Genzyme Launches 1 mcg Hectorol Capsules

Cambridge, MA (August 10, 2009) — Genzyme Corp. announced today that it has launched a 1 mcg formulation of Hectorol® (doxercalciferol capsules). The 1 mcg capsules provide a new dosing option for patients and health care providers, in addition to the existing 0.5 mcg and 2.5 mcg capsules.

"The launch of the new 1 mcg strength of Hectorol Capsules is an example of Genzyme's ongoing effort to enhance the care of patients with chronic kidney disease," stated Dan Regan, senior vice president and general manager of Genzyme's renal business. "This formulation provides added dosing flexibility for physicians and convenience for patients."

Hectorol Capsules are indicated for the treatment of secondary hyperparathyroidism in patients with stage 3 or stage 4 chronic kidney disease (CKD); the recommended starting dose for these patients is 1 mcg per day. Hectorol Capsules are also indicated for CKD patients who are on dialysis.? Hectorol consistently repletes vitamin D hormone to provide effective iPTH reduction with minimal impact on serum calcium and phosphorus levels. In April 2009, Genzyme launched a vial formulation of Hectorol Injection to replace the ampule that had previously been available. For more information, please visit www.hectorol.com

Important Treatment Considerations

Hectorol is indicated for the treatment of secondary hyperparathyroidism in patients with stage 3 or stage 4 CKD (capsules) and in patients with CKD on dialysis (capsules and injection). Hectorol is contraindicated in patients with a tendency towards hypercalcemia or evidence of vitamin D toxicity. Overdosage of any form of vitamin D is dangerous. Acute hypercalcemia may exacerbate tendencies for cardiac arrhythmias and seizures and may potentiate the action of digitalis drugs. Chronic hypercalcemia can lead to generalized vascular and soft tissue calcification. Pharmacologic doses of vitamin D and its derivatives should be withheld during Hectorol treatment to avoid possible additive effects and hypercalcemia. Magnesium-containing antacids and Hectorol should not be administered concomitantly. Adverse effects of Hectorol treatment are: hypercalcemia, hyperphosphatemia, hypercalciuria, and oversuppression of iPTH. Adverse events reported by = 5% of the Hectorol-treated predialysis patients included: infection, chest pain, constipation, dyspepsia, anemia, dehydration, depression, hypertonia, insomnia, paresthesia, increased cough, dyspnea, and rhinitis. Adverse events reported by = 5% of the Hectorol-treated dialysis patients included: headache, malaise, bradycardia, nausea/vomiting, edema, dizziness, dyspnea, and pruritus. Please see full prescribing information at www.hectorol.com or call Genzyme Medical Information at 1-800-847-0069.

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 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.

Genzyme's press releases and other company information are available at www.genzyme.com and by calling Genzyme's investor information line at 1-800-905-4369 within the United States or 1-678-999-4572 outside the United States.

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