THE FATE OF EMBRYONIC STEM CELL PATENTS
By Alexcia Linthicum | April 23, 2014
In 1998, Dr. James A. Thomson isolated human embryonic stem (ES) cells and he assigned a patent for this discovery to the Wisconsin Alumni Research Foundation (WARF) when he was a professor at the University of Wisconsin-Madison. In 2007, Dr. Thomson was the first to derive human induced pluripotent stem cells.
Today, stem cell researchers are developing therapeutic treatments to treat or prevent a variety of diseases or conditions, such as diabetes, retinal diseases and neurodegenerative diseases. There are many companies that specialize in stem cell based technologies. Advanced Cell Technologies and Tengion represent a couple of the top companies in this field.
European Patent for the Isolation of Primate Embryonic Stem Cells
In 1996, WARF filed an application with the European Patent Office (EPO) for the isolation of primate embryonic stem cells. These cells were isolated from rhesus monkeys, but since the patent encompassed primate embryonic stem (ES) cells and humans are primates, the patent covered human ES cells too. The Enlarged Board of Appeals (EBoA) ruled on November 25, 2008, that there was no patent protection for the stem cell application due to reasons of public policy. The EBoA stated that the patent application fell within the exceptions to patentability under Article 53(a)1 and Rule 28(c) EPC2, which prohibits granting patents concerning the “use of human embryos for industrial or commercial purposes.” It is important to note that when the application was filed in 1996 the only way to obtain human ES cells involved the destruction of human embryos.3,4 In addition, the EBoA stressed that their decision wasn’t based on the general question of human stem cell patentability.3,4 In sum, the EBoA’s ruling on this application was based strictly upon the applied patent rules of the European Patent Convention (EPC).4
WARF/Thomson Patents and the USPTO
In 2006, PubPat5 filed formal requests with the USPTO on behalf of Consumer Watchdog6, a non-profit consumer and taxpayer advocate organization, to revoke three WARF patents covering primate embryonic stem cells.7 Consumer Watchdog was interested in Patent Numbers: 5,843,780, 6,200,806 and 7,029,913.7 PubPat submitted previously unseen prior art to show that these patents were not “new” and should be revoked.7 On March 30, 2007, the USPTO rejected all of the claims from each of the patents.7
WARF later amended the claims of each patent by changing the claim language. For example, claim 1 of the ‘780 patent8 originally was the following:
A purified preparation of primate embryonic stem cells which (i) is capable of proliferation in an in vitro culture for over one year, (ii) maintains a karyotype in which all the chromosomes characteristic of the primate species are present and not noticeably altered through prolonged culture, (iii) maintains the potential to differentiate into derivatives of endoderm, mesoderm, and ectoderm tissues throughout the culture, and (iv) will not differentiate when cultured on a fibroblast feeder layer.
The amended claim 1 from the ‘7809 patent states:
A purified preparation of pluripotent primate embryonic stem cells [which] derived from a pre-implantation embryo wherein the stem cells (i) [is capable of proliferation] will proliferate in an in vitro culture for over one year in an undifferentiated state, (ii) [maintains] maintain a karyotype in which all the chromosomes characteristic of the primate species are present and not noticeably altered through prolonged culture, (iii) [maintains] maintain the potential to differentiate into derivatives of endoderm, mesoderm, and ectoderm tissues throughout the culture, and (iv) will not differentiate when cultured on a fibroblast feeder layer.
The USPTO later reissued the ‘780 and ‘806 patents, but not the ‘913.10 The USPTO determined that with the narrowed scope of the amended claims in the ‘780 and ‘806 patents, Thomson’s work was not “obvious” based on the prior art.10
It was initially found that each of the WARF stem cell patents were anticipated and/or obvious based on previous prior art found during the initial re-examination.11 The re-examination of each of these patents could have been avoided if a thorough prior art search was conducted. It seems that the company that conducted the search considered some prior art, not the best prior art. In conclusion, if the best prior art had been found, either by Consumer Watchdog, PubPat or the initial patent analyst, and a thorough search was conducted, a definitive decision on these patents would have been made without subsequent recourse.
In 2013, Consumer Watchdog appealed the USPTO’s decision to the US Court of Appeals for the Federal Circuit Court.7 Consumer Watchdog believes that the US Supreme Court ruling on human genes should apply to stem cells.12 However, the USPTO believes there should be no appeal because the patent is valid and “except at the behest of a party with a concrete and particularized interest in the question presented, neither this Court nor any other Article III tribunal has the power to render judgment.”13
If the consumer advocate group, Consumer Watchdog, is denied an appeal with the Federal Circuit Court this case could be seen before the US Supreme Court.14 In the 2013 Myriad Genetics case, the Supreme Court’s decision was that products of nature are not patent eligible.15 Justice Thomas stated “genes and the information they encode are not patent eligible simply because they have been isolated from the surrounding genetic material.”16 Consumer Watchdog could easily argue that WARF did not create human ES cells, thus they should not have intellectual property rights to them. Further, based on the Supreme Court’s decision on human genes, it could be argued that the isolation of human embryonic stem cells from the blastocyst is not patent eligible, much like the isolation of human genes from DNA was determined to be not patent eligible.
It will be interesting to see how the case of WARF v. Consumer Watchdog concludes. The court’s decision will provide the public with a definitive answer as to whether or not the isolation of embryonic stem cells is patentable in the United States. In conclusion, this is a landmark case that will determine the patentable future of this area of biotechnology in the United States.
1 Article 53(a): European patents shall not be granted in respect of: inventions the commercial exploitation of which would be contrary to "ordre public" or morality; such exploitation shall not be deemed to be so contrary merely because it is prohibited by law or regulation in some or all of the Contracting States. The European Patent Convention, http://www.epo.org/law-practice/legal-texts/html/epc/2013/e/ar53.html
2 Rule 28(c): European patents shall not be granted in respect of biotechnological inventions which, in particular, concern the following: uses of human embryos for industrial or commercial purposes. The European Patent Convention, http://www.epo.org/law-practice/legal-texts/html/epc/2013/e/r28.html
3 Patents on Biotechnology, www.epo.org
4 European Legal Update: Enlarged Board of Appeal at the European Patent Office Rejects the WARF/Thomson Stem Cell Patent Application Appeal http://www.edwardswildman.com/insights/PublicationDetail.aspx?publication=1543
5 PubPat: non-profit organization that limits the abuse of the US patent system and works to petition the USPTO to review patents suspected of being invalid; the founder of this organization is Dan Ravicher.
6 Consumer Watchdog: non-profit consumer advocate organization, formerly the Foundation for Taxpayer and Consumer Rights, headquartered in Santa Monica, California.
7 WARF Stem Cell Patents, http://www.pubpat.org/warfstemcell.htm
8 US 5,843,780 A (THOMSON, J.A.) December 1, 1998
9 Ex Parte Reexamination Certificate, US 5,843,780 C1 (THOMSON, J.A.) June 17, 2008
10 Patent office upholds remaining WARF stem cell patents, http://wtnnews.com/articles/4601/
11 Patent office Order Rejecting Patents, Office Action in Ex Parte Reexamination http://www.pubpat.org/warfstemcell.htm
12 Consumer Watchdog Argues That WARF Stem Cell Patent Is Invalid Under §101
13 U.S. PTO: Consumer Group Lack Standing To Appeal Stem Cell Patent, http://www.consumerwatchdog.org/story/us-pto-consumer-group-lacks-standing-appeal-stem-cell-patent
14 Power Grab?: USPTO Says No Appeal (CW v. WARF Part V), http://patentlyo.com/patent/2014/01/power-uspto-appeal.html
15 U.S. Supreme Court Strikes Down Human Gene Patents, http://news.sciencemag.org/people-events/2013/06/u.s.-supreme-court-strikes-down-human-gene-patents
16 Wolf, Richard. Justices rule human genes cannot be patented. http://www.usatoday.com/story/news/nation/2013/06/13/supreme-court-gene-breast-ovarian-cancer-patent/2382053/