Investor Relations

WILMINGTON, Mass.--(BW HealthWire)--Dec. 4, 2000--Charles River Laboratories, Inc. (NYSE: CRL) has entered into an agreement with the Tufts University School of Veterinary Medicine to further develop and commercialize a novel cloning technology, applied to immunodeficient mice.

The so-called "nude" mouse model has gained wide acceptance in the research community for use in infectious disease, oncology, transplantation and related immunological research. The nude mouse is among the fastest growing research models bred and sold by Charles River worldwide. Efficient cloning of this high value research model through Tufts' proprietary cloning techniques is expected to increase the utility of the model to researchers, as well as improve the efficiency with which it is produced at Charles River. In many areas of drug discovery a cloned mouse model will improve on existing models by eliminating variability and thereby improving the quality and consistency of research results.

Charles River's growth strategy includes partnering with institutions and companies that have developed cutting edge technologies that result in new or improved animal research models. Dr. Eric Overstrom of the Tufts School of Veterinary Medicine has developed a novel cloning technique that, when combined with Charles River's embryo transfer and cryopreservation capabilities, allows for a highly efficient cloning process in mouse models. Tufts University has filed a U.S. patent application on this technology.

"We're delighted to be working with Tufts in the very exciting area of cloning research. Charles River and the Tufts School of Veterinary Medicine have long worked together in pursuit of biomedical advances," commented James C. Foster, Chairman & CEO. "The world class science being conducted in Dr. Overstrom's laboratories will lead to both significant benefits to researchers who use research models such as the nude mouse, and also lead to improved efficiency of production of models at Charles River."

The agreement between Charles River and Tufts provides for sponsored research at Tufts to further refine the somatic cell cloning technique in a spontaneous mutation mouse model, and to provide statistically valid data to support efficient use of the technique for large scale commercial breeding. Charles River has obtained an exclusive license to this cloning technology in the field of use of mouse, rat and other rodent research models.

"Tufts is proud of the leadership Dr. Overstrom and his colleagues are providing in the emerging area of transgenic cloning for therapeutic human and animal treatments," said Dr. Phil Kosch, dean of the School of Veterinary Medicine. "We're committed to advancing animal and human health in everything we do on this campus, and we're looking forward to continuing our close working relationship with the widely respected scientists at Charles River Laboratories."

Longer term, a continued research partnership with Tufts may lead to the efficient creation of new genetically modified mouse models for use in developing potential pharmaceutical therapies. Charles River is also in discussions with other potential partners with proprietary animal model creation methods.

"Improved production clearly translates into animal welfare gains," continued Foster. "Longer term, we believe this cloning technique, which appears to be more efficient than others when applied to mice, rats and other small animal models, will allow us the opportunity to work closely with our customers in creating new animal models. This and similar technology partnerships under development reflect what we believe is an innovative and efficient approach to R&D in the research model segment of our business."

Tufts University is home to New England's only veterinary school, which is in North Grafton, Massachusetts. The veterinary school's Center for Animals and Public Policy offers the country's only graduate degree in the field of human/animal relationships and related public policy. In addition, the University has the country's largest residency training program in veterinary emergency and critical care, and is known worldwide for its signature programs in wildlife and international veterinary medicine.

Charles River Laboratories, based in Wilmington, Massachusetts, is a leading provider of critical research tools and integrated support services that enable innovative and efficient drug discovery and development. The Company is the global leader in providing the animal research models required in research and development for new drugs, devices and therapies. The Company also offers a broad and growing portfolio of biomedical products and services that enable customers to reduce cost, increase speed, and enhance productivity and effectiveness in drug discovery and development. Charles River's customer base spans over 50 countries, and includes all of the major pharmaceutical and biotechnology companies, as well as many leading hospitals and academic institutions. The Company operates 53 facilities in 15 countries worldwide. For additional information about Charles River Laboratories visit our website at: www.criver.com.

This document may contain "forward looking statements." Such statements involve a number of risks and uncertainties that could cause actual results to differ materially from those stated or implied by the forward looking statements, including contaminations, industry trends, new displacement technologies, outsourcing trends, USDA and FDA regulation, changes in law, acquisition integration risks, special interests groups, continued availability of products and supplies, personnel and control, and others that are described in the Risk Factors contained in Company's Registration Statement of Form S-1, as filed on June 23, 2000, and as may be updated from time to time in the Company's periodic SEC filings. The Company disclaims an intent or obligation to update forward looking statements, and otherwise claims the "safe harbor" protections for forward looking statements afforded under The Private Securities Litigation Reform Act of 1995. Charles River Laboratories International, Inc. is listed on the New York Stock Exchange under the symbol CRL.

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