First Real-World Evidence on the Safety and Effectiveness of LutatheraTM for Treating Gastroenteropancreatic Neuroendocrine Tumors (GEP-NETs): Insights from Post-Marketing Surveillance

<b>Background/Objectives:</b> This post-marketing surveillance study was conducted to evaluate the safety and effectiveness of [¹⁷⁷Lu]Lu-DOTA-TATE in patients with GEP-NETs in real-world practice in South Korea. <b>Methods:</b> From July 2020 to July 2024, a total of 89 patients from 6 institutions diagnosed with GEP-NETs, as outlined in the approved indication for [¹⁷⁷Lu]Lu-DOTA-TATE, were enrolled. Safety was the primary objective, whereas effectiveness was a secondary objective. In this article, findings were analyzed and compared with the NETTER-1 and NETTER-2 trials. <b>Results:</b> Baseline characteristics were comparable to NETTER-1 and NETTER-2 except for the notably high proportion of G2 (77.1%) among participants. Less than half of patients (41.0%) completed four cycles of [¹⁷⁷Lu]Lu-DOTA-TATE treatment, presenting a lower portion of completion rate compared to 75.7% in NETTER-1 and 87.8% in NETTER-2. Among the 83 patients, 60 patients (72.3%, 239 cases) had at least 1 AE, with 6 patients (7.2%, 8 cases) experiencing SAEs. The most common AE was nausea (34.9%, 46 cases), and most AEs were mild in severity (94.6%, 226 cases). Overall, the safety profile in this study presented minimal differences from NETTER-1 and NETTER-2. This study reports 37.7% of ORR which was between 14.7% in NETTER-1 and 43.0% in NETTER-2. <b>Conclusions:</b> This nationwide post-marketing surveillance study complemented the safety and effectiveness of [¹⁷⁷Lu]Lu-DOTA-TATE among Koreans, which was not probed in two pivotal trials. The data would support the clinical implication of [¹⁷⁷Lu]Lu-DOTA-TATE for the GEP-NETs treatment.