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Milwaukee area biotech ZyStor seeks more funding

Wauwatosa, Wis.ZyStor Therapeutics, Inc. will seek additional venture funding this year in advance of filing for an investigational new drug application, president and CEO Loren G. Peterson said.

Peterson explained the company's plans during an informal gathering at the Innovation Monday program. He said ZyStor, which is developing enzyme replacement therapies, would seek additional financing before filing the application for its lead product in early 2007. "We intend to raise $10 to $15 million this summer or fall to start clinical trials," he stated.

The next round of funding would follow one completed in September 2004, when Mason Wells and Venture Investors led a syndicate of seven venture funds that participated in ZyStor's $8.5 million financing. The syndicate also included Prolog Ventures, the State of Wisconsin Investment Board, Hexagon Investments, Apjohn Ventures, and Stonehenge Capital. ZyStor moved to Milwaukee from St. Louis as a condition for the funding. It had moved to St. Louis from Cambridge, Mass.

"That money will get us through next year, and the next stage will involve raising money for clinical trials," Peterson reiterated.

ZyStor, now located in the Technology Innovation Center at Milwaukee County Research Park, is working to develop enzyme replacement therapies to better treat rare genetic disorders known as Lysosomal Storage Diseases. LSDs are a class of more than 40 genetic diseases, each caused by the lack of a specific lysosomal enzyme in human cells. Lysosomes act as a cellular recycling center where macromolecules are broken down into their component parts, and the absence of any lysosomal enzyme causes a toxic accumulation of undigested macromolecules within certain cells. This impairs cellular and tissue function, and causes painful disabilities.
Such disabilities are rare, but those afflicted can die at an early age, and existing drug therapies have proven inadequate. "I think one child born in Wisconsin each year has an LSD, which is how rare they are," Peterson said.

To be effective, the therapeutic enzyme must be delivered to the appropriate cells in tissues where the storage defect manifests itself. The problem with existing enzyme therapy treatments is that too few of the therapeutic enzymes infused into patients are delivered to critical tissues, and patients must have large intravenous doses on a frequent basis.

GILT complex

ZyStor's response, Glycosylation Independent Lysosomal Targeting or GILT, has proven effective in animal testing. With this technology, a peptide tag replaces a chemical component found on some of the enzyme's carbohydrates and is embedded within the therapeutic enzyme to promote internalization into the cell. This targets the enzyme to the lysosome, and prolongs the life of enzymes in the bloodstream.

Animal experiments designed to prove the effectiveness of GILT, which was acquired from St. Louis-based Symbiontics, Inc., have successfully been completed at St. Louis University Medical School. ZyStor has initiated additional animal studies at the University of Florida for the treatment of Pompe Disease, a genetic disorder caused by a deficiency in the enzyme needed to break down glycogen, and at St. Louis University for the treatment of Fabry Disease, which is caused by the lack of the enzyme needed to metabolize lipids.

"There's no question that if the animal studies are successful, they will raise the money easily," said Daniel Broderick, managing director of Mason Wells and a member of ZyStor's board of directors. He added that investors have not shied away from supporting research into the treatment of rare genetic disorders, even though the market would appear to be limited by the rarity of the disease. Genzyme Corp., the Massachusetts life science company that acquired Madison's Bone Care International, has built a $2.7 billion corporation on the treatment of rare genetic diseases, Broderick noted.

ZyStor hopes to partner with leading pharmaceutical companies for the development of enzyme replacement therapies. The company has an RFP out to prospective clinical contract manufacturers, and Peterson, a CPA by trade, has assembled a product development team to work on issues related to manufacturing. ZyStor has 11 employees overall, but will need to add one or two during the clinical trials.

"At this point, my best guess is that the company will be able to commercialize a product within three years," Peterson said.

Previous articles on ZyStor

Lone Wisconsin firm to present at InvestMidwest

ZyStor receives first funding and buys theraputics for rare diseases


anne rasmussen responded 9 years ago: #1

I wish I could contribute, but keep up the good work..arr

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