• Presence of metastasized or locally advanced, unresectable (curative intent), histologically proven, well differentiated Grade 1 or Grade 2 (Ki-67 \<10%) gastroenteropancreatic neuroendocrine tumor (GEP-NET) diagnosed within 6 months prior to screening.

• Participants with high disease burden in the Investigator's opinion. Following criteria should be used as the guiding principle for determining high disease burden:

‣ Primary tumor or a metastatic lesion \> 4 cm

⁃ More than one tumor or metastatic lesions measuring \> 2 cm

⁃ Elevated alkaline phosphatase \> 2.5 X upper limit of normal (ULN)

⁃ Presence of bone metastasis

⁃ Presence of peritoneal metastasis

⁃ Symptoms due to tumor volume such as pain, fatigue, weight loss, anorexia etc.

⁃ Symptoms due to hormone excess requiring active management

⁃ Additionally, participants who, in the Investigator's opinion, have high disease burden due to their disease characteristics not specified above could also be considered eligible.

• Participants ≥ 12 years of age.

• RLI somatostatin receptor (SSTR) uptake on all target lesions (defined by RECIST v1.1 criteria) at least as high as normal liver uptake assessed within 3 months prior to randomization. Any of the RLI modalities as available (some examples are listed below) can be used as per local practice:

‣ \[68Ga\]Ga-DOTA-TOC PET/CT or PET/MRI

⁃ \[68Ga\]Ga-DOTA-TATE PET/CT or PET/MRI

⁃ \[64Cu\]Cu-DOTA-TATE PET/CT or PET/MRI

⁃ Somatostatin receptor scintigraphy (SRS) (planar and/or SPECT/CT) with \[111In\]In-pentetreotide

⁃ SRS (planar and/or SPECT/CT) with \[99mTc\]Tc-octreotide.

• Adequate bone marrow and organ function as defined by the following laboratory values prior to receiving the first study treatment:

‣ White blood cell (WBC) count ≥ 2 x 109/L

⁃ Platelet count ≥ 75 x 109/L

⁃ Hemoglobin (Hb) ≥ 8 g/dL

⁃ Creatinine clearance \> 40 mL/min calculated by the Cockcroft Gault method

⁃ Total bilirubin ≤ 3 x ULN

⁃ Potassium within normal limits. Potassium level of up to 6.0 millimoles per liter (mmol/L) is acceptable at study entry if associated with creatinine clearance within normal limits calculated using Cockcroft-Gault formula. Mild decrease (grade 1) below lower limit of normal (LLN) is acceptable at study entry if considered not clinically significant by Investigator.

• ECOG performance status 0-1.

• Presence of at least 1 measurable site of disease.