Tuesday, May 29, 1990

Genentech Announces Potential Therapy for Cystic Fibrosis

South San Francisco, Calif. -- May 29, 1990 --

Genentech, Inc. announced that it filed an investigational new drug (IND) application this month with the U.S. Food and Drug Administration (FDA) for a drug which may be useful in the management of cystic fibrosis. The company expects to begin human clinical trials for DNase, a mucus-dissolving enzyme, within the next few months.

Persistent, thick secretions which clog the lungs are a frequent occurrence in patients with cystic fibrosis, the most common fatal genetic disease in the United States. It afflicts approximately 30,000 children and young adults who usually die from respiratory failure brought on by repeated lung infections. Median survival age for cystic fibrosis patients is 28 years. To date, no approved therapy exists that effectively shortens the course of lung infections by dissolving excessive and thick infected mucus secretions.

"If studies in humans demonstrate that DNase is effective in dissolving infected mucus in cystic fibrosis patients' lungs, then it should prolong and improve the quality of their lives," said Steven Shak, M.D.,Genentech director of immunobiology. Shak, who conceived of this approach and led the team that developed DNase, presented results of in vitro studies of the molecule's activity at the annual meeting of the American Federation for Clinical Research earlier this month.

The thickness of infected mucus secretions is due to the large amounts of extracellular DNA, which is released by the inflammatory cells that accumulate to fight the infection. DNase, an enzyme that dissolves the extracellular DNA, has been found, in preclinical studies, to be effective in liquefying secretions obtained from the lungs of patients with cystic fibrosis.

An earlier form of DNase, derived from cow pancreas, was shown to have beneficial effect in humans, but is no longer available. Reasoning that the mucolytic properties of DNase could be used to dissolve thick secretions, Shak and his colleagues cloned, sequenced, and have produced a purified human DNase from genetically engineered cells. Since the recombinant molecule mimics the natural human enzyme normally present in blood and saliva, few allergic responses to it are anticipated.

The company plans to test aerosolized administration of DNase first in young adults with cystic fibrosis to determine its safety and appropriate dosing regimens. If proven safe, studies in children will follow.

"The continued development of DNase is the next proper and responsible action in the fight against the devastating effects of this disease," said Robert K. Dresing, president and chief executive officer of the Cystic Fibrosis Foundation. "The results of the clinical trials will be important guides to measuring the potential impact DNase might have on the lives of children and young adults with cystic fibrosis."

G. Kirk Raab, president and chief executive officer of Genentech said, "DNase is a wonderful example of the potential of biotechnology to address special needs. It is a tribute to the valuable incentives of the Orphan Drug Act and a solid reason why the Act should not be changed." Genentech plans to file for orphan drug designation for DNase for the treatment of cystic fibrosis.

Other indications for which DNase's therapeutic potential will be studied are bacterial pneumonia, chronic bronchitis and emphysema.

Genentech is a leading biotechnology company focusing on the development, manufacture and marketing of pharmaceuticals produced by recombinant DNA technology.

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