It’s no news that the European Patent Convention (EPC) does not allow European Patents to be granted in respect of biotechnological inventions concerning the industrial or commercial use of human embryos. Indeed, in a landmark decision of the Enlarged Board of Appeal (EBoA) of the European Patent Office (EPO), it was decided that a European Patent cannot be granted for an invention, which necessarily involves the use and destruction of human embryos.

In a recent decision, a Technical Board of Appeal of the EPO has confirmed that European Patents will not be granted in view of the established legal prohibition relating to inventions contrary to “ordre public” or morality, in particular inventions concerning uses of human embryos. The European Application in question related to a method of maintaining human embryonic stem (hES) cells in an undifferentiated state, and a cell culture comprising hES cells. The European Application was refused on the basis that the only possibility to implement the claimed method involved destroying human embryos, because the claimed hES cells were not publicly available before the priority date.

Despite the appellant arguing that the claims did not explicitly specify a step of obtaining hES cells by destruction of human embryos, the Technical BoA were of the opinion that the use of the disclosed (publicly available) hES cell lines would nevertheless be in conflict with the EPC, because those hES cell lines had originally been produced by a method involving the destruction of a human embryo, and all steps preceding the claimed use of hES cells have to be considered when assessing patenability.

Taken together, the Technical BoA concluded that the claimed invention depends entirely on the use of hES cells, either obtained by de novo destruction of human embryos or by using established hES cell lines, which were initially obtained by methods involving the destruction of human embryos, both of which preclude patentability under the EPC.

So, can Applicants rely on national patent law to patent stem cells in Europe? The morality exclusion specifically provided for in the EPC finds basis in the EU Biotech Directive, which harmonises the patent laws of EU Member States regarding the patentability of biotechnological inventions – meaning that Applicants could face the same legal prohibition in each EU Member State. Certainly, the decision of the Technical BoA is in line with a judgement given by the Court of Justice of the European Union (CJEU) with regard to the exclusion from patentability of an invention requiring the prior destruction of human embryos.

Even though the EPO and the CJEU appear to have taken an agreeing stance on the matter, the EPO appears to exclude any invention necessarily involving the use and destruction of human embryos; whereas the CJEU looks to have defined certain cell types capable of commencing the process of development of a human being, which are to be excluded – suggesting that pluripotent cell types, which can differentiate into nearly all cells but cannot construct a complete, viable organism, might be patentable outside the EPC.

In this connection, certain Member States have shown a willingness to allow the grant of patents concerning certain stem cell types. The UK Patents Court, for example, has taken the preliminary view that, although totipotent cells should be excluded from patentability, pluripotent cells should not; and has referred to the CJEU the question of whether unfertilised human eggs containing only pluripotent cells incapable of developing into human beings are to be considered “human embryos”. Applicants might find that relying on the national patent route and directing an Application to pluripotent stem cells could be a means of escaping the European restriction on the patentability of certain stem cell types.

In any event, the case before the Technical BoA of the EPO hinged on the public availablility of the hES cell lines, and was dismissed because it could not be proven that, at the claimed prioirty date, hES cells that were produced without destruction of human embryos were publicly available. However, the advance of technology might allow Applicants to now lay claim to hES cells, in light of the discovery that mature cells can be reprogrammed to become induced pluripotent stem (iPS) cells, meaning that human embryos are not required to produce the stem cells. Applicants who can exemplify the utility of an invention based on iPS cells might well find some latitude with regard to patentability before the EPO and across the EU.

Assuming the technical basis of an invention allows, and until we have clarity from both the EPO and the CJEU, Applicants should ensure that at least one example of either exclusively pluripotent cells, non-human ES cells, or iPS cells is included in a patent application.