Trial Outcomes & Findings for A Study of the Efficacy and Safety of Atezolizumab Plus Chemotherapy for Patients With Early Relapsing Recurrent Triple-Negative Breast Cancer (NCT NCT03371017)

Last Updated: 2025-11-12

Results Overview

OS was defined as time from randomization to death from any cause. Participants without a reported death event at the time of the analysis were censored on the date they were last known to be alive. If no post-baseline data were available, OS was censored at the date of randomization +1 day.

Recruitment status

COMPLETED

Study phase

PHASE3

Target enrollment

595 participants

Primary outcome timeframe

Time from randomization to death (Up to 68 months)

Results posted on

2025-11-12

Participant Flow

A total of 595 participants with inoperable locally advanced or metastatic Triple-negative Breast Cancer (TNBC) took part in the study at 126 investigative sites in 28 countries from 11 January 2018 to 23 October 2024.

Participants were randomized in a 1:1 ratio to receive atezolizumab with chemotherapy or placebo with chemotherapy.

Participant milestones

Participant milestones
Measure	Placebo + Chemotherapy Participants received atezolizumab matching placebo by intravenous (IV) infusion on Day 1 of each cycle along with either gemcitabine, 1000 milligrams per square meter (mg/m\^2), followed by carboplatin target under the curve (AUC) 2 milligrams per milliliter per minute (mg/ml/min), both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, twice daily (BID), orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until disease progression (PD), unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy Participants received atezolizumab 1200 milligrams (mg), by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
Overall Study STARTED	298	297
Overall Study Safety-evaluable Population	294	293
Overall Study Programmed Death-ligand 1 (PD-L1)-Positive Population	177	177
Overall Study Modified Intent-to-Treat (mITT) Population	192	188
Overall Study COMPLETED	0	0
Overall Study NOT COMPLETED	298	297

Reasons for withdrawal

Reasons for withdrawal
Measure	Placebo + Chemotherapy Participants received atezolizumab matching placebo by intravenous (IV) infusion on Day 1 of each cycle along with either gemcitabine, 1000 milligrams per square meter (mg/m\^2), followed by carboplatin target under the curve (AUC) 2 milligrams per milliliter per minute (mg/ml/min), both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, twice daily (BID), orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until disease progression (PD), unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy Participants received atezolizumab 1200 milligrams (mg), by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
Overall Study Physician Decision	0	1
Overall Study Reason not Specified	0	1
Overall Study Lost to Follow-up	13	16
Overall Study Death	228	215
Overall Study Withdrawal by Subject	20	25
Overall Study Study Ended by Sponsor	37	38
Overall Study Protocol Deviation	0	1

Baseline Characteristics

A Study of the Efficacy and Safety of Atezolizumab Plus Chemotherapy for Patients With Early Relapsing Recurrent Triple-Negative Breast Cancer

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Placebo + Chemotherapy n=298 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=297 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Total n=595 Participants Total of all reporting groups
Age, Continuous	49.4 years STANDARD_DEVIATION 11.7 • n=10 Participants	48.6 years STANDARD_DEVIATION 10.9 • n=10 Participants	49.0 years STANDARD_DEVIATION 11.3 • n=20 Participants
Sex: Female, Male Female	298 Participants n=10 Participants	297 Participants n=10 Participants	595 Participants n=20 Participants
Sex: Female, Male Male	0 Participants n=10 Participants	0 Participants n=10 Participants	0 Participants n=20 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	59 Participants n=10 Participants	51 Participants n=10 Participants	110 Participants n=20 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	222 Participants n=10 Participants	218 Participants n=10 Participants	440 Participants n=20 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	17 Participants n=10 Participants	28 Participants n=10 Participants	45 Participants n=20 Participants
Race (NIH/OMB) American Indian or Alaska Native	3 Participants n=10 Participants	5 Participants n=10 Participants	8 Participants n=20 Participants
Race (NIH/OMB) Asian	66 Participants n=10 Participants	69 Participants n=10 Participants	135 Participants n=20 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=10 Participants	0 Participants n=10 Participants	0 Participants n=20 Participants
Race (NIH/OMB) Black or African American	10 Participants n=10 Participants	9 Participants n=10 Participants	19 Participants n=20 Participants
Race (NIH/OMB) White	199 Participants n=10 Participants	184 Participants n=10 Participants	383 Participants n=20 Participants
Race (NIH/OMB) More than one race	0 Participants n=10 Participants	2 Participants n=10 Participants	2 Participants n=20 Participants
Race (NIH/OMB) Unknown or Not Reported	20 Participants n=10 Participants	28 Participants n=10 Participants	48 Participants n=20 Participants

PRIMARY outcome

Timeframe: Time from randomization to death (Up to 68 months)

Population: PD-L1 positive population included all participants randomized in the study whose PD-L1 status was tumor-infiltrating IC of 1% or greater (IC1/2/3) at the time of randomization, grouped according to their assigned treatment arm, whether or not the assigned study treatment was received.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=177 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=177 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
Overall Survival (OS) in PD-L1-positive Population	11.24 months Interval 9.0 to 13.31	12.09 months Interval 10.12 to 15.08

PRIMARY outcome

Timeframe: Time from randomization to death (Up to 68 months)

Population: mITT population included all participants randomized under the protocol versions prior to version 4.0 (referred to as all-comers, i.e., PD-L1(SP142)-positive and PD-L1(SP142)-negative participants, grouped according to their assigned treatment arm, whether or not the assigned study treatment was received.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=192 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=188 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
OS in Modified Intent-to-treat (mITT) Population	9.79 months Interval 8.44 to 11.96	10.35 months Interval 8.9 to 12.88

SECONDARY outcome

Timeframe: 12 months

12-month survival rate was defined as the percentage of participants alive 12 months after randomization. The 12-month survival rates were estimated by Kaplan-Meier methodology. Percentages have been rounded off to the nearest whole number.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=177 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=177 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
12-month Survival Rate in PD-L1-positive Population	47.58 percentage of participants Interval 39.92 to 55.23	50.26 percentage of participants Interval 42.61 to 57.91

SECONDARY outcome

Timeframe: 12 months

Population: mITT population included all participants randomized under the protocol versions prior to version 4.0 (referred to as all-comers, i.e., PD-L1(SP142)-positive and PD-L1(SP142)-negative participants), grouped according to their assigned treatment arm, whether or not the assigned study treatment was received.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=192 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=188 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
12-month Survival Rate in mITT Population	42.44 percentage of participants Interval 35.23 to 49.66	46.20 percentage of participants Interval 38.84 to 53.56

SECONDARY outcome

Timeframe: 18 months

18-month survival rate was defined as the percentage of participants alive 18 months after randomization. The 18-month survival rates were estimated by Kaplan-Meier methodology. Percentages have been rounded off to nearest whole number.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=177 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=177 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
18-month Survival Rate in PD-L1-positive Population	32.48 percentage of participants Interval 25.07 to 39.89	33.63 percentage of participants Interval 26.05 to 41.21

SECONDARY outcome

Timeframe: 18 months

Population: mITT population included all participants randomized under the protocol versions prior to version 4.0 (referred to as all-comers, i.e., PD-L1(SP142)-positive and PD-L1(SP142)-negative participants), grouped according to their assigned treatment arm, whether or not the assigned study treatment was received.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=192 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=188 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
18-month Survival Rate in mITT Population	25.68 percentage of participants Interval 19.15 to 32.21	27.05 percentage of participants Interval 20.39 to 33.71

SECONDARY outcome

Timeframe: Time from randomization to the first occurrence of PD or death (Up to 68 months)

PFS was defined as the time from randomization to the first occurrence of PD, as determined by the investigator according to Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1), or death from any cause, whichever occurs first. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum of diameters at prior timepoints (including baseline). In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of ≥5 millimeters (mm). Data for participants not experiencing PD or death were censored at the last tumour assessment date. If no tumor assessment was performed after randomisation, data were censored at the date of randomisation +1 day.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=177 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=177 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
Progression-free Survival (PFS) in PD-L1-positive Population	3.58 months Interval 3.35 to 4.17	4.21 months Interval 3.71 to 5.62

SECONDARY outcome

Timeframe: Time from randomization to the first occurrence of PD or death (Up to 68 months)

Population: mITT population included all participants randomized under the protocol versions prior to version 4.0 (referred to as all-comers, i.e., PD-L1(SP142)-positive and PD-L1(SP142)-negative participants), grouped according to their assigned treatment arm, whether or not the assigned study treatment was received.

PFS was defined as the time from randomization to the first occurrence of PD, as determined by the investigator according to RECIST v1.1, or death from any cause, whichever occurs first. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum of diameters at prior timepoints (including baseline). In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of ≥5 mm. Data for participants not experiencing PD or death were censored at the last tumour assessment date. If no tumor assessment was performed after randomisation, data were censored at the date of randomisation +1 day.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=192 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=188 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
PFS in mITT Population	3.58 months Interval 3.06 to 3.81	3.71 months Interval 2.83 to 4.01

SECONDARY outcome

Timeframe: Baseline up to end of study (Up to 68 months)

ORR was defined as percentage of participants with measurable disease at baseline who achieved a documented unconfirmed objective response (OR). OR was defined as either a complete response (CR) or a partial response (PR), as determined by the investigator according to RECIST v1.1. CR was defined as the disappearance of all target lesions. Any pathological lymph nodes must have a reduction in short axis to \<10 millimeters (mm). PR was defined as at least a 30% decrease in the sum of diameters (SOD) of target lesions, taking as reference the baseline SOD, in the absence of CR. Percentages have been rounded off to nearest whole number.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=159 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=154 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
Objective Response Rate (ORR) in Response-evaluable Population, Subset of PD-L1-positive Population	28.3 percentage of participants Interval 21.45 to 35.98	39.6 percentage of participants Interval 31.83 to 47.8

SECONDARY outcome

Timeframe: Baseline up to end of study (Up to 68 months)

Population: mITT population included all participants randomized under the protocol versions prior to version 4.0 (referred to as all-comers, i.e., PD-L1 (SP142)-positive and PD-L1 (SP142)-negative participants), grouped according to their assigned treatment arm, whether or not the assigned study treatment was received. Response-evaluable Population included participants randomized in the study with measurable disease at baseline.

ORR was defined as percentage of participants with measurable disease at baseline who achieved a documented unconfirmed OR. OR was defined as either a CR or PR, as determined by the investigator according to RECIST v1.1. CR was defined as the disappearance of all target lesions. Any pathological lymph nodes must have a reduction in short axis to \<10 mm. PR was defined as at least a 30% decrease in the SOD of target lesions, taking as reference the baseline SOD, in the absence of CR. Percentages have been rounded off to nearest whole number.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=168 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=171 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
ORR in Response-evaluable Population, Subset of mITT Population	32.1 percentage of participants Interval 25.16 to 39.77	31.0 percentage of participants Interval 24.16 to 38.51

SECONDARY outcome

Timeframe: Time from the first occurrence of a documented OR until the date of PD/death (Up to 68 months)

DoR was defined as the time from the first occurrence of a documented unconfirmed response (CR or PR) until the date of PD as determined by the investigator from tumor assessments using RECIST v1.1 or death from any cause, whichever occurs first. CR was defined as the disappearance of all target lesions. Any pathological lymph nodes must have a reduction in short axis to \<10 mm. PR was defined as at least a 30% decrease in the SOD of target lesions, taking as reference the baseline SOD, in the absence of CR. PD was defined as at least a 20% increase in the SOD of target lesions, taking as reference the smallest sum on study, including baseline, in addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. The appearance of one or more new lesions was also considered progression.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=45 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=61 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
Duration of Objective Response (DoR) in DoR-evaluable Population Subset of PD-L1-positive Population	4.14 months Interval 3.45 to 5.78	6.60 months Interval 4.63 to 8.02

SECONDARY outcome

Timeframe: Time from the first occurrence of a documented OR until the date of PD/death (Up to 68 months)

Population: mITT population included all participants randomized under the protocol versions prior to version 4.0 (referred to as all-comers, i.e., PD-L1(SP142)-positive and PD-L1(SP142)-negative participants), grouped according to their assigned treatment arm, whether or not the assigned study treatment was received. DOR-evaluable population included participants randomized in the study with measurable disease at baseline and an OR.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=54 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=53 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
DoR in DoR-evaluable Population Subset of mITT Population	5.22 months Interval 3.81 to 6.6	5.70 months Interval 4.17 to 7.92

SECONDARY outcome

Timeframe: Up to 68 months

Population: PD-L1 positive population included all participants randomized in the study whose PD-L1 status was tumor-infiltrating immune cells IC of 1% or greater (IC1/2/3) at the time of randomization, grouped according to their assigned treatment arm, whether or not the assigned study treatment was received. Response-evaluable population included participants randomized in the study with measurable disease at baseline.

CBR was defined as the percentage of participants with either an unconfirmed CR or PR or stable disease (SD) that lasts at least 6 months as determined by the investigator according to RECIST v1.1. CR was defined as the disappearance of all target lesions. Any pathological lymph nodes must have a reduction in short axis to \<10 mm. PR was defined as at least a 30% decrease in the SOD of target lesions, taking as reference the baseline SOD, in the absence of CR. SD was defined as neither sufficient shrinkage to qualify for CR or PR nor sufficient increase to qualify for PD. PD was defined as at least a 20% increase in the SOD of target lesions, taking as reference the smallest SOD at prior timepoints (including baseline). In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of ≥5 mm. Percentages have been rounded off to nearest whole number.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=159 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=154 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
Clinical Benefit Rate (CBR) in Response-evaluable Population Subset of PD-L1-positive Population	34.6 percentage of participants Interval 27.23 to 42.53	42.9 percentage of participants Interval 34.92 to 51.07

SECONDARY outcome

Timeframe: Up to 68 months

Population: mITT population included all participants randomized under the protocol versions prior to version 4.0 (referred to as all-comers, i.e., PD-L1(SP142)-positive and PD-L1(SP142)-negative participants), grouped according to their assigned treatment arm, whether or not the assigned study treatment was received. Response-evaluable population included participants randomized in the study with measurable disease at baseline.

CBR was defined as the percentage of participants with either an unconfirmed CR or PR or SD that lasts at least 6 months as determined by the investigator according to RECIST v1.1. CR was defined as the disappearance of all target lesions. Any pathological lymph nodes must have a reduction in short axis to \<10 mm. PR was defined as at least a 30% decrease in the SOD of target lesions, taking as reference the baseline SOD, in the absence of CR. SD was defined as neither sufficient shrinkage to qualify for CR or PR nor sufficient increase to qualify for PD. PD was defined as at least a 20% increase in the SOD of target lesions, taking as reference the smallest SOD at prior timepoints (including baseline). In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of ≥5 mm. Percentages have been rounded off to nearest whole number.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=168 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=171 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
CBR in Response-evaluable Population Subset of mITT Population	36.3 percentage of participants Interval 29.04 to 44.07	35.1 percentage of participants Interval 27.96 to 42.74

SECONDARY outcome

Timeframe: Up to 68 months

C-ORR was defined as percentage of participants with measurable disease at baseline who achieved a documented confirmed OR. OR was defined as either a CR or PR, as determined by the investigator according to RECIST v1.1. CR was defined as the disappearance of all target lesions. Any pathological lymph nodes must have a reduction in short axis to \<10 mm. PR was defined as at least a 30% decrease in the SOD of target lesions, taking as reference the baseline SOD, in the absence of CR. Percentages have been rounded off to nearest whole number.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=159 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=154 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
Confirmed Objective Response Rate (C-ORR) in Response-evaluable Population Subset of PD-L1-positive Population	19.5 percentage of participants Interval 13.65 to 26.52	31.2 percentage of participants Interval 23.96 to 39.12

SECONDARY outcome

Timeframe: Up to 68 months

Population: mITT population included all participants randomized under the protocol versions prior to version 4.0 (referred to as all-comers, i.e., PD-L1(SP142)-positive and PD-L1(SP142)-negative participants), grouped according to their assigned treatment arm, whether or not the assigned study treatment was received. Response-evaluable population included participants randomized in the study with measurable disease at baseline.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=168 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=171 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
C-ORR in Response-evaluable Population Subset of mITT Population	23.2 percentage of participants Interval 17.06 to 30.34	23.4 percentage of participants Interval 17.27 to 30.46

SECONDARY outcome

Timeframe: Time from the first occurrence of a documented OR until the date of PD/death (Up to 68 months)

Population: PD-L1 population included all participants randomized in the study whose PD-L1 status was tumor-infiltrating IC of 1% or greater (IC1/2/3) at the time of randomization, grouped according to their assigned treatment arm, whether or not the assigned study treatment was received. C-DOR-evaluable population included participants randomized in the study with measurable disease at baseline and a confirmed OR.

C-DoR was defined as the time from the first occurrence of a documented confirmed response (CR or PR) until the date of PD as determined by the investigator from tumor assessments using RECIST v1.1 or death from any cause, whichever occurs first. CR was defined as the disappearance of all target lesions. Any pathological lymph nodes must have a reduction in short axis to \<10 mm. PR was defined as at least a 30% decrease in the SOD of target lesions, taking as reference the baseline SOD, in the absence of CR. PD was defined as at least a 20% increase in the SOD of target lesions, taking as reference the smallest sum on study, including baseline, in addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. The appearance of one or more new lesions was also considered progression.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=31 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=48 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
DoR for Confirmed Responders (C-DoR) in C-DoR-evaluable Population Subset of PD-L1-positive Population	5.78 months Interval 4.21 to 8.48	7.92 months Interval 6.6 to 12.78

SECONDARY outcome

Timeframe: Time from the first occurrence of a documented OR until the date of PD/death (Up to 68 months)

Population: mITT population included all participants randomized under the protocol versions prior to version 4.0 (referred to as all-comers, i.e., PD-L1(SP142)-positive and PD-L1(SP142)-negative participants), grouped according to their assigned treatment arm, whether or not the assigned study treatment was received. C-DOR-evaluable population included participants randomized in the study with measurable disease at baseline and a confirmed OR.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=39 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=40 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
C-DoR in C-DoR-evaluable Population Subset of mITT Population	6.51 months Interval 4.83 to 8.48	7.43 months Interval 5.55 to 12.98

SECONDARY outcome

Timeframe: Up to 68 months

TTD in GHS/QoL, defined by a minimally important decrease of ≥10 points at 2 consecutive assessment time-points on the GHS/QoL scale (Items 29, 30) of EORTC QLQ-C30, which consists of 30 questions that assess 5 aspects of participant functioning (physical, emotional, role, cognitive, and social), three symptom scales (fatigue, nausea and vomiting, and pain), GHS and QoL, \& six single items (dyspnea, insomnia, appetite loss, constipation, diarrhea, and financial difficulties) with a recall period of the previous week. Participant responses to questions regarding GHS (Question 29: GHS; "How would you rate your overall health during the past week?") \& QoL (Question 30: QoL; "How would you rate your overall quality of life during the past week?") were assessed \& were scored on a 7-point scale (1= Very poor; 7=Excellent). Scores are linearly transformed on a scale of 0 to 100, with a high score indicating better QoL.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=177 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=177 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
Time to Confirmed Deterioration (TTD) in Global Health Status/Quality of Life (GHS/QoL) According to the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire - Core 30 (EORTC QLQ-C30) in PD-L1-positive Population	6.77 months Interval 4.3 to 32.69	9.43 months Interval 6.01 to The upper limit of the 95% CI was not estimable due to insufficient number of participants with events.

SECONDARY outcome

Timeframe: Up to 68 months

Population: mITT population included all participants randomized under the protocol versions prior to version 4.0 (referred to as all-comers, i.e., PD-L1(SP142)-positive and PD-L1(SP142)-negative participants), grouped according to their assigned treatment arm, whether or not the assigned study treatment was received.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=192 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=188 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
TTD in GHS/QoL According to EORTC QLQ-C30 in mITT Population	7.66 months Interval 4.34 to 32.69	8.90 months Interval 5.88 to 16.82

SECONDARY outcome

Timeframe: From treatment initiation up to 90 days after last dose (up to 71 months)

Population: Safety-evaluable population included participants who received any amount of any study drug (atezolizumab/placebo or chemotherapy).

An AE is any untoward medical occurrence in a participant administered a pharmaceutical product, regardless of causal attribution. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding, for example), symptom, or disease temporally associated with the use of a pharmaceutical product, whether or not considered related to the pharmaceutical product. Preexisting conditions that worsen during a study are also considered AEs.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=294 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=293 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
Number of Participants With Adverse Events (AEs)	283 Participants	281 Participants

SECONDARY outcome

Timeframe: Pre-dose on Day 1 of Cycles 1, 2, 3 and 4; Post-dose on Day 1 of Cycles 1 and 3 and Treatment Discontinuation Visit (up to 69 months) (1 Cycle= 3 weeks)

Population: Pharmacokinetic (PK)-evaluable population included participants who received any dose of study medication and who had at least one evaluable post-baseline PK sample. Number analyzed is the number of participants with data available for analyses at the specified timepoints.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=268 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
Serum Concentration of Atezolizumab Cycle 1 Day 1 Predose	NA micrograms/millilitre (µg/mL) Geometric Coefficient of Variation NA Geometric mean \& geometric coefficient of variation were not estimable as samples were below the limit of quantification (BLQ).	—
Serum Concentration of Atezolizumab Cycle 1 Day 1 Post-dose	442 micrograms/millilitre (µg/mL) Geometric Coefficient of Variation 59.7	—
Serum Concentration of Atezolizumab Cycle 2 Day 1 Pre-dose	87.2 micrograms/millilitre (µg/mL) Geometric Coefficient of Variation 72.7	—
Serum Concentration of Atezolizumab Cycle 3 Day 1 Predose	140 micrograms/millilitre (µg/mL) Geometric Coefficient of Variation 42.9	—
Serum Concentration of Atezolizumab Cycle 3 Day 1 Postdose	517 micrograms/millilitre (µg/mL) Geometric Coefficient of Variation 47.7	—
Serum Concentration of Atezolizumab Cycle 4 Day 1 Predose	157 micrograms/millilitre (µg/mL) Geometric Coefficient of Variation 104.9	—
Serum Concentration of Atezolizumab Treatment Discontinuation	120 micrograms/millilitre (µg/mL) Geometric Coefficient of Variation 189.7	—

SECONDARY outcome

Timeframe: Cycles 1 to 4 and Treatment Discontinuation visit (up to 69 months)

Population: Safety-evaluable population included participants who received any amount of any study drug (atezolizumab/placebo or chemotherapy). Overall number analyzed included participants with data available for analysis.

Number of ADA-positive participants after drug administration was determined for participants exposed to atezolizumab. For determining post-baseline incidence, participants were considered to be ADA-positive if they were ADA-negative or had missing data at baseline but developed an ADA response following study drug exposure, or if they were ADA-positive at baseline and the titer of 1 or more post-baseline samples was at least 0.60 titer units (t.u.) greater than the baseline titer result. The sum of participants who were ADA-positive at postbaseline visits of Cycles 1 to 4 and treatment discontinuation has been reported here.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=275 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
Number of Participants With Anti-Drug Antibodies (ADAs) to Atezolizumab	20 Participants	—

SECONDARY outcome

Timeframe: Baseline up to 68 months

Population: FAS population included all participants randomized in the study, grouped according to their assigned treatment arm, whether or not the assigned study treatment was received.

Outcome measures

Outcome measures
Measure	Placebo + Chemotherapy n=298 Participants Participants received atezolizumab matching placebo, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle= 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.	Atezolizumab + Chemotherapy n=297 Participants Participants received atezolizumab 1200 mg, by IV infusion on Day 1 of each cycle along with either gemcitabine, 1000 mg/m\^2, followed by carboplatin target AUC 2 mg/ml/min, both administered by IV infusion on Days 1 and 8 of each cycle or capecitabine, 1000 mg/m\^2, BID, orally on Days 1 to 14, followed by a 7-day rest period in each cycle (1 Cycle = 3 weeks). Treatment was continued until PD, unacceptable toxicity, death or participant or investigator decision to discontinue treatment.
Number of Participants With PD-L1 Protein Expression in Screening Tumour Tissue and Post-baseline Assessment Baseline IC1/2/3- Post-baseline IC1/2/3	6 Participants	2 Participants
Number of Participants With PD-L1 Protein Expression in Screening Tumour Tissue and Post-baseline Assessment Baseline IC1/2/3- Post-baseline IC 0	0 Participants	0 Participants
Number of Participants With PD-L1 Protein Expression in Screening Tumour Tissue and Post-baseline Assessment Baseline IC0- Post-baseline IC1/2/3	0 Participants	0 Participants
Number of Participants With PD-L1 Protein Expression in Screening Tumour Tissue and Post-baseline Assessment Baseline IC0- Post-baseline IC 0	3 Participants	0 Participants

Placebo + Chemotherapy

Serious events: 57 serious events

Other events: 278 other events

Deaths: 233 deaths

Atezolizumab + Chemotherapy

Serious events: 69 serious events

Other events: 276 other events

Deaths: 226 deaths

Serious adverse events

Other adverse events

Additional Information

Medical Communications

Hoffmann-La Roche

Phone: 800 821-8590

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee The Study being conducted under this Agreement is part of the Overall Study. Investigator is free to publish in reputable journals or to present at professional conferences the results of the Study, but only after the first publication or presentation that involves the Overall Study. The Sponsor may request that Confidential Information be deleted and/or the publication be postponed in order to protect the Sponsor's intellectual property rights.
Publication restrictions are in place

Restriction type: OTHER