The goal of this clinical trial is to evaluate the safety, tolerability, pharmacokinetics (PK), and effectiveness of the investigational drug QLS5132 (injectable) in combination with other therapies for participants with advanced solid tumors. This is a multicenter, open-label study consisting of two parts: dose escalation and tumor-specific expansion.

The main questions it aims to answer are:

• In the dose-escalation part: What is the safety, tolerability, PK profile, and preliminary efficacy of QLS5132 combination therapy, and what are the recommended dose(s) for expansion?
• In the expansion part: What is the anti-tumor efficacy and further safety profile of QLS5132 combination therapy at the selected dose(s) in participants with specific tumor types?

Participants will:

• Be enrolled in sequential cohorts to receive QLS5132 in combination with other anticancer agents.
• Undergo regular assessments for safety, drug concentration levels (PK), and tumor response.

Inclusion Criteria:

1. Advanced solid tumors;
2. Measurable disease, per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 (v1.1);
3. Eastern Cooperative Oncology Group (ECOG) performance status 0-1;
4. Adequate organ function;
5. Recover from all reversible AEs from previous anti-tumor treatment (i.e., Grade ≤ 1, according to National Cancer Institute-Common Terminology Criteria for Adverse Events [NCI-CTCAE] v5.0), excluding alopecia (any grade) and Grade ≤ 2 neuropathy peripheral.

Exclusion Criteria:

1. Previous treatment with drugs targeting CLDN6 (including antibody-drug conjugates [ADCs]), or any drug containing topoisomerase I inhibitors (including ADCs);
2. Received prior chemotherapeutic, investigational, or other therapies for the treatment of cancer within 2 weeks with small molecule and within 4 weeks with biologic before the first dose of QLS5132;
3. Progressive or symptomatic brain metastases;
4. Serious, uncontrolled medical disorder, nonmalignant systemic disease, or active, uncontrolled infection;
5. History of significant cardiac disease, or poorly controlled diabetes mellitus;
6. History of recurrent autoimmune diseases;
7. History of myelodysplastic syndrome (MDS) or Acute Myeloid Leukemia (AML);
8. History of a second primary malignancy;
9. If female, is pregnant or breastfeeding;
10. Be allergic to any component of QLS5132 or its excipients.