a Study of QL1706 or QL1604 in Patients With Limited-stage Small Cell Lung Cancer After Chemoradiotherapy.

A Randomized, Double-blind Phase III Clinical Study of QL1706 Versus QL1604 as Consolidation Treatment in Patients With Limited-stage Small Cell Lung Cancer Who Have Not Experienced Disease Progression After Concurrent or Sequential Chemoradiotherapy.

The study is being conducted to evaluate the efficacy and safety of QL1706 versus QL1604 monotherapy as consolidation treatment in patients with limited-stage small cell lung cancer (LS-SCLC) who have not experienced disease progression after concurrent or sequential chemoradiotherapy.

QL1706 (Iparomlimab and Tuvonralimab) is a single bifunctional MabPair product against PD-1 and CTLA-4. QL1604 is a monoclonal antibody against PD-1.

Inclusion Criteria:

• The patient must be aged between 18 and 75 years (inclusive of boundary values), and both males and females are eligible.
• Pathologically confirmed LS-SCLC [I-III stage SCLC (any T, any N, M0)], according to the American Joint Committee on Cancer (AJCC, 8th edition) staging manual.
• Received 4 cycles of chemotherapy concurrent or sequential with radiotherapy. Chemotherapy must contain platinum and etoposide. Radiotherapy must be either total 60-70 Gy over 6 weeks for the QD regimen or total 45 Gy over 3 weeks for BID schedules.
• Patients must have achieved a complete response (CR), partial response (PR), or stable disease (SD) after receiving curative platinum-based CRT and must not have developed progressive disease (PD) prior to study entry.

Exclusion Criteria:

• Mixed SCLC and non-small cell lung cancer (NSCLC).
• Extensive-stage SCLC.
• Active or prior documented autoimmune or inflammatory disorders.
• Received other chemotherapy regimens besides etoposide and platinum-based therapy.
• Active or prior documented autoimmune or inflammatory disorders.
• Presence of interstitial lung disease or active non-infectious pneumonia (excluding grade 1 radiation pneumonitis not treated with corticosteroids).