Compared with bendamustine plus rituximab, venetoclax plus rituximab more than doubled the 2-year progression-free survival (PFS) rate among patients with relapsed or refractory (R/R) chronic lymphocytic leukemia (CLL), according to a study published in The New England Journal of Medicine.1
For the open-label phase 3 MURANO study (ClinicalTrials.gov Identifier: NCT02005471), researchers randomly assigned 389 patients with R/R CLL to receive venetoclax for 2 years and rituximab for the first 6 months, or bendamustine plus rituximab for 6 months; participants were stratified according to chromosome 17p deletion status, response to previous therapy, and geographic region.
After a median follow-up of 23.8 months, patients in the venetoclax arm had an improved 2-year PFS rate, at 84.9% vs 36.3% in the bendamustine arm (hazard ratio for progression or death [HR], 0.17; 95% CI, 0.11-025; P < .001). This improvement was observed in all patient subgroups regardless of stratification.
Patients in the venetoclax arm had better outcomes compared with the bendamustine arm, including improved overall survival, event-free survival, and notably, minimal residual disease (MRD) — an important marker for long-term outcomes.
Patients in venetoclax arm had an increased rate of grade 3 or 4 neutropenia compared with those in the bendamustine arm, but had a lower rate of grade 3 or 4 febrile neutropenia and infections or infestations. Patients in the venetoclax arm had a grade 3 or 4 tumor lysis syndrome rate of 3.1%.
The authors concluded that “the substantial rate of clearance of minimal residual disease in the venetoclax–rituximab group may indicate improved disease control over a longer term even when therapy is discontinued. Additional follow-up will be needed to assess the durability of such responses.”
- Seymour JF, Kipps TJ, Eichhorst B, et al. Venetoclax-rituximab in relapsed or refractory chronic lymphocytic leukemia. N Engl J Med. 2018 Mar 22. doi: 10.1056/NEJMoa1713976 [Epub ahead of print]