A Study of Carboplatin Plus Etoposide With or Without Atezolizumab in Participants With Untreated Extensive-Stage (ES) Small Cell Lung Cancer (SCLC) (IMpower133)

This randomized, Phase I/III, multicenter, double-blinded, placebo-controlled study is designed to evaluate the safety and efficacy of atezolizumab (anti-programmed death-ligand 1 [PD-L1] antibody) in combination with carboplatin plus (+) etoposide compared with treatment with placebo + carboplatin + etoposide in chemotherapy-naive participants with ES-SCLC. Participants will be randomized in a 1:1 ratio to receive either atezolizumab + carboplatin + etoposide or placebo + carboplatin + etoposide on 21-day cycles for four cycles in the induction phase followed by maintenance with atezolizumab or placebo until progressive disease (PD) as assessed by the investigator using Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST v1.1). Treatment can be continued until persistent radiographic PD or symptomatic deterioration.


Study Type: Interventional  (Clinical Trial)
Estimated Enrollment: 500 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary Purpose: Treatment
Official Title: A Phase I/III, Randomized, Double-Blind, Placebo-Controlled Study of Carboplatin Plus Etoposide With or Without Atezolizumab (Anti-PD-L1 Antibody) in Patients With Untreated Extensive-Stage Small Cell Lung Cancer
Actual Study Start Date: June 7, 2016
Estimated Primary Completion Date: August 1, 2019
Estimated Study Completion Date: August 1, 2019

Arm:
- Experimental: Atezolizumab + Carboplatin + Etoposide
- Active Comparator: Placebo + Carboplatin + Etoposide