ARIAD Receives First Patent On Novel Gene Activation Technology.

Business Editors &Health/Science Writers

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Jan. 25, 2000

New Applications in Genomics, Therapeutic Protein Manufacturing and

Gene Therapy

ARIAD Pharmaceuticals, Inc. (NASDAQ:ARIA) today announced the issuance of the first in a series of anticipated new patents on its proprietary technology for activation of endogenous and engineered genes. ARIAD Gene Activation Technology involves novel methods and compositions for efficiently turning on specific genes which results in high-level production of the corresponding proteins. Activation of specific genes is the key step in a potentially wide range of commercial and clinical applications, including the activation of endogenous genes in cell culture for industrial-scale manufacturing of proteins, manipulation of gene activity for genomic analysis, and control of genes administered by gene therapy. All of these uses depend on potent gene activation resulting in sufficiently high levels of protein production to achieve the desired effects.

U.S. Patent No. 6,015,709, issued on January 18, 2000, covers a proprietary class of highly potent gene activator proteins used in the ARIAD Gene Activation Technology. They contain novel combinations of gene activator modules that provide substantial enhancements in the level of gene activation compared to naturally occurring activators. This suggests that efficient gene activation should be achievable in a broad range of cell and tissue types.

Activation of endogenous genes in a controlled manner using ARIAD Gene Activation Technology has several potential applications. High-level activation of specific genes in cultured cells may provide a means of manufacturing, on a commercial scale, therapeutic proteins, such as erythropoietin, colony stimulating factors, interferons and coagulation factors. The ability to activate natural genes with this technology should avoid the need to introduce or otherwise manipulate the target gene, which addresses certain practical and intellectual property issues relating to use of such genes. Administration of specific gene activators to patients by gene therapy also may provide a direct approach to turn on particular therapeutic genes in vivo. Experimental activation of genes also is a powerful tool for genomic analysis of gene function.

Gene activators also are integral components of the ARGENT(TM) gene therapy system for regulating protein production using orally active Dimerizer Drugs(TM). These new gene activators should expand the spectrum of proteins that can be delivered effectively by ARGENT in particular and by gene therapy in general. ARIAD scientists already have incorporated the new gene activators into ARGENT-based gene delivery vectors for studies in animals.

&uot;Our newly issued patent on the ARIAD Gene Activation Technology, along with our six previously issued ARGENT patents and numerous additional patent applications in prosecution, should provide ARIAD with a proprietary basis for the commercial development of products using our gene regulation and gene activation technology-platforms,&uot; said Harvey J. Berger, M.D., chairman and chief executive officer of ARIAD.

Copies of the new ARIAD Patent (U.S. Patent No. 6,015,709), as well as the six previously issued patents on ARGENT (U.S. Patent Nos. 5,830,462; 5,834,266; 5,869,337; 5,871,753; 5,994,313 and 6,011,018), are available on the World Wide Web at http://www.uspto.gov/web/menu/search.html.

ARIAD Pharmaceuticals (www.ariad.com) is engaged in the discovery and development of novel therapeutics based on signal transduction technology. The Company is developing small-molecule drugs to block intracellular signaling pathways that play a critical role in major diseases, including osteoporosis and various immune-related disorders. ARIAD is also developing ARGENT(TM), a proprietary gene regulation technology for orally active protein therapy and cellular immunotherapy that utilizes small-molecule drugs to control intracellular signaling pathways in engineered cells.

Some of the matters discussed in this news release are forward-looking statements that involve risks and uncertainties. For example, there can be no assurance that if a patent is issued, any such patent would be enforceable or provide meaningful protection. Other risks and uncertainties include, but are not limited to, risks and uncertainties regarding the Company's preclinical studies, the ability of the Company to conduct clinical trials of its products and the success of such trials, as well as risks and uncertainties relating to economic conditions, markets, products, competition, intellectual property, services and prices, key employees, future capital needs, dependence on our collaborators and other factors under the heading &uot;Cautionary Statement Regarding Forward-Looking Statements&uot; in ARIAD's Annual Report on Form 10-K for the fiscal year ended December 31, 1998 filed with the Securities and Exchange Commission.