Low-dose Thoracic Radiotherapy Followed by Adebrelimab Plus Chemotherapy, and Then Sequential Maintenance Therapy With Adebrelimab for Extensive-stage Small Cell Lung Cancer

NCT07583550 | Not Yet Recruiting Phase 2

• 1 other identifier: 2026 049 A
• Study Type: interventional
• Target: 43
• Locations: 0 countries
• Sites: N/A

Brief Summary

This study is a multicenter, prospective investigation aiming to evaluate the efficacy and safety of low-dose radiotherapy (15Gy/1.5 Gy bid × 10 fractions) combined with 4-6 cycles of systemic chemotherapy concurrently with Adebrelimab, followed by Adebrelimab maintenance therapy for up to two years, in subjects with extensive-stage small cell lung cancer (ES-SCLC). Additionally, immunohistochemical detection of the expression levels of four key transcriptional proteins-YAP1, NEUROD1, ASCL1, and POU2F3-will be performed to guide the molecular subtyping of SCLC. Based on these findings, we will explore the differential therapeutic outcomes of this regimen across distinct molecular subtypes (A/N/P/Y/I/AN/QN), with the goal of identifying the subject population most likely to benefit from this treatment modality, thereby optimizing clinical decision-making.

Conditions

Radiotherapy; Lung

Outcome Measures

Primary Outcomes (1)

• Progression-Free Survival（PFS）

  Progression-free survival (PFS), defined as the time from the initiation of radiotherapy to the first documented disease recurrence/progression, metastasis, or death from any cause.

  From the date of first radiotherapy to the date of first documented disease progression, metastasis.

Secondary Outcomes (5)

• Overall Survival (OS)

  From date of first radiotherapy to date of death from any cause, assessed up to 36 months.

• Overall Response Rate (ORR)

  Baseline (within 28 days prior to first dose), then every 8 weeks (±7 days) from radiotherapy initiation until 2 years post-treatment.

• Disease Control Rate (DCR)

  Baseline (within 28 days prior to first dose), then every 8 weeks (±7 days) from radiotherapy initiation until 2 years post-treatment.

• Incidence of Treatment-Emergent Adverse Events

  From date of first low-dose radiotherapy to 30 days after last dose.

• To investigate the association between distinct molecular subtypes and clinical outcomes, including prognosis and treatment-related toxicity.

  Baseline: collect tumor tissue (archived FFPE or fresh biopsy) prior to treatment initiation; prognosis follow-up until progression or death (imaging q6w, survival q3m); toxicity monitoring until 30 days post-last dose (recorded at each visit).

Study Arms (1)

Low-Dose Radiotherapy + EP/EC + Adebrelimab

EXPERIMENTAL

All subjects will first receive low-dose radiotherapy (DT 15 Gy, 1.5 Gy per fraction × 10 fractions, BID). Within one week after radiotherapy completion, they will receive 4-6 cycles of systemic chemotherapy (EP or EC regimen) combined concurrently with adebrelimab. Following the 4-6 cycles of chemo-immunotherapy, adebrelimab maintenance therapy will be continued for two years.

Drug: Etoposide; Drug: Cisplatin; Drug: Carboplatin; Drug: Adebrelimab; Radiation: Thoracic Radiotherapy

Interventions

Etoposide DRUG

Etoposide 100 mg/m² on days 1-3 plus cisplatin 25 mg/m² on days 1-3, every 3 weeks (q3w), or etoposide 100 mg/m² on days 1-3 plus carboplatin AUC 5 on day 1, every 3 weeks (q3w).

Low-Dose Radiotherapy + EP/EC + Adebrelimab

Cisplatin DRUG

Etoposide (100 mg/m²) and cisplatin (25 mg/m²) were administered on days 1-3 of each 3-week cycle.

Low-Dose Radiotherapy + EP/EC + Adebrelimab

Carboplatin DRUG

Etoposide (100 mg/m²) was given on days 1-3 and carboplatin (AUC 5) on day 1 of each 3-week cycle.

Low-Dose Radiotherapy + EP/EC + Adebrelimab

Adebrelimab DRUG

20 mg/kg intravenously on day 1, repeated every 21 days (q3w). Administered concurrently with chemotherapy for 4-6 cycles, followed by maintenance monotherapy for up to 2 years.

Low-Dose Radiotherapy + EP/EC + Adebrelimab

Thoracic Radiotherapy RADIATION

All subjects will first receive low-dose radiotherapy (DT 15 Gy, 1.5 Gy per fraction × 10 fractions, BID). Within one week after radiotherapy completion, they will receive 4-6 cycles of systemic chemotherapy (EP or EC regimen) combined concurrently with adebrelimab. Following the 4-6 cycles of chemo-immunotherapy, adebrelimab maintenance therapy will be continued for two years.

Low-Dose Radiotherapy + EP/EC + Adebrelimab

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age ≥18 years and ≤75 years;
• Histologically or cytologically confirmed SCLC;
• No malignant pleural effusion or pericardial effusion;
• No prior history of thoracic radiotherapy or thoracic surgery;
• No prior systemic anti-tumor therapy;
• ECOG performance status 0-2, with a life expectancy of ≥12 weeks;
• At least one measurable lesion per RECIST 1.1 criteria;
• No history of interstitial pneumonia;
• No history of immune-related pneumonitis;
• No history of autoimmune diseases;
• No history of significant active pulmonary infection;
• No use of corticosteroid therapy within 14 days prior to enrollment;
• No Grade ≥3 hematologic toxicity or hepatic/renal impairment;
• No brainstem metastases and no significant neurological symptoms;
• For subjects with coexisting HBV/HCV infection, hepatic impairment ≤ Grade 1 after prior active antiviral therapy;

You may not qualify if:

• Presence of interstitial pneumonia or infectious fever prior to treatment;
• Comorbid autoimmune diseases or long-term oral corticosteroid use (including those who received oral corticosteroids within 14 days prior to treatment);
• Prior history of thoracic radiotherapy or thoracic surgery;
• Presence of Grade ≥3 hematologic toxicity or hepatic/renal impairment;
• Hypersensitivity to adebrelimab;
• Significant respiratory symptoms that preclude tolerance to radiotherapy;
• Active hepatitis B or C infection, currently on antiviral therapy, and with liver function impairment of Grade 2 or above;
• Presence of pleural effusion or pericardial effusion;

Sponsors & Collaborators

• Jiangmen Central Hospital: lead

MeSH Terms

Interventions

Etoposide; Cisplatin; Carboplatin

Intervention Hierarchy (Ancestors)

Podophyllotoxin; Tetrahydronaphthalenes; Naphthalenes; Polycyclic Aromatic Hydrocarbons; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals; Polycyclic Compounds; Glucosides; Glycosides; Carbohydrates; Chlorine Compounds; Inorganic Chemicals; Nitrogen Compounds; Platinum Compounds; Coordination Complexes

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Deputy Director of the Oncology Department

Study Record Dates

• First Submitted: April 21, 2026
• First Posted: May 13, 2026
• Study Start: July 21, 2026
• Primary Completion (Estimated): October 30, 2027
• Study Completion (Estimated): January 1, 2028
• Last Updated: July 22, 2026

Record last verified: 2026-07