Evaluating Safety, Tolerability, and Preliminary Efficacy of YSCH-01 Monotherapy and in Combination With Atezolizumab for Recurrent Glioblastoma

Prior treatment

• MRI evidence of tumor enhancement extending to the ventricular wall, or the tumor cavity is fused with the ventricle after surgery.
• Plan or requirement to receive any live vaccine during the screening or treatment phase.

Other illness

• Participants with any of the following conditions are ineligible for enrollment:
• History or current evidence of another primary malignancy.
• Known allergy to the study drug or any of its excipients, or a history of unexplained severe allergic reactions.
• Any contraindication to gadolinium-enhanced MRI, such as presence of a pacemaker, infusion pump, or allergy to MRI contrast agents.
• Tumor involvement of the brainstem, cerebellum, or spinal cord; or leptomeningeal disease.
• Active infection requiring intravenous antibiotic therapy, or unexplained fever (body temperature ≥37.5°C).
• Uncontrolled systemic diseases or relevant medical history, including: diabetes mellitus, cardiovascular/cerebrovascular disease (e.g., heart failure ≥NYHA Class II, hypertension ≥Grade 2, ≥First-degree atrioventricular block, history of myocardial infarction, myocarditis), pulmonary insufficiency, thyroid dysfunction, cerebral infarction within the past 6 months.
• Active autoimmune disease or history of autoimmune disorders (e.g., ulcerative colitis, Crohn's disease, rheumatoid arthritis, systemic lupus erythematosus, autoimmune vasculitis, Wegener's granulomatosis).
• Other conditions assessed as incompatible with intravenous administration of Atezolizumab.

Other

• Preoperative MRI assessment showing the Ommaya puncture path traverses the ventricles.

• Participants must meet all the following criteria to be enrolled in this study:
• Age \> 18 years, male or female.
• Expected survival ≥ 12 weeks.
• Karnofsky Performance Status (KPS) score ≥ 70 at baseline.
• Histopathologically confirmed glioblastoma (GBM), with first recurrence after prior surgery, chemotherapy, and/or radiotherapy.
• Presence of 1 contrast-enhancing tumor lesion (diameter 1-4 cm) assessed by MRI during the screening phase.
• Eligibility for tumor biopsy and Ommaya reservoir implantation based on hematological, hepatic, renal, and coagulation function parameters.
• Recovery from toxic effects of prior chemo/radiotherapy (CTCAE ≤ Grade 1, except for special cases like alopecia or pigmentation), with the Investigator determining that the corresponding adverse events (AEs) pose no safety risk.
• Eligible subjects of reproductive potential (male and female) must agree to use effective contraception during the trial and for at least 6 months after the last dose.