further patents and the laws on data exclusivity.
Comment
As highlighted by the Hearing Officer, it is in the nature of pharmaceutical composition-of-matter patents to disclose and cover a large range of different chemical entities. They are drafted and filed very often long before the applicant is anywhere near to identifying which particular compound, form or mixture will be therapeutically most useful and commercially valuable. They need to be drafted broadly to give any realistic protection against future infringers.
The decision highlights the inherent difficulty in seeking to use the basic patent to found an application for an SPC in circumstances where the commercial drug is a combination. If the combination is not disclosed in the basic patent sufficiently to be deemed ‘protected’ under the Regulation, no SPC will be given for that product based on that patent. As combination products can be difficult to protect with subsequent patents that have any chance of being held non-obvious, patentees will continue to struggle to obtain extensions to basic patent term for these valuable products.
Originally published in BioScience Law Review, 2008