(1) Sandoz Limited, (2) Hexal AG v (1) G.D. Searle LLC, (2) Janssen Sciences Ireland UC
This decision from the UK Court of Appeal concerns Article 3(a) of the supplementary protection certificate for medicinal products (“the SPC Regulation”). The SPC Regulation enables the proprietor of a patent for a medicinal product to obtain an SPC which extends the duration of the patent with respect to that product so as to compensate the proprietor for the effective loss of patent term caused by the need to obtain a marketing authorisation before the product can be marketed.
The appeal concerned the meaning of “the product is protected by a basic patent in force” in Article 3(a) of Regulation (EC) No 469/2009 concerning the SPC Regulation.
The first respondent (“Searle”) is the proprietor and the second respondent (“JSI”) the exclusive licensee) of SPC/GB07/038 (“the SPC”) for a product described in the SPC as “darunavir or the pharmaceutically acceptable salt, ester, or prodrug thereof”.
The SPC covered a product which is marketed in Europe by companies related to JSI under the trademark Prezista. Prezista is a protease inhibitor and is an anti-retroviral medication used in the treatment of human immunodeficiency virus (HIV) and AIDS. The SPC was based on EP (UK) 0 810 209 (“the Patent”). The claims of the Patent defined a class of compounds by reference to a Markush formula. Darunavir is a specific compound that falls within the scope of this formula. It is common ground that there is no reference to darunavir in the Patent.
The appellants sought to revoke the SPC, which expires on 23 February 2019, in order to clear the way for the marketing of their generic darunavir product. They argued that the
SPC was invalid because, on the true construction of Article 3(a) of the SPC Regulation, darunavir is not a product “protected” by the patent. Article 3(a) of the SPC Regulation specifies that a SPC can only be granted if the product is protected by a basic patent in force. The Appellants admitted for the purposes of these proceedings only that, if the SPC was valid, then the marketing of their product prior to expiry of the SPC would infringe it.
At first instance, Arnold J declined to refer questions to the CJEU on the interpretation of Article 3(a) of the SPC Regulation because he considered that, on all tenable constructions of Article 3(a), darunavir was protected by the patent.
The appellants’ argument was that for product to be protected by a basic patent for the purposes of Article 3(a) of the SPC Regulation, it must be shown that “the skilled team would recognise the product as forming a part of the subject matter of the patent by reference to a careful reading of the patent based on the common general knowledge at the priority date”. Their evidence was that a particular substituent in darunavir was unusual, and that, given the large number of compounds covered by the claim, the “common general knowledge test” was satisfied.
The respondents’ counterargument was that darunavir would be protected by the patent if it were one of the class of products defined and claimed in the claims of the patent by reference to the Markush formulae.
The judge, Floyd LJ summarised the relevant case law of the CJEU and pending references, with particular focus on Medeva (MeC-322/10 Medeva BV v Comptroller-General of Patents, Designs and Trade Marks  ECR I-12051) and Eli Lilly (C-493/12 Eli Lilly & Co Ltd v Human Genome Sciences Inc.).
He first considered the CJEU’s requirement, formulated for the first time in Eli Lilly, that, in order to be protected by the basic patent, the claim must relate to the product implicitly, but necessarily and specifically (“the Lilly requirement”). He questioned whether the Lilly requirement was limited to functional claims, or alternatively, if it applied to all claims, was it always satisfied by a Markush claim which covered the active ingredient?
Floyd LJ noted that the time at which and the circumstances in which the national authority had to determine whether a product was protected by a basic patent was important. He agreed with the respondents’ submission that this should be judged when the product was known, and when it had been authorised to be placed on the market as a medicinal product, but noted that this conclusion still left the question of what was the necessary exercise for determining whether the product was protected by the patent. Is it (a) to ask whether it was clear that the product was claimed as such; or (b) to ask whether the product is one which was sufficiently identified?
Floyd LJ acknowledged that the “Lilly requirement” stems from the CJEU’s decision in Medeva that all members of a combination of active ingredients which was the subject of a SPC must be specified in the wording of the claims. However, he noted that the reasoning in Medeva was not informative as to how specifically the claims must focus on the active ingredient, or what underlay the requirement that they should do so. On this basis, he concluded that Medeva left a substantial unanswered question as to whether a product could be specified by a functional claim at all.
For guidance as to what underlies the “specificity requirement”, Floyd LJ referred to the CJEU’s reasoning at paragraph  of the Eli Lilly judgement. In his view, this paragraph indicated that the court considered that insisting on a high degree of specificity in the basic patent was one way of hindering the marketing authorisation of third parties from being used as the basis for SPCs. He suggested that this might be helpful in preventing a patentee from spreading the net in his patent claims widely and unspecifically to obtain an extended term which he had not earned. He stated that this consideration did not only arise in the context of functional claims, and provided supports for the suggestion that there was a general requirement that the active ingredient which was the subject of the SPC must be identified.
Floyd LJ agreed with the respondents’ argument that there was a “spectrum of specificity” indicated by the factual scenarios in the various decided cases and references. He accepted that a Markush claim could in some circumstances be a sufficiently precise claim for the purposes of Article 3(a), but also acknowledged that an active ingredient could not necessarily be adequately identified by a Markush formula however broadly that formula is framed and however obscure the particular substituent required to form the active ingredient that was the subject of the SPC.
On considering the “common general knowledge test” proposed by the appellants, Floyd LJ referred to Eli Lily and also the German Sitagliptin reference (Decision 14 W (pat) 12/17). He recognised that there were some undesirable consequences with the common general knowledge test but rejected the respondents’ argument that the common general knowledge test was essentially a breadth of claim test, concluding that it was simply a test of whether the claim met the requirement that the active ingredient be identified specifically.
Floyd LJ also expressed his concerns in relation to the “identification test”. Referring to Sitagliptin and Teva UK v Gilead Sciences Inc  EWHC 13 (Pat), he agreed with the first instance judge that a far better test would be to ask whether the product which was the subject of the SPC embodied the “core inventive advance” of the basic patent. He noted that if that test were applied to this case, he had no doubt that the SPC would satisfy Article 3(a).
In order to assist the Court of Justice, Floyd LJ expressed his provisional conclusions:
“Left to myself, I would have concluded that darunavir was a product protected by the claims of the patent. In the case of a product with a single active ingredient and a patent with a claim which identifies a number of compounds by means of a Markush formula, all of which compounds embody the core inventive technical advance of the patent, the test should be whether the skilled person, considering the claims of the patent on the one hand and the structure of the product in question on the other, would immediately recognise that the active ingredient in question is one of those specified by the formula. On the facts of the present case as found by the judge, that test is satisfied. However, for the reasons I have given, it is not clear that this is the correct approach in EU law.”
With the agreement of Kitchin LJ and Lewison LJ, Floyd LJ stayed the appeal proceedings and referred the following question to the CJEU:
“Where the sole active ingredient the subject of a supplementary protection certificate issued under [the SPC Regulation] is a member of a class of compounds which fall within a Markush definition in a claim of the patent, all of which class members embody the core inventive technical advance of the patent, is it sufficient for the purposes of Article 3(a) of the SPC Regulation that the compound would, upon examination of its structure, immediately be recognised as one which falls within the class (and therefore would be protected by the patent as a matter of national patent law) or must the specific substituents necessary to form the active ingredient be amongst those which the skilled person could derive, based on their common general knowledge, from a reading of the patent claims?”
There are now three pending referrals to the CJEU regarding the interpretation of Article 3(a), following referrals from the UK High Court in Teva v Gilead  EWHC 13 (Pat) and from the German Federal Patent Court in the Sitagliptin case (14 W (pat) 12/17).