This is a single-arm, open-label, single-dose study consisting of a dose-escalation phase followed by a dose-expansion phase. Four dose levels are planned. Dose escalation will be conducted using an accelerated titration combined with a traditional "3+3" design. A total of 27 to 33 subjects are planned to be enrolled. The primary objective is to evaluate safety, with secondary objectives exploring efficacy and viral shedding. The study duration, from the first subject enrolled to the completion of the last subject's observation period (Day 57 visit), is estimated to be 1 to 2 years. A long-term survival follow-up period of approximately 15 years, or until all subjects are lost to follow-up or deceased, is planned. All data up to Day 57 will be used to support the initiation of a Phase II clinical trial. Any safety and efficacy data will be submitted to regulatory authorities on a rolling basis during the trial.

Inclusion Criteria:

1. Age ≥ 18 years old;
2. Histopathologic or radiological confirmed recurrent supratentorial GBM and measurable lesions (≥1 cm and ≤5.5 cm on contrast-enhanced MRI prior to drug administration).
3. Prior histopathology consistent with the 2021 World Health Organization (WHO) glioblastoma classification.
4. Refractory or relapsed following standard-of-care therapy (surgical resection followed by radiotherapy and concurrent/adjuvant temozolomide);
5. Karnofsky Performance Status (KPS) ≥70 and expected survival time ≥ 3 months;
6. CD155 expression confirmed by immunohistochemistry (H-Score ≥1);
7. Patients should have received a boost immunization with trivalent inactivated between 1 week to 6 months prior to administration of the study agent, with a neutralizing antibody titer ≥1:8 prior to the administration;
8. Able to undergo brain MRI with and without contrast;
9. All subjects and their partners must have no plans for conception from screening until 6 months after the end of the observation period and must agree to use effective non-pharmacological contraceptive measures during the trial;
10. Subjects voluntarily participate in the study, sign informed consent forms, have good compliance, and cooperate with follow-up.

Exclusion Criteria:

1. Patients who are allergic to any component of the investigational drug, contrast agent Maganweixian, or albumin;

2. Patients with an impending, life-threatening cerebral herniation syndrome;

3. Patients with an active infection requiring intravenous treatment or having an unexplained febrile illness (Tmax > 99.5 F/37.5 C);;

4. Patients with known history of immunodeficiency (e.g., positive HIV antibody test), other acquired or congenital immunodeficiency diseases, or organ transplantation;

5. Patients with unstable or severe intercurrent medical conditions such as severe heart (New York Heart Association (NYHA) Class 3 or 4) or uncontrolled diabetes mellitus;

6. Patients with tumor in the brainstem, cerebellum or spinal cord, or leptomeningeal disease;

7. Patients with diffuse subependymal disease;

8. Head MRI suggests tumor enhancement with marginal invasion of the ventricular wall or postoperative tumor cavity connecting to the ventricle;

9. Patients with a previous history of neurological complications due to poliovirus infection;

10. Patients with worsening steroid myopathy (history of gradual progression of bilateral proximal muscle weakness, and atrophy of proximal muscle groups);;

11. Patients with prior, unrelated malignancy requiring current active treatment with the exception of cervical carcinoma in situ and adequately treated basal cell or squamous cell carcinoma of the skin;

12. Patients who have received antitumor therapy (including but not limited to chemotherapy, targeted therapy, immunotherapy, TTFields, or other investigational antitumor drugs) within 4 weeks prior to the first dose of the study drug or within 5 half-lives of the previous drug (whichever is longer), and has not recovered from the toxicities (i.e., to ≤ Grade 1 per CTCAE v5.0, except for alopecia; peripheral neuropathy up to Grade 2 is acceptable);

13. Patients have received bevacizumab ≤ 6 weeks and could not exclude pseudo relievers caused by anti angiogenic inhibitors;

14. Patients who have received Chinese medicine or traditional Chinese patent medicines with anti-tumor effect within 2 weeks prior to the administration of the test drug;

15. Patients who have received radiation therapy within 12 weeks prior to the administration of the investigational drug, excluding those who have undergone radiation therapy for progressive diseases outside the radiation area and cannot rule out pseudoprogression after radiation/chemotherapy;

16. Patients with known history of agammaglobulinemia;

17. Patients on greater than 4 mg per day of dexamethasone or equivalent doses of other hormones (inhaled or localized use of hormones, in the absence of active autoimmune disease) within 2 weeks prior to the administration of the investigational drug;

18. The laboratory tests before biopsy and administration of the test drug meet the following standards:

    • International Normalized Ratio (INR) and Prothrombin Time (PT) ≥1.2 × upper limit of normal (ULN);
    • Serum total bilirubin (TBIL) , AST, ALT >2.5 × ULN;
    • Neutrophil count <1.5×109/L;
    • Hemoglobin <90g/L;
    • Platelet count <100×109/L;
    • Creatinine > 1.5 × ULN;

19. Patients with positive syphilis antibody, or active hepatitis [For hepatitis B: positive hepatitis B surface antigen (HBsAg) or hepatitis B core antibody (HBcAb) and HBV-DNA copy number above the upper limit of normal; for hepatitis C: positive HCV antibody and HCV RNA copy number above the upper limit of normal];

20. Subjects who meet any of the following criteria and have a positive laboratory test result (e.g., T-SPOT.TB test, tuberculosis antibody assay, or tuberculin skin test) that, in the investigator's judgment, indicates an active or suspected tuberculosis (TB) infection.

    • Chest imaging suggests suspicious tuberculosis (TB) infection lesions;
    • Active pulmonary tuberculosis;
    • History of recurrent tuberculosis within 3 years;
    • Contact with or family environment with active tuberculosis patients.

21. Subjects who have received any vaccination within 4 weeks prior to the administration of the study drug, with the exception of the trivalent inactivated poliovirus vaccine, non-live seasonal influenza vaccines, or inactivated COVID-19 vaccines;

22. Pregnancy or lactation, and a woman of childbearing potential who has a positive pregnancy test (within 7 days) prior to treatment;

23. Subjects who are unsuitable for participation in this study at the Investigator's discretion.