- Obinutuzumab is a glycoengineered type II anti-CD20 monoclonal antibody that is able to attack chronic lymphocytic leukemia (CLL) by binding and destroying malignant CLL cells. Rituximab is a non-glycoengineered type I anti-CD20 monoclonal antibody that also binds and kills CLL cells. (Logo: http://mma.prnewswire.com/media/622259/EHA_Logo.jpg ) We conducted a clinical trial in a population of previously untreated patients with CLL and co-existing diseases (CLL11 study). The study included a head-to-head comparison of two chemoimmunotherapies: obinutuzumab (formerly named GA101) plus chlorambucil (G-Clb) versus rituximab and chlorambucil (R-Clb). Previous analyses of the study with median observation times of approx. 20 and 40 months, respectively, demonstrated longer progression-fee survival (PFS; length of time people live without worsening of their disease) for G-Clb when compared with R-Clb. At the 23rd EHA Congress, we present results of the final analysis of the CLL11 study with a median observation time of approx. 5 years. In this analysis, G-Clb was not just confirmed to be superior to R-Clb with regard to PFS but apparently overall survival (OS, length of time people stay alive), too. Furthermore, the median time to the next treatment (i.e. the time of being therapy-free after having finished the study treatment with G-Clb) was approx. 4.5 years and nearly doubled when compared to R-Clb. Study findings: Presenter: Dr Valentin GoedeAffiliation: University Hospital Cologne, GermanyTopic: OVERALL SURVIVAL BENEFIT OF OBINUTUZUMAB OVER RITUXIMAB WHEN COMBINED WITH CHLORAMBUCIL IN PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA AND COMORBIDITIES: FINAL SURVIVAL ANALYSIS OF THE CLL11 STUDY Abstract S151 will be presented by Valentin Goede on Friday, June 15, 16:15-16:30 in Room A1. Embargo Please note that our embargo policy applies to all selected abstracts in the Press Briefings. For more information check our Congress Media Guidelines here. Website: http://www.ehaweb.org