Sutent Approved for Pancreatic Neuroendocrine Tumors

The oral tyrosine kinase inhibitor sunitinib (Sutent) was approved May 20 for treatment of patients with metastatic pancreatic neuroendocrine tumors, according to the Food and Drug Administration.

Approval of sunitinib (Sutent, Pfizer) for the indication follows closely the May 5 approval of everolimus (Afinitor) for the treatment of advanced pancreatic neuroendocrine tumors. The two approvals mark the first new treatments in roughly 30 years for advanced pancreatic neuroendocrine tumors. There are an estimated 1,000 new cases of the tumor in the United States each year.

According to the FDA, the most commonly reported side effects of sunitinib include diarrhea, nausea, vomiting, fatigue, anorexia, high blood pressure, energy loss (asthenia), abdominal pain, changes in hair color, inflammation of the mouth (stomatitis), and a decrease in infection-fighting white blood cells (neutropenia).

Sutent is also FDA approved to treat patients with late-stage kidney cancer (metastatic renal cell carcinoma) and to treat patients with gastrointestinal stromal tumor or GIST.

In April, the FDA’s Oncologic Drug Advisory Committee voted 8-2 that the sunitinib’s risk-benefit profile was favorable for patients with this rare cancer. Their recommendation was based on the published results of a planned trial of 171 patients randomized to either 37.5 mg/day of oral sunitinib or placebo. Sunitinib doubled median progression-free survival for patients with advanced pancreatic neuroendocrine tumors from 5.5 months to 11.4 months. The probability of progression-free survival at 6 months was 71% in the sunitinib group and 43% in the placebo group (N. Engl. J. Med. 2011;364:501-13).

The trial was halted after randomization of 154 patients, when a data and safety monitoring committee found a greater number of serious adverse events and deaths in the placebo group. There were 9 deaths in the sunitinib group (10%) vs. 21 deaths in the placebo group (25%). The hazard ratio for death was 0.41 (P = .02) in favor of sunitinib. Eight patients on sunitinib had confirmed tumor responses (two complete responses and six partial responses) for an objective response rate of 9.3%.

At the committee meeting, members of the ODAC and the FDA expressed concerns that early termination of the study could have overestimated the magnitude of the treatment difference on progression-free survival, the primary end point of the study.