Summary Background Gemtuzumab ozogamicin was the first example of antibody-directed chemotherapy in cancer, and was developed for acute myeloid leukaemia. However, randomised trials in which it was ...combined with standard induction chemotherapy in adults have produced conflicting results. We did a meta-analysis of individual patient data to assess the efficacy of adding gemtuzumab ozogamicin to induction chemotherapy in adult patients with acute myeloid leukaemia. Methods We searched PubMed for reports of randomised controlled trials published in any language up to May 1, 2013, that included an assessment of gemtuzumab ozogamicin given to adults (aged 15 years and older) in conjunction with the first course of intensive induction chemotherapy for acute myeloid leukaemia (excluding acute promyelocytic leukaemia) compared with chemotherapy alone. Published data were supplemented with additional data obtained by contacting individual trialists. The primary endpoint of interest was overall survival. We used standard meta-analytic techniques, with an assumption-free (or fixed-effect) method. We also did exploratory stratified analyses to investigate whether any baseline features predicted a greater or lesser benefit from gemtuzumab ozogamicin. Findings We obtained data from five randomised controlled trials (3325 patients); all trials were centrally randomised and open label, with overall survival as the primary endpoint. The addition of gemtuzumab ozogamicin did not increase the proportion of patients achieving complete remission with or without complete peripheral count recovery (odds ratio OR 0·91, 95% CI 0·77–1·07; p=0·3). However, the addition of gemtuzumab ozogamicin significantly reduced the risk of relapse (OR 0·81, 0·73–0·90; p=0·0001), and improved overall survival at 5 years (OR 0·90, 0·82–0·98; p=0·01). At 6 years, the absolute survival benefit was especially apparent in patients with favourable cytogenetic characteristics (20·7%; OR 0·47, 0·31–0·73; p=0·0006), but was also seen in those with intermediate characteristics (5·7%; OR 0·84, 0·75–0·95; p=0·005). Patients with adverse cytogenetic characteristics did not benefit (2·2%; OR 0·99, 0·83–1·18; p=0·9). Doses of 3 mg/m2 were associated with fewer early deaths than doses of 6 mg/m2 , with equal efficacy. Interpretation Gemtuzumab ozogamicin can be safely added to conventional induction therapy and provides a significant survival benefit for patients without adverse cytogenetic characteristics. These data suggest that the use of gemtuzumab ozogamicin should be reassessed and its licence status might need to be reviewed. Funding None.
Summary Background No randomised study has shown whether stratification of treatment by minimal residual disease (MRD) response improves outcome in children and young people with acute lymphoblastic ...leukaemia (ALL). We assessed whether children and young people with clinical standard and intermediate-risk ALL who have persistent MRD at the end of induction therapy benefit from augmented post-remission therapy. Methods Between Oct 1, 2003, and June 30, 2011, we enrolled eligible patients aged 1–24 years and initially categorised them into clinical standard-risk, intermediate-risk, and high-risk groups on the basis of a combination of National Cancer Institute criteria, cytogenetics, and early morphological response to induction therapy. Clinical standard-risk and intermediate-risk patients with MRD of 0·01% or higher at day 29 of induction (MRD high risk) were randomly assigned (1:1) to standard therapy (treatment regimens A and B) or augmented post-remission therapy (regimen C). Compared with standard therapy, the augmented treatment regimen (regimen C) included an additional eight doses of pegylated asparaginase, 18 doses of vincristine, and escalated-dose intravenous methotrexate without folinic acid rescue during interim maintenance courses. Computer randomisation was used for treatment allocation and was balanced for sex, age (<10 years vs ≥10 years), and white blood cell count at diagnosis (<50 × 109 /L vs ≥50 × 109 /L) by minimisation. Patients, clinicians, and data analysts were not masked to treatment allocation. The primary outcomes were event-free survival and overall survival. Analyses were by intention to treat. This trial is registered with Current Controlled Trials, number ISRCTN07355119. Findings 533 MRD high-risk patients were randomly assigned to receive standard (n=266) or augmented (n=267) post-remission therapy. After a median follow-up of 70 months (IQR 52–91), 5-year event-free survival was better in the augmented treatment group (89·6% 95% CI 85·9–93·3) than in the standard group (82·8% 78·1–87·5; odds ratio OR 0·61 95% CI 0·39–0·98, p=0·04). Overall survival at 5 years was numerically, but not significantly, higher in the augmented treatment group (92·9% 95% CI 89·8–96·0) than in the standard therapy group (88·9% 85·0–92·8; OR 0·67 95% CI 0·38–1·17, p=0·16). More adverse events occurred in the augmented treatment group than in the standard group (asparaginase-related hypersensitivity in 18 6·7% in the augmented group vs two 0·8% in the standard group and asparaginase-related pancreatitis in eight 3·0% vs one 0·4%; intravenous methotrexate-related mucositis in 11 4·1% vs three 1·1% and methotrexate-related stomatitis in 48 18·0% vs 12 4·5%). Interpretation Our findings suggest that children and young people with acute lymphoblastic leukaemia and 0·01% or more MRD at the end of remission induction therapy could benefit from augmented post-remission therapy. However, the asparaginase and intravenous methotrexate used in the augmented treatment regimen is associated with more adverse events than is the standard post-remission treatment regimen. Funding Medical Research Council and Leukaemia and Lymphoma Research.
Summary Background Chromosomal abnormalities in childhood acute lymphoblastic leukaemia are well established disease markers and indicators of outcomes. However, the long-term prognosis and ...independent prognostic effect of some abnormalities has been questioned. Also, little is known about the association between cytogenetics and the characteristics of relapse (eg, time and site of relapse) that are known to predict outcome after relapse. Methods We analysed cytogenetic data from 1725 children with B-cell precursor acute lymphoblastic leukaemia who were included in the UK Medical Research Council ALL97/99 study and followed up for a median time of 8·2 years. Univariate and multivariate analysis were done to examine risk of relapse, event-free survival, and overall survival associated with 21 chromosomal abnormalities and three cytogenetic risk groups constructed from these data. Findings Two chromosomal abnormalities were associated with a significantly better outcome ( ETV6–RUNX1 , hazard ratio HR 0·51, 95% CI 0·38–0·70 and high hyperdiploidy, 0·60, 0·47–0·78), whereas five abnormalities were associated with an increased risk of relapse (intrachromosomal amplification of chromosome 21 iAMP21, 6·04, 3·90–9·35; t(9;22), 3·55, 2·21–5·72; MLL translocations, 2·98, 1·71–5·20; abnormal 17p, 2·09, 1·30–3·37; and loss of 13q, 1·87, 1·09–3·20). Multivariate analysis incorporating age, white-cell count, and treatment parameters showed that six cytogenetic abnormalities ( ETV6–RUNX1 , high hyperdiploidy, iAMP21, t(9;22), loss of 13q, and abnormal 17p) retained their significance for effect on relapse risk. Based on these data, patients were classified into good, intermediate, and poor cytogenetic risk groups. Slow early treatment response correlated with cytogenetic risk group: 34 of 460 (7%) in the good-risk group, 22 of 211 (10%) in the intermediate-risk group, and 27 of 95 (28%) in the poor-risk group had a slow response (p<0·0001). Additionally, the proportion of patients with a very early (<18 months) relapse varied by cytogenetic risk group: eight of 129 (6%) patients in the good-risk group had a very early relapse, compared with 24 of 98 (24%) in the intermediate-risk group, and 37 of 82 (45%) in the poor-risk group (p<0·0001). However, there was no difference in the site of relapse by cytogenetic risk group. Interpretation Individual chromosomal abnormalities are strong independent indicators of outcome, especially risk of relapse. Diagnostic cytogenetics identifies patients with a higher rate of relapse and those who are likely to have a high-risk relapse. Funding Leukaemia and Lymphoma Research (LLR).
Summary Background Although survival of children with acute lymphoblastic leukaemia has improved greatly in the past two decades, the outcome of those who relapse has remained static. We investigated ...the outcome of children with acute lymphoblastic leukaemia who relapsed on present therapeutic regimens. Methods This open-label randomised trial was undertaken in 22 centres in the UK and Ireland and nine in Australia and New Zealand. Patients aged 1–18 years with first relapse of acute lymphoblastic leukaemia were stratified into high-risk, intermediate-risk, and standard-risk groups on the basis of duration of first complete remission, site of relapse, and immunophenotype. All patients were allocated to receive either idarubicin or mitoxantrone in induction by stratified concealed randomisation. Neither patients nor those giving interventions were masked. After three blocks of therapy, all high-risk group patients and those from the intermediate group with postinduction high minimal residual disease (≥10−4 cells) received an allogenic stem-cell transplant. Standard-risk and intermediate-risk patients with postinduction low minimal residual disease (<10−4 cells) continued chemotherapy. The primary outcome was progression-free survival and the method of analysis was intention-to-treat. Randomisation was stopped in December, 2007 because of differences in progression-free and overall survival between the two groups. This trial is registered, reference number ISCRTN45724312. Findings Of 239 registered patients, 216 were randomly assigned to either idarubicin (109 analysed) or mitoxantrone (103 analysed). Estimated 3-year progression-free survival was 35·9% (95% CI 25·9–45·9) in the idarubicin group versus 64·6% (54·2–73·2) in the mitoxantrone group (p=0·0004), and 3-year overall survival was 45·2% (34·5–55·3) versus 69·0% (58·5–77·3; p=0·004). Differences in progression-free survival between groups were mainly related to a decrease in disease events (progression, second relapse, disease-related deaths; HR 0·56, 0·34–0·92, p=0·007) rather than an increase in adverse treatment effects (treatment death, second malignancy; HR 0·52, 0·24–1·11, p=0·11). Interpretation As compared with idarubicin, mitoxantrone conferred a significant benefit in progression-free and overall survival in children with relapsed acute lymphobastic leukaemia, a potentially useful clinical finding that warrants further investigation. Funding Cancer Research UK, Leukaemia and Lymphoma Research, Cancer Council NSW, and Sporting Chance Cancer Foundation.