CLL14 Trial of Venetoclax Plus Obinutuzumab: Update After 5 Years Off Treatment

By: Julia Fiederlein
Posted: Tuesday, July 26, 2022

In the phase III CLL14 trial, 1-year fixed-duration venetoclax plus obinutuzumab demonstrated improved progression-free survival compared with chlorambucil plus obinutuzumab in patients with previously untreated chronic lymphocytic leukemia (CLL) and coexisting conditions. The 5-year updated efficacy and safety data from an ongoing off-treatment follow-up analysis, which were presented by Othman Al-Sawaf, MD, of the University Hospital of Cologne, Germany, and colleagues during the European Hematology Association (EHA) 2022 Congress (Abstract S148), further supported this finding.

A total of 432 patients were randomly assigned in a 1:1 ratio to receive obinutuzumab in combination with either venetoclax or chlorambucil. Progression-free survival remained significantly superior with venetoclax versus chlorambucil at a median follow-up of 65.4 months (median, not reached vs. 36.4 months; P < .0001). The estimated 5-year progression-free survival rate was 62.6% with venetoclax and 27.0% with chlorambucil. Fewer patients required second-line treatment in the venetoclax arm (28 vs. 86). The 5-year time-to-next-treatment rate was 72.1% with venetoclax and 42.8% with chlorambucil (P < .0001). According to the investigators, the progression-free survival and the time-to-next-treatment difference were maintained across all risk groups.

Based on a multivariable analysis, 17p deletion and high disease burden were identified as independent prognostic factors for progression-free survival in patients treated with venetoclax. A total of 4 years after treatment completion, in the intention-to-treat population, the rates of undetectable, low, and high measurable residual disease were 18.1%, 12.5%, and 19.0% with venetoclax and 1.9%, 6.0%, and 11.1% with chlorambucil, respectively. The estimated 5-year overall survival rate was 81.9% with venetoclax and 77.0% with chlorambucil (P = .12). Second primary malignancies were reported in 20.8% of the venetoclax arm and 15.0% of the chlorambucil arm. No new safety signals were reported.

Disclosure: For full disclosures of the study authors, visit library.ehaweb.org.

EHA 2022 Congress

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