paris

Researchers last week won their challenge to a European patent on the use of stored stem cells from umbilical-cord blood, a technology with promising applications in bone marrow transplants and gene therapy. The patent was granted three years ago to the US company Biocyte.

Cord blood stem cells can produce red and white blood cells and platelets, and their transplantation is more effective and cheaper than the conventional practice of taking stem cells from bone marrow donors. Their lower immunogenicity, for example, reduces the risk of rejection by the patient.

But the potential threat of expensive litigation over claims of patent infringement has deterred companies and research groups from exploring new uses for cord blood cells, according to Eliane Gluckmann, a researcher at the Hôpital St Louis in Paris. “That threat has now been lifted,” she says.

Gluckmann chairs Eurocord, the European Cord Blood Bank, which involves 14 research teams. It has led the challenge to the patent, along with several other organizations including the environmental group Greenpeace, the US biotechnology company Thermogenesis, and Astra Pharmaceuticals (see Nature 382, 99; 99 1996).

The patent covered “hematopoietic stem and progenitor cells of neonatal and fetal blood, that are cryopreserved, and the therapeutic uses of such cells upon thawing,” and gave the company broad rights. The groups had opposed it on ethical grounds, arguing that it was wrong to patent human tissues. But they fought the legal battle on the basis of classical patent law, claiming that the technology described in the patent was not new.

Last week, the European Patent Office in Munich upheld their claim. According to an official, the patent “lacked novelty or an inventive step”. The patent office was convinced by several papers describing similar techniques that predated the patent. The official adds that a key element was testimony by Pablo Rubenstein, a researcher at the New York Blood Center, that he had used the techniques long before the patent was applied for.

Rubenstein describes the result as a victory for proper attribution of innovation. He argues that, although the patent was defeated on legal grounds, it is also an ethical victory, as it overturns a patent on human tissues.

Neither Biocyte, which is free to appeal, nor its lawyers were available this week for comment. The patent has already been rejected in the United States and Japan.