Prospective randomized phase II trial of pazopanib versus placebo in patients with progressive carcinoid tumors (CARC) (Alliance A021202).
Bergsland, EK; Mahoney, MR; Asmis, TR; Hall, N; Kumthekar, P; Maitland, ML; Niedzwiecki, D; Nixon, AB; O'Reilly, EM; Schwartz, LH ...
Published in: Journal of Clinical Oncology
4005 Background: Patients (pts) with progressive advanced well-differentiated neuroendocrine tumors arising outside of the pancreas have limited systemic treatment options. Pazopanib (PZ) is an oral multi-kinase inhibitor with activity against VEGFR-2,-3, PDGFR-α, and β, and c-KIT, with initial data suggesting efficacy in CARC. Methods: This was a multicenter, randomized, double-blind, phase II study of PZ (800 mg/day) versus placebo (PL) in progressive CARC. Key eligibility: low-intermediate grade CARC, radiologic progressive disease (PD) < 12 months (mo), and adequate end-organ function. Prior somatostatin analog (SSA) mandated for midgut tumors. Concurrent SSA allowed if previous PD on SSA documented. Primary endpoint was progression-free survival (PFS), defined as time from randomization to PD by central review or death. Secondary endpoints included overall survival (OS), objective response rate (ORR) and safety. The trial had 85% power to detect a difference in median PFS of 14 v 9 mo (hazard ratio [HR] 0.64) at one-sided alpha = 0.1. A stratified log-rank test based on the intend-to-treat (ITT) principle was used. Unblinding and crossover were allowed if PD confirmed by central review. Results: 171 (97 PZ, 74 PL) pts were randomized between 6/2013-10/2015: median age 63; 56% female; 66% small bowel primary; 87% concurrent SSA. Median follow-up of 31 mo; 112 (56 PZ, 56 PL) PFS events observed. 6 pts (4 PZ, 2 PL) remain on initial treatment. Median PFS was 11.6 and 8.5 mo in PZ and PL, respectively (HR = 0.53, 1-sided 90% upper confidence limit [UCL] 0.69, p = 0.0005) which crossed the pre-specified protocol efficacy boundary. 49 PL pts received PZ after PD. Median OS was 41 and 42 mo in PZ and PL, respectively (HR = 1.13, 1-sided 90% UCL 1.51, p = 0.70). RR data will be presented. Notable grade 3+ adverse events were (PZ v. PL %) hypertension (35 v. 8), fatigue (11 v. 4), ALT (10 v. 0), AST (10 v. 0), and diarrhea (7 v. 4). Conclusions: PZ compared to PL was associated with significant improvement in PFS in patients with progressive CARC. The results confirm that VEGF signaling pathway is a valid target for therapy in CARC. Support: U10CA180821, U10CA180882 https://acknowledgments.alliancefound.org . Clinical trial information: NCT01841736.
