Kenneth F. Bradstock

Outcome of Treatment in Adults With Acute Lymphoblastic Leukemia: Analysis of the LALA-94 Trial

PURPOSE We analyzed the benefits of a risk-adapted postremission strategy in adult lymphoblastic leukemia (ALL), and re-evaluated stem-cell transplantation (SCT) for high-risk ALL. PATIENTS AND METHODS A total of 922 adult patients entered onto the trial according to risk groups: standard-risk ALL (group 1), high-risk ALL (group 2), Philadelphia chromosome-positive ALL (group 3), and CNS-positive ALL (group 4). All received a standard four-drug/4-week induction course. Patients from group 1 who achieved a complete remission (CR) after one course of induction therapy were randomly assigned between intensive and less intensive postremission chemotherapy, whereas those who achieved CR after salvage therapy were then included in group 2. Patients in groups 2, 3, and 4 with an HLA-identical sibling were assigned to allogeneic SCT. In groups 3 and 4, autologous SCT was offered to all other patients, whereas in group 2 they were randomly assigned between chemotherapy and autologous SCT. RESULTS Overall, 771 patients achieved CR (84%). Median disease-free survival (DFS) was 17.5 months, with 3-year DFS at 37%. In group 1, the 3-year DFS rate was 41%, with no difference between arms of postremission randomization. In groups 2 and 4, the 3-year DFS rates were 38% and 44%, respectively. In group 2, autologous SCT and chemotherapy resulted in comparable median DFS. Patients with an HLA-matched sibling (groups 2 and 4) had improved DFS. Three-year DFS was 24% in group 3. CONCLUSION Allogeneic SCT improved DFS in high-risk ALL in the first CR. Autologous SCT did not confer a significant benefit over chemotherapy for high-risk ALL.

Consolidation Therapy With Low-Dose Thalidomide and Prednisolone Prolongs the Survival of Multiple Myeloma Patients Undergoing a Single Autologous Stem-Cell Transplantation Procedure

PURPOSE Thalidomide is effective in the treatment of newly diagnosed and relapsed/refractory multiple myeloma (MM). However, the role of thalidomide in the post-autologous stem cell transplantation (ASCT) context remains unclear. This study assessed whether the addition of thalidomide consolidation following ASCT would improve the durability of responses achieved and overall survival. PATIENTS AND METHODS Between January 2002 and March 2005, 269 patients with newly diagnosed MM who achieved disease stabilization or better with conventional induction chemotherapy received a single high-dose melphalan conditioned ASCT. Post-ASCT, 129 patients were randomly assigned to receive indefinite prednisolone maintenance therapy (control group) and 114 to receive the same in addition to 12 months of thalidomide consolidation (thalidomide group). The primary study end points were progression-free survival (PFS) and overall survival (OS). The secondary end point was tolerability. RESULTS After a median follow-up of 3 years, the postrandomization 3-year PFS rates were 42% and 23% (P < .001; hazard ratio [HR], 0.5; 95% CI, 0.35 to 0.71) and the OS rates were 86% and 75% (P = .004; HR, 0.41; 95% CI, 0.22 to 0.76) in the thalidomide and control groups, respectively. There was no difference in survival between groups 12 months after disease progression (79% v 77%; P = .237). Neurological toxicities were more common in the thalidomide arm but there were no differences between arms for thromboembolic events. CONCLUSION Consolidation therapy with 12 months of thalidomide combined with prednisolone prolongs survival when used after a single high-dose therapy supported ASCT in patients with newly diagnosed MM. Furthermore, thalidomide consolidation therapy did not adversely impact on survival in the subsequent salvage setting.

Effects of inhibitors of the chemokine receptor CXCR4 on acute lymphoblastic leukemia cells in vitro

Stromal cell-derived factor-1 (SDF-1) is a key regulator of the behavior of normal and leukemic precursor-B (pre-B) cells. It is possible that inhibiting SDF-1-driven processes in pre-B acute lymphoblastic leukemia (ALL) may have therapeutic implications. In this study, we examined the ability of SDF-1 inhibitors to modulate pre-B ALL cell responses to SDF-1, including chemotaxis, migration into bone marrow stroma, and stroma-supported survival and proliferation on human bone marrow stromal layers. The polyphemusin II-derived inhibitors, T140, TC140012, and T134, and the bicyclam AMD3100, effectively inhibited binding of the anti-CXCR4 monoclonal antibody 12G5 on the pre-B ALL cell line NALM6, with IC50 values of 0.9, 0.9, 0.9, and 1.9 nM, respectively. Similar results were obtained with ALL samples. T140 (0.1 μM) and AMD3100 (1 μM) completely blocked SDF-1-induced chemotaxis and attenuated the migration of pre-B ALL cells into bone marrow stromal layers. AMD3100 and TC140012 at a concentration of 50 μM significantly inhibited stroma-dependent proliferation of six and four of the eight cases tested, respectively, without reducing the cell viability. In addition, AMD3100 and TC140012 enhanced the cytotoxic and antiproliferative effects of the cytotoxic agents vincristine and dexamethasone. The ability of SDF-1 inhibitors to modulate these biologically important functions of leukemic cells warrants further investigation.

All-trans-retinoic acid, idarubicin, and IV arsenic trioxide as initial therapy in acute promyelocytic leukemia (APML4)

The treatment of acute promyelocytic leukemia has improved considerably after recognition of the effectiveness of all-trans-retinoic acid (ATRA), anthracycline-based chemotherapy, and arsenic trioxide (ATO). Here we report the use of all 3 agents in combination in an APML4 phase 2 protocol. For induction, ATO was superimposed on an ATRA and idarubicin backbone, with scheduling designed to exploit antileukemic synergy while minimizing cardiotoxicity and the severity of differentiation syndrome. Consolidation comprised 2 cycles of ATRA and ATO without chemotherapy, followed by 2 years of maintenance with ATRA, oral methotrexate, and 6-mercaptopurine. Of 124 evaluable patients, there were 4 (3.2%) early deaths, 118 (95%) hematologic complete remissions, and all 112 patients who commenced consolidation attained molecular complete remission. The 2-year rate for freedom from relapse is 97.5%, failure-free survival 88.1%, and overall survival 93.2%. These outcomes were not influenced by FLT3 mutation status, whereas failure-free survival was correlated with Sanz risk stratification (P[trend] = .03). Compared with our previously reported ATRA/idarubicin-based protocol (APML3), APML4 patients had statistically significantly improved freedom from relapse (P = .006) and failure-free survival (P = .01). In conclusion, the use of ATO in both induction and consolidation achieved excellent outcomes despite a substantial reduction in anthracycline exposure. This trial was registered at the Australian New Zealand Clinical Trials Registry (www.anzctr.org.au) as ACTRN12605000070639.

Imatinib produces significantly superior molecular responses compared to interferon alfa plus cytarabine in patients with newly diagnosed chronic myeloid leukemia in chronic phase

We analyzed molecular responses in 55 newly diagnosed chronic-phase chronic myeloid leukemia (CML) patients enrolled in a phase 3 study (the IRIS trial) comparing imatinib to interferon-alfa plus cytarabine (IFN+AraC). BCR-ABL/BCR% levels were measured by real-time quantitative RT-PCR and were significantly lower for the imatinib-treated patients at all time points up to 18 months, P<0.0001. The median levels for imatinib-treated patients continued to decrease and had not reached a plateau by 24 months. A total of 24 IFN+AraC-treated patients crossed over to imatinib. Once imatinib commenced, the median BCR-ABL/BCR% levels in these patients were not significantly different to those on first-line imatinib for the equivalent number of months. The incidence of progression in imatinib-treated patients, defined by hematologic, cytogenetic or quantitative PCR criteria, was significantly higher in the patients who failed to achieve a 1 log reduction by 3 months or a 2 log reduction by 6 months, P=0.002. A total of 49 patients were screened for BCR-ABL kinase domain mutations. Mutations were detected in two imatinib-treated patients who crossed over from IFN+AraC and both lost their imatinib response. In conclusion, first-line imatinib-treated patients had profound reductions in BCR-ABL/BCR%, which significantly exceeded those of IFN+AraC-treated patients and early measurements were predictive of subsequent response.

Galactomannan and PCR versus culture and histology for directing use of antifungal treatment for invasive aspergillosis in high-risk haematology patients: a randomised controlled trial

BACKGROUND Empirical treatment with antifungal drugs is often used in haematology patients at high risk of invasive aspergillosis. We compared a standard diagnostic strategy (culture and histology) with a rapid biomarker-based diagnostic strategy (aspergillus galactomannan and PCR) for directing the use of antifungal treatment in this group of patients. METHODS In this open-label, parallel-group, randomised controlled trial, eligible patients were adults undergoing allogeneic stem-cell transplantation or chemotherapy for acute leukaemia, with no history of invasive fungal disease. Enrolled patients were randomly assigned (1:1) by a computer-generated schedule to follow either a standard diagnostic strategy (based on culture and histology) or a biomarker-based diagnostic strategy (aspergillus galactomannan and PCR) to direct treatment with antifungal drugs. Patients, were followed up for 26 weeks or until death. Masking of the use of different diagnostic tests was not possible for patients, treating physicians, or investigators. The primary endpoint was empirical treatment with antifungal drugs in the 26 weeks after enrolment (for the biomarker-based diagnostic strategy, a single postive galactomannan or PCR result was deemed insufficient to confirm invasive aspergillosis, so treatment in this context was classified as empirical). This outcome was assessed by an independent data review committee from which the study allocations were masked. Analyses were by intention to treat and included all enrolled patients. This study is registered with ClinicalTrial.gov, number NCT00163722. FINDINGS 240 eligible patients were recruited from six Australian centres between Sept 30, 2005, and Nov 19, 2009. 122 were assigned the standard diagnostic strategy and 118 the biomarker-based diagnostic strategy. 39 patients (32%) in the standard diagnosis group and 18 (15%) in the biomarker diagnosis group received empirical antifungal treatment (difference 17%, 95% CI 4-26; p=0·002). The numbers of patients who had hepatotoxic and nephrotoxic effects did not differ significantly between the standard diagnosis and biomarker diagnosis groups (hepatotoxic effects: 21 [17%] vs 12 [10%], p=0·11; nephrotoxic effects: 52 [43%] vs 60 [51%], p=0·20). INTERPRETATION Use of aspergillus galactomannan and PCR to direct treatment reduced use of empirical antifungal treatment. This approach is an effective strategy for the management of invasive aspergillosis in high-risk haematology patients. FUNDING Australian National Health and Medical Research Council, Cancer Council New South Wales, Pfizer, Merck, Gilead Sciences.

Outcome of treatment after first relapse in adults with acute lymphoblastic leukemia initially treated by the LALA-94 trial.

Fifty-four percent of adults with acute lymphoblastic leukemia (ALL) who entered the LALA-94 trial experienced a first relapse. We examined the outcome of these 421 adult patients. One hundred and eighty-seven patients (44%) achieved a second complete remission (CR). The median disease-free survival (DFS) was 5.2 months with a 5-year DFS at 12%. Factors predicting a better outcome after relapse were any transplant performed in second CR (P<0.0001), a first CR duration >1 year (P=0.04) and platelet level >100 × 109/l at relapse (P=0.04). Risk groups defined at diagnosis and treatment received in first CR did not influence the outcome after relapse. The best results were obtained in a subset of patients who were eligible for allogeneic stem cell transplantation (SCT). Geno-identical allogeneic SCT was performed in 55 patients, and 3 patients received donor lymphocyte infusions. Forty-four transplantations were performed from an unrelated donor (of which four were cord blood). We conclude that most adult patients with recurring ALL could not be rescued using current available therapies, although allogeneic SCT remains the best therapeutic option.

Rituximab versus a watch-and-wait approach in patients with advanced- stage, asymptomatic, non-bulky follicular lymphoma: an open-label randomised phase 3 trial

BACKGROUND Patients with advanced-stage, low-tumour-burden follicular lymphoma have conventionally undergone watchful waiting until disease progression. We assessed whether rituximab use could delay the need for chemotherapy or radiotherapy compared with watchful waiting and the effect of this strategy on quality of life (QoL). METHODS Asymptomatic patients (aged ≥18 years) with low-tumour-burden follicular lymphoma (grades 1, 2, and 3a) were randomly assigned centrally (1:1:1), by the minimisation approach stratified by institution, grade, stage, and age, to watchful waiting, rituximab 375 mg/m(2) weekly for 4 weeks (rituximab induction), or rituximab induction followed by a maintenance schedule of 12 further infusions given at 2-monthly intervals for 2 years (maintenance rituximab). On Sept 30, 2007, recruitment into the rituximab induction group was closed and the study was amended to a two-arm study. The primary endpoints were time to start of new treatment and QoL at month 7 (ie, 6 months after completion of rituximab induction). All randomly assigned patients were included in the analysis of time to start of new treatment on an intention-to-treat basis. The main study is now completed and is in long-term follow-up. The study is registered with ClinicalTrials.gov, NCT00112931. FINDINGS Between Oct 15, 2004, and March 25, 2009, 379 patients from 118 centres in the UK, Australia, New Zealand, Turkey, and Poland were randomly assigned to watchful waiting or maintenance rituximab. 84 patients were recruited to the rituximab induction group before it was closed early. There was a significant difference in the time to start of new treatment, with 46% (95% CI 39-53) of patients in the watchful waiting group not needing treatment at 3 years compared with 88% (83-92) in the maintenance rituximab group (hazard ratio [HR] 0·21, 95% CI 0·14-0·31; p<0·0001). 78% (95% CI 69-87) of patients in the rituximab induction group did not need treatment at 3 years, which was significantly more than in the watchful waiting group (HR 0·35, 95% CI 0·22-0·56; p<0·0001), but no different compared with the maintenance rituximab group (0·75, 0·41-1·34; p=0·33). Compared with the watchful waiting group, patients in the maintenance rituximab group had significant improvements in the Mental Adjustment to Cancer scale score (p=0·0004), and Illness Coping Style score (p=0·0012) between baseline and month 7. Patients in the rituximab induction group did not show improvements in their QoL compared with the watchful waiting group. There were 18 serious adverse events reported in the rituximab groups (four in the rituximab induction group and 14 in the maintenance rituximab group), 12 of which were grade 3 or 4 (five infections, three allergic reactions, and four cases of neutropenia), all of which fully resolved. INTERPRETATION Rituximab monotherapy should be considered as a treatment option for patients with asymptomatic, advanced-stage, low-tumour-burden follicular lymphoma. FUNDING Cancer Research UK, Lymphoma Research Trust, Lymphoma Association, and Roche.

Manufacturing of human placenta-derived mesenchymal stem cells for clinical trials.

Mesenchymal stem cells (MSC) are being used increasingly in clinical trials for a range of regenerative and inflammatory diseases. Bone marrow is the traditional source but is relatively inaccessible in large volume. MSC have now been derived from tissues other than bone marrow including placenta and adipose tissue. We have used placenta obtained after delivery as a source of MSC and have been unable to detect any marked differences from marrow‐derived MSC in terms of cell surface phenotype, chemokine receptor display, mesodermal differentiation capacity or immunosuppressive ability. This report described our manufacturing process for isolating and expanding placenta‐derived human MSC and their safe infusion into the first patient in a clinical trial program of human placenta‐derived MSC.

Activation of Wnt/β-catenin pathway mediates growth and survival in B-cell progenitor acute lymphoblastic leukaemia

This study investigated the response of acute lymphoblastic leukaemia (ALL) cells to Wnt proteins. Accumulation of β‐catenin was measured by Western blotting and immunofluorescence microscopy. Reverse transcription polymerase chain reaction (RT‐PCR) analysis of B‐cell progenitor acute lymphoblastic leukaemia (ALL) cells revealed expression of Wnt genes, including WNT2B in 33%, WNT5A in 42%, WNT10B in 58% and WNT16B in 25% of cases. The Wnt receptors, (Frizzled) FZD7 and FZD8 were also expressed in most cases while FZD3, FZD4 and FZD9 were occasionally detected. Stimulation of ALL cells with Wnt‐3a activated canonical Wnt signalling with increased expression and nuclear translocation of β‐catenin. This resulted in a 1·7‐ to 5·3‐fold increase in cell proliferation, which was associated with enhanced cell cycle entry. A significant increase in the survival of ALL cells under conditions of serum deprivation was also observed. Microarray analysis and quantitative RT‐PCR revealed that activation of the Wnt/β‐catenin pathway led to altered expression of genes involved in cell cycle regulation and apoptosis in normal and leukaemic B‐cell progenitors. Our results demonstrate that Wnt‐3a provides proliferative and survival cues in ALL cells. This data suggests that targeting the Wnt signalling pathway may be a useful therapeutic strategy in ALL.