The U.S. Food and Drug Administration has approved the drug Gazyva (obinutuzumab) for use in combination with chlorambucil to treat patients with previously untreated chronic lymphocytic leukemia (CLL).

CLL is a blood and bone marrow disease that typically progresses slowly. According to the National Cancer Institute, 15,680 Americans will be diagnosed with the disease this year and 4,580 will die from it.

Gazyva works by helping specific cells within the immune system attack the cancer cells. Gazyva is intended to be used along with chlorambucil, another drug utilized in the treatment of CLL.

Gazyva is the very first drug with breakthrough therapy designation to receive FDA approval. This designation was requested by the sponsor and granted soon after the biologic license application to support marketing approval was submitted to the FDA. The FDA can only designate a drug as a breakthrough therapy if preliminary clinical evidence indicates the drug could potentially offer a substantial improvement over other available therapies for patients suffering from serious or life threatening diseases.

The FDA also granted Gazyva priority review because the drug demonstrated potential to be a significant improvement in safety or effectiveness in the treatment of a serious condition. They also granted Gazyva orphan product designation because it is intended for the treatment of a rare disease.

“Today’s approval represents an important new addition to the treatments for patients with CLL,” said Richard Pazdur, M.D., 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.”

Gazyva’s approval for CLL is based on a study that included 356 participants in a randomized open-label multi-center trial that compared Gazyva in combination with chlorambucil to chlorambucil alone in participants suffering from previously untreated CLL. Participants receiving Gazyva in combination with chlorambucil showed significant improvement in progression free survival withan average of 23 months compared to 11.1 months with only chlorambucil.

The most common side effects observed in the study participants that received Gazyva in combination with chlorambucil were infusion-related reactions, a decrease in infection-fighting white blood cells, low level of platelets in the blood, low red blood cell count, pain in the muscles and bones, and fever.

Gazyva is being approved with a boxed warning regarding Hepatitis B virus reactivation and a rare disorder that damages the material that covers and protects nerves in the white matter of the brain. These are known risks with other monoclonal antibodies in this class and rare cases were identified in participants on other trials of Gazyva.

Gazyva is marketed by Genentech.