SOUTH SAN FRANCISCO (KCBS) – A Bay Area firm is leading a first-ever clinical trial studying whether intervention can stop Alzheimer’s from developing in people genetically predisposed to the disease.

South San Francisco-based Genentech has won the right to use its experimental drug Crenezumab in the government-backed trial.

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Genentech Executive Richard Scheller said the trial will be done in Colombia, where members of an extended family of about 5,000 people carry a gene that causes early onset Alzheimer’s, with some showing symptoms in their mid-30s.

KCBS’ Anna Duckworth Reports:

“We will test our drug in people who have this mutation prior to the onset of the disease to see if we can prevent the disease from occurring,” Scheller said.

Crenezumab has proven in patients already diagnosed with Alzheimer’s to break down build-up of a protein in the brain believed responsible for the disease’s debilitating effects. But it didn’t improve thinking and memory.

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Scheller said the clinical trial will last for five years.

“If the drug is working extremely well, we might even be able to see positive signs of efficacy after two years,” he said.

$16 million of the trial’s $100 million cost is being paid for with a U.S. Department of Health and Human Services grant.

Another $15 million is coming from a non-profit health organization with Genentech footing the remainder of the bill.

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