Paris

The Curie Institute in Paris is to challenge a European patent held by the US biotechnology company Myriad Genetics. The patent covers the BRCA1 gene, used in tests to assess a patient's predisposition to hereditary breast and ovarian cancers.

The French government is officially supporting the institute's action and intends to introduce legislation that would extend compulsory licensing to cover genetic tests.

Utah-based Myriad Genetics, which won a US monopoly on the BRCA1 gene in 1999, obtained a European patent on it in January. As a result, Europeans will be obliged to pay $2,400 for Myriad's screening test — alternative French tests cost less than a third of this.

Worldwide, Myriad has aggressively exercised its exclusive rights to carry out diagnostic testing on BRCA1 and a related gene, BRCA2. It requires that all samples for testing be sent to the company's labs in Salt Lake City.

Estimates vary as to the proportion of breast cancer cases that are hereditary, but the US National Cancer Institute suggests that BRCA1 is responsible for about half of those cases that are genetically inherited.

Myriad's patent, EP 699754, covers all methods for diagnosing the risk of breast cancer based on comparing a sample sequence with the sequence it describes for BRCA1. At a press conference in Paris on 6 September, the Curie Institute said that it will challenge the patent on grounds of lack of novelty and inadequate description.

The institute argues that the patent draws on 'prior art' generated by public genome centres, and also that the sequence used in the initial patent application contained errors, limiting its usefulness. Jacques Warcoin, the Curie Institute's patent adviser, says that other European countries, including Germany, may join the challenge.

Health worries: Dominique Stoppa-Lyonnet says Myriad's test did not identify some expected mutations. Credit: S. LAURE/INSTITUT CURIE

In addition, Dominique Stoppa-Lyonnet, a physician responsible for genetic testing of breast cancer at the Curie Institute, claims that the automated sequencing method used by the Myriad test to identify deletions and mutations detects only 10–20% of the expected mutations.

Stoppa-Lyonnet was co-author of a paper published in June (J. Med. Genet. 38, 388–391; 2001) describing a deletion in the gene accounting for the predisposition of one US family with a history of breast and ovarian cancer. The Myriad test failed to detect any BRCA1 predisposition in the family, the authors said. They detected the new deletion — which, with 12,000 base pairs, accounts for about 15% of the gene — using a technique patented by the Pasteur Institute called combed DNA colour bar coding.

William Hockett, a spokesman for Myriad, says that the company is developing a method to detect such large deletions and that a commercial test will be available by the end of the year.

Opposition to a patent must be filed within nine months of the date the patent was granted, and Warcoin says they will wait until the 9 October deadline before filing to ensure their case is as strong as possible. Hockett says Myriad is unaware of the planned opposition, and would not comment until it had been filed.

The Curie Institute argues in particular that the requirement for samples to be sent to Myriad for testing will deny French scientists data and expertise, and will hamper development of new tests.

The opposition will also challenge the patent's breadth. As it covers all diagnostics based on the gene sequence, it allows Myriad to prevent the marketing of tests developed by the Curie Institute, and others, that use different techniques from Myriad's test.

Roger-Gérard Schwartzenberg, the French research minister, said last week that the government would introduce a bill to extend the laws that govern compulsory licensing to cover diagnostics, and consider exercising this power if Myriad refuses to license its tests to be carried out in France.