FDA panel votes 8-2 in favor of Pfizer drug for pancreatic neuroendocrine tumors
NEW YORK—Pfizer Inc. announced that its product Sutent (sunitinib malate) has received recommendation from a United States Food and Drug Administration advisory panel. The U.S. FDA Oncologic Drugs Advisory Committee voted 8-to-2 that Sutent does provide a favorable benefit-risk profile for treating patients with unresectable pancreatic neuroendocrine tumors (NET). The FDA will consider the panel's recommendation when it finalizes its review of Pfizer's supplemental New Drug Application for Sutent for this indication.
"We are encouraged by the panel's favorable review of sunitinib for the treatment of unresectable pancreatic NET. Following today's discussion, we will work closely with the FDA to ensure that it has all of the information that it needs to finalize its review," says Dr. Mace Rothenberg, senior vice president of Clinical Development and Medical Affairs at the Pfizer Oncology Business Unit.
The efficacy of Sutent was studied in a trial, SUN 1111, of 171 patients with progressive, well-differentiated pancreatic NET. Tumor progression in patients taking Sutent stalled for an average time of 11.4 months, while those taking a placebo experienced a median time of 5.5 months. Pfizer noted in March 2009 that the study was stopped early on the advice of an independent monitoring committee, given that it would have been unethical to keep some of the trial patients on the placebo when Sutent had showed a "significant benefit" and that it was likely that the primary endpoint—progression-free survival—for the study would be met if it continued. Given the early conclusion, FDA staff agreed that while Sutent stalled tumor progression for five to six months longer than a placebo, the efficacy might have been overestimated due to early termination. Still, the final analysis showed that Sutent more than doubled the average progression-free survival when compared to placebo in the 171 patients.
If it secures FDA approval in the U.S., Rothenberg says that Sutent "would be a major advancement in the treatment of patients with pancreatic NET, a disease for which there remains a significant unmet medical need."
In Europe, Sutent is indicated for treating unresectable or metastatic, well-differentiated pancreatic NET exhibiting disease progression in adults. It is approved for gastrointestinal stromal tumors after disease progression on or intolerance to imatinib mesylate, as well as for advanced renal cell carcinoma, and is approved for these indications in over 100 countries.
Sutent is a multi-kinase inhibitor that blocks multiple molecular targets implicated in the growth, proliferation and spread of cancer. Two of Sutent's targets, vascular endothelial growth factor receptor and platelet-derived growth factor receptor, are found in many types of solid tumors and are suspected to play a critical role in tumors acquiring the blood vessels, oxygen and nutrients they need for growth. Sutent received FDA approval in 2006 for treating stomach and kidney cancer.
The American Cancer Society's estimates for 2010 were that about 43,140 people will have been diagnosed with pancreatic cancer, and about 36,800 will have died from it. Pancreatic cancer remains "the fourth leading cause of cancer death overall," according to the American Cancer Society's website. Pancreatic NET differ from pancreatic adenocarcinoma, which account for about 95 percent of all pancreatic cancers. Advanced pancreatic NET is reported in two to four people per million annually worldwide, and accounts for about 22 percent to 28 percent of all neuroendocrine tumors. Pancreatic NET is usually considered to be an indolent disease, but for patients with pancreatic NET that has metastasized, the prognosis is poor, consisting of a survival of about one to three years.