DFS is the time from the date of randomization until the first day non-small cell lung cancer (NSCLC) relapse is documented by radiological exam and/or biopsy, or until death in the absence of relapse. After randomization, NSCLC relapse was based on radiological evidence or biopsy, as determined by the investigator. Participants without a DFS event were censored on the last adequate radiological assessment date.

Randomized cohort full analysis set (all randomized participants).

Overall survival was defined as the time from the date of randomization until the documented date of death. Participants who were still alive were censored on the last day they were known to be alive.

Randomized cohort full analysis set

Overall survival was defined as the time from the date of randomization until the documented date of death. Participants who were still alive were censored on the last day they were known to be alive.

Randomized cohort full analysis set

Disease-free survival (DFS) is the time from the date of randomization until the first day NSCLC relapse is documented by radiological exam and/or biopsy, or until death in the absence of relapse. After randomization, NSCLC relapse was based on radiological evidence or biopsy, as determined by the investigator. Participants without a DFS event were censored on the last adequate radiological assessment date. Activating EGFR mutation-positive is defined as exon 19 deletion or exon 21 L858R (or both) detected.

Randomized cohort full analysis set participants who are EGFR mutation positive

Disease-free survival (DFS) is the time from the date of randomization until the first day NSCLC relapse is documented by radiological exam and/or biopsy, or until death in the absence of relapse. After randomization, NSCLC relapse was based on radiological evidence or biopsy, as determined by the investigator. Participants without a DFS event were censored on the last adequate radiological assessment date. Activating EGFR mutation-positive is defined as exon 19 deletion or exon 21 L858R (or both) detected.

Randomized cohort full analysis set participants who are EGFR mutation positive

DFS is the time from the date of randomization until the first day that non-small cell lung cancer (NSCLC) relapse is documented by radiological exam and/or biopsy, or until death in the absence of relapse. After randomization, NSCLC relapse was based on radiological evidence or biopsy, as determined by the investigator. Participants without a DFS event were censored on the last adequate radiological assessment date.

Randomized cohort full analysis set (all randomized participants).

Overall survival is defined as the time from the date of randomization until the documented date of death. Participants who were still alive were censored on the last day they were known to be alive.

Activating EGFR mutation-positive is defined as exon 19 deletion or exon 21 L858R (or both) detected.

Randomized cohort full analysis participants who were EGFR mutation positive

Overall survival is defined as the time from the date of randomization until the documented date of death. Participants who were still alive were censored on the last day they were known to be alive.

Activating EGFR mutation-positive is defined as exon 19 deletion or exon 21 L858R (or both) detected.

Randomized cohort full analysis participants who were EGFR mutation positive

An AE was defined as any untoward medical occurrence in a study participant and did not necessarily have a causal relationship with study treatment.

An AE was considered serious if it resulted in death, a life-threatening situation, inpatient hospitalization or prolongation of existing hospitalization, persistent or significant disability/incapacity, congenital anomaly/birth defect in the offspring of a participant, other important medical events, or is on the Astellas Always Serious List.

A drug-related AE was any AE with at least a possible relationship to study treatment as assessed by the investigator. Severity was graded by the investigator according to the National Cancer Institute Common Terminology Criteria for Adverse Events, v3.0, where Grade 1=Mild AE; Grade=2 Moderate AE; Grade 3=Severe AE; Grade 4=Life-threatening or disabling; Grade 5=Death related to AE. AEs leading to death include deaths that occurred more than 30 days after the last dose of study drug.

Randomized Cohort, safety analysis set: all randomized participants who received at least one dose of study drug. One participant in the Randomized Cohort assigned to the erlotinib arm received placebo instead due to a dispensing error and is included in the placebo group for safety analyses.