Fixed Duration of Venetoclax-Rituximab in Relapsed/Refractory Chronic Lymphocytic Leukemia Eradicates Minimal Residual Disease and Prolongs Survival: Post-Treatment Follow-Up of the MURANO Phase III Study

J Clin Oncol. 2019 Feb 1;37(4):269-277. doi: 10.1200/JCO.18.01580. Epub 2018 Dec 3.


Purpose: The MURANO study demonstrated significant progression-free survival (PFS) benefit for fixed-duration venetoclax-rituximab compared with bendamustine-rituximab in relapsed/refractory chronic lymphocytic leukemia. With all patients off treatment, we report minimal residual disease (MRD) kinetics and updated outcomes.

Methods: Patients were randomly assigned to 2 years of venetoclax plus rituximab during the first six cycles, or six cycles of bendamustine-rituximab. Primary end point was PFS. Safety and peripheral blood (PB) MRD status-at cycle 4, 2 to 3 months after end of combination therapy (EOCT), and every 3 to 6 months thereafter-were secondary end points.

Results: Of 194 patients, 174 (90%) completed the venetoclax-rituximab phase and 130 (67%) completed 2 years of venetoclax. With a median follow-up of 36 months, PFS and overall survival remain superior to bendamustine-rituximab (hazard ratio, 0.16 [95% CI, 0.12 to 0.23]; and hazard ratio, 0.50 [95% CI, 0.30 to 0.85], respectively). Patients who received venetoclax-rituximab achieved a higher rate of PB undetectable MRD (uMRD; less than 10-4) at EOCT (62% v 13%) with superiority sustained through month 24 (end of therapy). Overall, uMRD status at EOCT predicted longer PFS. Among those with detectable MRD, low-level MRD (10-4 to less than 10-2) predicted improved PFS compared with high-level MRD (10-2 or greater). At a median of 9.9 months (range, 1.4 to 22.5 months) after completing fixed-duration venetoclax-rituximab, overall only 12% (16 of 130) of patients developed disease progression (11 high-level MRD, three low-level MRD). At the end of therapy, 70% and 98% of patients with uMRD remained in uMRD and without disease progression, respectively.

Conclusion: With all patients having finished treatment, continued benefit was observed for venetoclax-rituximab compared with bendamustine-rituximab. uMRD rates were durable and predicted longer PFS, which establishes the impact of PB MRD on the benefit of fixed-duration, venetoclax-containing treatment. Low conversion to detectable MRD and sustained PFS after completion of 2 years of venetoclax-rituximab demonstrate the feasibility of this regimen.

Trial registration: NCT02005471.

Publication types

  • Clinical Trial, Phase III
  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Antineoplastic Combined Chemotherapy Protocols / adverse effects
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use*
  • Bendamustine Hydrochloride / administration & dosage*
  • Bendamustine Hydrochloride / adverse effects
  • Bridged Bicyclo Compounds, Heterocyclic / administration & dosage*
  • Bridged Bicyclo Compounds, Heterocyclic / adverse effects
  • Drug Administration Schedule
  • Drug Resistance, Neoplasm
  • Female
  • Humans
  • Leukemia, Lymphocytic, Chronic, B-Cell / drug therapy*
  • Leukemia, Lymphocytic, Chronic, B-Cell / mortality
  • Leukemia, Lymphocytic, Chronic, B-Cell / pathology
  • Male
  • Middle Aged
  • Neoplasm, Residual
  • Progression-Free Survival
  • Recurrence
  • Rituximab / administration & dosage*
  • Rituximab / adverse effects
  • Sulfonamides / administration & dosage*
  • Sulfonamides / adverse effects
  • Time Factors


  • Bridged Bicyclo Compounds, Heterocyclic
  • Sulfonamides
  • Rituximab
  • Bendamustine Hydrochloride
  • venetoclax

Associated data