This is a multi-center, open-label design to evaluate the safety and tolerance of QLS31905 in patients with advanced solid tumors, together with an assessment of pharmacokinetic characteristics and efficacy.

Inclusion Criteria:

1. Written informed consent.
2. ≥18 years.
3. Female or male.
4. ECOG performance status score 0 or 1.
5. Histologically or cytologically confirmed diagnosis of advanced solid tumors.
6. Adequate haematological, hepatic and renal function.

Exclusion Criteria:

1. Any anticancer therapy or immunotherapy within 4 weeks prior to the start of study treatment.
2. Untreated or symptomatic central nervous system (CNS) metastases or leptomeningeal disease.
3. Patients with a history of monoclonal antibody allergic reaction.
4. Known human immunodeficiency virus infection or known symptomatic hepatitis.