PCR, FCR Have Significant Activity In B-cell Chronic Lymphocytic Leukemia
A leading cancer researcher affiliated with the US Oncology Research Network will present findings from a randomized, multicenter Phase III trial that compared FCR and PCR in patients with B-cell chronic lymphocytic leukemia (CLL).
The study results will be given in an oral presentation by Dr. Craig Reynolds of Ocala Oncology Center at the 50th Annual Meeting of the American Society of Hematology (ASH) held December 6-9, 2008 in San Francisco. Dr. Reynolds is the lead investigator and serves as co-chairman, and chairman for new protocol development, of US Oncology's National Lung Cancer Research Committee.
Purine analog-based regimens have emerged as highly active regimens in the treatment of chronic lymphocytic lymphoma (CLL). Promising results have been reported with the combination of fludarabine (F), cyclophosphamide (C), and rituximab (FCR) by Keating and colleagues at the University of Texas M.D. Anderson Cancer Center. Previous US Oncology Research Network, as well as a Mayo Clinic and MSKCC trials, evaluated the combination of pentostatin (P), cyclophosphamide (C), and rituximab (PCR); results suggested similar efficacy with less infectious complications than that seen with FCR.
The current multicenter, randomized, community-based trial was conducted to compare FCR and PCR in previously untreated or minimally treated B-cell chronic lymphocytic leukemia. The primary end point of the study was infectious complications with efficacy and safety as secondary endpoints. Correlative studies of immune function were conducted by Kay and colleagues at the Mayo Clinic and will be reported separately.
"This study establishes the role of these regimens in the treatment of CCL," said Dr. Reynolds. "New therapies such as these offer hope for our patients."
The research found that both PCR and FCR have significant activity in CLL and can be given safely in the community setting. Both regimens possess significant toxicity and response rates in this multi-institution, community-based randomized trial were lower than previous Phase II trials of previously untreated patients. This trial did not demonstrate a lower infection rate with PCR using pentostatin at the 4 mg/m2 dose level. In early follow-up, no statistically significant differences with respect to overall response rate or survival were observed between FCR and PCR, although the CR rate was significantly higher with FCR.