ARIAD to Present Key Advances in Regulated Gene Therapy and Gene Activation At Keystone Symposium.

Business & Health Editors

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Jan. 10, 2000

Primate studies show ARGENT(TM) erythropoietin production for over 450 days

ARIAD Pharmaceuticals, Inc. (Nasdaq: "ARIA") today announced that its proprietary gene regulation and gene activation technologies will be the subject of multiple presentations at the annual Gene Therapy Symposium at Keystone, Colorado.

On January 10, 2000, Victor M. Rivera, Ph.D., project manager, regulated gene therapy, for ARIAD will present a talk entitled "Regulated Delivery of Secreted Proteins" detailing the latest progress in preclinical studies on the delivery of therapeutic proteins, such as erythropoietin (EPO) and insulin, using gene therapy. These advances include the recent development of new and proprietary components of the ARIAD Regulated Gene Expression Technology (ARGENT(TM)) system, which significantly improve the effectiveness of protein delivery. They also have broad applicability in genomics and protein manufacturing. An accompanying poster presentation describes characterization of these new components in different vector systems.

Gene activator proteins are used to control the expression of therapeutic genes in regulated gene therapy. By using ARGENT-based gene activators, protein delivery can be controlled by an orally active small-molecule drug. Effective therapy depends on producing sufficient quantities of the protein, which, in turn, is limited by the potency of the gene activator protein. ARIAD scientists have discovered novel gene activators that are the most potent described to date and have devised methods to further take advantage of their potency by "bundling" a cluster of gene activator proteins together instead of relying on an individual molecule. The new ARGENT components provide dramatic increases in the expression of genes under conditions of clinical gene therapy, suggesting that this technology will be critical to the successful development of gene therapy products. ARIAD scientists have incorporated this new technology into gene delivery vectors for testing in animal models. The bundling technology was described in a recent issue of The Proceedings of the National Academy of Sciences, USA (S. Natesan et al. (1999) A general strategy to enhance the potency of chimeric transcriptional activators. 96, 13898-13903).

Dr. Rivera's talk also will include presentation of the latest results on the use of ARGENT gene therapy to deliver erythropoietin (EPO) in rhesus monkeys, generated in collaboration with the Institute for Human Gene Therapy (IHGT) at the University of Pennsylvania, led by James M. Wilson, M.D., Ph.D. As reported last year in Science, a regulated EPO gene was introduced into rhesus monkeys using an adeno-associated viral (AAV) vector administered intramuscularly. AAV vectors are non-pathogenic and contain no viral genes. Administration of the orally active drug, rapamycin, stimulated EPO production and increased the number of red blood cells. ARIAD and IHGT scientists have continued these studies and demonstrated that EPO production can be repeatedly stimulated with rapamycin in several monkeys for a period of over 450 days. The new data demonstrate the feasibility of long-term delivery of EPO by a one-time administration of gene delivery vector followed by use of an oral drug to induce protein production.

"Development of the novel ARGENT components should further broaden the applicability of our regulated gene therapy system by allowing higher blood levels of proteins to be produced," said Harvey J. Berger, M.D., chairman and chief executive officer of ARIAD. "In addition, the latest data on the ARGENT system in rhesus monkeys emphasize the broad potential of ARGENT for long-term delivery of many secreted proteins. ARGENT-based therapeutics should markedly improve the safety and efficacy of many secreted therapeutic proteins."

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, which 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 "Cautionary Statement Regarding Forward-Looking Statements" in ARIAD's Annual Report on Form 10-K for the fiscal year ended December 31, 1998 filed with the Securities and Exchange Commission.