Bendamustine compared with chlorambucil in previously untreated patients with chronic lymphocytic leukaemia: updated results of a randomized phase III trial.

The efficacy of bendamustine versus chlorambucil in a phase III trial of previously untreated patients with Binet stage B/C chronic lymphocytic leukaemia (CLL) was re-evaluated after a median observation time of 54 months in May 2010. Overall survival (OS) was analysed for the first time. At follow-up, investigator-assessed complete response (CR) rate (21·0% vs 10·8%), median progression-free survival (21·2 vs 8·8 months; P < 0·0001; hazard ratio 2·83) and time to next treatment (31·7 vs 10·1 months; P < 0·0001) were improved for bendamustine over chlorambucil. OS was not different between groups for all patients or those ≤65 years, >65 years, responders and non-responders. However, patients with objective response or a CR experienced a significantly longer OS than non-responders or those without a CR. Significantly more patients on chlorambucil progressed to second/further lines of treatment compared with those on bendamustine (78·3% vs 63·6%; P = 0·004). The benefits of bendamustine over chlorambucil were achieved without reducing quality of life. In conclusion, bendamustine is significantly more effective than chlorambucil in previously untreated CLL patients, with the achievement of a CR or objective response appearing to prolong OS. Bendamustine should be considered as a preferred first-line option over chlorambucil for CLL patients ineligible for fludarabine, cyclophosphamide and rituximab.

Mesenchymal stem cells remain of host origin even a long time after allogeneic peripheral blood stem cell or bone marrow transplantation.

OBJECTIVE: Plasticity of hematopoietic stem cells (HSC) has gained major interest in stem cell research. In order to investigate whether HSC may differentiate into mesenchymal stem cells (MSC), we assessed chimerism in peripheral blood (PB), mononuclear cell fractions (MNC) of bone marrow, and MSC derived from bone marrow (BM) from 27 up to 4225 days after allogeneic transplantation. PATIENTS AND METHODS: We applied fluorescence in situ hybridization using X/Y gene probes in sex-mismatched and STR-PCR in sex-matched patients. MSC could have been generated in 27 of 55 bone marrow samples derived from 20 patients. Fifteen patients received peripheral blood stem cell transplants (PBSCT), including CD34-selected PBSCT in two. Five patients received bone marrow. RESULTS: While all patients had chimerism in PB and MNC of the BM, in all but one patient BM-derived MSC were of recipient origin. This single patient showed reproducibly MSC of donor origin in a frequency of 1% after having received a CD34-selected PBSCT. Looking at graft collections, MSCs were easily generated from BM specimens, while no MSC could be derived from PBSC samples. CONCLUSION: Even though HSC have been found to differentiate into a variety of nonhematological cell types, they usually do not differentiate into MSC after allogeneic transplantation.

Phase III randomized study of bendamustine compared with chlorambucil in previously untreated patients with chronic lymphocytic leukemia.

PURPOSE: This randomized, open-label, parallel-group, multicenter study was designed to compare the efficacy and safety of bendamustine and chlorambucil in previously untreated patients with advanced (Binet stage B or C) chronic lymphocytic leukemia (CLL). PATIENTS AND METHODS: Patients (

CD34-related coexpression of MDR1 and BCRP indicates a clinically resistant phenotype in patients with acute myeloid leukemia (AML) of older age.

Clinical resistance to chemotherapy in acute myeloid leukemia (AML) is associated with the expression of the multidrug resistance (MDR) proteins P-glycoprotein, encoded by the MDR1/ABCB1 gene, multidrug resistant-related protein (MRP/ABCC1), the lung resistance-related protein (LRP), or major vault protein (MVP), and the breast cancer resistance protein (BCRP/ABCG2). The clinical value of MDR1, MRP1, LRP/MVP, and BCRP messenger RNA (mRNA) expression was prospectively studied in 154 newly diagnosed AML patients >or=60 years who were treated in a multicenter, randomized phase 3 trial. Expression of MDR1 and BCRP showed a negative whereas MRP1 and LRP showed a positive correlation with high white blood cell count (respectively, p < 0.05, p < 0.001, p < 0.001 and p < 0.001). Higher BCRP mRNA was associated with secondary AML (p < 0.05). MDR1 and BCRP mRNA were highly significantly associated (p < 0.001), as were MRP1 and LRP mRNA (p < 0.001) expression. Univariate regression analyses revealed that CD34 expression, increasing MDR1 mRNA as well as MDR1/BCRP coexpression, were associated with a lower complete response (CR) rate and with worse event-free survival and overall survival. When adjusted for other prognostic actors, only CD34-related MDR1/BCRP coexpression remained significantly associated with a lower CR rate (p = 0.03), thereby identifying a clinically resistant subgroup of elderly AML patients.

The value of the MDR1 reversal agent PSC-833 in addition to daunorubicin and cytarabine in the treatment of elderly patients with previously untreated acute myeloid leukemia (AML), in relation to MDR1 status at diagnosis.

To determine whether MDR1 reversal by the addition of the P-glycoprotein (P-gp) inhibitor PSC-833 to standard induction chemotherapy would improve event-free survival (EFS), 419 untreated patients with acute myeloid leukemia (AML) aged 60 years and older were randomized to receive 2 induction cycles of daunorubicin and cytarabine with or without PSC-833. Patients in complete remission were then given 1 consolidation cycle without PSC-833. Neither complete response (CR) rate (54% versus 48%; P = .22), 5-year EFS (7% versus 8%; P = .53), disease-free survival (DFS; 13% versus 17%; P = .06) nor overall survival (OS; 10% in both arms; P = .52) were significantly improved in the PSC-833 arm. An integrated P-gp score (IPS) was determined based on P-gp function and P-gp expression in AML cells obtained prior to treatment. A higher IPS was associated with a significantly lower CR rate and worse EFS and OS. There was no significant interaction between IPS and treatment arm with respect to CR rate and survival, indicating also a lack of benefit of PSC-833 in P-gp-positive patients. The role of strategies aimed at inhibitory P-gp and other drug-resistance mechanisms continues to be defined in the treatment of patients with AML.