Tuesday, Mar 9, 1999

International Trial Shows Promising Results for Genentech's New Clot Buster Compared with Activase

South San Francisco, Calif. -- March 9, 1999 --

Genentech, Inc. (NYSE: GNE) ) today announced positive results of a 17,000-patient, international, multi-center Phase III trial comparing the company's new single-bolus thrombolytic, tenecteplase, with its current, market-leading thrombolytic, Activase®; (Alteplase, recombinant). Preliminary trial results were presented during the Annual Scientific Session of the American College of Cardiology in New Orleans, March 1999.

The results of the ASSENT 2 trial (ASsessment of the Safety and Efficacy of a New Thrombolytic agent) will be submitted by Genentech as part of a biological licensing application (BLA) to the U.S. Food and Drug Administration (FDA) and simultaneously to the European Regulatory Authority by Boehringer Ingelheim during the third quarter of 1999 for approval of tenecteplase for the treatment of acute myocardial infarction (AMI), or heart attack. Boehringer Ingelheim is co-sponsor of the ASSENT 2 study, and Genentech's international marketing partner for Alteplase and developmental collaborator for tenecteplase.

With more than 1,000 sites in 29 countries, ASSENT 2 was designed as a randomized, double-blind, parallel group trial of a weight-adjusted, 30 - 50 mg single bolus of tenecteplase versus the 90-minute accelerated infusion of Activase®; (Alteplase, recombinant) in AMI patients. Final analysis of trial results will be presented during the European Society of Cardiology meeting in August, 1999 in Barcelona, Spain.

"The ASSENT 2 results demonstrate that tenecteplase may have great promise as a potential new weight-adjusted thrombolytic agent for treatment of heart attack patients, with the added convenience of single bolus administration," said Arthur D. Levinson, Ph.D., Genentech's president and chief executive officer.

A bio-engineered plasminogen activator, tenecteplase is similar to Activase, which is a recombinant version of naturally-occurring tissue plasminogen activator (t-PA). Tenecteplase has been specifically designed to prolong its half-life, increase specificity for fibrin (a key component of intracoronary clots) and increase resistance to plasminogen activator inhibitor-1 (PAI-1), a protein that can interfere with the clot-dissolving effects of both naturally-occurring and recombinant t-PA during a heart attack.

Tenecteplase has been studied in clinical trials involving more than 21,000 patients worldwide. The promising outcomes of previous studies led to Phase III testing in ASSENT 2. The most significant clinical adverse events observed in trials with tenecteplase include intracranial hemorrhage and total strokes, which are similar to those seen with other thrombolytics.

Activase, the active control in ASSENT 2, is the most widely-used thrombolytic and has been marketed for treatment of AMI in the United States and Europe since 1987. Since that time, it has been administered to more than one million heart attack patients. In addition, it is indicated for the treatment of acute, massive pulmonary embolism, and is the only emergency therapy approved by the FDA for the treatment of acute ischemic stroke within three hours of the onset of symptoms.

Heart attacks strike more than 1.1 million people in the United States each year and kill approximately 500,000. Therapies and procedures that open the blocked artery causing the heart attack have been shown to significantly improve survival, but they must be administered within a few short hours of the onset of symptoms, which include chest pain radiating down the arm, difficulty breathing, "cold sweats," and nausea. Unfortunately, many heart attack victims deny they are experiencing symptoms and delay seeking the emergency medical care that could save their lives.

Boehringer Ingelheim, headquartered in Ingelheim, Germany, and Genentech have actively collaborated since 1983 on the clinical development of novel thrombolytic agents, namely Alteplase and tenecteplase.

Boehringer Ingelheim ranks among the top 20 pharmaceutical companies in the world. It reported revenues exceeding DM 8.2 billion in 1997. The corporation has approximately 160 affiliated companies and conducts business on every continent. Its product range is focused on human pharmaceuticals -- hospital, prescription and self-medication -- as well as animal health.

Genentech, Inc. is a leading biotechnology company that discovers, develops, manufactures and markets human pharmaceuticals for significant unmet medical needs. Twelve of the currently marketed biotechnology products stem from Genentech science. Genentech markets seven biotechnology products directly in the United States. The company has headquarters in South San Francisco, California, and is traded on the New York Stock Exchange and the Pacific Exchange under the symbol GNE.

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