Genzyme Corporation Announces Phase 3 Trial of Mozobil in non-Hodgkin's Lymphoma Meets Primary Endpoint CAMBRIDGE, Mass., July 19 -- Genzyme today announced that it has successfully completed its phase 3 trial of Mozobil(TM) (plerixafor) in non-Hodgkin's lymphoma (NHL), and that the trial has robustly met its primary and secondary endpoints. The randomized, double-blind, placebo-controlled trial included 298 patients who were undergoing a hematopoietic stem cell transplant (HSCT) for NHL at medical centers in the United States and Canada. It examined the effectiveness of Mozobil in increasing the number of hematopoietic stem cells collected for a transplant. The study compared the hematopoietic stem cell yield from patients treated with Mozobil in combination with G-CSF to patients treated with G-CSF in combination with placebo. G-CSF is the standard of care for stimulating the mobilization of stem cells from the bone marrow; Mozobil is designed to allow for the more rapid and effective release of those stem cells from the marrow into the circulating blood for collection by apheresis. In the primary efficacy endpoint, 59 percent of patients treated with a combination of Mozobil and G-CSF achieved the target threshold for collection of at least 5 million CD34+cells/kg from the peripheral blood with four or fewer days of apheresis sessions, compared with 20 percent of patients in the G-CSF/placebo group. The three-fold increase was highly statistically significant in favor of the Mozobil-treated patients (p<0.0001). The 40 percent absolute difference between the two treatment groups was nearly double the target that Genzyme prospectively defined in the protocol for the study, which was reviewed by FDA as part of the Special Protocol Assessment process. In the secondary efficacy endpoint, nearly 87 percent of patients treated with Mozobil and G-CSF achieved the minimum level of stem cells generally associated with a successful transplant (2 million CD34+cells/kg) in four or fewer days of apheresis sessions, compared with approximately 47 percent in the placebo arm. This result was also highly statistically significant in favor of the Mozobil-treated patients (p<0.0001). The other secondary efficacy endpoints were supportive of these findings, including analysis of the number of days needed to reach target ranges for stem cell mobilization, the success of engraftment, the number of days needed to engraft, and the durability of the engraftment for the first 100 days. Mozobil was well tolerated in the trial, with the most common adverse events being mild gastrointestinal effects and redness at the site of injection. There were two related serious adverse events seen in the Mozobil plus G-CSF arm, and one in the G-CSF plus placebo arm. "These are very impressive results with far-reaching clinical importance for patients undergoing a stem cell transplant for lymphoma," said Principal Investigator John F. DiPersio, M.D., Ph.D., professor, Washington University, St. Louis. "Current literature suggests that increasing the number of stem cells in circulation and the number collected at the time of apheresis may improve the outcomes of patients undergoing a stem cell transplant, reduce the costs associated with stem cell collection and, more importantly, broaden the pool of patients for whom transplantation is an option." Based on these results Genzyme expects to file for US and European approval in lymphoma in the first half of 2008. In addition, Genzyme is completing a second phase 3 trial of Mozobil in multiple myeloma, and results are expected in the coming weeks. About Mozobil Mozobil, a novel small molecule CXCR4 chemokine antagonist, has been shown in multiple earlier studies to rapidly and effectively increase the number of stem cells in circulation in the blood. Once circulating in the blood, stem cells can be collected for use in a stem cell transplant. Mozobil has been granted special protocol assessment and orphan drug status in the United States and European Union and the pivotal trials have undergone Special Protocol Assessment by the FDA and Protocol Assistance by the EMEA. Genzyme intends to commercialize Mozobil through its existing global transplant business to hematologists and hematopoietic stem cell transplant centers in more than 50 countries throughout the world. Genzyme has been developing Mozobil since its acquisition of AnorMED, Inc. in 2006. Approximately 55,000 stem cell transplants are performed each year for multiple myeloma, Hodgkin's and non-Hodgkin's lymphoma, and other conditions in markets where Genzyme has a commercial infrastructure, including the United States, Europe, Latin America and the Asian Pacific countries. 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 9,000 employees in locations spanning the globe and 2006 revenues of $3.2 billion. Genzyme has been selected by FORTUNE as one of the "100 Best Companies to Work for" in the United States. With many established products and services helping patients in nearly 90 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 diagnostic testing. Genzyme's commitment to innovation continues today with a substantial development program focused on these fields, as well as immune disease, infectious disease, and other areas of unmet medical need. This press release contains forward-looking statements, including the statements regarding: the anticipated clinical importance for patients undergoing stem cell transplants, the anticipated improvements with respect to patient outcomes, the potential increase in the number of patients for whom transplantation may become available, the timing expectations associated with the multiple myeloma phase 3 clinical trial results, Genzyme's anticipated timing associated with regulatory submissions for US and European regulatory approvals for Mozobil and Genzyme's global commercialization plans for Mozobil and its ability to leverage its existing commercial infrastructure. These statements are subject to risks and uncertainties that could cause actual results to differ materially from those projected in these forward-looking statements. These risks and uncertainties include, among others, the possibility of unfavorable multiple myeloma phase 3 clinical trial results, the failure of Mozobil to receive regulatory approvals for the label or on the schedule expected, the uncertainties of launching a new product on a global scale following receipt of applicable regulatory approvals due to misestimates of the time and resources required to do so, or for other reasons, the failure of Mozobil to receive favorable pricing or reimbursement; the possible inaccuracies of Genzyme's analysis with respect to markets and number of potential patients for Mozobil; and the risks and uncertainties described in reports filed by Genzyme with the Securities and Exchange Commission under the Securities Exchange Act of 1934, as amended, including without limitation the information under the heading "Factors Affecting Future Operating Results" in the Management's Discussion and Analysis of Financial Condition and Results of Operations section of the Genzyme Quarterly Report on Form 10-Q for the quarter ending March 31, 2007. Genzyme cautions investors not to place substantial reliance on the forward-looking statements contained in this press release. These statements speak only as of the date of this press release, and Genzyme undertakes no obligation to update or revise the statements.