Longtime Silicon Valley life sciences executive, Brian Frenzel, leads Tosk, Inc. as president and CEO. The focus of Brian Frenzel and his team is to find ways to boost the safety and effectiveness of widely used pharmaceutical products and to identify new products to block the activity of cancer genes.

1. TOSK’S FRUIT
FLY MODELS
USED IN
DISCOVERING
NEW CANCER
DRUG
THERAPIES
Brian Frenzel

2. INTRODUCTION
• Longtime Silicon Valley life sciences executive, Brian Frenzel, leads Tosk, Inc. as president
and CEO. The focus of Brian Frenzel and his team is to find ways to boost the safety and
effectiveness of widely used pharmaceutical products and to identify new products to
block the activity of cancer genes.
One of Tosk’s fundamental innovations is in the use of fruit flies, which Mr. Frenzel
describes as being a “relatively low cost, high throughput screening method” that offers
an important advantage – testing in a whole animal. Traditional drug screening methods
use cell culture, molecular modeling, or biochemical assays that lack the complex
biochemical interactions present in a whole animal model of disease.
Tosk has two distinct fly-based screening technologies. One is the Side Effect Fly™ which
makes use of normal flies to identify compounds that can block adverse side effects
associated with common cancer therapies. The other is its Genetically Modified Fly™
which utilizes fruit flies with a human cancer gene integrated within their genome.
The other technology in play is Genetically Modified Fly, which utilizes fruit flies that have
had human cancer genes integrated within their genome.