ORLANDO, Jan. 22 -- The addition of Avastin (bevacizumab) to Gemzar (gemcitabine) did not improve survival of advanced pancreatic cancer in a randomized trial, researchers reported here.
Median survival of patients randomized in a Cancer and Leukemia Group B phase III trial to Gemzar plus Avastin was 5.7 months, versus 6.0 months for patients taking Gemzar alone, said oncologist Hedy Lee Kindler, M.D., of the University of Chicago Hospitals.
The results of the 602-patient study, she reported at a gastrointestinal cancer symposium here, did not confirm the promising data reported in a phase II trial of the targeted drug, "likely because that small study had proportionally more patients with good prognostic factors."
Gemzar has long been FDA-approved for the first-line treatment of pancreatic cancer. Tarceva (erlotinib), another targeted drug, is approved in combination with Gemzar.
There was also no statistical significance in the progression-free survival, Dr. Kindler added. Median progression-free survival in the Gemzar-Avastin arm was 4.8 months compared with 4.3 months for Gemzar plus placebo.
The Avastin-Gemzar combination was associated with a slight increase in the rate of tumor shrinkage (54%), versus that found in the Gemzar-placebo arm.
The study randomized 302 patients to the Avastin-Gemzar arm and 300 to the Gemzar-placebo arm. It was halted prematurely last June when the data monitoring and safety board determined that the futility threshold had been crossed, said Dr. Kindler. Patients who appeared to benefit Avastin were permitted to continue on it.
The Avastin arm was also associated with greater toxicities, most notably significant increased rates of hypertension and proteinuria.
Dr. Kindler noted that the trial acquired a number of laboratory correlative studies that would be reported in June at the annual meeting of the American Society of Clinical Oncology.
| Dr. Kindler disclosed financial ties with Genentech, Lilly Oncology, and Roche. The National Cancer Institute sponsored the trial, Cancer and Leukemia Group B 80303, under a cooperative agreement between NCI and Genentech.
The Gastrointestinal Cancer Symposium is jointly sponsored by ASCO, the American Society for Therapeutic Radiology and Oncology, the American Gastroenterological Association Institute, and the Society of Surgical Oncology. |