Mannatech Enters Into Exclusive Purchase Arrangement

Mannatech Enters Into Exclusive Arrangement to Purchase Plant Extract Recognized for Its Health Benefits COPPELL, TX -- (MARKET WIRE) -- September 26, 2006 -- (NASDAQ: MTEX) Mannatech, Incorporated announced today it has entered into an exclusive arrangement with Swiss-based Lonza to purchase and market worldwide a beneficial dietary fiber harvested from the American larch tree.

The agreement stipulates that Mannatech will be the only company allowed to purchase the fiber, arabinogalactan, from Lonza when it is to be used in nutritional supplements containing any two of the following ingredients: naturally derived gums and resins, aloe extract, algal extract or glucosamine. All these ingredients are found in Mannatech's flagship Ambrotose complex, the company's proprietary and best-selling nutritional supplement containing a patented blend of plant sachharides, including arabinogalactan.

Lonza currently is the only firm harvesting the soluble and odorless fiber from the American larch. Known as one of the fastest-growing trees in North America, the larch was a staple among early Native Americans, who used the tree's resin, leaves and bark for medicinal food and cosmetic applications. Arabinogalactan, which is the most abundant ingredient in Ambrotose, contains dietary sugars shown to benefit the immune system.