Inclusion Criteria:

          1. Signed informed consent form and able to comply with the protocol;

          2. Male or female 18 years of age and older;

          3. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 at screening;

          4. Left ventricular ejection fraction (LVEF) ≥ 50% by echocardiography (ECHO);

          5. Patients must have pathologically documented advanced/unresectable or metastatic solid
             tumor with HER2 overexpression/expression that is refractory to standard therapy or
             for which there is no standard available therapy;

          6. Has adequate organ function within 7 days before the first treatment;

          7. Has adequate treatment washout period before the first treatment;:

          8. Patients without a history of AIDS-defining opportunistic infections or with a history
             of AIDS-defining opportunistic infections and have not had an opportunistic infection
             within the past 12 months may be enrolled per the discretion of the Investigator.

        Exclusion Criteria:

          1. Clinically active brain metastases, defined as untreated and symptomatic, or requiring
             therapy with steroids or anticonvulsants to control associated symptoms. Subjects with
             treated brain metastases that are no longer symptomatic and who require no treatment
             with steroids may be included in the study if they have recovered from the acute toxic
             effect of radiotherapy;

          2. Any hematologic malignancies, including leukemia (any form), lymphoma, and multiple
             myeloma;

          3. Cardiovascular dysfunction or clinically significant cardiac disease;

          4. Medical history of clinically significant lung disease or patients who are suspected
             to have these diseases by imaging at screening or requirement for supplemental oxygen;

          5. Known hypersensitivity to either the drug substances or inactive ingredients in the
             drug product;

          6. Grade ≥ 2 peripheral neuropathy;

          7. Unresolved toxicities from previous anticancer therapy;

          8. Cumulative anthracycline dose > 360 mg/m^2 doxorubicin or equivalent;

          9. Uncontrolled infection requiring i.v. of antibiotics, antivirals or antifungals;

         10. Active infection of hepatitis B or hepatitis C;

         11. Patients with a history or current evidence of any concomitant condition, therapy, or
             laboratory abnormality that, in the opinion of the investigator, might confound the
             results of the trial, interfere with the patient's participation and compliance;

         12. Women who are lactating or pregnant, as confirmed by pregnancy test within 7 days
             before first treatment;

         13. Male and female subjects who are unwilling to use adequate contraceptive methods
             during the study and for at least 7 months after the last dose of GQ1001;