The MURANO study: final analysis and retreatment/crossover substudy results of VenR for patients with relapsed/refractory CLL

• In the VenR arm, the 7-year PFS rate was 23% and OS rate was 70%; median time from PD after MRD conversion to next therapy was 5 months.

• In a substudy, 25 patients were retreated with VenR; median PFS was 23 months, ORR was 72%, and 32% achieved uMRD at retreatment EOCT.

Fixed-duration venetoclax-rituximab (VenR) in patients with relapsed/refractory chronic lymphocytic leukemia (CLL) in the phase 3 MURANO trial (NCT02005471) resulted in superior progression-free survival (PFS) and overall survival (OS) vs bendamustine-rituximab (BR). We report the final analyses of MURANO (median 7 years follow-up). Patients were randomized to VenR (venetoclax 400 mg daily for 2 years plus monthly rituximab for 6 months; n = 194) or BR (6 months; n = 195). In a substudy, patients with progressive disease (PD) received VenR as retreatment or crossover from BR. At the final data cut (3 August 2022), median PFS with VenR was 54.7 vs 17.0 months with BR. Seven-year PFS with VenR was 23.0%. Seven-year OS was 69.6% and 51.0%, respectively. Among VenR-treated patients with undetectable (u) minimal residual disease (MRD) and no PD at end of treatment (EOT) (n = 83), median PFS from EOT was 52.5 vs 18.0 months in patients with MRD at EOT (n = 35; P < 0.0001). Fourteen patients had enduring uMRD. Three distinct mutations in BCL2 in four patients were identified. In the substudy, 25 patients were retreated with VenR and nine patients crossed over to VenR; median PFS was 23 and 27 months, and best overall response rate was 72% and 89%, respectively. At the end of combination treatment, following retreatment or crossover, eight and six patients achieved uMRD, respectively. No new safety findings were observed. Overall, these final MURANO analyses support consideration of fixed-duration VenR therapy for patients with relapsed/refractory CLL.