Obinutuzumab is a monoclonal antibody that targets the CD20 antigen on the surface of B-lymphocytes, inducing direct cell death and mediating antibody-dependent cellular cytotoxicity, with less complement-dependent cytotoxicity than rituximab (another CD20-targeting antibody).1,2
The efficacy of obinutuzumab in combination with chlorambucil was compared with that of rituximab plus chlorambucil and chlorambucil monotherapy in 781 patients with previously untreated CLL who also had a co-existing condition (defined as a score of 6 or higher on the Cumulative Illness Rating Scale [CIRS] or a creatinine clearance of 30–69ml/min).2
Obinutuzumab plus chlorambucil was superior to both chlorambucil monotherapy and rituximab plus chlorambucil, with median progression-free survival of 26.7 months compared with 11.1 months and 16.3 months, respectively (p<0.001 for both comparisons).2
Infusion-related reactions and neutropenia were more common with obinutuzumab–chlorambucil than with rituximab–chlorambucil, but the risk of infection was not increased.2
- Gazyvaro Summary of Product Characteristics, July 2014.
- Goede V et al. N Engl J Med 2014; 370: 1101–10.
Further information: Roche