The FDA today approved its first “breakthrough” medicine—Genentech’s Gazyva™ (obinutuzumab or GA101), in combination with chlorambucil chemotherapy for people with previously untreated chronic lymphocytic leukemia (CLL).
The Roche subsidiary trumpeted the approval as FDA’s fifth for a new drug developed by the company in the past three years. Gazyva is the first approved drug to have been designated a Breakthrough Therapy by the FDA.
To win the designation, sponsors must offer the FDA preliminary clinical evidence that a drug may offer a “substantial improvement” over available therapies for patients with serious or life-threatening diseases. Gazyva won breakthrough status soon after the biologic license application to support marketing approval was submitted to the FDA.
The agency also granted Gazyva priority review because the drug demonstrated the potential to provide a “significant improvement” in safety or effectiveness in the treatment of a serious condition—as well as an orphan product designation, because it is intended to treat a rare disease.
Genentech persuaded the FDA of the significance of positive progression-free survival results from the Phase III CLL11 trial. In CLL11, which studied a total 356 participants, patients treated with Gazyva in combination with chlorambucil chemotherapy had significantly (84%) reduced risk of disease progression or death compared with the chemotherapy alone. Also, patients who received Gazyva lived significantly longer without their disease getting worse compared to those who received chlorambucil alone—a median of 23 months with Gazyva plus chlorambucil versus 11.1 months on chlorambucil alone.
“Gazyva is an important new medicine for people with newly diagnosed chronic lymphocytic leukemia. It more than doubled the time people lived without their disease worsening compared to chlorambucil alone,” Hal Barron, M.D., CMO and head of global product development, said in a statement. “We have spent 20 years researching blood cancer medicines, and we will continue to study Gazyva to assess its efficacy in other types of blood cancers.”
The most common Grade 3/4 adverse event for those who received Gazyva with chlorambucil was the occurence of infusion-related reactions during the first infusion (21% vs. 0% for chlorambucil alone, since it is an oral medicine). Other adverse effects connected with Gazyva included low platelet count (11% vs. 3% chlorambucil alone) and neutropenia (34% vs. 16% for chlorambucil alone). The increased incidences of neutropenia did not result in an increased rate of infections in the Gazyva arm, researchers concluded. Other adverse reactions included anemia, musculoskeletal pain, and fever.
Final data from CLL11 will be presented at the American Society of Hematology’s 55th Annual Meeting in December 2013. The presentation will include a direct comparison between Gazyva with chlorambucil and Rituxan® (rituximab) with chlorambucil (Stage 2).
Gazyva remains under review by the European Medicines Agency, whose recommendation is usually followed by the the European Commission, the decision-maker for drug marketing across the European Union.