The U.S. Food and Drug Administration (FDA) has approved obinutuzumab (Gazyva) for use in combination with chlorambucil (Leukeran) to treat patients with previously untreated chronic lymphocytic leukemia (CLL).
Obinutuzumab is the first drug with Breakthrough Therapy designation to receive FDA approval. This designation was requested by the sponsor, Genentech, and granted soon after the Biologic License Application to support marketing approval was submitted to the FDA.
The FDA also granted obinutuzumab priority review because the drug demonstrated the potential to be a significant improvement in safety or effectiveness in the treatment of a serious condition. And the FDA granted obinutuzumab orphan product designation because it is intended to treat a rare disease.
“Today’s approval represents an important new addition to the treatments for patients with CLL,” said Richard Pazdur, MD, Director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “This approval reflects the promise of the Breakthrough Therapy designation program, allowing us to work collaboratively with companies to expedite the development, review, and availability of important new drugs.”
Obinutuzumab’s approval for CLL is based on a study of 356 participants in a randomized open-label multicenter trial comparing obinutuzumab in combination with chlorambucil to chlorambucil alone in participants with previously untreated CLL. Participants receiving obinutuzumab in combination with chlorambucil demonstrated a significant improvement in progression-free survival: an average of 23 months compared with 11.1 months with chlorambucil alone.
The most common side effects observed in participants receiving obinutuzumab in combination with chlorambucil were infusion-related reactions, neutropenia, thrombocytopenia, anemia, musculoskeletal pain, and pyrexia.
Obinutuzumab is being approved with a boxed warning regarding hepatitis B virus reactivation and progressive multifocal leukoencephalopathy. These are known risks with other monoclonal antibodies in this class, and rare cases were identified in participants on other trials of obinutuzumab. Patients should be advised of these risks and assessed for hepatitis B virus and reactivation risk. ■