Genentech and Biogen Idec have submitted two supplemental Biologics License Applications (sBLAs) to the FDA for Rituxan plus standard chemotherapy for people with previously untreated or treated chronic lymphocytic leukemia (CLL). The companies will request a priority review, and if granted, anticipate the FDA will make a decision within six months.

CLL is the most common type of adult leukemia, accounting for one-third of all leukemias in the U.S. It is a slow-growing disease that occurs when too many abnormal white blood cells develop in the blood and bone marrow. The abnormal cells outnumber the normal white blood cells, making it difficult for the body to fight infection.

The applications are based on positive results from two of the largest global Phase III clinical trials conducted in patients with CLL. The randomized, comparative studies, known as CLL8 and REACH, showed that Rituxan plus standard chemotherapy for CLL extended the time patients lived without the cancer advancing (progression-free survival or PFS) compared to those receiving chemotherapy alone. In CLL8, previously untreated patients who received Rituxan plus chemotherapy had a 69% improvement in PFS (41% risk reduction, hazard ratio=0.59; p<0.0001; 95% confidence interval: 0.44,0.72) compared to those who received chemotherapy alone. In REACH, patients whose cancer relapsed after previous treatment had a 54% improvement in PFS after receiving Rituxan plus chemotherapy compared to patients receiving chemotherapy alone (35% risk reduction, hazard ratio=0.65; p=0.0002; 95% confidence interval: 0.51, 0.82). These findings were based on assessments made by the study investigators.

“There is no cure for CLL, and the primary goal of treatment is to keep the cancer from getting worse,” said Cecil Pickett, Ph.D., Biogen Idec’s president of R&D. “These data showed that Rituxan was able to extend the period of time before cancer progression by about 10 months for people with newly diagnosed or recurrent disease.”

“Results from these two large studies, which involved nearly 1,500 patients, give us confidence in Rituxan’s efficacy and safety in CLL,” said Hal Barron, M.D., executive vice president, Global Development and chief medical officer, Genentech. “We believe the data support the potential role of Rituxan as both an initial and second-line treatment for CLL, and look forward to working with the FDA during the review period.”