Sirolimus for Injection (Albumin Bound) Combined With Octreotide Long-acting Injection in Patients With Metastatic Gastroenteropancreatic Neuroendocrine Tumors

Inclusion Criteria:

* 1\. Unresectable locally advanced or metastatic G1/G2 GEP-NETs diagnosed by histology, according to the 2019 WHO histological grading criteria.
* 2\. Having poor prognostic factors.
* 3\. Non-functional GEP-NETs are required.
* 4\. At least one evaluable lesion meets the RECIST V1.1 standard (Applicable only to the phase II safety run-in stage)
* 6\. ECOG 0\~2.
* 7\. Organ function reserve is good.
* 8\. Be able to sign a written informed consent form.

Exclusion Criteria:

* 1\. Patients who have previously received SSTR-targeted therapies (including somatostatin analogs \[SSAs\] and peptide receptor radionuclide therapy) and/or mTOR inhibitors (Patients who received SSAs in the adjuvant setting and experienced recurrence ≥6 months after treatment completion may be enrolled)\[ Applicable to Phase II dose expansion and Phase III stages\].
* 2\. Has uncontrolled/severe diarrhea or an axillary temperature \> 38.0°C at enrollment.
* 3\. Received treatment with other unlisted clinical investigational drugs within 4 weeks prior to the first use of the investigational drug.
* 4\. Undergone major surgical procedures within 4 weeks prior to the first use of the investigational drug and have not fully recovered.
* 5\. Received systemic use of corticosteroids or other immunosuppressive therapy within 2 weeks prior to the first use of the study drug.
* 6\. With an infection that requires systemic anti-infective treatment within 2 weeks prior to the first use of the study drug.
* 7\. Those who have used strong inhibitors or inducers of CYP3A4 liver metabolic enzymes within 2 weeks prior to the first use of the investigational drug or still need to continue using such drugs.
* 8\. Has a serious history of cardiovascular and cerebrovascular diseases.
* 9\. Having active brain metastasis and/or malignant meningitis.
* 10\. With a history of severe lung diseases.
* 11\. During screening, there may be symptomatic gallstones or a history of symptomatic gallstones but no surgical treatment has been performed.
* 12\. Abnormal thyroid function during screening.
* 13\. Known to have hypersensitivity reactions or intolerance to any component of all investigational drugs or their excipients.
* 14\. Active hepatitis B, active hepatitis C virus infection, or active syphilis infection.
* 15\. History of autoimmune diseases (excluding tuberous sclerosis), history of immunodeficiency, including HIV testing positive, or other acquired or congenital immunodeficiency diseases, or history of organ transplantation.