Final results of CLL11 confirm superiority of obinutuzumab
Obinutuzumab (GA101; G) is a glycoengineered type II anti-CD20 monoclonal antibody. The randomized phase III CLL11 study compared G plus chlorambucil (Clb) to rituximab (R) plus Clb and to Clb alone in 781 patients with previously untreated CLL and comorbidities, with a median age of 73 years. Previous analyses demonstrated PFS superiority of G-Clb over R-Clb, but for OS statistical significance was not reached.
The final analysis, with a median observation time of approximately 60 months, now demonstrates that treatment with G-Clb results in a clinically meaningful improvement of outcome as compared to R-Clb, as was presented during the Presidential symposium by Dr Valentin Goede (University Hospital Cologne, Germany).
“We did not detect any new late-onset toxicity signals in this final analysis”, Goede said. “Importantly, the rate of fatal adverse events was not higher in the G-arm.” Median PFS was 28.9 months with G-Clb versus 15.7 months with R-Clb (HR 0.49, p<0.0001). This translated in an improvement of time to next treatment (median 56.4 vs 34.9 months, respectively).
Goede: “The final analysis of the CLL11 trial demonstrated a statistically significant prolonged OS in the G-arm compared to the R-arm. Median OS in the R-arm was 73.1 months, whereas in the G-arm it was not reached (HR 0.76, p=0.0245). This difference is clinically meaningful, and also remarkable in the context of the long follow-up given the fact that half of the patients have received at least one salvage treatment in the meantime.”