title: Estimating Long-Term Survival of Adults with Philadelphia Chromosome-Negative Relapsed/Refractory B-Precursor Acute Lymphoblastic Leukemia Treated with Blinatumomab Using Historical Data.
abstract: Blinatumomab is a bispecific T cell-engaging antibody construct indicated for adult patients with relapsed/refractory (R/R) Ph(-) B-precursor acute lymphoblastic leukemia (ALL), an aggressive disease with poor prognosis. A phase 2 single-arm clinical study showed that 43% of patients achieved CR/CRh within two cycles and approximately 20% of patients receiving blinatumomab were still alive after 2 years.
  
  
  
  The objective of the current analysis was to estimate long-term survival of patients receiving blinatumomab beyond the observed time period in the clinical study using a large historical observational dataset. Conditional survival probabilities of blinatumomab-treated patients beyond month 60 were assumed to be the same as the US general population.
  
  
  
  At month 60, the estimated proportion of blinatumomab-treated patients alive was more than double that of historical patients (12.6% vs 5.4%). The mean overall survival was 76.1 months for blinatumomab patients and 39.8 months for historical patients. Sensitivity analyses including additional follow-up data from the clinical study showed consistent results.
  
  
  
  These findings suggest that blinatumomab provides substantial overall survival benefit to patients with (R/R) Ph(-) B-precursor ALL compared with salvage chemotherapy.
  
  
  
  Amgen.
  
  
  
  ClinicalTrials.gov identifier NCT01466179 and NCT02003612.
authors.affiliation: Global Health Economics, Amgen Inc., Thousand Oaks, CA, USA.
authors.forename: Arie
authors.initials: A
authors.lastname: Barlev
authors.affiliation: Global Health Economics, Amgen Inc., Thousand Oaks, CA, USA.
authors.forename: Vincent W
authors.initials: VW
authors.lastname: Lin
authors.affiliation: Center for Observational Research, Amgen Inc., Thousand Oaks, CA, USA.
authors.forename: Aaron
authors.initials: A
authors.lastname: Katz
authors.affiliation: Global Biostatistical Science, Amgen Inc., Thousand Oaks, CA, USA.
authors.forename: Kuolung
authors.initials: K
authors.lastname: Hu
authors.affiliation: Global Health Economics, Amgen Inc., Thousand Oaks, CA, USA. zcong@amgen.com.
authors.forename: Ze
authors.initials: Z
authors.lastname: Cong
authors.affiliation: Global Health Economics, Amgen Inc., Thousand Oaks, CA, USA.
authors.forename: Beth
authors.initials: B
authors.lastname: Barber
mesh_terms: D018033:Antibodies, Bispecific / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D010677:Philadelphia Chromosome; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy* / Q000235:genetics / Q000401:mortality*; D012008:Recurrence; D012189:Retrospective Studies
chemical_list: D018033:Antibodies, Bispecific; D000970:Antineoplastic Agents; C510808:blinatumomab
keywords: Acute lymphoblastic leukemia; Blinatumomab; Hematology; Long-term survival; Oncology