ARIAD and Zygogen Establish Zebrafish Genomics Collaboration.

Business & Biotechnology Editors

CAMBRIDGE, Mass. & ATLANTA--(BUSINESS WIRE)--May 23, 2001

ARIAD Pharmaceuticals, Inc. (Nasdaq: ARIA) and Zygogen, LLC, a privately held drug discovery and genomics company, today announced the establishment of a collaboration to develop a joint technology platform based on the use of ARIAD's gene regulation technology in Zygogen's transgenic zebrafish models. The companies will combine the ARGENT system for small-molecule regulation of cellular processes with Zygogen's Z-Tag fluorescent-tagging technology to create sophisticated vertebrate disease models for use in functional genomics by pharmaceutical and biotechnology companies. Commercial terms were not disclosed.

Zebrafish, an emerging model organism, has direct relevance to the study of human disease and may become a cost-effective, high-throughput alternative to mouse models, the current standard for analysis and modeling of vertebrate development and pathology. Through the use of Zygogen's proprietary fluorescent-tagging technology, specific organs and cell lineages in transgenic zebrafish can be designed to fluoresce, broadening the use of zebrafish for disease models and drug screening.

The ARGENT gene regulation system has been adapted and optimized for rapid, high-throughput, stringent analysis of in vivo gene function. The enhanced ARGENT system overcomes key limitations of alternative approaches to controlling genes. Important distinguishing features of the ARGENT technology include extremely "tight" regulation of genes, dose-dependent modulation of gene expression using cell-permeable, small-molecule compounds, and extremely robust expression of activated genes.

The integrated use of the complimentary ARIAD and Zygogen technologies should provide a new approach to characterization of existing genes of unknown function, identification and validation of novel potential drug targets, development of relatively low-cost vertebrate models of human disease and screening of drug candidates for therapeutic activity and toxicity.

"Our new partnership with ARIAD is extremely exciting for Zygogen. The combination of two proprietary technologies should lead to more sophisticated disease modeling in zebrafish and further validation of the potential of zebrafish in functional genomics and drug screening," said Nina Sawczuk, co-founder and chief executive officer of Zygogen.

"Zygogen's leadership position in zebrafish genomics makes it an ideal collaborator for ARIAD. The joint technology platform should facilitate rapid and accurate validation of genes and proteins as targets for drug discovery and accelerate the drug discovery process," said Harvey J. Berger, M.D., chairman and chief executive officer of ARIAD. "We anticipate that this will be the first of a series of collaborations and strategic alliances on the use of our gene regulation technology in functional genomics and proteomics."

Zygogen, LLC is a privately held, Atlanta-based drug discovery and genomics company that utilizes transgenic zebrafish to develop models for human disease and screen for drug candidates. Zygogen uses its proprietary Z-Tag(TM) fluorescent-tagging technology to define gene function and screen for drug candidates in three therapeutic areas: angiogenesis, neurodegeneration and cardiovascular disease. The Z-Tag technology enables Zygogen to design transgenic zebrafish that fluoresce allowing for development of relevant models of human disease that can be used for secondary screening.

Additional information about Zygogen, LLC can be found on the web at www.zygogen.com.

ARIAD is developing a pipeline of innovative pharmaceutical products based on small-molecule drugs and its proprietary gene regulation technology platforms. The Company effectively integrates functional genomics and proteomics, protein engineering, and structure-based drug design in its drug discovery process. ARIAD's lead product candidates - treatments for osteoporosis, cancer, anemia, and graft-vs-host disease, the major limitation of allogeneic bone marrow transplantation - all work through small-molecule regulation of cellular processes. ARIAD's benchmark gene regulation technologies, ARGENT(TM), RPD(TM), and RGE(TM), have been licensed to hundreds of academic institutions worldwide for scientific research. Commercial licenses to these technologies also are available to pharmaceutical and biotechnology companies to accelerate their drug discovery efforts and for collaborative development of novel products.

Additional information about ARIAD Pharmaceuticals can be found on the web at www.ariad.com.

Some of the matters discussed in this news release are forward-looking statements that involve risks and uncertainties, which include, but are not limited to, risks and uncertainties regarding ARIAD's operations and the success of its collaborations, as well as risks and uncertainties relating to economic conditions, markets, products, clinical and preclinical studies, competition, intellectual property, services and prices, key employees, future capital needs, dependence on its collaborators and other factors discussed under the heading "Cautionary Statement Regarding Forward-Looking Statements" in ARIAD's Annual Report on Form 10-K for the fiscal year ended December 31, 2000 filed with the Securities and Exchange Commission.