Scientists are still grumbling about the Wisconsin Alumni Research Foundation’s grip on stem cell patents–a hold strengthened by rulings this and last month affirming WARF’s patents on primate and human embryonic stem (ES) cells. But there is a widespread feeling that challenges to WARF’s patents and continuing public pressure have had a desirable effect. "I think [WARF has] been moving toward what I would consider to be a more reasonable policy" with regard to giving scientists access to the cells, says bioethicist LeRoy Walters of Georgetown University in Washington, D.C.
WARF, affiliated with the University of Wisconsin, Madison, holds three patents arising from work done in the 1990s by Wisconsin researcher James Thomson. On 25 February, the U.S. Patent and Trademark Office (PTO) upheld a 2006 patent that describes a method for cultivating pluripotent cells. Then on 10 March, it upheld patents, granted in 1998 and 2001, on nonhuman primate and human ES cells, which apply to all such cells regardless of how they are derived.
Two citizens’ groups first challenged WARF’s patents in October 2006, claiming that the method for deriving the cells was "obvious" and could have been successfully applied by anyone equipped with the necessary resources. Last April, PTO agreed to reexamine them (Science, 13 April 2007, p. 182). In its final decision, PTO rejected the challengers’ arguments, saying that "[I]n view of the unpredictability" associated with both the isolation and long-term sustainability of primate ES cells, "the present claims are not obvious. …"
WARF Managing Director Carl Gulbrandsen, who had predicted a "tough fight," proclaimed WARF to be "heartened that … the patent office reached the correct conclusion."
During the course of the patent examination, WARF eased up on proprietary claims: It no longer demands licensing fees from companies that do university-based research with its cells; and it narrowed its claims to apply only to ES cells derived from fertilized embryos and not pluripotent cells from other sources, such as clones or the newly developed induced pluripotent stem (iPS) cells. These actions mean that despite the PTO ruling, "we think we’ve already won a major victory with these patent challenges," says John Simpson of the Foundation for Taxpayer and Consumer Rights in Santa Monica, California, the "requestor" in the dispute.
Nonetheless, the groups plan to appeal the decision on the one patent that can be appealed under PTO rules. "Frankly, I don’t trust them to behave well unless we keep up the pressure," says stem cell researcher Jeanne Loring of the Scripps Research Institute in San Diego, California, who supports the patent challenge.
Harvard University stem cell researcher Chad Cowan agrees with others that the case has "caused WARF to finally wake up to the fact that they needed to be a lot more engaging with academic scientists." But Cowan still thinks the patents are a drag on the field. The recent early successes with iPS cells, which can be grown without the use of eggs or embryos (Science, 1 February, p. 560), will only intensify the interest in ES research, he says. ES cells are still needed to validate iPS cells, and even if iPS cells prove viable substitutes for ES cells in research, some scientists believe they will never be suitable for cell therapy.
Alan Trounson, president of the California Institute for Regenerative Medicine in San Francisco, says his biggest concern is down the road, because "the patents could delay developments" of therapies with ES cells. He says it would be bad for everyone if a biotech company got a monopoly on certain therapies.
Meanwhile, as iPS patent applications flood into PTO, future patent issues will no doubt become even more complicated.