ExonHit and bioMérieux reach an important research milestone in the molecular detection of breast cancer from blood samples

ExonHit and bioMérieux reach an important research milestone in the molecular detection of breast cancer from blood samples

Marcy l'Etoile and Paris, France - March 29, 2006. ExonHit Therapeutics, a French drug and diagnostic discovery company, and bioMérieux, a major player in the field of in vitro diagnostics, announce today that they have reached an important research milestone in the diagnosis of breast cancer.

Scientific data, which will be presented on April 4, 2006 at the 97th Annual AACR (American Association for Cancer Research) meeting in Washington, DC, USA, is expected to lead to the development of novel diagnostic tests that will enable the early detection of breast cancer from blood. Such diagnostic tests could enable clinicians to make a better therapeutic decision more quickly, thus improving the chances of successfully treating patients.

The research efforts that would enable the development of these novel molecular diagnostics in cancer are based on ExonHit’s expertise in identifying specific genetic signatures from alternative RNA splicing associated with diseases and will capitalise on
bioMérieux’s know-how in developing and commercialising diagnostic tests.

The scientific data shows that the panel of genetic signatures identified by ExonHit can clearly distinguish healthy women from those with early stage breast cancer. A total of 54 genes were able to correctly classify, with accuracy of 86.7%, a group of 92 women, 55 with stage I/II breast cancer and 37 healthy women. A prospective multi-centre clinical study in 1000 women has been initiated to validate the specificity and selectivity of the markers identified.

“These results provide a clear proof of concept that by using a well characterised set of molecular markers in blood it can be possible to develop a valuable diagnostic test for breast cancer. This is an extremely positive development, which I view as a first success in our collaboration with bioMérieux. We are very pleased to be able to be working with bioMérieux to manage a multi-centre clinical study, the next stage in the development of what we believe could be a major advance in the diagnosis of breast cancer” said Bruno Tocqué, President of the Management Board of ExonHit Therapeutics.

“Early detection of breast cancer can improve the chances of successful treatment and recovery. Today’s results offer promising prospects to address as early as possible this disease and for cancer research in general. In conjunction with other diagnostic methods, these blood tests will enable a better therapeutic decision earlier” commented
Dr Christophe Mérieux, Director of Research and Development and Medical Affairs at bioMérieux.

About the study

ExonHit has applied its gene profiling technology DATAS (Differential Analysis of Transcripts with Alternative Splicing) to the blood samples of healthy women and stage I/II breast cancer patients. This has led to the identification and isolation of a set of genes including spliced variants that were differentially expressed between diseased and healthy women. the most significant diagnostic markers have then been identified using ExonHit’s SpliceArray technology applied to Affymetrix GeneChip® microarray platform. As a result, a 54-gene signature was capable of correctly classifying 86.5% of the controls (32/37) and 92.7% of the breast cancers (51/55).

Breast cancer diagnostics

To date, mammographic screening is the most reliable method to detect breast cancer in asymptomatic patients, but this often fails to detect tumours that are less than 5 mm in size. In addition, mammograms of women with dense breast tissue are difficult to interpret. Finally, when an abnormality has been detected, further tests involving invasive steps are
needed to confirm the presence of a cancer. There is clearly a medical need for a less invasive diagnostic test for breast cancer.
Today, the WHO recommends that women over 50 undergo a screening test once every two years. This recommendation is implemented in many countries, such as France. In the United States, the National Cancer Institute recommends annual screening for women aged between 40 and 74 years. However, in reality, it is estimated that only a third of the targeted
population attends the screenings.

ExonHit and bioMérieux collaboration

The ExonHit and bioMerieux collaboration in breast cancer diagnostics was initiated in 2003. This collaboration was extended in 2005 for six additional years and expanded to other cancers and now covers a minimum of five diagnostic projects. In return for its research efforts under this collaboration, ExonHit will receive research and development payments from bioMérieux as well as development milestone payments for each diagnostic project. ExonHit will also receive royalties on the sales of marketed products.

About ExonHit Therapeutics
www.exonhit.com

ExonHit Therapeutic is the world's leader in the analysis of alternative RNA splicing, a process which when deregulated plays a key role in the onset of various diseases.
ExonHit has a multi component commercial strategy to capture the maximum value from its leadership in alternative splicing. The Company is already generating revenues from a new generation of microarrays, “SpliceArrays” that enable life science researchers to detect crucial disease-associated information. These products are marketed worldwide in conjunction with Agilent and Affymetrix. In the field of diagnostics, ExonHit has a major collaboration with bioMérieux to develop completely novel predictive blood-based cancer diagnostics, which could play a key role in improving the treatment of breast and other major cancers.
In parallel, ExonHit is developing its own therapeutic pipeline in the field of neurodegenerative diseases and cancer. The Company has advanced drug candidates into clinical trials and is evaluating several promising pre-clinical compounds. ExonHit also has a strategic partnership with Allergan, to discover and develop new therapeutics in the areas of pain, neurological diseases and ophthalmology. This collaboration provides on-going research funding to ExonHit.
Founded in 1997, ExonHit is headquartered in Paris, France and has a US facility in Gaithersburg, Maryland. The Company is listed on Alternext of Euronext Paris (ticker: ALEHT).

About bioMérieux
www.biomerieux.com

bioMérieux is a leading international diagnostics group that specialises in the field of in vitro diagnostics for clinical and industrial applications. bioMérieux designs, develops, manufactures and markets systems (i.e. reagents, instruments and software) used in:
Clinical applications: the diagnosis of infectious diseases such as hepatitis, HIV, tuberculosis and respiratory illnesses, as well as pathologies such as cardiovascular diseases and cancer, based on the analysis of biological samples (such as blood, saliva or urine); and Industrial applications: the microbiological analysis of food, environments (such as water and air), surfaces and pharmaceutical and cosmetic products, based on the analysis of product or environmental samples.
In 2005, bioMérieux sales reached 994 million euros. The company is present in more than 130 countries through 35 subsidiaries and a large network of distributors, which positions the company well to benefit from the growth potential of the in vitro diagnostics market. Some important drivers that underpin this growth are aging populations and age-related illness, illnesses related to life-style and eating habits, emerging new pathogens, the development of antibiotic-resistant bacteria, the fight against bio-terrorism, the recognition of the importance of the quality of food products. bioMérieux is listed on the Eurolist of Euronext, Paris (FR0010096479 – BIM).

This press release includes only summary information and does not purport to be comprehensive. The projections, forecast and estimates of ExonHit Therapeutics which may be contained herein are for illustrative purposes only and are based on management’s current views and assumptions. Such projections, forecast and estimates involve known and unknown risks and uncertainties, as described at Section 4.2 “Facteurs de risque” (Risk Factors) of the Document de Base available on ExonHit Therapeutics’ website (www.exonhit.com), that may cause actual results, performance or events to differ materially from those anticipated in the summary information.
In addition, ExonHit Therapeutics, its shareholders, and its affiliates, directors, officers, advisors and employees have not verified the accuracy of, and make no representations or warranties in relation to, statistical data or predictions contained in this press release that were taken or derived.