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

Roche

Status and phase: Completed; Phase 3

Conditions: Small Cell Lung Carcinoma

Treatments: Drug: Atezolizumab (MPDL3280A), an engineered anti-PD-L1 antibody; Drug: Placebo; Drug: Carboplatin; Drug: Etoposide

Study type: Interventional

Funder types: Industry

Identifiers

NCT02763579

GO30081

2015-004861-97 (EudraCT Number)

Details and patient eligibility

About

This randomized, Phase I/III, multicenter, double-blinded, placebo-controlled study was 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.

Enrollment: 503 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Histologically or cytologically confirmed ES-SCLC (per the Veterans Administration Lung Study Group [VALG] staging system)
• No prior systemic treatment for ES-SCLC
• Eastern Cooperative Oncology Group performance status of 0 or 1
• Measurable disease, as defined by RECIST v1.1
• Adequate hematologic and end organ function
• Treatment-free for at least 6 months since last chemo/radiotherapy, among those treated (with curative intent) with prior chemo/radiotherapy for limited-stage SCLC

Exclusion criteria

• Active or untreated central nervous system (CNS) metastases as determined by computed tomography (CT) or magnetic resonance imaging (MRI) evaluation
• Malignancies other than SCLC within 5 years prior to randomization, with the exception of those with a negligible risk of metastasis or death treated with expected curative outcome
• Pregnant or lactating women
• History of autoimmune disease
• History of idiopathic pulmonary fibrosis, organizing pneumonia, drug-induced pneumonitis, idiopathic pneumonitis, or evidence of active pneumonitis on screening chest CT scan. History of radiation pneumonitis in the radiation field (fibrosis) is permitted.
• Positive test result for human immunodeficiency virus (HIV)
• Active hepatitis B or hepatitis C
• Severe infections at the time of randomization
• Significant cardiovascular disease
• Prior treatment with cluster of differentiation (CD) 137 agonists or immune checkpoint blockade therapies, anti-programmed death-1 (PD-1), and anti-PD-L1 therapeutic antibody
• History of severe (or known) hypersensitivity to chimeric or humanized antibodies or fusion proteins or any component of atezolizumab formulation.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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503 participants in 2 patient groups

Atezolizumab + Carboplatin + Etoposide

Experimental group

Description:

Participants received intravenous infusions of atezolizumab 1200 milligrams (mg) in combination with carboplatin to achieve an initial target area under the concentration-time curve (AUC) of 5 milligrams per milliliter per minute (mg/mL/min) followed by etoposide 100 milligrams per square meter (mg/m\^2) on Day 1 of every 21-day cycle during the induction phase (Cycles 1-4). On Days 2 and 3 of every 21-day cycle during the induction phase (Cycles 1-4), etoposide 100 mg/m\^2 was administered alone. Thereafter, participants received maintenance (Cycle 5 onward) atezolizumab 1200 mg on Day 1 of every 21-day cycle until persistent radiographic PD, symptomatic deterioration, intolerable toxicity, withdrawal of consent, death, or study termination by the Sponsor.

Treatment:

Drug: Carboplatin

Drug: Atezolizumab (MPDL3280A), an engineered anti-PD-L1 antibody

Drug: Etoposide

Placebo + Carboplatin + Etoposide

Active Comparator group

Description:

Participants received intravenous infusions of placebo in combination with carboplatin to achieve an initial target AUC of 5 mg/mL/min followed by etoposide 100 mg/m\^2 on Day 1 of every 21-day cycle during the induction phase (Cycles 1-4). On Days 2 and 3 of every 21-day cycle during the induction phase (Cycles 1-4), etoposide 100 mg/m\^2 was administered alone. Thereafter, participants received maintenance (Cycle 5 onward) placebo on Day 1 of every 21-day cycle until persistent radiographic PD, symptomatic deterioration, intolerable toxicity, withdrawal of consent, death, or study termination by the Sponsor.

Treatment:

Drug: Carboplatin

Drug: Placebo

Drug: Etoposide