Long-term follow-up of hematological relapse-free survival in a phase 2 study of blinatumomab in patients with minimal residual disease (MRD) of B-precursor acute lymphoblastic leukemia (ALL).

Department II, Universitaetsklinikum Wuerzburg, Wuerzburg, Germany
Blood (Impact Factor: 10.45). 09/2012; 120. DOI: 10.1182/blood-2012-07-441030
Source: PubMed


Persistence or recurrence of minimal residual disease (MRD) after chemotherapy results in clinical relapse in patients with acute lymphoblastic leukemia (ALL). In a phase II trial in B-lineage ALL patients with persistent or relapsed MRD, a T-cell engaging bispecific antibody construct, induced an 80% MRD response rate. In this report, we show that after a median follow up of 33 months the hematological relapse free survival (RFS) of the whole evaluable study cohort of 20 patients is 61% (Kaplan-Meier estimate). The hematological RFS rate of a subgroup of 9 patients, who received allogeneic hematopoietic stem cell transplantation (HSCT) after blinatumomab treatment, was 65% (Kaplan-Meier estimate). In the subgroup of 6 Ph - negative MRD responders with no further therapy after blinatumomab, 4 are in ongoing hematologic and molecular remission. Blinatumomab can induce long-lasting CRs in B-lineage ALL patients with persistent or recurrent MRD. (ClinicalTrials.gov identifier: NCT00198991, NCT00198978).

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