Inclusion Criteria:

   - Histopathologically-confirmed, well-differentiated metastatic neuroendocrine tumor

   - Documented history of carcinoid syndrome and currently experiencing ≥4 bowel movements
   per day during the Run-in period

   - Currently receiving stable-dose somatostatin analog (SSA) therapy

   - Minimum dose of long-acting release (LAR) or depot SSA therapy

      - Octreotide LAR at 30 mg every 4 weeks

      - Lanreotide Depot at 120 mg every 4 weeks

      - Patients who cannot tolerate SSA therapy at a level indicated above will be
      allowed to enter at their highest tolerated dose

   - Ability and willingness to provide written informed consent

Exclusion Criteria:

   - Presence of diarrhea attributed to any condition(s) other than carcinoid syndrome

   - Karnofsky Performance status ≤60%

   - Treatment with any tumor directed therapy, including interferon, chemotherapy,
   mechanistic target of rapamycin (mTOR) inhibitors <4 weeks prior to Screening, or
   hepatic embolization, radiotherapy, radiolabelled SSA, and/or tumor debulking <12
   weeks prior to Screening

   - History of short bowel syndrome (SBS)

   - Clinically significant cardiac arrhythmia, bradycardia, tachycardia that would
   compromise patient safety or the outcome of the study

   - Previous exposure to telotristat etiprate