Study of Platinum Plus Etoposide With or Without Tislelizumab in Participants With Untreated Extensive-Stage Small Cell Lung Cancer

Defined as the time from the date of randomization to the date of death due to any cause. Median OS was estimated using Kaplan-Meier methodology.

Time frame: From randomization to the primary completion cut-off on April 19, 2023, the median follow-up was 15.44 months (range: 0.2-44.9) for Arm A and 13.22 months (range: 0.1-40.8) for Arm B.

Population: Intent to treat analysis set

Change from baseline in EORTC QLQ-CL13 scores for coughing, dysphagia, and chest pain. The EORTC QLQ-LC13 is a questionnaire that measures lung cancer-specific disease and treatment symptoms. It includes questions about specific symptoms in which participants respond based on a 4-point scale, where 1 is not at all and 4 is very much. Raw scores are transformed into a 0 to 100 scale via linear transformation. A lower score indicates an improvement in symptoms.

Time frame: Baseline to Cycles 4 and 6 ( Each cycle was 21 days)

Population: HRQoL analysis set. Only participants with data at both baseline and corresponding post-baseline visit are included in the analysis at each time point.

The EORTC QLQ-30 contains 30 questions that incorporate 5 functional scales (physical functioning, role functioning, emotional functioning, cognitive functioning, and social functioning), 1 global health status scale, 3 symptom scales (fatigue, nausea and vomiting, and pain), and 6 single items (dyspnea, insomnia, appetite loss, constipation, diarrhea, and financial difficulties). The participant answers questions about their health during the past week. There are 28 questions answered on a 4-point scale where 1 = Not at all (best) and 4 = Very Much (worst) and 2 global health quality of life (QOL) questions answered on a 7-point scale where 1 = Very poor and 7 = Excellent. Raw scores are transformed into a 0 to 100 scale via linear transformation. Higher scores in GHS and functional scales indicate better quality of life.

Time frame: Baseline to Cycles 4 and 6 ( Each cycle was 21 days)

Population: The HRQoL analysis set included all randomized participants who received any dose of study drug and completed at least one HRQoL assessment. Only participants with data at both baseline and corresponding post-baseline visit are included in the analysis at each time point.

Defined as the percentage of participants whose best overall response (BOR) is complete response, partial response, or durable stable disease (stable disease for at least 24 weeks) per RECIST v1.1.

Time frame: From randomization to the primary completion cut-off on April 19, 2023, the median follow-up was 15.44 months (range: 0.2-44.9) for Arm A and 13.22 months (range: 0.1-40.8) for Arm B.

Population: Intent to treat analysis set

Defined as the percentage of participants whose best overall response (BOR) is complete response, partial response, or stable disease per RECIST v1.1. Stable Disease: Neither sufficient shrinkage of target lesions to qualify for PR nor sufficient increase to qualify for progressive disease, persistence of one or more non-target lesion(s) and/or maintenance of tumor marker level above the normal limits, and no new lesions.

Time frame: From randomization to the primary completion cut-off on April 19, 2023, the median follow-up was 15.44 months (range: 0.2-44.9) for Arm A and 13.22 months (range: 0.1-40.8) for Arm B.

Population: Intent to treat analysis set

Defined as the time from the first occurrence of a documented objective response to the time of relapse, as determined by the investigator per RECIST v1.1, or death from any cause, whichever comes first. Median DOR was estimated using Kaplan-Meier methodology.

Time frame: From randomization to the primary completion cut-off on April 19, 2023, the median follow-up was 15.44 months (range: 0.2-44.9) for Arm A and 13.22 months (range: 0.1-40.8) for Arm B.

Population: Intent to treat analysis Set. Only participants with best overall response of complete response or partial response confirmed per RECIST v1.1 were included in the analysis, and percentages were based on the number of responders

Number of participants with treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs) graded according to the National Cancer Institute-Common Terminology Criteria for Adverse Events (NCI-CTCAE) version 5.0.

Time frame: From the first dose to 30 days after the last dose or final cutoff on December 29, 2023, maximum treatment exposure was 232 weeks for Arm A and 157 weeks for Arm B.

Population: The Safety Analysis Set includes all participants randomized and received any dose of any study drug.

Orr is defined as the percentage of participants who had partial response or complete response as determined by the investigator per RECIST v1.1 in all randomized patients with measurable disease at baseline. Complete Response (CR): Disappearance of all target and non-target lesions and no new lesions. Any pathological lymph nodes (whether target or non-target) must have reduction in short axis to \< 10 mm. Partial Response (PR): At least a 30% decrease in the sum of diameters of target lesions with no progression of non-target lesions and no new lesions, or disappearance of all target lesions with persistence of one or more non-target lesion(s) and/or maintenance of tumor marker level above the normal limits and no new lesions.

Time frame: From randomization to the primary completion cut-off on April 19, 2023, the median follow-up was 15.44 months (range: 0.2-44.9) for Arm A and 13.22 months (range: 0.1-40.8) for Arm B.

Population: Intent to treat analysis set

Defined as the time from randomization to the first objectively documented disease progression, or death from any cause, whichever occurred first, as assessed by the investigator per the Response Evaluation Criteria in Solid Tumors (RECIST) v1.1. Kaplan-Meier methodology was used to estimate the median PFS. Progressive Disease (PD): At least a 20% increase in the size of target lesions, with an absolute increase of at least 5 mm, or unequivocal progression of existing non-target lesions, or any new lesions.

Time frame: From randomization to the primary completion cut-off on April 19, 2023, the median follow-up was 15.44 months (range: 0.2-44.9) for Arm A and 13.22 months (range: 0.1-40.8) for Arm B.

Population: Intent to treat analysis set

Time to deterioration is defined as the time from randomization to the first confirmed worsening score or death. Clinically meaningful deterioration is defined as a ≥10-point decrease from baseline in QLQ-C30 physical functioning and a ≥10-point increase in QLQ-LC13 coughing and chest pain scores. If a participant did not have an event (death or deterioration), they were censored at their last clinic visit at which corresponding score was measured. Median TTD was estimated using Kaplan-Meier methodology.

Time frame: From randomization to the primary completion data cut-off on April 19, 2023, the median follow-up was 15.44 months (range: 0.2-44.9) for Arm A and 13.22 months (range: 0.1-40.8) for Arm B.

Population: HRQoL analysis set