BioWorld International Correspondent

PARIS - ExonHit Therapeutics SA and BioMérieux extended and expanded their research collaboration for developing new blood-based diagnostics for the early detection of cancers.

The original agreement was formed in 2001 and renewed in 2003; it focused on a breast cancer diagnostic. Now, the collaboration has been extended for six years and expanded to include a variety of other cancers for which a blood tissue diagnostic is needed, including colon, prostate and lung. The companies are committed to conducting research programs in at least five cancers.

Their specific objective is to develop DNA microarrays for detecting genetic cancer markers in the blood or in tumor samples. Their collaboration draws on ExonHit's knowledge and technology in the field of gene expression and its ability to identify "spliced signatures" associated with tumors, and on BioMérieux's expertise in the development and commercialization of diagnostic tests.

Specifically, ExonHit applies its DATAS (differential analysis of transcripts with alternative splicing) technology to BioMérieux's clinical collections of biopsies and blood samples taken from cancer patients in order to define genetic signatures that are then compiled on ExonHit's Proof-Hit macroarrays. The signatures enable the presence of a specific cancer in the tissue to be characterized and the patient's individual response to a given treatment to be determined in advance.

ExonHit Therapeutics' CEO, Bruno Tocqué, said the collaboration should yield a "breakthrough" in the diagnosis of cancer. He told BioWorld International that "from a single drop of blood, it will be possible to detect the early signs of several types of cancer."

The agreement provides for Paris-based ExonHit to grant BioMérieux, of Marcy l'Etoile, France, an exclusive license for the use of its technology in blood diagnostics, gene profiling and the microarray design. In exchange, BioMérieux will fund ExonHit's R&D, as well as pay milestones for development goals and royalties on future product sales.

Financial details were not disclosed, and Tocqué, declined to disclose the total potential value. But he did say that the collaboration could have a significant impact on ExonHit's fortunes, given the size of the potential market in breast cancer alone (500,000 women underwent mammography tests in France alone last year).

Tocqué said it was too early to say when clinical trials of a test for breast cancer would begin, because there still were several validation stages to go through.

ExonHit, Affymetrix Pool Microarray Technologies

Meanwhile, ExonHit Therapeutics concluded a supply and service provider agreement with Affymetrix Inc., of Gaithersburg, Md., for the combination of the latter's GeneChip microarray platform with ExonHit's SpliceArray alternative RNA-splicing technology.

SpliceArray is a new-generation of microarrays with content and patented probe design that help detect all known transcripts, including alternative spliced variants. ExonHit in September concluded a worldwide marketing agreement for the distribution of products embodying that technology with Agilent Technologies, of Palo Alto, Calif.

The first custom-designed GeneChip arrays featuring ExonHit's SpliceArray content are expected to be available on the Affymetrix microarray platform by the year's end. ExonHit so far has developed SpliceArrays for five gene families - G-protein-coupled receptors, ionic channels, nuclear receptors, apoptosis and cytokines - and other custom designs are planned.

BioMérieux also concluded a collaboration agreement with Affymetrix giving it access to the U.S. company's technology in support of its diagnostics activities.

Also, ExonHit filed a "document de base," or preliminary prospectus, with the French Financial Markets Authority (AMF) on Oct. 18 with the aim of launching an initial public offering on the Alternext market of the Euronext stock exchange in Paris. The IPO would be launched once the Paris-based company has obtained the AMF's approval of its definitive prospectus, which has yet to be filed, and provided market conditions are deemed favourable.

Alternext is the Euronext market dedicated to small and mid-cap stocks.