Retreatment patterns and outcomes in patients (pts) with gastroenteropancreatic neuroendocrine tumors (GEP-NETs) treated with [ ¹⁷⁷ Lu]Lu-DOTA-TATE ( ¹⁷⁷ Lu-DOTATATE): A PRIME real-world study.

Abstract

625 Background: Available treatment options for advanced GEP-NETs include surgery, somatostatin analogs (SSA), chemotherapy, targeted therapy, liver-directed therapy, or radioligand therapy ( 177 Lu-DOTATATE). This study aims to describe pt characteristics, 177 Lu-DOTATATE treatment patterns (including extension and retreatment), and associated outcomes such as overall survival (OS) and time to next systemic treatment (TTNT) in GEP-NETs. Methods: This retrospective observational study used IQVIA open-source medical and pharmacy claims data from July 1, 2017 to February 28, 2025 for pts with GEP-NETs who received treatment with 177 Lu-DOTATATE. Pt characteristics were collected 6 months prior to index date (first receipt of 177 Lu-DOTATATE). The treatment extension cohort included pts who received ≥4 cycles of 177 Lu-DOTATATE and proceeded directly to additional cycles (C5+) without receiving any other GEP-NET therapy between Cycle 4 and Cycle 5. The retreatment cohort included pts who restarted 177 Lu-DOTATATE after receiving another systemic therapy (using a claim-based proxy). Progression was defined as a switch to another systemic therapy plus initiation of new pain, anti-diarrhea or anti-emetic medication, or hospitalization. All analyses were descriptive. OS and TTNT were evaluated using Kaplan–Meier (KM) analyses. Results: The study population included 3410 pts (median [range] age=67 [18–85] years; 51% male) of which 2306 (68%) had prior systemic treatments, mostly SSAs (62%), chemotherapy (8%), and targeted therapy (6%). Common comorbidities were hypertension (38%), liver/gallbladder/pancreas disease (29%), and diabetes (24%). Among pts with available data (n=2146), most received therapy in an academic setting (87%) compared with a community setting (13%). Pts received a median (range) of 4 (1–8) 177 Lu-DOTATATE cycles. Among pts who switched treatment (n=200; 6%), most switched to chemotherapy (54%) or targeted therapy (35%). In total, 330 (10%) pts received retreatment with 177 Lu-DOTATATE. Of these, 89 (3%) pts extended 177 Lu-DOTATATE therapy (>4 cycles), with a median (range) of 2 (1–4) additional cycles, while 241 (7%) pts received 177 Lu-DOTATATE retreatment, with a median (range) of 3 (1–7) cycles following a progression event. Median OS was 64 (95% confidence interval: 59–68) months from index date. Median TTNT was not reached in KM analyses. Following 177 Lu-DOTATATE extension, 89% of pts were alive or censored at 12 months; 95% of pts were alive or censored at 12 months following 177 Lu-DOTATATE retreatment. Conclusions: Among pts receiving 177 Lu-DOTATATE extension or retreatment, most patients were alive or censored after 12 months.