Supplementary protection certificates (SPCs) can extend market exclusivity for a pharmaceutical product after basic patent expiry by up to five years. In order for a pharmaceutical product to be entitled to further protection by a SPC extending the duration of a basic patent, however, European Union law requires, amongst other things, that the product must be ʽprotected by a basic patent in forceʼ. This might seem a simple matter, but it has been the subject of a number of rulings by the Court of Justice of the European Union (CJEU) in recent years that have been anything but simple.

The earlier decisions of the CJEU began by precluding SPC protection where it relates to active ingredients which are ‘not specified in the wording of the claims in that basic patent’. Further cases have attempted to elaborate on the degree of specificity that this requires: does it include functional definitions and generic structural definitions, or must products be named individually and expressly by the patent claim? The rulings in these cases have tended to confuse the issue rather than clarify it.

The latest case in which this issue has arisen in the CJEU is Teva UK Ltd & Others v Gilead Sciences Inc (Case C‑121/17 – the ‘Truvada Case’), which was referred to the CJEU for a preliminary ruling by the Patents Court of England & Wales. The case concerns an SPC protecting Gilead's HIV treatment, Truvada. Truvada consists of a combination of tenofovir disoproxil and emtricitabine in a fixed dose tablet. The validity of the SPC was challenged on the basis that the relevant claim of the basic patent does not expressly identify the emtricitabine ingredient, but merely claims the optional combination of tenofovir disoproxil with ʽother therapeutic ingredientsʼ.

In the absence of clear criteria in the earlier CJEU decisions the English Patents Court requested a preliminary ruling from the CJEU on the following question: What are the criteria for deciding whether “the product is protected by a basic patent in force” in Article 3(a) of the SPC Regulation?

In response, the CJEU has ruled that if the ingredient is not expressly mentioned, such as emtricitabine in this case, then in order to be "protected" the 'person skilled in the art' in question – a legal fiction in patent law – must understand on the basis of the 'prior art' at the date of the basic patent and all the information disclosed by that patent, that the ingredient is nonetheless identified necessarily and specifically by the patent claim. In particular, given the overall context and information in the patent, the skilled person must understand that the combination of ingredients must necessarily fall under the invention of the patent and that each of the active ingredients is disclosed by the patent.

The CJEU states that it would be contrary to the objective of the SPC Regulation for a SPC to provide protection which goes beyond the invention covered by the basic patent. The SPC Regulation expressly requires account to be taken of all of the interests at stake. It is evident that in proposing the test it does, the CJEU has this balance in mind.

The ruling in the Truvada Case therefore goes some way to providing guidance on how to determine when a product is protected by a patent for the purpose of SPC protection in relation to combination products. However, the CJEU rules on the law and does not come to a final decision on the facts. Instead, it is a matter for the referring national court to apply the ruling to the facts before it.

In the Truvada Case, the CJEU has nonetheless expressed its own view that it ʽdoes not seem possibleʼ that a person skilled in the art would be able to understand that the combination of emtricitabine with tenofovir disoproxil is necessarily and specifically identifiable as falling under the invention covered by the patent claims. The Patents Court must now determine what in fact the skilled person would have taken from the basic patent as necessarily and specifically identifiable on the basis of the evidence before it and decide whether the SPC is not valid and must be revoked. The decision of the Patents Court will, however, only impact the UK SPC. Indeed, in some countries, such as Germany, the Truvada SPC has already been declared invalid.

Although the decision of the Patents Court is still awaited, if it takes the same view as the CJEU on the facts invalidation and revocation of the SPC would open up the UK market to potential competition from generic versions of Truvada.

The CJEU decision in the Truvada Case is unlikely to be the end of the issue in future cases, even in relation to combination products. Instead, disputes are likely to shift to the question of what exactly the person skilled in the art would take from the basic patent to be necessarily and specifically identifiable on the basis of the prior art at the date of the patent. There is also the possibility that there will be referrals to the CJEU raising further questions of clarification. There are also questions in relation to other types of claims, such as Markush formulae and functional claims, which are not addressed by this ruling. Indeed, there are already two other references pending before the CJEU concerning similar issues in respect of other forms of patent claim. As previous rulings have demonstrated, these may or may not provide more clarity.

Matthew Royle is a partner and Paul England the senior professional support lawyer in the Life Sciences Sector group at Taylor Wessing