John A. Liu Yin

Identification of patients with acute myeloblastic leukemia who benefit from the addition of gemtuzumab ozogamicin: Results of the MRC AML15 Trial

PURPOSE Antibody-directed chemotherapy for acute myeloid leukemia (AML) may permit more treatment to be administered without escalating toxicity. Gemtuzumab ozogamicin (GO) is an immunoconjugate between CD33 and calicheamicin that is internalized when binding to the epitope. We previously established that it is feasible to combine GO with conventional chemotherapy. We now report a large randomized trial testing the addition of GO to induction and/or consolidation chemotherapy in untreated younger patients. PATIENTS AND METHODS In this open-label trial, 1,113 patients, predominantly younger than age 60 years, were randomly assigned to receive a single dose of GO (3 mg/m(2)) on day 1 of induction course 1 with one of the following three induction schedules: daunorubicin and cytarabine; cytarabine, daunorubicin, and etoposide; or fludarabine, cytarabine, granulocyte colony-stimulating factor, and idarubicin. In remission, 948 patients were randomly assigned to GO in course 3 in combination with amsacrine, cytarabine, and etoposide or high-dose cytarabine. The primary end points were response rate and survival. RESULTS The addition of GO was well tolerated with no significant increase in toxicity. There was no overall difference in response or survival in either induction of consolidation. However, a predefined analysis by cytogenetics showed highly significant interaction with induction GO (P = .001), with significant survival benefit for patients with favorable cytogenetics, no benefit for patients with poor-risk disease, and a trend for benefit in intermediate-risk patients. An internally validated prognostic index identified approximately 70% of patients with a predicted benefit of 10% in 5-year survival. CONCLUSION A substantial proportion of younger patients with AML have improved survival with the addition of GO to induction chemotherapy with little additional toxicity.

Guidelines for the diagnosis and management of aplastic anaemia

King’s College Hospital, St Mary’s Hospital, Barts and The London Hospital, London, Birmingham Children’s Hospital, Birmingham, Barts and The London School of Medicine and Dentistry, St George’s Hospital, London, Queen Elizabeth Hospital, King’s Lynn, Norfolk, Ashford Hospital, Middlesex, London, Patient representative, St Helier Hospital, Carshalton, Surrey, Royal Bournemouth Hospital, Dorset, Chesterfield Royal Hospital, Derbyshire, and Manchester Royal Infirmary, Manchester, UK.

Addition of Gemtuzumab Ozogamicin to Induction Chemotherapy Improves Survival in Older Patients With Acute Myeloid Leukemia

PURPOSE There has been little survival improvement in older patients with acute myeloid leukemia (AML) in the last two decades. Improving induction treatment may improve the rate and quality of remission and consequently survival. In our previous trial, in younger patients, we showed improved survival for the majority of patients when adding gemtuzumab ozogamicin (GO) to induction chemotherapy. PATIENTS AND METHODS Untreated patients with AML or high-risk myelodysplastic syndrome (median age, 67 years; range, 51 to 84 years) were randomly assigned to receive induction chemotherapy with either daunorubicin/ara-C or daunorubicin/clofarabine, with (n = 559) or without (n = 556) GO 3 mg/m(2) on day 1 of course one of therapy. The primary end point was overall survival (OS). RESULTS The overall response rate was 69% (complete remission [CR], 60%; CR with incomplete recovery [CRi], 9%), with no difference between GO (70%) and no GO (68%) arms. There was no difference in 30- or 60-day mortality and no major increase in toxicity with GO. With median follow-up of 30 months (range, 5.5 to 54.6 months), 3-year cumulative incidence of relapse was significantly lower with GO (68% v 76%; hazard ratio [HR], 0.78; 95% CI, 0.66 to 0.93; P = .007), and 3-year survival was significantly better (25% v 20%; HR, 0.87; 95% CI, 0.76 to 1.00; P = .05). The benefit was apparent across subgroups. There was no interaction with other treatment interventions. A meta-analysis of 2,228 patients in two United Kingdom National Cancer Research Institute trials showed significant improvements in relapse (HR, 0.82; 95% CI, 0.72 to 0.93; P = .002) and OS (HR, 0.88; 95% CI, 0.79 to 0.98; P = .02). CONCLUSION Adding GO (3 mg/m(2)) to induction chemotherapy reduces relapse risk and improves survival with little increase in toxicity.

Azacitidine augments expansion of regulatory T cells after allogeneic stem cell transplantation in patients with acute myeloid leukemia (AML)

Strategies that augment a GVL effect without increasing the risk of GVHD are required to improve the outcome after allogeneic stem cell transplantation (SCT). Azacitidine (AZA) up-regulates the expression of tumor Ags on leukemic blasts in vitro and expands the numbers of immunomodulatory T regulatory cells (Tregs) in animal models. Reasoning that AZA might selectively augment a GVL effect, we studied the immunologic sequelae of AZA administration after allogeneic SCT. Twenty-seven patients who had undergone a reduced intensity allogeneic transplantation for acute myeloid leukemia were treated with monthly courses of AZA, and CD8(+) T-cell responses to candidate tumor Ags and circulating Tregs were measured. AZA after transplantation was well tolerated, and its administration was associated with a low incidence of GVHD. Administration of AZA increased the number of Tregs within the first 3 months after transplantation compared with a control population (P = .0127). AZA administration also induced a cytotoxic CD8(+) T-cell response to several tumor Ags, including melanoma-associated Ag 1, B melanoma antigen 1, and Wilm tumor Ag 1. These data support the further examination of AZA after transplantation as a mechanism of augmenting a GVL effect without a concomitant increase in GVHD.

Minimal residual disease monitoring by quantitative RT-PCR in core binding factor AML allows risk stratification and predicts relapse: results of the United Kingdom MRC AML-15 trial.

The clinical value of serial minimal residual disease (MRD) monitoring in core binding factor (CBF) acute myeloid leukemia (AML) by quantitative RT-PCR was prospectively assessed in 278 patients [163 with t(8;21) and 115 with inv(16)] entered in the United Kingdom MRC AML 15 trial. CBF transcripts were normalized to 10(5) ABL copies. At remission, after course 1 induction chemotherapy, a > 3 log reduction in RUNX1-RUNX1T1 transcripts in BM in t(8;21) patients and a > 10 CBFB-MYH11 copy number in peripheral blood (PB) in inv(16) patients were the most useful prognostic variables for relapse risk on multivariate analysis. MRD levels after consolidation (course 3) were also informative. During follow-up, cut-off MRD thresholds in BM and PB associated with a 100% relapse rate were identified: for t(8;21) patients BM > 500 copies, PB > 100 copies; for inv(16) patients, BM > 50 copies and PB > 10 copies. Rising MRD levels on serial monitoring accurately predicted hematologic relapse. During follow-up, PB sampling was equally informative as BM for MRD detection. We conclude that MRD monitoring by quantitative RT-PCR at specific time points in CBF AML allows identification of patients at high risk of relapse and could now be incorporated in clinical trials to evaluate the role of risk directed/preemptive therapy.

European development of clofarabine as treatment for older patients with acute myeloid leukemia considered unsuitable for intensive chemotherapy.

PURPOSE Treatment options for older patients with acute myeloid leukemia (AML) who are not considered suitable for intensive chemotherapy are limited. We assessed the second-generation purine nucleoside analog, clofarabine, in two similar phase II studies in this group of patients. PATIENTS AND METHODS Two consecutive studies, UWCM-001 and BIOV-121, recruited untreated older patients with AML to receive up to four or six 5-day courses of clofarabine. Patients in UWCM-001 were either older than 70 years or 60 to 69 years of age with poor performance status (WHO > 2) or with cardiac comorbidity. Patients in BIOV-121 were >or= 65 years of age and deemed unsuitable for intensive chemotherapy. RESULTS A total of 106 patients were treated in the two monotherapy studies. Median age was 71 years (range, 60 to 84 years), 30% had adverse-risk cytogenetics, and 36% had a WHO performance score >or= 2. Forty-eight percent had a complete response (32% complete remission, 16% complete remission with incomplete peripheral blood count recovery), and 18% died within 30 days. Interestingly, response and overall survival were not inferior in the adverse cytogenetic risk group. The safety profile of clofarabine in these elderly patients with AML who were unsuitable for intensive chemotherapy was manageable and typical of a cytotoxic agent in patients with acute leukemia. Patients had similar prognostic characteristics to matched patients treated with low-dose cytarabine in the United Kingdom AML14 trial, but had significantly superior response and overall survival. CONCLUSION Clofarabine is active and generally well tolerated in this patient group. It is worthy of further evaluation in comparative trials and might be of particular use in patients with adverse cytogenetics.

Guidelines for the diagnosis and management of acquired aplastic anaemia.

The purpose of this guideline is to provide a rational approach to the investigation and management of patients with acquired aplastic anaemia. These guidelines have been produced by both specialists in the field of aplastic anaemia and experienced district general hospital haematologists, and reviewed by members of the British Committee for Standards in Haematology (BCSH) General Haematology Task Force. Because aplastic anaemia is a rare disease, many of the statements and comments in the first part of this manuscript are based on review of the literature and expert or consensus opinion rather than on clinical studies or trials. Medline, Cinahl and Embase databases were searched for this purpose. Levels of evidence for treatment of aplastic anaemia also reflect the rarity of this condition. To ensure wide dissemination of these guidelines, they are also available on the BCSH website and will be reviewed on a three yearly basis.

Five new pedigrees with inherited RUNX1 mutations causing familial platelet disorder with propensity to myeloid malignancy

Familial platelet disorder with propensity to myeloid malignancy (FPD/AML) is an autosomal dominant syndrome characterized by platelet abnormalities and a predisposition to myelodysplasia (MDS) and/or acute myeloid leukemia (AML). The disorder, caused by inherited mutations in RUNX1, is uncommon with only 14 pedigrees reported. We screened 10 families with a history of more than one first degree relative with MDS/AML for inherited mutations in RUNX1. Germ- line RUNX1 mutations were identified in 5 pedigrees with a 3:2 predominance of N-terminal mutations. Several affected members had normal platelet counts or platelet function, features not previously reported in FPD/AML. The median incidence of MDS/AML among carriers of RUNX1 mutation was 35%. Individual treatments varied but included hematopoietic stem cell transplantation from siblings before recognition of the inherited leukemogenic mutation. Transplantation was associated with a high incidence of complications including early relapse, failure of engraftment, and posttransplantation lymphoproliferative disorder. Given the small size of modern families and the clinical heterogeneity of this syndrome, the diagnosis of FPD/AML could be easily overlooked and may be more prevalent than previously recognized. Therefore, it would appear prudent to screen young patients with MDS/AML for RUNX1 mutation, before consideration of sibling hematopoietic stem cell transplantation.

Curability of Patients With Acute Myeloid Leukemia Who Did Not Undergo Transplantation in First Remission

PURPOSE The aims of this study were to quantify the prospects of salvage treatment of patients who did not undergo transplantation in first complete remission (CR1) and to assess the contribution of allograft in second complete remission (CR2) with respect to major risk groups. This evaluation can inform the decision whether to offer a transplant in CR1. PATIENTS AND METHODS Of 8,909 patients who entered the Medical Research Council AML10, AML12, and AML15 trials, 1,271 of 3,919 patients age 16 to 49 years who did not receive a transplant in CR1 relapsed. Of these patients, 19% are alive beyond 5 years compared with 7% of patients who relapsed after an allograft in CR1. Overall survival and the contribution of a transplant in CR2 were assessed overall and by cytogenetic risk group by using Mantel-Byar analysis. RESULTS Fifty-five percent of patients who relapsed entered CR2. This percentage varied by risk group as follows: favorable (82%), intermediate (54%), adverse (27%), and unknown (53%), which resulted in 5-year survivals of 32%, 17%, 7%, and 23%, respectively. Sixty-seven percent of remitters received an allotransplant that delivered superior survival compared with patients who did not receive a stem-cell transplant (42% v 16%). A more-stringent assessment of a transplant by using delayed-entry (Mantel-Byar) analysis confirmed the benefit of transplant overall and within intermediate and adverse risk groups but not the favorable subgroup. CONCLUSION Successful salvage treatment of patients who do not undergo transplantation in CR1 and relapse can be achieved in 19% of patients, which is improved by a transplant except in favorable risk disease. This result suggests that, for intermediate-risk patients in particular, equivalent overall survival can be achieved by delaying transplantation until after relapse, which would require many fewer transplants.

Overexpression of lung‐resistance protein and increased P‐glycoprotein function in acute myeloid leukaemia cells predict a poor response to chemotherapy and reduced patient survival

We investigated the role of the drug resistance‐related proteins LRP, MRP and Pgp and the apoptotic suppressor, bcl‐2, in relation to other clinical characteristics, with respect to response and survival in 91 patients with newly diagnosed AML, treated with standard chemotherapy. Multivariate analysis showed that poor response to chemotherapy was associated with increasing age (P = 0.0004), LRP expression (P = 0.0001) and Pgp function (P = 0.015). The significant predictors of both leukaemia‐free survival (LFS) and overall survival (OS) were LRP (LFS, P = 0.01; OS, P = 0.0001), Pgp function (LFS, P = 0.0001; OS, P = 0.0003) and cytogenetic abnormalities (LFS, P = 0.0001; OS, P = 0.0005). Patients with the lowest expression of LRP and Pgp function and favourable karyotype (group I) had an LFS of 30.2 months compared to 8.5 months in the group with the highest expression of LRP and Pgp and poor prognosis karyotype (group III, P = 0.002). OS decreased from 75.4 months in group I to 7.9 months in group III patients (P  < 0.0001). Neither MRP nor bcl‐2 were significantly associated with chemotherapy response and survival. Correlations were found between increasing expression of LRP and older age (P = 0.05) and an unfavourable karyotype (P = 0.005), but these variables were independent of each other in analysis of treatment response and patient survival. Our findings suggest that both LRP and Pgp are clinically relevant drug‐resistance proteins and it may be necessary to modulate both LRP and Pgp functions in order to reverse the multidrug resistance phenotype in AML.