A Phase I Clinical Study to Evaluate the Safety, Tolerability, and Pharmacokinetics of HLX3901 in Patients With Advanced SCLC or NEC

Inclusion criteria

• ✓. Have a full understanding of the study content, process, and possible adverse reactions before the study, and sign the informed consent form (ICF); voluntarily participate in the study; be able to complete the study as per protocol requirements;
• ✓. Aged ≥ 18 years and ≤ 75 years at the time of signing the ICF, male or female;
• ✓. Histologically or cytologically confirmed advanced small cell lung cancer or neuroendocrine carcinoma; patients with advanced small cell lung cancer must have experienced intolerance, recurrence, or disease progression following prior treatment with a platinum-based therapy combined with immune checkpoint inhibitors, while patients with neuroendocrine carcinoma must have experienced intolerance, recurrence, or disease progression following prior platinum-based therapy; allowed histological subtypes include combined small cell lung cancer and mixed neuroendocrine-non-neuroendocrine neoplasms.
• ✓. At least one measurable lesion as per RECIST 1.1 within 4 weeks prior to the first administration;
• ✓. An ECOG performance status score of 0-1 within 7 days prior to the first administration;
• ✓. Expected survival \> 3 months;
• ✓. The following conditions must be met in terms of the time of the first administration of the investigational product: at least 28 days from the previous major surgery, medical device treatment, locoregional radiotherapy (except for palliative radiotherapy for bone lesions), cytotoxic chemotherapy, immunotherapy, or biological product therapy; at least 14 days from the previous small molecule targeted drug therapy and previous hormone therapy; at least 7 days from the previous administration of the traditional Chinese medicine for anti-tumor indications or minor surgery; recovery of treatment-induced AEs to Grade ≤ 1 (CTCAE v6.0, except for alopecia);
• ✓. Participants who agree to provide archived tumor tissue specimens that meet the testing requirements (either from the most recent surgery or biopsy, preferably within 2 years) or agree to undergo a biopsy to collect tumor tissue for DLL3 expression testing; Note: Formalin-fixed paraffin-embedded (FFPE) tumor samples (paraffin blocks or unstained sections, which must meet the quality control criteria for testing) collected from non-radiotherapy sites during the most recent surgery or biopsy at or after the diagnosis of malignant tumor and pathological reports of such specimens shall also be provided.