Tumor Treating Fields for Newly Diagnosed Glioblastoma: Two Emulated Trials With Chinese Multi-Hospital Based Real-World Data

Optimizing Tumor Treating Fields Intervention Timing for Newly Diagnosed Glioblastoma: Insights From Two Emulated Trials With Chinese Multi-Hospital Based Real-World Data

The goal of this observational study is to learn about the effectiveness of Optune® (Tumor Treating Fields) in newly diagnosed glioblastoma (GBM) in China. The main question it aims to answer are:

• The efficacy of Optune® as an concomitant/adjuvant to radiation therapy (RT) and temozolomide (TMZ) alone in the treatment of newly diagnosed GBM patients.
• The effectiveness of Optune® given concomitantly with RT and TMZ in newly diagnosed GBM patients, compared to RT and TMZ alone.

Participants will:

• Receive or not receive TTFields.
• Concomitantly or adjuvantly receive TTFields.

The goal of this observational study is to learn about the effectiveness of Optune® (Tumor Treating Fields) in newly diagnosed glioblastoma (GBM) in China. The main question it aims to answer are:

• The efficacy of Optune® as an concomitant/adjuvant to radiation therapy (RT) and temozolomide (TMZ) alone in the treatment of newly diagnosed GBM patients.
• The effectiveness of Optune® given concomitantly with RT and TMZ in newly diagnosed GBM patients, compared to RT and TMZ alone.

Participants will:

Step 1:

• Treatment arm I: Patients receive standard RT + TMZ, followed by maintenance TMZ, with Optune® starts during peri-radiotherapy period (2 month before to 3 months after radiotherapy). The duration of TTFields lasts for at least 2 months.
• Treatment arm II: Patients receive RT and TMZ alone, followed by maintenance TMZ concomitant.

Step 2:

• Treatment arm I: Patients receive TTFields at 200 kHz to the brain using the Optune® System together with RT and TMZ, followed by maintenance TMZ concomitant with the Optune® treatment. The duration of TTFields lasts for at least 2 months. If the subject is assigned to this treatment arm, Optune® therapy will begin no later than the 7th day of RT and TMZ treatment.
• Treatment arm II: Patients receive RT and TMZ alone, followed by maintenance TMZ concomitant with TTFields at 200 kHz to the brain using the Optune® within 3 months after radiotherapy for at least 2 months.

Researchers will compare the overall survival of each arm to see if TTFields demonstrates an improvement in survival outcomes within the Chinese population in real-world practice, and whether this efficacy is further enhanced when combined with RT and TMZ.

Inclusion Criteria:

1. Histologically confirmed diagnosis of GBM according to WHO classification criteria.
2. Age ≥ 18 years.
3. Recovered from maximal debulking surgery.
4. Karnofsky performance status ≥ 60.
5. Planned treatment with RT/TMZ followed by maintenance TMZ.

Exclusion Criteria:

1. Progressive disease (per investigator's assessment).
2. Infratentorial or leptomeningeal disease.
3. Significant co-morbidities at baseline which would preclude maintenance RT or TMZ treatment.
4. Any serious surgical/post-operative condition that may risk the patient according to the investigator.