Overall survival with everolimus, sunitinib, and placebo for advanced pancreatic neuroendocrine tumors: A matching-adjusted indirect comparison of randomized trials.

Abstract

e14621 Background: No randomized trial has compared everolimus (EVE) and sunitinib (SUN) for treatment of advanced pancreatic neuroendocrine tumors (pNET). This study indirectly compared overall survival (OS) with EVE vs. placebo (PBO), and OS and progression-free survival (PFS) with EVE vs. SUN. Methods: Individual patient data were used from the RADIANT-3 trial of EVE 10 mg/day vs. PBO (cutoff: April 2010); published summary data were used from the A6181111 trial of SUN 37.5 mg/day vs. PBO (cutoff: June 2010). To adjust for cross-trial differences, RADIANT-3 patients were subjected to A6181111 exclusion criteria and weighted to match A6181111 baseline demographics, performance status, time since diagnosis, disease sites, distant metastases and prior therapy. After matching, OS was compared between balanced trial populations for EVE vs. the PBO arm from A6181111 (which had access to SUN after progression or early stopping) and vs. the SUN arm. PFS was also compared. Analyses did not adjust for early stopping of A6181111, which may bias towards longer PFS and OS with SUN vs. PBO. Results: 394 patients from RADIANT-3 (after excluding 15 with worse performance status than allowed in A6181111 and 1 missing baseline data) and all 171 patients in A6181111 were included. RADIANT-3 patients differed from A6181111 patients in baseline performance status, prior use of somatostatin analogues, and prior use of systemic chemotherapy before matching. After matching, all baseline characteristics were well-balanced between trials. EVE was associated with significantly prolonged OS vs. PBO in A6181111 (hazard ratio [HR] for death = 0.61, 95% CI = 0.38-0.98, p=0.04), corresponding to a 1-year number needed to treat of 8.3 patients to prevent 1 death. OS and PFS were longer, but not statistically different, with EVE vs. SUN (HR for death = 0.81, 95%CI=0.49-1.31, HR for progression = 0.84, 95% CI=0.46-1.53). Conclusions: After adjusting for cross-trial differences, treatment of advanced pNET with everolimus was associated with significantly prolonged OS compared to placebo. OS and PFS were longer, but not statistically different, with everolimus compared to sunitinib.