GA101 Could Upstage Rituxan in Lymphoma

GA101, an investigational cancer therapy that targets the CD20 receptor found on non-Hodgkin lymphoma cells, could be the next step for patients who relapse on Rituxan (rituximab), a current standard of therapy.

Rituxan also targets the CD20 receptor and uses the body’s immune system to attack cancerous cells. This monoclonal antibody has been around for about a decade and treats several types of non-Hodgkin lymphoma and certain other lymphoid malignancies. “There is a real motivation to take it one step further and create a new [drug] that might work better or to use once Rituxan stops working,” said Laurie H. Sehn, MD, MPH, who headed up the phase 2 study.

Scientists compared GA101, also called obinutuzumab, with Rituxan and found the novel agent improved response rates. Patients with relapsed NHL received either drug for four weekly injections (called induction therapy) and then as maintenance therapy for two years. After two years follow-up, complete remission rates more than doubled from 5.3 percent in the Rituxan arm to 12.2 percent in the GA101 arm. Patients receiving GA101 had a higher risk of infusion reaction, but had fewer severe reactions compared with patients receiving Rituxan. A phase 3 trial is currently under way.

Additional studies are looking at combining GA101 with chemotherapy and testing the drug in both newly diagnosed and relapsed advanced follicular lymphoma as well as newly diagnosed chronic lymphocytic leukemia.