Genzyme Corporation (Nasdaq: GENZ) and Berlex Inc., a U.S. affiliate of
Schering AG, Germany (FSE: SCH), majority-owned by the Bayer Group, today
announced results from CAM307, an international Phase III clinical trial
comparing Campath(R) (alemtuzumab) with chlorambucil in previously
untreated patients with B-cell chronic lymphocytic leukemia (B-CLL). The
study data were presented at the 48th Annual Meeting of the American
Society of Hematology (ASH) in Orlando.

The study met its primary endpoint by demonstrating superior
progression free survival in patients treated with Campath versus
chlorambucil, with Campath reducing the risk of disease progression or
death by 42 percent (p=0.0001).

“Results from this study demonstrate that with up to twelve weeks of
Campath therapy, these patients achieved a median period of two years
before requiring additional treatment,” stated lead investigator Peter
Hillmen, MB, ChB, of the Leeds General Infirmary, Leeds, United Kingdom.
“The high response rates, longer progression-free survival, and extended
treatment-free intervals in these patients, in addition to other clinical
data, support that Campath is one of the most active single agents in CLL
and confirm its place as a key component of any future studies in
combination or consolidation therapy.”

Additional Study Results

As reported at ASH, and confirmed by an independent response review
panel, the secondary endpoint analyses showed that patients who received
Campath given for a median of nearly twelve weeks exhibited significantly
higher overall and complete response rates, with a manageable safety
profile, compared with those patients who were treated with chlorambucil
for a median of twenty-four weeks. The data showed a nearly 30 percent
greater (83% vs. 55%) overall response rate (ORR) among patients treated
with Campath vs. chlorambucil (p< 0.0001), and a 12-fold increase (24% vs. 2%) in complete response rates (CRR) in patients receiving Campath (p< 0.0001). In addition, it was observed that 26 percent (9 out of 34) of complete responders in the Campath arm achieved an MRD (minimal residual disease) negative response as defined by testing below the level of B-CLL detection. Of those MRD negative complete responders, all but one (8 out of 9) showed no disease progression at a median follow-up of two years following treatment. “Based on these results, Campath has demonstrated significantly better efficacy with a manageable safety profile against chlorambucil as front-line therapy in B-CLL,” stated Mark Enyedy, senior vice-president and general manager of Genzyme’s oncology business unit, who also noted that this post- approval commitment study was completed within the time frame agreed upon with the U.S. Food and Drug Administration (FDA). “We look forward to working with the FDA regarding a supplement to the product labeling to support treatment of patients earlier in the course of their disease, and we believe these data offer the basis for incorporating Campath into future front-line studies in consolidation and combination therapy, and in high-risk patients,” he added. “We’re encouraged that these data showed Campath to be a safe and tolerable therapy, while providing a significant improvement in progression- free survival,” stated Richard Nieman, M.D., vice president and head of medical affairs at Berlex. “This is good news for patients, who are in need of more effective treatment options earlier in the course of their disease.” About the study design, further results and safety The international open-label, randomized trial with 297 enrolled patients compared the efficacy and safety of Campath to chlorambucil, which is considered by many to offer the most tolerable safety profile among agents commonly used for previously untreated B-CLL patients. The study examined a primary endpoint of progression free survival (PFS) and secondary endpoints that included safety, response rate, response duration, time to alternative treatment, and overall survival. A correlation between the cytogenetic profile of the patients participating in the CAM307 trial suggests a higher ORR and CRR in patients with certain cytogenetic abnormalities. While the study was not powered to assess differences in response to treatment based on cytogenetics, results on small numbers of patients appear encouraging. In patients with a 17p deletion, a marker of poor prognosis, ORR was three times higher and PFS almost five times higher among patients receiving Campath versus those receiving chlorambucil (ORR 64% vs. 20% and PFS 10.7 months versus 2.2 months respectively); however, due to the small number of patients in this group (11 patients in the Campath arm and 10 patients in the chlorambucil arm), this trend did not reach statistical significance. Overall, the tolerability profile for Campath was predictable and manageable. Although rates of grade 3-4 neutropenia, leukopenia and lymphopenia were higher in the Campath arm, there were no significant differences reported in febrile neutropenia, or in grade 3-4 thrombocytopenia and anemia. Only 16 percent of patients developed CMV reactivation associated with clinical signs or symptoms, all of which were managed with antiviral therapy. There was no treatment related mortality in the Campath arm, whereas one treatment-related death occurred in the chlorambucil arm. For Campath, the most common drug-related events, excluding CMV-related adverse events and occurring in at least 10 percent of patients, were pyrexia, chills, nausea, urticaria, hypotension and rash, whereas for chlorambucil, they were nausea and vomiting. Excluding adverse events associated with CMV reactivation, the only treatment-related grade 3-4 adverse event in the Campath arm occurring in more than five percent of patients was pyrexia. In the results of this trial, serious adverse events related to treatment occurred in 27 percent of Campath patients and seven percent of patients on chlorambucil. Hospitalization for CMV reactivation in some countries contributed to the difference in SAE frequency between the two treatment arms in this trial. The trial randomized 297 previously untreated patients at 44 medical centers in the United States and Europe. Patients were treated with either 30 mg of Campath intravenously three times per week for a maximum of 12 weeks, inclusive of dose escalation periods, or 40 mg/m