Patients

IMMUNOSTIM is a sub-study of the STIM trial approved by French health authorities ({"type":"clinical-trial","attrs":{"text":"NCT00478985","term_id":"NCT00478985"}}NCT00478985).⁹ Written informed consent was given in agreement with the Declaration of Helsinki. Imatinib was stopped after ≥3 years of therapy and ≥2 years of undetectable BCR-ABL1 transcripts. Stringent monitoring by RT-qPCR was performed after imatinib discontinuation to detect a molecular relapse.⁹ The assay sensitivity was ≥4.5 log. Consecutively detectable peripheral blood BCR-ABL1 transcripts showing a ≥1 log increase or loss of a major molecular response [BCR-ABL1/ABL1 internationally standardized (IS) ratio ≤0.1%] defined molecular relapse and triggered imatinib resumption. In IMMUNOSTIM, heparinized blood was collected at baseline, bimonthly for 6 months then every 6 months until 24 months unless imatinib was resumed. Healthy donors were recruited through the Paris Saint-Louis Blood Donation Center and gave informed consent. Experiments were performed in a centralized fashion, allowing ≤48 h from blood collection to processing.