{"entity":{"id":"aall1331","kind":"trial","name":"AALL1331","aka":["COG AALL1331"],"tldr":"AALL1331 tested swapping blocks of harsh chemotherapy for the antibody blinatumomab in children whose leukaemia had come back; the antibody caused far fewer serious infections, more patients survived in the higher-risk group, and children whose relapse was in the bone marrow did better in the low-risk group too.","summary":"AALL1331 was a Children's Oncology Group phase 3 trial at 155 hospitals in the United States, Canada, Australia and New Zealand. All 669 patients received a four-week reinduction block and were then stratified. High- and intermediate-risk patients were randomised to two cycles of blinatumomab or two cycles of multi-agent chemotherapy, each followed by transplant. Low-risk patients were randomised to standard chemotherapy or chemotherapy with three blinatumomab blocks in place of some chemotherapy cycles. The primary endpoint in each stratum was disease-free survival.\n\nIn the high- and intermediate-risk randomisation, closed early on the monitoring committee's advice, two-year disease-free survival was 54.4 percent with blinatumomab against 39.0 percent with chemotherapy, a difference that did not reach the trial's threshold, while two-year overall survival was 71.3 against 58.4 percent and serious infections, sepsis and mucositis were far less common with blinatumomab. In the low-risk stratum the overall difference was not significant, but the two thirds of patients whose relapse involved the bone marrow had better disease-free and overall survival with blinatumomab, and the authors describe that as a new standard for them.","status":"mixed","asOf":"2026-09-22","links":[{"label":"ClinicalTrials.gov NCT02101853","url":"https://clinicaltrials.gov/study/NCT02101853"}],"tags":["soc-trials"],"related":[],"cancers":["all-paediatric-relapsed","all-leukemia","leukaemia"],"sections":[],"technologies":["t-cell-engager","bispecific-antibody"],"targets":[],"drugs":["blinatumomab"],"companies":[],"institutions":["childrens-oncology-group"],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":["paper-aall1331-brown-jama-2021","paper-aall1331-low-risk-hogan-jco-2023"],"journals":[],"dependsOn":[],"notes":[],"nct":"NCT02101853","phase":"3","setting":"Children, adolescents and young adults aged 1 to 30 with a first relapse of B-cell acute lymphoblastic leukaemia: after one block of reinduction chemotherapy, blinatumomab in place of intensive consolidation chemotherapy (high and intermediate risk, then transplant) or intercalated with chemotherapy (low risk)","sponsor":"National Cancer Institute (NCI)","result":"Blinatumomab consolidation gave two-year disease-free survival of 54.4 percent against 39.0 percent with chemotherapy in high- and intermediate-risk relapse (not statistically significant after early closure), with better overall survival and far less toxicity; in low-risk bone marrow relapse it improved disease-free and overall survival.","yearReported":2021,"enrolled":669,"enrolledBasis":"registry","outcomes":[{"endpoint":"Disease-free survival at 2 years, high- and intermediate-risk relapse","primary":true,"unit":"%","arms":[{"name":"Blinatumomab consolidation then transplant","n":105,"value":54.4},{"name":"Chemotherapy consolidation then transplant","n":103,"value":39}],"hr":0.7,"ci":[0.47,1.03],"p":"0.03 (one-sided)","source":"https://doi.org/10.1001/jama.2021.0669"},{"endpoint":"Overall survival at 2 years, high- and intermediate-risk relapse","unit":"%","arms":[{"name":"Blinatumomab consolidation then transplant","n":105,"value":71.3},{"name":"Chemotherapy consolidation then transplant","n":103,"value":58.4}],"hr":0.62,"ci":[0.39,0.98],"p":"0.02 (one-sided)","source":"https://doi.org/10.1001/jama.2021.0669"},{"endpoint":"Serious infection as an adverse event, high- and intermediate-risk relapse","unit":"%","arms":[{"name":"Blinatumomab consolidation then transplant","value":15},{"name":"Chemotherapy consolidation then transplant","value":65}],"source":"https://doi.org/10.1001/jama.2021.0669"},{"endpoint":"Disease-free survival at 4 years, low-risk relapse","primary":true,"unit":"%","arms":[{"name":"Chemotherapy with blinatumomab blocks","value":61.2},{"name":"Chemotherapy alone","value":49.5}],"p":"0.089","source":"https://doi.org/10.1200/jco.22.02200"},{"endpoint":"Overall survival at 4 years, low-risk relapse","unit":"%","arms":[{"name":"Chemotherapy with blinatumomab blocks","value":90.4},{"name":"Chemotherapy alone","value":79.6}],"p":"0.11","source":"https://doi.org/10.1200/jco.22.02200"},{"endpoint":"Disease-free survival at 4 years, low-risk relapse involving the bone marrow","unit":"%","arms":[{"name":"Chemotherapy with blinatumomab blocks","value":72.7,"note":"174 patients with marrow relapse across both arms"},{"name":"Chemotherapy alone","value":53.7}],"p":"0.015","source":"https://doi.org/10.1200/jco.22.02200"}]},"route":"/trials/aall1331/","neighbours":{"cancer":[{"id":"all-leukemia","kind":"cancer","name":"Acute lymphoblastic leukaemia","route":"/cancers/all-leukemia/"},{"id":"leukaemia","kind":"cancer","name":"Leukaemia (all types)","route":"/cancers/leukaemia/"},{"id":"all-paediatric-relapsed","kind":"cancer","name":"Relapsed and refractory acute lymphoblastic leukaemia in children","route":"/cancers/all-paediatric-relapsed/"}],"technology":[{"id":"bispecific-antibody","kind":"technology","name":"Bispecific antibodies","route":"/technologies/bispecific-antibody/"},{"id":"t-cell-engager","kind":"technology","name":"T-cell engagers (bispecific)","route":"/technologies/t-cell-engager/"}],"drug":[{"id":"blinatumomab","kind":"drug","name":"Blinatumomab","route":"/drugs/blinatumomab/"}],"institution":[{"id":"childrens-oncology-group","kind":"institution","name":"Children's Oncology Group (COG)","route":"/institutions/childrens-oncology-group/"}],"paper":[{"id":"paper-aall1331-low-risk-hogan-jco-2023","kind":"paper","name":"AALL1331: blinatumomab added to chemotherapy in low-risk first relapse of childhood B-ALL","route":"/key-papers/paper-aall1331-low-risk-hogan-jco-2023/"},{"id":"paper-aall1331-brown-jama-2021","kind":"paper","name":"AALL1331: blinatumomab versus chemotherapy consolidation in high- and intermediate-risk first relapse of childhood B-ALL","route":"/key-papers/paper-aall1331-brown-jama-2021/"}]}}