VG2025 is a Recombinant Human IL12/15 Dual-Regulated Oncolytic HSV-1 Injection. This Phase I study will be conducted in herpes simplex virus (HSV) -seropositive subjects with advanced malignant solid tumors that are refractory to conventional therapies. This is an open label study to determine the safety and tolerability of VG2025, and recommended dose of VG2025 for Phase II trials.

Inclusion Criteria:

1. Age 18 to 75 years (inclusive); Open to all genders.
2. Phase I: Participants with advanced solid tumors who have failed standard therapy (due to intolerance or disease progression following treatment) as confirmed by histopathology and/or cytology, or for whom no standard therapy is currently approved.
3. Participants must test positive for Herpes Simplex Virus Type 1 (HSV-1) antibodies (HSV-1 IgG or HSV-1 IgM).
4. Within 7 days prior to the first administration of the study drug, female participants of childbearing potential must confirm a negative serum pregnancy test. Participants of childbearing potential and their partners must agree to use effective contraception during the study drug administration period and for 90 days after the last dose.

Exclusion Criteria:

1. Participants experiencing an active herpes simplex virus (HSV) recurrence with corresponding clinical manifestations, such as cold sores, herpetic keratitis, herpetic dermatitis, or genital herpes; or those requiring anti-HSV treatment.
2. Participants who have received anticancer therapy or radiation therapy within 4 weeks or 5 half-lives (whichever is shorter) prior to enrollment.
3. Underwent major surgery (excluding needle biopsy or intravenous catheterization) or interventional/ablation therapy within 4 weeks prior to the first dose.
4. Individuals with addiction to alcohol, drugs, or other substances; participants who have been abstinent for more than 2 years are eligible for en.
5. Any other serious underlying medical conditions, or mental or psychological disorders, hereditary diseases, etc., that, in the investigator's judgment, may interfere with disease staging, treatment, or follow-up; affect the participant's compliance; or place the participant at high risk.
6. Any other circumstances that, in the investigator's judgment, render the participant unsuitable for participation in the clinical trial.