A Phase I/II Study of 7MW4911 to Evaluate the Safety, Pharmacokinetics and Efficacy in Patients With Advanced Colorectal Cancer and Other Advanced Gastrointestinal Tumors

Inclusion Criteria: 1. Aged 18 and above 2. ECOG 0-1 3. Life expectancy ≥ 3 months 4. Advanced or metastatic gastrointestinal cancer that has progressed after standard of care. 5. Disease progression after the most recent treatment regimen 6. At least one measurable lesion according to RECIST v1.1 7. Provision of archival tumor tissue or fresh biopsy. 8. Adequte hematologic funciton, liver function and renal function. 9. Comply with contraceptive requirements Exclusion Criteria: 1. Other concurrent malignancy in the recent 3 years except for adequately treated carcinoma in situ. 2. Active, untreated or symptomatic CNS metastasis 3. Effusions that require frequent drainage 4. Patients with active autoimmune disease, except for type I diabetes, hypothyroidism and other autoimmune disease that does not require systemic treatment. 5. Severe respiratory disease that required hospitalization in the last 28 days. 6. Significant and uncontrolled cardiovascular disease or events in the 6 months prior to study drug administration 7. Poorly controlled blood glucose with fasting blood glucose above 10mmol/L 8. Recipient of allogeneic stem cell transplant or organ transplant 9. Active HIV or hepatitis B/C infection. Infection requiring systemic IV in the 14 days prior to study drug administration. 10. Experiencing toxicities from prior anti-cancer therapies that have not recovered to CTCAE grade 0-1, except for alopecia and endocrinopathies. 11. Prohibited treatment and treatment that requires washout period 1. Has received another Topo-I payload ADC, and/or another CDH17 targeting therapy. 2. Received other cancer therapy within 5 half-lives or 21 days prior to study drug administration. 3. Major surgeries within 28 days prior to study drug administration 4. Investigational therapy within 28 days prior to study drug administration 5. Systemic treatment with immunosuppressive agents within 28 days prior to first drug administration. Physiological dose of glucocorticoid, topical glucocorticoid are allowed. 6. Use of strong CYP3A4 inhibitor or inducer 12. Known hypersensitivity to 7MW4911 or components of the formulation 13. Abuse of narcotic or psychoactive drugs 14. Pregnant or breastfeeding women 15. Other circumstances or conditions where the investigator judges to be unsuitable for study.