Monday, Mar 13, 2000

Genentech Announces Clinical Trials Testing TNKase (Tenecteplase) with Leading Anti-Thrombotics for Treatment of Heart Attack

Four Studies Pair Clot-Buster with Varying Combinations of Adjunctive Agents to Seek Improvements for Heart Attack Patients

South San Francisco, Calif. -- March 13, 2000 --

Genentech, Inc. (NYSE: DNA) today announced plans to collaborate with other major pharmaceutical manufacturers to test the new, single-bolus thrombolytic, TNKase™ (Tenecteplase), in combination with various leading anti-thrombotic agents in the treatment of acute myocardial infarction (AMI), or heart attack, as part of four clinical trials involving nearly 9,000 patients. TNKase is currently under regulatory review by the U.S. Food and Drug Administration (FDA) and the European Regulatory Authority for marketing approval for the treatment of AMI.

The goal of the comprehensive trial plan, commenced during the first quarter of 2000, is to assess whether new combination therapy strategies -- using varying doses of the single-bolus thrombolytic, anti-platelet agents (GP IIb-IIIa inhibitors), and low-molecular- weight or unfractionated heparin -- can improve coronary artery patency and clinical outcomes for patients suffering AMI.

"This important collaboration with our trial partners demonstrates our collective commitment to seeking the best possible outcomes for heart attack patients and the most reliable, convenient therapy regimens for physicians," said Susan D. Hellmann, M.D., M.P.H, executive vice president, Development and Product Operations, and chief medical officer at Genentech.

The largest of the studies is ASSENT 3 (ASsessment of the Safety and Efficacy of New Thrombolytic Regimens), a multicenter trial that will enroll 6,000 heart attack patients at more than 700 U.S. and international sites. It is co-sponsored by Boehringer Ingelheim, Genentech's international marketing partner for Activase? (Alteplase, recombinant) and TNKase™ (Tenecteplase), and with Aventis Pharmaceuticals, makers of Lovenox? (enoxaparin sodium) Injection, the world's leading low-molecular-weight heparin. ASSENT 3 will begin first in Europe and will start in the U.S. pending final FDA review of the trial.

In ASSENT 3, patients presenting within six hours of symptom onset will be randomized into three parallel treatment groups receiving varying doses of TNKase with heparin sodium (Group A), with enoxaparin sodium (Group B), or with the anti-platelet agent ReoPro™ (abciximab), manufactured by Centocor Pharmaceuticals, and heparin sodium (Group C). Trial investigators will evaluate combined clinical endpoints that include death, AMI, refractory ischemia, intracranial hemorrhage and major bleeding.

An additional 1,000 patients will be randomized into a satellite study, ASSENT 3 Plus, investigating pre-hospital administration of either TNKase with enoxaparin sodium or TNKase with heparin sodium.

INTEGRITI (INTEGRIlin and Tenecteplase in Acute Myocardial Infarction), announced last year during the American Heart Association's Annual Scientific Sessions, is a collaboration between COR Therapeutics, Inc., Schering-Plough Corporation and Genentech to study TNKase with INTEGRILIN? (eptifibatide) Injection, an anti-platelet agent. The trial is expected to enroll nearly 400 patients and is designed to determine the appropriate dosing regimen that yields optimal reperfusion, or TIMI 3 flow, as measured via coronary angiography.

FASTER (Fibrinolytic and Aggrastat ST Elevation Resolution), sponsored by Merck & Co., Inc., in collaboration with Genentech, will enroll up to 800 patients and will examine TNKase at three different dosing levels, all administered with Aggrastat? (tirofiban HCI), Merck's anti-platelet agent, and heparin sodium. An additional arm of the trial will include TNKase with heparin. Investigators will evaluate the rate of complete coronary reperfusion and ST segment resolution produced by each dosing regimen.

ENTIRE (ENoxaparin and TNK-tPA with or without GP IIb/IIIa Inhibitor as REperfusion strategy in ST elevation MI), also referred to as TIMI 23, will examine TIMI flows through coronary angiography, utilizing varying dosing regimens of TNKase™ (Tenecteplase), the low-molecular-weight heparin Lovenox, the anti-platelet agent ReoPro, and heparin sodium. The trial is expected to enroll nearly 600 patients and is sponsored by Aventis in collaboration with Genentech.

A bioengineered plasminogen activator, TNKase is similar to Activase, which is a recombinant version of naturally-occurring tissue plasminogen activator (t-PA). TNKase, administered as a patient-specific, single bolus dose, has been designed with a prolonged half-life and increased specificity to fibrin, a key component of intracoronary clots, making it compatible for study with adjunctive treatments.

Heart attacks strike more than 1.1 million people in the United States and kill approximately 500,000 each year. 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.

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

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