Brachytherapy With Radiotherapy and Immunotherapy: Guided HDR Trial in Esophageal Squamous Cell Carcinoma

Official title

A Phase II Study of High-Dose-Rate Esophageal Brachytherapy After External Beam Radiotherapy and Nivolumab in Patients With Locally Advanced Esophageal Squamous Cell Carcinoma

Overview

The goal of this clinical trial is to learn if adding high-dose-rate (HDR) brachytherapy can improve outcomes in patients with locally advanced esophageal squamous cell carcinoma (ESCC) who have already received external beam radiotherapy (EBRT), chemotherapy, and the immune therapy drug nivolumab. The main questions it aims to answer are: * Does HDR brachytherapy reduce the chance of the cancer coming back in the esophagus or nearby areas within 12 months? * What side effects or safety issues occur when HDR brachytherapy is given after EBRT, chemotherapy, and nivolumab? Participants will: * Receive 1-2 sessions of HDR brachytherapy delivered through a thin tube placed inside the esophagus, within three weeks after starting nivolumab. * Continue nivolumab and be monitored with regular follow-up visits, imaging tests, and blood samples to check treatment response and safety.

Detailed description

This is a single-arm, phase II clinical trial designed to evaluate the efficacy and safety of high-dose-rate (HDR) esophageal brachytherapy in combination with external beam radiotherapy (EBRT), chemotherapy, and immune checkpoint inhibition with nivolumab in patients with locally advanced esophageal squamous cell carcinoma (ESCC).

Eligible patients include those with stage III-IVB ESCC who have previously received EBRT with concurrent platinum-fluoropyrimidine chemotherapy and who have initiated nivolumab therapy. HDR brachytherapy (5-12 Gy in 1-2 fractions) will be administered within three weeks following the start of nivolumab.

The primary endpoint is the 12-month cumulative incidence of locoregional failure. Secondary endpoints include overall survival, progression-free survival, overall response rate, disease control rate, safety and tolerability, tube-dependence-free survival, tumor-infiltrating lymphocyte density, and circulating tumor DNA dynamics.

The rationale for this trial is that HDR brachytherapy offers precise dose escalation directly to the esophageal tumor, which may improve locoregional control beyond EBRT alone. In addition, the combination of localized high-dose irradiation with systemic immune checkpoint inhibition has the potential to enhance antitumor immunity, thereby improving clinical outcomes in this high-risk population.

Interventions

• Drug Nivolumab (240 mg)
  After the first cycle of nivolumab administered in the screening phase (1st cycle), nivolumab in the study phase was administered intravenously over 30 minutes at a dose of 240 mg every 2 weeks for at least 2 doses, with 1 cycle after to first brachytherapy (2nd cycle), and 1 more cycle after to second brachytherapy (3rd cycle) if feasible. (each cycle was 2 weeks), until disease progression assessed by the investigator per RECIST version 1.1, or unacceptable toxicity.
• Radiation Brachytherapy
  Brachytherapy protocol starts within 3 weeks after first cycle of nivolumab was administered. After brachytherapy applicator placement, CT simulation scan(s) with dummy source in place will be done for further planning procedure, including adjustment of the applicator and 3D treatment planning. High-dose-rate (HDR) 5-Gy per fraction is delivered to the gross tumor volume (GTV) of esophageal tumor(s), second treatment if applicable will be finished within 2 weeks after the first fraction, a total

Primary outcome measures

• Cumulative incidence of locoregional failure at 12 months [Time frame: 12 months from initiation of HDR brachytherapy]

Secondary outcome measures (10)

• Overall Response Rate (ORR) [Time frame: Up to 24 months]
• Overall Survival (OS) [Time frame: Up to 24 months]
• Progression-Free Survival (PFS) [Time frame: Up to 24 months]
• Disease Control Rate (DCR) [Time frame: Up to 24 months]
• Duration of Response (DoR) [Time frame: Up to 24 months]
• Cumulative incidence of distant failure [Time frame: Up to 24 months]
• Safety and tolerability [Time frame: From first study treatment through 90 days after last dose and up to 24 months for late effect]
• Tube-dependence-free survival [Time frame: Up to 24 months]
• Circulating tumor DNA (ctDNA) dynamics [Time frame: Baseline and up to 24 months]
• Tumor-infiltrating lymphocyte (TIL) density [Time frame: Baseline to up to 12 weeks after HDR brachytherapy]

Eligibility criteria

Inclusion criteria

• Age of 18-85 years, with ECOG performance 0-2.
• Locally-advanced esophageal squamous cell carcinoma with clinical stage III, IVA with biopsy proven.
• Prior treatment with EBRT (40-50.4 Gy in 20-28 fractions) and platinum + fluoropyrimidine chemotherapy, with residual or progressive disease, and deemed inoperable or unable to undergo surgery.
• No prior exposure to ICIs and had received first cycle of nivolumab after CCRT.
• Biopsy proven with PD-L1 \[tumor cell (TC) ≥ 1%\]
• Required at least one measurable or non-measurable lesion per Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1.
• Patients with limited stage IVB disease (e.g., non-visceral lymph node metastasis) may be enrolled if the primary tumor is locally dominant and suitable for brachytherapy, based on investigator's discretion.

Exclusion criteria

• Current or past history of severe hypersensitivity to any other antibody products.
• Patients with any metastasis in the brain or meninx that is symptomatic or requires treatment.
• Patients with active, known or suspected autoimmune disease
• Stenosis of esophageal lumen that cannot performed brachytherapy
• Involvement of tracheal mucosa or bronchial mucosa.
• The distribution of the lesions of interest exceeds 10 cm range.
• The patient is participating in other interventional clinical trials associated with immunotherapy.
• The patient is scheduled to undergo esophagostomy.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

N/A

Model

Single group

Masking

Open label

Primary purpose

Treatment

Study locations

Taiwan · 1 center

• National Taiwan University Hospital Yunlin Branch — Huwei

Identifiers

NCT: NCT07152678 · 202505130MIND

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗