177Lu-edotreotide versus everolimus in patients with advanced neuroendocrine tumors of lung or thymic origin: The phase 3 randomized LEVEL, GETNE-T2217 trial.

Abstract

TPS3177 Background: Everolimus is the only approved drug for the treatment of patients with neuroendocrine tumors (NETs) of lung and thymic origin, showing a median progression-free survival (PFS) of 11 months. Retrospective data for peptide receptor radionuclide therapy (PRRT) have demonstrated promising activity in somatostatin receptor (SSTR)-positive lung NETs. This study aims to compare the efficacy, safety, and patient-reported outcomes of 177Lu-edotreotide versus the standard of care everolimus in patients with advanced lung and thymic NETs. Methods: The LEVEL trial is a randomized, open-label, phase 3 international trial of 177Lu-edotreotide versus everolimus in patients with progressive, advanced, and well/moderately differentiated NETs of lung (typical/atypical) or thymic origin. Patients could be treatment naïve or have progressed (PD) on somatostatin analogues or ≤2 additional systemic treatments. Prior PRRT or mTOR inhibitors are not permitted. Eligible patients are randomly assigned 3:2 to 6 cycles of 177Lu-edotreotide (7.5±0.7 GBq / cycle) or to oral everolimus 10 mg once daily until PD or unacceptable toxicity. Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) scans are performed every 12 weeks until PD. Blood samples are analyzed at baseline, at 1st tumor assessment, and at PD for pharmacodynamic endpoints. Archival tumor tissue samples will be analyzed for ancillary studies. The primary endpoint is PFS according to RECIST v1.1. Secondary endpoints include overall response rate, duration of response, overall survival, safety, and quality of life (assessed through EORTC QLQ-C30). The expected sample size is 120 patients using a two-sided group sequential Lan-DeMets with O’Brien-Fleming-like boundaries test to demonstrate statistically significant risk reduction of 46.4% (HR= 0.536) in PFS between arms (α=0.05, β=0.2). The study has received institutional review board/ethics committee approval. Recruitment started in Oct 2023. Thirteen patients are already included. Clinical trial information: NCT05918302 .