In October 2011, we reported on the decision by the Court of Justice of the European Union (CJEU) in Oliver Brüstle v Greenpeace eV [2012] 1 CMLR 41, which found that a patent should not be granted to an invention if its implementation requires the prior destruction of human embryos or their prior use as base material, a ruling that was also likely to extend to inventions that require the use of immortalised human embryonic stem cell (ESC) lines.

The ruling of the CJEU in Brüstle concerned the interpretation of provisions under European patent law (Article 6(2)(c) of Directive 98/44/EC), which exclude from patentability "uses of human embryos for industrial or commercial purposes." The CJEU held that a "human embryo" includes (i) a fertilised human ovum, (ii) a non-fertilised human ovum that has had its nucleus replaced with a nucleus from a mature cell and (iii) a non-fertilised human ovum whose division and further development has been stimulated by parthenogenesis. The CJEU reached its finding in view of the scientific evidence before it, which demonstrated that these cell types were "capable of commencing the process of development of a human being".

Following a recent decision handed down by the UK Patents Court in April 2013 (International Stem Cell Corporation v Comptroller general of Patents [2013] EWHC 807), the CJEU is being asked to clarify whether the exclusion to patentability under Article 6(2)(c) extends to parthenotes or, more specifically, to pluripotent human ESCs that do not have the capacity of developing into a human being.

UK Patent Office refuses patent applications to parthenogenetically-derived human embryonic stem cells

In 2012, the UK Intellectual Property Office refused two applications by International Stem Cell Corporation (ISCC) on the basis that the claimed invention contravened Article 6(2)(c) of Directive 98/44/EC as encompassing "uses of human embryos for industrial and commercial purposes". The applications in question claimed methods of producing pluripotent human ESC lines from parthenogenetically-activated oocytes (GB0621068.6) and methods of isolating pluripotent human ESC lines from parthenogenetically-activated oocytes (GB0621069.4). In those proceedings, ISCC presented scientific evidence demonstrating that parthenogenetically-activated ESC are pluripotent and therefore incapable of developing into human beings. This is to be contrasted with fertilised human ova or non-fertilised human ova that have had their nucleus replaced with a nucleus from a mature cell, which give rise to totipotent ESCs that are capable of developing into human beings.

The Comptroller agreed that, on the evidence before it, parthenogenetically-activated pluripotent ESCs are not capable of developing into human beings. However, it was not entirely clear to the Comptroller whether the CJEU intended to exclude from patentability human ESCs that do not have the capacity to develop into a human being. Therefore, applying a broader meaning to the CJEU's decision in Brüstle, both applications were ultimately refused.

On appeal, UK Court unclear as to whether earlier CJEU decision should extend to parthenotes

International Stem Cell Corporation (ISCC) lodged an appeal to the High Court of Justice, Chancery Division, UK Patents Court, which was heard by Justice Henry Carr QC. His Honour agreed with ISCC that, on the new evidence before him, parthenogenetically-activated pluripotent human ESCs should not be excluded from patentability, as they are incapable of developing into human beings. In his view, to exclude processes of development which are incapable of leading to a human being does not strike a balance between the objective of Article 6(2)(c) of Directive 98/44/EC to encourage research in the field of biotechnology by means of the patent system and the need to respect the fundamental principles safeguarding the dignity and integrity of a human embryo.

However, his Honour also agreed with the Comptroller that there is "insufficient clarity as to what the CJEU did mean in Brüstle" and that it was also unclear whether the CJEU would have reached the same conclusion if it was presented with this new evidence, which was different to that before the CJEU in Brüstle. Therefore, his Honour said that it was appropriate to seek further clarification from the CJEU on this issue.

CJEU to clarify whether parthenogenetically-derived human embryonic stem cells are excluded from patentability

The following question has since been referred to the CJEU:

Are unfertilised human ova whose division and further development have been stimulated by parthenogenesis, and which, in contrast to fertilised ova, contain only pluripotent cells and are incapable of developing into human beings, included in the term “human embryos” in Article 6(2)(c) of Directive 98/44/EC on the legal protection of biotechnological inventions?.

A decision by the CJEU is likely to issue in the new year, which should clarify the European position on the patentability of parthenogenetically-activated pluripotent human ESC.

Impact on human embryo-derived inventions

We will have to wait to see how the CJEU decides on the question before it. In view of the new evidence presented by ISCC, we are hopeful that the CJEU will follow the same reasoning adopted by the Comptroller and the UK High Court and, in doing so, find that parthenogenetically-activated pluripotent human ESCs should not be excluded from patentability under Article 6(2)(c) of Directive 98/44/EC as they are incapable of developing into human beings.

In the meantime, those wishing to pursue a European patent for an invention that involves the use of stem cells should ensure that their patent specification includes at least one example of the use of stem cells other than human ESCs.