Genzyme Announces Results of Phase 2/3 Trial of Advanced Phosphate Binder

Date: November 18, 2009

Genzyme Corporation (Nasdaq: GENZ) today reported results of a phase 2/3 study of its advanced phosphate binder (APB). The trial met its primary endpoint, which was to show that the APB lowered phosphate levels effectively compared to placebo. However, the APB did not show a significant improvement in phosphate lowering compared to Genzyme’s Renvela^® (sevelamer carbonate). Based on these results, the company is not planning to pursue further clinical development of the APB. Genzyme was seeking to develop a product with higher potency that would more effectively bind phosphate, while maintaining all the benefits of Renvela.

In the study, Renvela and the APB both effectively lowered patients’ phosphorus levels. Most adverse events associated with both Renvela and the APB were mild in nature, and the most frequently reported events were gastrointestinal disorders.

The trial was a randomized, double-blind, placebo-controlled study that enrolled 349 adult hemodialysis patients with hyperphosphatemia. It included seven arms: low, medium and high dose APB; low, medium and high dose Renvela, and placebo. It included a two-week screening period, a two-week washout period, and a three-week treatment period.

About Genzyme

One of the world's leading biotechnology companies, Genzyme is dedicated to making a major positive impact on the lives of people with serious diseases. Since 1981, the company has grown from a small start-up to a diversified enterprise with more than 11,000 employees in locations spanning the globe and 2008 revenues of $4.6 billion.

With many established products and services helping patients in approximately 100 countries, Genzyme is a leader in the effort to develop and apply the most advanced technologies in the life sciences. The company's products and services are focused on rare inherited disorders, kidney disease, orthopaedics, cancer, transplant and immune disease, and diagnostic testing. Genzyme's commitment to innovation continues today with a substantial development program focused on these fields, as well as cardiovascular disease, neurodegenerative diseases, and other areas of unmet medical need.

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