Almost one-third of patients with diffuse large B-cell lymphoma (DLBCL) or follicular lymphoma who had failed prior treatment saw their tumors completely eliminated by the combination of Hu5F9-G4 and Rituximab. A study based on the results of these trials was published in the New England Journal of Medicine.
“While newer therapies have shown robust activity in r/r NHL [relapsed or refractory non-Hodgkin’s lymphoma], there remains an unmet need for new medicines that are both well-tolerated and able to induce clinically meaningful responses in patients who need urgent treatment”, said in a press release Sonali Smith, MD, senior author of the study.
Cancer cells often produce a certain protein (CD47) in order to fool the immune system and avoid detection. The Hu5F9-G4 (5F9 for short) antibody is a macrophage immune checkpoint inhibitor blocking CD47, inducing tumor-cells to get engulfed and destroyed by antibodies.
Clinical trials included 22 patients, with an average age of 59 years, that had received previous lines of therapy but were unsuccessful. Overall, 50% of patients responded to the combination, including 36% complete responses. Six and eight-month follow-ups showed that 91% of patients had an ongoing response.
Most side effects were mild and included chills, headache, anemia, and infusion-related reactions. In the majority, they occurred within the first few weeks without long-term toxic effects.
“The publication of these Phase 1b data in the NEJM underscores the potential of CD47 inhibition as a novel approach to treating cancer, and reinforces the strong therapeutic potential of 5F9 as a safe and efficacious option for patients with r/r NHL [relapsed or refractory non-Hodgkin’s lymphoma]”, added Smith, Professor in Medicine and director of the Lymphoma Program at the University of Chicago Medicine.