The ethics of patenting inventions relating to human embryonic stem cells (hESCs) has been the subject of much debate. Inventions which are contrary to morality are excluded from patentability under the European Patent Convention and the law explicitly sets out that this exclusion encompasses uses of human embryos for industrial or commercial purposes(1). Over the past decade, several high-profile cases have shaped the law in this regard, but the scope of this exclusion remains uncertain due to the decisions raising new questions (2-4). A Technical Board of Appeal of the EPO has now issued decision T2221/10, which signals that the EPO is adopting a broad interpretation of the exclusion from patentability on moral grounds. However, the practice is likely to continue to develop.
The patentability of biotechnological inventions in the European Union (EU) is governed by the “Biotech Directive”, which has been implemented into national law by EU member states and adopted by the European Patent Office (EPO)(5). According to the Biotech Directive, inventions are not patentable where their commercial exploitation would be contrary to public order or morality, and the use of human embryos for commercial or industrial purposes is explicitly prohibited. However, the absence in the Biotech Directive of a definition of the term "human embryo" and the lack of an explanation as to what acts constitute the "use of a human embryo" have created uncertainty surrounding the patentability of inventions relating to hESCs.
In 2008, in a landmark case known as the “WARF” decision, the Enlarged Board of Appeal, the highest authority of the EPO, held that inventions which necessarily require the destruction of a human embryo are not patentable(2). European patents could, however, be obtained for inventions which from the filing date of the patent could be worked using an existing hESC line. hESC lines are cultures of hESCs that can be maintained and propagated in a laboratory to provide an essentially unlimited supply of hESCs. As discussed below, historically hESC lines were originally established by destroying an embryo. The EPO was satisfied that hESC lines were publicly available from 9 May 2003, so it was possible to obtain patents relating to HESCs providing that the filing date was after 9 May 2003.
By contrast, in 2011, in response to questions referred to it by the German Federal Supreme Court (Bundesgerichtshof), the Court of Justice of the EU (CJEU) signalled a significant change to European patent practice when it held that it is immaterial how far removed the destruction of a human embryo is from the invention(3). According to the CJEU, the exclusion applies not only to those inventions which directly involve the destruction of an embryo, but also to those requiring the use of a hESC that was originally derived through the destruction of a human embryo. Thus, the CJEU considers that excluded from patentability are any methods or products that involve as their base material cells taken from an existing hESC line which was originally obtained through the destruction of a human embryo, no matter how long ago the hESC line was originally established.
The EPO amended its Guidelines for Examination to implement the ruling of the CJEU, even though it – unlike EU member states – is not bound by decisions of the CJEU. The legitimacy of this approach has been questioned by many applicants.
Refusal of European hESC patent application
A technical Appeal Board of the EPO recently had to decide whether, and if so, how, the CJEU’s ruling impacts on EPO practice. Appeal T2221/10 was filed by Technion Research & Development Foundation Ltd. (Technion) against the refusal of its patent application directed to methods of culturing hESCs.
Technion argued that the claimed invention could be put into practice by using pre-existing hESC lines. They filed evidence purporting to show the public availability of suitable hESC lines before the priority date of the patent application. Their position was that given that the invention could be put into practice by resorting to such cell lines, no destruction of a human embryo was required. The EPO’s provisions on morality were therefore not contravened.
The Appeal Board rejected these arguments, adopting the view expressed by the CJEU that it would be wrong only to look at the steps recited in a claim. Instead, it is necessary also to consider all of the steps that are a necessary precondition for carrying out the claimed invention. It is therefore not sufficient to determine that an invention may be carried out without any de novo destruction of a human embryo to obtain hESCs because an existing hESC line may be used. A determination must also be made as to whether the existing hESC line was originally produced by destroying a human embryo.
The fundamental question is thus not whether any hECS lines were publicly available at the priority or filing date of the application, but whether at least one hECS line was publicly available which had been generated without destroying a human embryo. According to the Appeal Board, there was no evidence that any of the hESC lines that were alleged to have been publicly available at the filing date of the patent had been obtained without destroying a human embryo. The Appeal Board therefore concluded that the claimed invention could at its filing date not be practiced without contravening the morality provisions.
The Appeal Board also took the opportunity to discuss the influence of rulings of the CJEU on the EPO. It acknowledged that the judgements of the CJEU are not legally binding on the EPO and its Appeal Boards, but also emphasised the need for harmonisation of patent law in Europe. It concluded that, given that the national courts of EU member states are bound by the decisions of the CJEU, the EPO should take decisions of the CJEU into consideration.
Impact and outlook
According to this decision, the EPO's morality provisions are contravened if an invention could at its filing date only be put into practice by using hESCs that were originally obtained through the destruction of a human embryo. The EPO has previously indicated that the first method for producing hES cell lines without destroying a human embryo published in February 20086. Patent applications relating to hESCs which were filed pre-February 2008 are therefore now more likely than ever to be rejected for contravening the EPO's morality provisions. Such patent applications should be reviewed carefully to try to identify patentable subject matter. In some instances it may be possible to pursue claims directed to compositions or apparatus suitable for stem cell methods, provided, of course, that the application as filed provides a sufficient disclosure in this regard. A limitation to "non-human" embryonic stem cells could also be made, although in many cases this is unlikely to be of value to the applicant.
The outlook for patent applications having a filing date after February 2008 is much better, because the EPO seems to be satisfied that after this date it was possible to put into practice inventions relating to hESCs without destroying a human embryo. Indeed, we have in connection with such applications seen some Examination Reports that have explicitly acknowledged that the morality provisions are not contravened. However, it should be borne in mind that this is a practice that seems to have evolved at the EPO without –as yet - having been confirmed by an Appeal Board.
However, it is unlikely that T2221/10 will be the final word on this issue. T1808/13, an appeal filed against the revocation of the well-known “Brüstle” patent directed to neural precursor cells derived from hESCs, is currently pending before the EPO’s Appeal Board. Whilst there is a good chance that this appeal will merely confirm the principles set out in T2221/10, it is hoped that eventually an Appeal Board will ask the Enlarged Board of Appeal to provide more definitive guidance on the scope of the exclusion from patentability of inventions relating to human embryonic stem cells.
Meanwhile, it is also worth noting that referral C-364/13 to the CJEU is currently pending, seeking clarification on the patentability of parthenotes which, unlike fertilised ova, contain only pluripotent cells and are incapable of developing into human beings(7).
A key issue in case C-364/13 is the question of whether the ability to develop into a human being is a defining feature of an embryo. If the CJEU accepts the argument that the use of parthenotes does not constitute the use of a human embryo because parthenotes cannot develop into a human being, then there might be fresh hope for hESC applications filed before 2008. This is because methods of obtaining hESCs from embryos which have arrested development and can therefore not develop into a human being were known at least as early as September 2006(8).
In conclusion, although the EPO’s Appeal Board has tried to send a clear message regarding the patentability of hESCs in Europe, the scope of the exclusion remains uncertain and we could still be a long way off a definitive answer.
First published in IP Magazine, July/August 2014