Inclusion Criteria:
1. age ≥18 years old, male and female, voluntarily sign informed consent;
2. Estimated survival ≥3 months as assessed by the investigators;
3. the Eastern UnitedStates Cancer Consortium (ECOG) physicalstatu sscore requirements of 0 to 1 points;
4. Included in the crowd:
1. Dose escalation stage: Patients with HER-2 expression confirmed by histopathology and cytopathology (including IHC3+, IHC2+/FISH+ and IHC2+/FISH-) who have failed standard therapy or have no standard treatment options or are not suitable for standard therapy at this stage, The climbing stage includes but is not limited to breast cancer, stomach cancer, non-small cell lung cancer, biliary tract cancer, colorectal cancer, urothelial carcinoma, etc.
2. Dose expansion phase: divided into 3 cohorts i. Cohort A: Patients with breast cancer with HER-2 expression (including IHC3+, IHC2+/FISH+ and IHC2+/FISH-) confirmed by histopathology and cytopathology after failure of standard treatment or no standard treatment regimen or unsuitable for standard treatment at this stage; ii. Cohort B: Patients with histopathologically confirmed and inoperable locally advanced or metastatic urothelial carcinoma, including urinary bladder, pelvis, ureter, and urethral origin with HER-2 expression (including IHC3+, IHC2+/FISH+, and IHC2+/FISH-); iii. Cohort C: patients with gastric adenocarcinoma (including gastroesophageal junction adenocarcinoma) with disease progression after standard therapy, or histologically or cytologically proven metastatic or unresectable locally advanced or metastatic HER-2 expression (including IHC3+, IHC2+/FISH+, and IHC2+/FISH-) who are intolerant to standard therapy;
5. the dose escalation phase must have an evaluable tumor lesion, and the dose expansion phase must have at least one measurable tumor lesion (according to RECIST 1.1 criteria);
6. Pregnant women must have a negative pregnancy test during the screening period, before first dosing, and on the first day of each cycle. Consent must be given to the use of effective contraceptive methods to prevent pregnancy. No egg donation. And willing to take effective contraceptive methods to prevent pregnancy after signing the informed consent until 90 days after the last dosing of the study.
Exclusion Criteria:
1. During previous treatment with HER2-targeted drugs such as trastuzumab or pertuzumab, T-DM1, vedicitumab or Enhertu, as well as topoisomerase I inhibitors (such as irinotecan), grade 3 aes (including but not limited to infusion reactions or allergic reactions) that were determined to be treaty-related or of unknown drug relationship, or L after treatment VEF \< 50%;
2. Participants who had previously received doxorubicin with cumulative dose \> 360 mg/m2 or equivalent anthracyclines;
3. Before the first administration of the investigational drug, AE (CTCAE5.0) caused by previous antitumor therapy still had grade 1, except for the following cases: a. Hair loss; b Pigmentation; c. Patients with distal toxicity caused by chemotherapy and radiotherapy who can not be further recovered by judgment;
4. primary central nervous system tumor or symptomatic central nervous system metastasis, meningeal metastasis or a history of epilepsy. Patients with asymptomatic or asymptomatic central nervous system metastases under clinical control or who have symptoms but are judged to be stable by the investigators can be included, provided that the following conditions are met :a. The clinical symptoms were stable ≥4 weeks before the first dose. b. Brain MRI enhancement showed no evidence of progression of central nervous system disease within 4 weeks prior to initial administration; c. Antiepileptic drugs, hormones and other drugs have been stopped ≥2 weeks before the first administration;
5. Major surgical procedures were performed within 28 days prior to the first use of the study drug, or if postoperative complications persist after 21 days;
6. Subjects who have had a severe infection within 4 weeks prior to first dosing, or who have any signs and symptoms of active infection within 2 weeks prior to first dosing;
7. Subjects who have not been treated or are being treated for tuberculosis, including but not limited to tuberculosis (those who have been treated with standardized anti-tuberculosis therapy and have been confirmed cured by the investigator), a history of immunodeficiency, including human immunodeficiency virus (HIV) infection, or other immunodeficiency diseases, or a history of organ transplantation;
8. there are infected with the following diseases: active hepatitis B virus infection \[hepatitis B surface antigen (HBsAg) positive, and hepatitis B virus deoxyribonucleic acid (HBV-DNA) test \>200 IU/ml or 103 copies /ml (or \> the normal high value of the study center detection)\]; Hepatitis C virus infection \[HCV antibody and viral ribonucleic acid (HCV-RNA) test positive\]; Treponema pallidum antibody positive and RPR positive;
9. Patients with symptomatic congestive heart failure (NYHA grade II to IV) or severe arrhythmias requiring treatment (12-lead ECG QTc extension of 450 ms \[male\], 470 ms \[female\]), myocardial infarction, unstable angina in the last 6 months. Except atrial fibrillation or paroxysmal supraventricular tachycardia;
10. Patients with a history of non-infectious pneumonia requiring glucocorticoid therapy or with current interstitial lung disease;
11. the presence of any other serious underlying medical conditions (e.g. Gilbert's syndrome, uncontrolled diabetes, uncontrolled hypertension, active gastric ulcers, uncontrolled seizures, cerebrovascular events, gastrointestinal bleeding, severe signs and symptoms of coagulation and coagulation disorders), psychiatric/psychological/family factors that the investigator determines may influence screening, treatment, and follow-up. Affect compliance or put patients at high risk for treatment-related complications;
12. The previous anti-tumor therapy (such as chemotherapy, endocrine therapy, targeted therapy, immunotherapy or tumor embolization, etc.) is less than 28 days from the first study (or if the half-life of the drug is 5 times shorter than 28 days, the sponsor and the researcher shall decide whether to include it according to the specific analysis of the specific circumstances). Note that castration for prostate cancer and bisphosphonate or dinomumab for osteoporosis are permitted. Patients whose previous palliative radiotherapy was less than 7 days removed from the first study, or whose previous wide-field radiotherapy was less than 28 days removed from the first study, or who had not recovered from the side effects of radiotherapy as determined by the investigators;
13. Therapeutic radiopharma use must be discontinued 8 weeks before the first study administration;
14. Known allergy or intolerance to the investigational drug or its excipients;
15. Pregnant or lactating women;
16. Subjects considered unsuitable for participation in this study by the researcher.
