A Study Comparing QLC5508 in Combination With QL2107 Versus Tislelizumab Plus Platinum-based Chemotherapy in Participants Wih Treatment-naïve Extensive-Stage Small Cell Lung Cancer

NCT07802821 | Not Yet Recruiting Phase 3 DMC

• 1 other identifier: QLC5508-304
• Study Type: interventional
• Target: 556
• Locations: 0 countries
• Sites: N/A

Brief Summary

This trial is a Phase III, randomized, open-label, multicenter study to evaluate the efficacy and safety of QLC5508 in combination with QL2107 versus Tislelizumab plus platinum and etoposide as first-line treatment in participants with extensive-stage small cell lung cancer.

Conditions

Extensive-stage Small Cell Lung Cancer

Outcome Measures

Primary Outcomes (1)

• Overall survival (OS)

  OS is defined as the duration from the date of randomization to the date of death due to any cause.

  Up to approximately 36 months

Secondary Outcomes (9)

• Progression-free survival (PFS)

  Up to approximately 36 months

• Objective response rate (ORR)

  Up to approximately 36 months

• Duration of response (DOR)

  Up to approximately 36 months

• Disease control rate (DCR)

  Up to approximately 36 months

• 6-month PFS rate

  Up to approximately 36 months

Study Arms (2)

QLC5508 in combination with QL2107

EXPERIMENTAL

Drug: QLC5508; Drug: QL2107

Tislelizumab in Combination with Platinum-based Chemotherapy

ACTIVE COMPARATOR

Drug: Tislelizumab; Drug: Carboplatin; Drug: Cisplatin; Drug: Etoposide

Interventions

QL2107 DRUG

QL2107 will be administered intravenously once every 3 weeks. Treatment will continue until disease progression or unacceptable toxicity. The maximum treatment duration for QL2107 will be 2 years.

QLC5508 in combination with QL2107

Tislelizumab DRUG

Tislelizumab will be administered intravenously once every 3 weeks. Treatment will continue until disease progression or unacceptable toxicity. The maximum treatment duration for Tislelizumab will be 2 years.

Tislelizumab in Combination with Platinum-based Chemotherapy

Carboplatin DRUG

Carboplatin will be administered intravenously once every 3 weeks. Carboplatin treatment will be administered for up to 4 cycles.

Tislelizumab in Combination with Platinum-based Chemotherapy

Cisplatin DRUG

Cisplatin will be administered intravenously once every 3 weeks. Cisplatin treatment will be administered for up to 4 cycles.

Tislelizumab in Combination with Platinum-based Chemotherapy

Etoposide DRUG

Etoposide will be administered intravenously once every 3 weeks. Etoposide treatment will be administered for up to 4 cycles.

Tislelizumab in Combination with Platinum-based Chemotherapy

QLC5508 DRUG

QLC5508 will be administered intravenously once every 3 weeks. Treatment will continue until disease progression or unacceptable toxicity, whichever occurs first.

QLC5508 in combination with QL2107

Eligibility Criteria

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

You may qualify if:

• Age ≥18 years.
• Participants with histologically or cytologically confirmed Extensive-Stage Small Cell Lung Cancer (ES-SCLC) per the Veterans Administration Lung Cancer Study Group (VALG) staging system.
• No prior systemic treatment for ES-SCLC.
• At least one extracranial measurable lesion according to RECIST v1.1.
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, without deterioration within 2 weeks prior to the first dose of study treatment.
• Life expectancy ≥12 weeks.
• Has adequate organ function.
• Male and female participants of reproductive/childbearing potential must agree to avoid pregnancy.
• Voluntarily sign the written informed consent form and comply with the protocol requirements.

You may not qualify if:

• Has received or undergoing any of the following treatment:
• Previous or current treatment with B7-H3 targeted therapy. Previous or current treatment with topoisomerase I inhibitors.
• Participants with transformed Non-Small Cell Lung Cancer (NSCLC), epidermal growth factor receptor (EGFR) mutation-positive NSCLC that has transformed to SCLC, or mixed SCLC-NSCLC histology.
• Presence with active brain metastases, leptomeningeal metastasis, brainstem metastasis or spinal cord compression.
• Radiotherapy with a limited field of radiation within 2 weeks prior to the study treatment; more than 30% of the bone marrow irradiation or large-scale radiotherapy within 4 weeks prior to study treatment.
• Major surgery within 4 weeks prior to the study treatment.
• Unresolved AEs ≥ Grade 2 (CTCAE v6.0) from prior therapy.
• Previous or concurrent primary malignancies.
• History of severe heart disease or cerebrovascular disease.
• History of Severe or uncontrolled hypertension or diabetes mellitus.
• Severe infection within 4 weeks prior to study treatment; or uncontrolled active infection at screening.
• Known or suspected interstitial lung disease/non-infectious pneumonitis; or other moderate to severe pulmonary diseases that significantly impair respiratory function and may interfere with the detection or management of drug-related pulmonary toxicity.
• Known history of pre-existing or newly diagnosed autoimmune disease.
• History of severe neuropathy or mental disorders.
• History of severe hypersensitivity reaction, severe infusion reaction or idiosyncrasy to drugs chemically related to study drugs or any components of the study drugs.

Sponsors & Collaborators

• Qilu Pharmaceutical Co., Ltd.: lead

MeSH Terms

Conditions

Small Cell Lung Carcinoma

Interventions

tislelizumab; Carboplatin; Cisplatin; Etoposide

Condition Hierarchy (Ancestors)

Carcinoma, Bronchogenic; Bronchial Neoplasms; Lung Neoplasms; Respiratory Tract Neoplasms; Thoracic Neoplasms; Neoplasms by Site; Neoplasms; Lung Diseases; Respiratory Tract Diseases

Intervention Hierarchy (Ancestors)

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

Central Study Contacts

Haiying Yu, Bachelor

CONTACT

+86-17821799566; haiying.yu@qilu-pharma.com

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 30, 2026
• First Posted: September 3, 2026
• Study Start (Estimated): October 15, 2026
• Primary Completion (Estimated): March 15, 2029
• Study Completion (Estimated): June 15, 2030
• Last Updated: September 3, 2026

Record last verified: 2026-08