Genentech, Inc. and Biogen Idec have announced that two global Phase III studies in chronic lymphocytic leukemia (CLL), CLL8 and REACH, showed Rituxan (rituximab) plus chemotherapy significantly increased the time patients lived without their disease advancing, as defined by the primary endpoint of progression-free survival (PFS), when compared to chemotherapy alone.
No new safety signals were observed in either of these studies and the safety profile was consistent with previous experience with Rituxan. Results from both studies were featured today during a press briefing at the 50th Annual Meeting of the American Society of Hematology (ASH) in San Francisco.
“These are among the largest studies ever conducted in chronic lymphocytic leukemia and are significant for patients with newly diagnosed or relapsed disease,” said David Schenkein, M.D., Genentech's senior vice president, Clinical Oncology and Hematology. “These data show that adding Rituxan to chemotherapy improved both progression-free survival and reduced patients' tumor burden.”
In CLL8, patients who received Rituxan plus chemotherapy first-line had a 69 percent improvement in PFS compared to patients receiving chemotherapy alone (based on a hazard ratio of 0.59; p<0.0001). The improvement in PFS can also be referred to as a 41 percent reduction in the risk of cancer progression or death. Patients who received Rituxan plus chemotherapy had a median PFS of 42.8 months compared to 32.3 months for those who received chemotherapy alone.
In REACH, patients who received Rituxan plus chemotherapy second-line experienced a 54 percent improvement in PFS compared to patients receiving chemotherapy alone (based on a hazard ratio of 0.65; p=0.0002) as assessed by the treating physicians in the study (investigator-assessed). The improvement in PFS can also be referred to as a 35 percent reduction in the risk of cancer progression or death. Patients who received Rituxan plus chemotherapy had a median PFS of 30.6 months compared to 20.6 months for those who received chemotherapy alone.
An independent review of the PFS primary endpoint for REACH is expected to be complete early next year for U.S. regulatory purposes.
“Adding Rituxan to chemotherapy may be an additional option beyond chemotherapy alone for the more than 90,000 patients living with this incurable disease,” said Cecil Pickett, Ph.D., Biogen Idec's president of Research and Development. “We plan to work with Genentech to submit the data from both CLL8 and REACH to the FDA for potential new indications for Rituxan in first- and second-line CLL.”
Additional CLL8 Results
Immunotherapy with Fludarabine, Cyclophosphamide and Rituximab (FCR) Versus Fludarabine and Cyclophosphamide (FC) Improves Response Rates and Progression-Free Survival (PFS) of Previously Untreated Patients with Advanced Chronic Lymphocytic Leukemia (CLL) (Abstract #325) Michael Hallek, M.D., University of Cologne, Cologne, Germany; Monday, December 8, 2008, 11:00 a.m.; Halls B & C (Moscone Center).
The overall response rate in patients receiving Rituxan plus chemotherapy first-line was 93 percent compared to 85 percent in those receiving chemotherapy alone. Complete response was achieved in 45 percent of patients compared to 23 percent, respectively.
The most common adverse events that occurred more often in the Rituxan plus chemotherapy arm included blood and lymphatic system disorders, infections and neoplasms. Severe Grade 3 or greater events that occurred more often in the Rituxan plus chemotherapy arm included hematologic toxicity (56 percent vs. 39 percent), neutropenia (34 percent vs. 21 percent) and leukocytopenia (24 percent vs. 12 percent).
Additional REACH Results
Rituximab, Fludarabine, and Cyclophosphamide (R-FC) Prolongs Progression-Free Survival in Relapsed or Refractory Chronic Lymphocytic Leukemia (CLL) Compared with FC Alone: Final Results from the International Randomized Phase III REACH Trial (Abstract #15742) Tadeusz Robak, M.D., Dept. of Hematology, Medical University, Lodz, Poland; Tuesday, December 9, 2008, 7:30 a.m.; Halls B & C (Moscone Center).
The overall response rate in patients receiving Rituxan plus chemotherapy second-line was 70 percent compared to 58 percent in those receiving chemotherapy alone. Complete response was achieved in 24 percent of patients compared to 13 percent, respectively.
The most common adverse events that occurred more often in the Rituxan plus chemotherapy arm included blood and lymphatic system disorders, infections and neoplasms. Grade 3 or greater events such as neutropenia (42 percent vs. 40 percent), febrile neutropenia (15 percent vs. 12 percent) and neoplasms (7 percent vs. 3 percent) occurred more often in the Rituxan plus chemotherapy arm.
About the CLL8 and REACH Studies
Sponsored by Roche and conducted by the German CLL Study Group, CLL8 is a global, multi-center, randomized, open-label, Phase III study that enrolled 817 patients with previously untreated (first-line) CD20-positive CLL. REACH is a global, multi-center, randomized, open-label, Phase III study that enrolled 552 patients with previously treated (second-line) CD20-positive CLL sponsored by Genentech, Biogen Idec and Roche. Both studies evaluated Rituxan plus fludarabine and cyclophosphamide chemotherapy compared with fludarabine and cyclosphosphamide alone. The primary endpoint of both studies was progression-free survival. Secondary endpoints for both studies included overall survival, event-free survival, duration of response, response rate and complete response.
About Chronic Lymphocytic Leukemia
CLL is a chronic disease that affects adults over the age of 60 and is a slow-growing type of leukemia where excess mature B-cells are found in the bone marrow. According to the American Cancer Society (ACS), CLL is the most common form of leukemia in adults, accounting for one-third of all leukemias in the U.S. More than 90,000 people are currently living with CLL. The ACS estimates that 15,000 new cases will be diagnosed and approximately 4,400 people will die from CLL this year.
About Rituxan