Sustained efficacy and detailed clinical follow-up of first-line ibrutinib treatment in older patients with chronic lymphocytic leukemia: extended phase 3 results from RESONATE-2

Haematologica. 2018 Sep;103(9):1502-1510. doi: 10.3324/haematol.2018.192328. Epub 2018 Jun 7.

Abstract

Results of RESONATE-2 (PCYC-1115/1116) supported approval of ibrutinib for first-line treatment of chronic lymphocytic leukemia. Extended analysis of RESONATE-2 was conducted to determine long-term efficacy and safety of ibrutinib in older patients with chronic lymphocytic leukemia. A total of 269 patients aged ≥65 years with previously untreated chronic lymphocytic leukemia without del(17p) were randomized 1:1 to ibrutinib (n=136) or chlorambucil (n=133) on days 1 and 15 of a 28-day cycle for 12 cycles. Median ibrutinib treatment duration was 28.5 months. Ibrutinib significantly prolonged progression-free survival versus chlorambucil (median, not reached vs 15 months; hazard ratio, 0.12; 95% confidence interval, 0.07-0.20; P<0.0001). The 24-month progression-free survival was 89% with ibrutinib (97% and 89% in patients with del[11q] and unmutated immunoglobulin heavy chain variable region gene, respectively). Progression-free survival rates at 24 months were also similar regardless of age (<75 years [88%], ≥75 years [89%]). Overall response rate was 92% (125/136). Rate of complete response increased substantially from 7% at 12 months to 18% with extended follow up. Greater quality of life improvements occurred with ibrutinib versus chlorambucil in Functional Assessment of Chronic Illness Therapy-Fatigue (P=0.0013). The most frequent grade ≥3 adverse events were neutropenia (12%), anemia (7%), and hypertension (5%). Rate of discontinuations due to adverse events was 12%. Results demonstrated that first-line ibrutinib for elderly patients with chronic lymphocytic leukemia provides sustained response and progression-free survival benefits over chemotherapy, with depth of response improving over time without new toxicity concerns. This trial was registered at clinicaltrials.gov identifier 01722487 and 01724346.

Trial registration: ClinicalTrials.gov NCT01722487 NCT01724346.

Publication types

  • Clinical Trial, Phase III
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Antineoplastic Agents / administration & dosage
  • Antineoplastic Agents / adverse effects
  • Antineoplastic Agents / therapeutic use*
  • Antineoplastic Combined Chemotherapy Protocols / adverse effects
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use
  • Biomarkers, Tumor
  • Female
  • Follow-Up Studies
  • Humans
  • Leukemia, Lymphocytic, Chronic, B-Cell / diagnosis
  • Leukemia, Lymphocytic, Chronic, B-Cell / drug therapy*
  • Leukemia, Lymphocytic, Chronic, B-Cell / genetics
  • Male
  • Molecular Targeted Therapy
  • Mutation
  • Neoplasm Staging
  • Prognosis
  • Protein Kinase Inhibitors / administration & dosage
  • Protein Kinase Inhibitors / adverse effects
  • Protein Kinase Inhibitors / therapeutic use*
  • Pyrazoles / administration & dosage
  • Pyrazoles / adverse effects
  • Pyrazoles / therapeutic use*
  • Pyrimidines / administration & dosage
  • Pyrimidines / adverse effects
  • Pyrimidines / therapeutic use*
  • Treatment Outcome

Substances

  • Antineoplastic Agents
  • Biomarkers, Tumor
  • Protein Kinase Inhibitors
  • Pyrazoles
  • Pyrimidines
  • ibrutinib

Associated data

  • ClinicalTrials.gov/NCT01722487
  • ClinicalTrials.gov/NCT01724346