PFS as assessed by IRC per Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1) was defined as the time from randomization to the date of the first documented tumor progression, or death due to any cause, whichever occurred earlier.

Part 1 participants only

PFS as assessed by IRC per RECIST 1.1 was defined as the time from randomization to the date of the first documented tumor progression, or death due to any cause, whichever occurred earlier.

Part 2 participants only

ORR as assessed by IRC per RECIST 1.1 was defined as the percentage of participants with a best overall response (BOR) of confirmed complete response (CR) or partial response (PR).

Part 1 participants only

ORR as assessed by IRC per RECIST 1.1 was defined as the percentage of participants with a BOR of confirmed CR or PR.

Part 2 participants only

DoR was defined as the time from date of first documented response of CR or PR to the date of first documented progressive disease (PD) or death due to any cause, whichever occurred earlier.

Part 1 participants with confirmed CR or PR only. Overall number of participants analyzed = number of participants with evaluable data for the outcome measure

DoR was defined as the time from date of first documented response of CR or PR to the date of first documented PD or death due to any cause, whichever occurred earlier.

Part 2 participants with confirmed CR or PR only. Overall number of participants analyzed = number of participants with evaluable data for the outcome measure

BOR was defined as the best overall response as determined by the IRC per RECIST 1.1, between the date of randomization and the date of first documented tumor progression or the date of subsequent anti-cancer therapy, whichever occurred earlier.

Part 1 participants only

BOR was defined as the best overall response as determined by the IRC per RECIST 1.1, between the date of randomization and the date of first documented tumor progression or the date of subsequent anti-cancer therapy, whichever occurred earlier.

Part 2 participants only

TEAEs were AEs that developed or worsened during the on-treatment period and any treatment-related AEs that occurred during the post-treatment period but prior to start of another anti-cancer systemic therapy.

Randomized and treated Part 1 participants only

TEAEs were AEs that developed or worsened during the on-treatment period and any treatment-related AEs that occurred during the post-treatment period but prior to start of another anti-cancer systemic therapy.

Randomized and treated Part 2 participants only

Part 1 only

Only the first 10 participants enrolled in the Cemiplimab+AbbrevChemo+ipilimumab arm were DLT evaluable, defined as the participants who completed the DLT observation period and those participants who discontinued early due to the development of a DLT. The participants were analyzed as treated.

Serious TEAEs were defined as medically significant but not immediately life-threatening AEs that developed or worsened during the on-treatment period and any treatment-related AEs that occurred during the post-treatment period but prior to start of another anti-cancer systemic therapy.

Randomized and treated Part 1 participants only

Serious TEAEs were defined as medically significant but not immediately life-threatening AEs that developed or worsened during the on-treatment period and any treatment-related AEs that occurred during the post-treatment period but prior to start of another anti-cancer systemic therapy.

Randomized and treated Part 2 participants only

The on-treatment period was defined as the day from the first dose of study drug to the day of the last dose of study drug plus 90 days or 1 day before participants receive their first dose of new anti-cancer systemic therapy, whichever is earlier.

Randomized and treated Part 1 participants only

The on-treatment period was defined as the day from the first dose of study drug to the day of the last dose of study drug plus 90 days or 1 day before participants receive their first dose of new anti-cancer systemic therapy, whichever is earlier.

Randomized and treated Part 2 participants only

OS rate at a landmark (12, 18, and 24 months) was defined as the Kaplan-Meier (K-M) estimated probability of participants who survived due to any cause at the landmark after randomization.

Part 1 participants only

OS rate at a landmark (12, 18, and 24 months) was defined as the K-M estimated probability of participants who survived due to any cause at the landmark after randomization.

Part 2 participants only

The EORTC QLQ-C30 is a 30-item questionnaire used to assess the overall quality of life (QoL) in cancer participants. It consists of 15 domains: 1 Global Health Status (GHS)/QoL scale, 5 functional scales (Physical, role, cognitive, emotional, social), 9 symptom scales/items (Fatigue, nausea and vomiting, pain, dyspnea, sleep disturbance, appetite loss, constipation, diarrhea, financial impact). Reported here are the EORTC QLQ-C30 GHS/QoL scores only. GHS/QoL is derived from two items-"How would you rate your overall health during the past week?" and "How would you rate your overall quality of life during the past week?"-each scored from 1 (very poor) to 7 (excellent). The average of these two items is linearly transformed to a 0-100 scale; higher scores indicate better overall quality of life, and a positive change from baseline reflects improvement.

Includes only participants in part 1 with both baseline and at least one post-baseline value. Overall number of participants analysed = participants evaluable for the outcome measure. Number analyzed = participants evaluable at the specified timepoint

OS was defined as the time from randomization to the date of death due to any cause.

Part 1 participants only

OS was defined as the time from randomization to the date of death due to any cause.

Part 2 participants only

The EORTC QLQ-C30 is a 30-item questionnaire used to assess the overall QoL in cancer participants. It consists of 15 domains: 1 Global Health Status (GHS)/QoL scale, 5 functional scales (Physical, role, cognitive, emotional, social), 9 symptom scales/items (Fatigue, nausea and vomiting, pain, dyspnea, sleep disturbance, appetite loss, constipation, diarrhea, financial impact). Reported here are the EORTC QLQ-C30 GHS/QoL scores only. GHS/QoL is derived from two items-"How would you rate your overall health during the past week?" and "How would you rate your overall quality of life during the past week?"-each scored from 1 (very poor) to 7 (excellent). The average of these two items is linearly transformed to a 0-100 scale; higher scores indicate better overall quality of life, and a positive change from baseline reflects improvement.

Includes only participants in part 2 with both baseline and at least one post-baseline value. Overall number of participants analysed = participants evaluable for the outcome measure. Number analyzed = participants evaluable at the specified timepoint