ASCO20: Venetoclax Plus Obinutuzumab in Treatment-Naive CLL
Posted: Tuesday, June 23, 2020
During an extended follow-up of the phase III CLL14 trial, fixed-duration venetoclax plus obinutuzumab showed improved safety compared with chlorambucil plus obinutuzumab in patients with previously untreated chronic lymphocytic leukemia (CLL). The updated results were presented during the ASCO20 Virtual Scientific Program (Abstract 8027). Othman Al-Sawaf, MD, of the University of Cologne, Germany, and colleagues reported long-term benefits of 12 cycles of venetoclax plus obinutuzumab that were seen across all known risk categories.
For this multicenter, open-label, randomized study, a total of 432 patients were enrolled. They were randomly and evenly assigned to receive either 12 cycles of venetoclax with 6 cycles of obinutuzumab or 12 cycles of chlorambucil with 6 cycles of obinutuzumab. Investigator-assessed progression-free survival was the primary endpoint, and secondary endpoints included response rates and overall survival.
After a median follow-up of 39.6 months, progression-free survival was longer with venetoclax than chlorambucil (hazard ratio [HR] = 0.31; P < .001). The estimated progression-free survival rate at 3 years was 81.9% for patients with the venetoclax combination therapy and 49.5% with the chlorambucil combination therapy. In addition, the benefit with the venetoclax regimen was seen across all clinical and biologic risk groups, including those with TP53 mutation/deletion and unmutated IGHV status. In terms of overall survival, no difference between the groups was observed (HR = 1.027; P = .921). Median overall survival had not been reached in either group at the time of the presentation.
As for toxicity, no new safety signals emerged. Patients treated with venetoclax had more second primary malignancies than those treated with chlorambucil (17% vs. 10%).
Disclosure: For the full disclosures of the study authors, visit coi.asco.org.
