This study is a multicenter, open-label, multi-dose, first-in-human (FIH) Phase I/IIa study to determine the safety and tolerability of VBC103, as well as the maximum tolerated dose (MTD) and/or recommended Phase II dose (RP2D), PK and further evaluate its efficacy.

Protocol Version：V1.1 Version Date：2025-12-12

Inclusion Criteria:

• 1.The subject or their legal representative is willing and able to sign a written ICF before initiating any study procedures.
• 2.Histologically or cytologically confirmed unresectable advanced/metastatic solid tumor that has recurred or progressed during or after standard systemic therapy, or is intolerant to standard therapy, or lacks standard treatment options (applicable only to Phase I and Phase IIa Cohort 5).
• 3.At least one measurable lesion as assessed by the investigator per RECIST v1.1.
• 4.Adult male or female (defined as ≥18 years of age)
• 5.ECOG performance status score of 0-1.
• 6.LVEF ≥50% as measured by ECHO or MUGA within 28 days prior to enrollment.
• 7.Life expectancy exceeding 12 weeks.
• 8.Availability of archived tumor tissue samples or willingness to undergo biopsy sampling.

Exclusion Criteria:

• 1.Any unresolved ≥Grade 2 toxicity from prior anticancer therapy.
• 2.Known active keratitis or corneal ulcer.
• 3.History of interstitial lung disease (e.g., non-infectious interstitial pneumonia, pneumonitis,pulmonary fibrosis, or severe radiation pneumonitis), current interstitial lung disease, or suspected interstitial lung disease based on imaging during the screening period.
• 4.History of underlying pulmonary diseases, including but not limited to pulmonary embolism within 3 months prior to the start of investigational product, severe asthma, severe chronic obstructive pulmonary disease, restrictive lung disease, and other clinically significant pulmonary impairment or requiring supplemental oxygen, as well as any autoimmune, connective tissue, or inflammatory disease involving the lungs (such as rheumatoid arthritis, Sjögren's syndrome, sarcoidosis, etc.) and/or prior pneumonectomy (complete resection).