Obinutuzumab

A single low-dose infusion of obinutuzumab at 300 mg/1.73 m² in 41 children with FR/SDNS achieved a median B-cell depletion duration of 8.3 months, consistently longer than prior rituximab. Obinutuzumab has already met its primary endpoint in adult lupus nephritis. Obinutuzumab is a second-generation, glycoengineered, humanised anti-CD20 monoclonal antibody originally developed to overcome rituximab failure in B-cell malignancies. Obinutuzumab binds CD20 at a different epitope than rituximab and is resistant to internalisation. Obinutuzumab's glycoengineering produces more potent ADCC and greater induction of direct cell death compared with rituximab. The OBIRINS trial aims to clarify whether obinutuzumab should replace or supplement rituximab earlier in the treatment pathway rather than being reserved for rituximab-refractory cases.