An open-label, multicenter phase Ib/II clinical study to evaluate the safety and efficacy of LBL-024 combined with etoposide and platinum in the first-line treatment of patients with advanced neuroendocrine carcinoma (NEC)

This trial includes two parts: phase Ib and phase II study. Phase Ib is a dose-escalation and Phase II is the dose optimization and dose expansion .

Phase Ib program to enroll patients with advanced neuroendocrine carcinoma (NEC) without systemic therapy.To sequentially evaluate the safety and tolerability of LBL-024 in combination with etoposide and platinum (cisplatin or carboplatin) at different doses by the dose-escalation method.

Phase II includes two stages, dose optimization and dose expansion.

The dose optimization part will conduct combination of LBL-024, which is a further optimization study in two dose groups, enrolling patients with EP-NEC who have not received systemic treatment, to fully assess the dose-exposure-effect relationship, and in combination with the target binding characteristics of LBL-024, pharmacokinetic/pharmacodynamic, efficacy and/or safety profile, considering multiple dimensions,To confirm the rationale for the recommended Phase 2 dose (RP2D).

The dose expansion:the recommended Phase 2 dose (RP2D) will be determined based on the safety, tolerability, efficacy and PK data from the clinical studies of LBL-024.After obtaining the RP2D, a dose expansion study of combination dosing at the RP2D will be conducted to obtain adequate efficacy data.

This trial will enroll 178 patients in Phase Ib and Phase II study.

Inclusion Criteria:

1. Agree to follow the trial treatment regimen and visit schedule, voluntarily enroll, and sign the written informed consent.
2. aged 18-75 years (including borderline values) at the time of signing the informed consent form
3. The Eastern Cooperative Oncology Group's physical status scoring standard (ECOG) is 0~1.
4. The expected survival time is at least 12 weeks.
5. According to the evaluation of RECIST 1.1 （Response Evaluation Criteria in Solid Tumours），the subjects enrolled have at least one measurable target lesion.
6. Fertile men and women of childbearing age are willing to take effective contraceptive measures from the signing of the informed consent form to 6 months after the last dose of the investigational drug; women of childbearing age include premenopausal women and women who had menopause less than two years ago. Blood pregnancy test results must be negative for women of childbearing age within 7 days prior to the initial dose of the investigational drug.

Exclusion Criteria:

1. Subjects who underwent major organ surgery (excluding needle biopsy) or significant trauma within 4 weeks prior to the initial use of the investigational drug, or require elective surgery during the trial period
2. Use of immunomodulatory drugs within 14 days prior to the initial use of the investigational drug, including but not limited to thymosin, interleukin, and interferon
3. Subjects with an active infection that currently requires intravenous anti-infective therapy.
4. Clinically uncontrollable pleural effusion, pericardial effusion, and requiring repeated drainage or medical intervention.
5. medical history of immunodeficiency including HIV antibody positive.
6. Pregnant or lactating women.
7. The investigator believes that the subject has other conditions that may affect compliance or that are not suitable for participating in this study.