A phase II trial of cabozantinib in patients with carcinoid and pancreatic neuroendocrine tumors.

228Background: Activation of VEGFR2 and c-MET has been implicated in driving growth of neuroendocrine tumors (NET); additionally, expression of c-MET has been associated with shorter survival. Cabozantinib inhibits VEGFR2 and c-MET. We performed a two-cohort phase II study to evaluate the efficacy of cabozantinib in patients (pts) with advanced carcinoid or pNET (NCT01466036). Methods: Pts with progressive, well differentiated, grade 1-2 carcinoid or pNET were enrolled in parallel cohorts and treated with cabozantinib 60 mg po qd . There was no limit to prior therapy. Pts were restaged every 2 mos for the first 6 mos, then every 3 mos. The primary endpoint was objective response rate as measured by RECIST 1.1. Enrollment of approximately 35 patients of each tumor type was planned. Results: 41 pts with carcinoid (median age 63 yrs, 44% male, % ECOG PS 0/1 = 51/49) were accrued. Accrual to the pNET cohort was halted due to investigator/sponsor decision after 20 pts (median age 55 yrs, 60% male, % ECOG PS 0/...