Trial Outcomes & Findings for Study of Pembrolizumab Given Prior to Surgery and in Combination With Radiotherapy Given Post-surgery for Advanced Head and Neck Squamous Cell Carcinoma (MK-3475-689) (NCT NCT03765918)

Last Updated: 2025-08-20

Results Overview

EFS was based on Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1) as assessed by blinded independent central review (BICR) and was defined as the time from randomization to any of the following events: radiographic disease progression (RDP; participants who undergo a definitive biopsy of the progressed lesion and are found to have no histologic evidence of invasive cancer will not meet criteria for an event), RDP during the neoadjuvant phase that precluded surgery, local or distant disease progression or recurrence (as assessed with imaging or biopsy as indicated), or death due to any cause. A secondary malignancy was not considered an EFS event. Per protocol, RECIST 1.1 was modified to allow up to 10 target lesions total (up to 5 per organ). Per protocol, EFS per RECIST 1.1 as assessed by BICR in all randomized participants was presented.

Recruitment status

ACTIVE_NOT_RECRUITING

Study phase

PHASE3

Target enrollment

714 participants

Primary outcome timeframe

Up to ~66 months

Results posted on

2025-08-20

Participant Flow

Per protocol, patient-reported outcome (PRO) measures (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 \[EORTC QLQ-C30\] Global Health Status \[GHS\]/Quality of Life \[QoL\]\[Items 29 and 30\], EORTC QLQ-C30 \[Items 1-5\], EORTC QLQ-Head and Neck Module 35 \[H\&N35\] \[Items 35-38\], EORTC QLQ-H\&N35 \[Items 46, 53-54\], and EORTC QLQ-H\&N35 \[Items 31-34\] were reported separately for neoadjuvant and adjuvant treatment periods.

Two participants in the SOC arm received neoadjuvant treatment in error (protocol deviations). One of the participants (who received one cycle of neoadjuvant treatment) was included in the SOC arm for the efficacy and safety analyses per protocol. The other participant (who received 2 cycles of neoadjuvant treatment) was included in the SOC arm for efficacy analysis and in the Pembrolizumab + SOC arm for the safety analysis per protocol.

Participant milestones

Participant milestones
Measure	Pembrolizumab + Standard of Care (SOC) Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Overall Study STARTED	363	351
Overall Study Treated	360	316
Overall Study Safety Analysis Population	361	315
Overall Study Efficacy Analysis Population	363	351
Overall Study Neoadjuvant Treatment Period: Participants Who Took EORTCQLQ-C30 GHS/QoL (Items 29 & 30) Assessment	354	0
Overall Study Adjuvant Treatment Period: Participants Who Took EORTCQLQ-C30 GHS/QoL (Items 29 and 30) Assessment	356	306
Overall Study Neoadjuvant Treatment Period: Participants Who Took EORTCQLQ-C30 (Items 1-5) Assessment	354	0
Overall Study Adjuvant Treatment Period: Participants Who Took EORTCQLQ-C30 (Items 1-5) Assessment	356	306
Overall Study Neoadjuvant Treatment Period: Participants Who Took EORTCQLQ-H&N35 (Items 35-38) Assessment	354	0
Overall Study Adjuvant Treatment Period: Participants Who Took EORTCQLQ-H&N35 (Items 35-38) Assessment	356	306
Overall Study Neoadjuvant Treatment Period: Participants Who Took EORTCQLQ-H&N35 (Items 46, 53-54) Assessment	354	0
Overall Study Adjuvant Treatment Period: Participants Who Took EORTCQLQ-H&N35 (Items 46, 53-54) Assessment	356	306
Overall Study Neoadjuvant Treatment Period: Participants Who Took EORTCQLQ-H&N35 (Items 31-34) Assessment	354	0
Overall Study Adjuvant Treatment Period: Participants Who Took EORTCQLQ-H&N35 (Items 31-34) Assessment	356	306
Overall Study COMPLETED	0	0
Overall Study NOT COMPLETED	363	351

Reasons for withdrawal

Reasons for withdrawal
Measure	Pembrolizumab + Standard of Care (SOC) Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Overall Study Death	109	127
Overall Study Lost to Follow-up	2	3
Overall Study Withdrawal by Subject	12	16
Overall Study Participants Ongoing	240	205

Baseline Characteristics

Study of Pembrolizumab Given Prior to Surgery and in Combination With Radiotherapy Given Post-surgery for Advanced Head and Neck Squamous Cell Carcinoma (MK-3475-689)

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Pembrolizumab + Standard of Care (SOC) n=363 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=351 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Total n=714 Participants Total of all reporting groups
Age, Continuous	59.4 Years STANDARD_DEVIATION 10.0 • n=5 Participants	60.6 Years STANDARD_DEVIATION 10.0 • n=7 Participants	59.9 Years STANDARD_DEVIATION 10.0 • n=5 Participants
Sex: Female, Male Female	77 Participants n=5 Participants	74 Participants n=7 Participants	151 Participants n=5 Participants
Sex: Female, Male Male	286 Participants n=5 Participants	277 Participants n=7 Participants	563 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	55 Participants n=5 Participants	46 Participants n=7 Participants	101 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	300 Participants n=5 Participants	298 Participants n=7 Participants	598 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	8 Participants n=5 Participants	7 Participants n=7 Participants	15 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants
Race (NIH/OMB) Asian	51 Participants n=5 Participants	44 Participants n=7 Participants	95 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	1 Participants n=5 Participants	1 Participants n=7 Participants	2 Participants n=5 Participants
Race (NIH/OMB) Black or African American	9 Participants n=5 Participants	9 Participants n=7 Participants	18 Participants n=5 Participants
Race (NIH/OMB) White	284 Participants n=5 Participants	270 Participants n=7 Participants	554 Participants n=5 Participants
Race (NIH/OMB) More than one race	9 Participants n=5 Participants	20 Participants n=7 Participants	29 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	9 Participants n=5 Participants	6 Participants n=7 Participants	15 Participants n=5 Participants
Primary Tumor Site Oropharynx	35 Participants n=5 Participants	38 Participants n=7 Participants	73 Participants n=5 Participants
Primary Tumor Site Oral Cavity	219 Participants n=5 Participants	213 Participants n=7 Participants	432 Participants n=5 Participants
Primary Tumor Site Larynx	81 Participants n=5 Participants	73 Participants n=7 Participants	154 Participants n=5 Participants
Primary Tumor Site Hypopharynx	28 Participants n=5 Participants	26 Participants n=7 Participants	54 Participants n=5 Participants
Primary Tumor Site Missing	0 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants
Overall Cancer Staging at Baseline III	90 Participants n=5 Participants	93 Participants n=7 Participants	183 Participants n=5 Participants
Overall Cancer Staging at Baseline IVA	271 Participants n=5 Participants	257 Participants n=7 Participants	528 Participants n=5 Participants
Overall Cancer Staging at Baseline IVB	2 Participants n=5 Participants	0 Participants n=7 Participants	2 Participants n=5 Participants
Overall Cancer Staging at Baseline Missing	0 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants
Programmed Cell Death Ligand 1 (PD-L1) Status by Tumor Proportion Score (TPS) TPS <50%	257 Participants n=5 Participants	242 Participants n=7 Participants	499 Participants n=5 Participants
Programmed Cell Death Ligand 1 (PD-L1) Status by Tumor Proportion Score (TPS) TPS ≥50%	103 Participants n=5 Participants	107 Participants n=7 Participants	210 Participants n=5 Participants
Programmed Cell Death Ligand 1 (PD-L1) Status by Tumor Proportion Score (TPS) Missing	3 Participants n=5 Participants	2 Participants n=7 Participants	5 Participants n=5 Participants
PD-L1 Status by Combined Positive Score (CPS; CPS10) CPS <10	126 Participants n=5 Participants	118 Participants n=7 Participants	244 Participants n=5 Participants
PD-L1 Status by Combined Positive Score (CPS; CPS10) CPS ≥10	234 Participants n=5 Participants	231 Participants n=7 Participants	465 Participants n=5 Participants
PD-L1 Status by Combined Positive Score (CPS; CPS10) Missing	3 Participants n=5 Participants	2 Participants n=7 Participants	5 Participants n=5 Participants
PD-L1 Status by CPS (CPS1) CPS <1	13 Participants n=5 Participants	14 Participants n=7 Participants	27 Participants n=5 Participants
PD-L1 Status by CPS (CPS1) CPS ≥1	347 Participants n=5 Participants	335 Participants n=7 Participants	682 Participants n=5 Participants
PD-L1 Status by CPS (CPS1) Missing	3 Participants n=5 Participants	2 Participants n=7 Participants	5 Participants n=5 Participants

PRIMARY outcome

Timeframe: Up to ~66 months

Population: Efficacy analysis population, which included all randomized participants. Per protocol, two participants in the SOC arm received neoadjuvant treatment in error (protocol deviations) and were included in the SOC arm for efficacy analysis.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=363 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=351 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Event-free Survival (EFS)	51.8 Months Interval 37.5 to NA = upper limit not reached due to insufficient number of participants with an event.	30.4 Months Interval 21.8 to 50.1

PRIMARY outcome

Timeframe: Up to ~66 months

Population: Efficacy analysis population, which included all randomized participants with PD-L1 CPS ≥10. Per protocol, two participants in the SOC arm received neoadjuvant treatment in error (protocol deviations) and were included in the SOC arm for efficacy analysis.

EFS was based on RECIST 1.1 as assessed by BICR and was defined as the time from randomization to any of the following events: RDP (participants who undergo a definitive biopsy of the progressed lesion and are found to have no histologic evidence of invasive cancer will not meet criteria for an event), RDP during the neoadjuvant phase that precluded surgery, local or distant disease progression or recurrence (as assessed with imaging or biopsy as indicated), or death due to any cause. A secondary malignancy was not considered an EFS event. Per protocol, RECIST 1.1 was modified to allow up to 10 target lesions total (up to 5 per organ). Per protocol, EFS per RECIST 1.1 as assessed by BICR in participants with PD-L1 CPS ≥10 was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=234 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=231 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
EFS in Participants With Programmed Cell Death Ligand 1 (PD-L1) Combined Positive Score (CPS) ≥10	59.7 Months Interval 41.1 to NA = upper limit not reached due to insufficient number of participants with an event.	26.9 Months Interval 18.3 to 51.5

PRIMARY outcome

Timeframe: Up to ~66 months

Population: Efficacy analysis population, which included all randomized participants with PD-L1 CPS ≥1. Per protocol, two participants in the SOC arm received neoadjuvant treatment in error (protocol deviations) and were included in the SOC arm for efficacy analysis.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=347 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=335 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
EFS in Participants With PD-L1 CPS ≥1	59.7 Months Interval 37.9 to NA = upper limit not reached due to insufficient number of participants with an event.	29.6 Months Interval 19.5 to 41.9

SECONDARY outcome

Timeframe: Up to ~66 months

mPR rate was defined as the percentage of participants having ≤10% invasive squamous cell carcinoma within the resected primary tumor specimen and all sampled regional lymph nodes. Per protocol, mPR rate as assessed by blinded independent pathologist review (BIPR) at the time of definitive surgery in all randomized participants was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=363 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=351 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Major Pathological Response (mPR) Rate	9.4 Percentage of Participants Interval 6.6 to 12.8	0.0 Percentage of Participants Interval 0.0 to 1.0

SECONDARY outcome

Timeframe: Up to ~66 months

mPR rate was defined as the percentage of participants having ≤10% invasive squamous cell carcinoma within the resected primary tumor specimen and all sampled regional lymph nodes. Per protocol, mPR rate as assessed by BIPR at the time of definitive surgery in participants with PD-L1 CPS ≥10 was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=234 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=231 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
mPR Rate in Participants With PD-L1 CPS ≥10	13.7 Percentage of Participants Interval 9.5 to 18.8	0.0 Percentage of Participants Interval 0.0 to 1.6

SECONDARY outcome

Timeframe: Up to ~66 months

mPR rate was defined as the percentage of participants having ≤10% invasive squamous cell carcinoma within the resected primary tumor specimen and all sampled regional lymph nodes. Per protocol, mPR rate as assessed by BIPR at the time of definitive surgery in participants with PD-L1 CPS ≥1 was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=347 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=335 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
mPR Rate in Participants With PD-L1 CPS ≥1	9.8 Percentage of Participants Interval 6.9 to 13.4	0.0 Percentage of Participants Interval 0.0 to 1.1

SECONDARY outcome

Timeframe: Up to ~66 months

pCR rate was defined as the percentage of participants having no residual invasive squamous cell carcinoma within the resected primary tumor specimen and all sampled regional lymph nodes. The pCR rate as assessed by BIPR at the time of definitive surgery in all randomized participants was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=363 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=351 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Pathological Complete Response (pCR) Rate	3.0 Percentage of Participants Interval 1.5 to 5.4	0.0 Percentage of Participants Interval 0.0 to 1.0

SECONDARY outcome

Timeframe: Up to ~66 months

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=234 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=231 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
pCR Rate in Participants With PD-L1 CPS ≥10	4.3 Percentage of Participants Interval 2.1 to 7.7	0.0 Percentage of Participants Interval 0.0 to 1.6

SECONDARY outcome

Timeframe: Up to ~66 months

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=347 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=335 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
pCR Rate in Participants With PD-L1 CPS ≥1	3.2 Percentage of Participants Interval 1.6 to 5.6	0.0 Percentage of Participants Interval 0.0 to 1.1

SECONDARY outcome

Timeframe: Baseline and Week 4

Population: All randomized participants in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-C30 assessment data available for this outcome measure at Baseline and at Week 4. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

EORTC QLQ-C30 is a questionnaire to assess the overall QoL of cancer patients. Participant responses to questions regarding GHS ("How would you rate your overall health during the past week?") and QoL ("How would you rate your overall quality of life during the past week?") were scored on a 7-point scale (1= Very poor to 7=Excellent). The combined score of GHS (Item 29) and QoL (Item 30) were computed by averaging the raw scores of the 2 items and then applying a linear transformation to standardize the average score, so that the combined scores ranged from 0-100. A higher score indicated a better outcome. Per protocol, the change from baseline in GHS and QoL combined score for all randomized participants in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=352 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30) Global Health Status (GHS)/Quality of Life (QoL) (Items 29 & 30) Scale Combined Score at Week 4	2.35 Score on a scale Interval 0.2 to 4.5	—

SECONDARY outcome

Timeframe: Baseline and Week 4

Population: All randomized participants with PD-L1 CPS ≥10 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-C30 assessment data available for this outcome measure at Baseline and at Week 4. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=225 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-30 GHS/QoL (Items 29 and 30) Scale Combined Score in Participants With PD-L1 CPS ≥10 at Week 4	1.86 Score on a scale Interval -0.73 to 4.45	—

SECONDARY outcome

Timeframe: Baseline and Week 4

Population: All randomized participants with PD-L1 CPS ≥1 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-C30 assessment data available for this outcome measure at Baseline and at Week 4. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=336 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-C30 GHS/QOL (Items 29 and 30) Scale Combined Score in Participants With PD-L1 CPS ≥1 at Week 4	2.22 Score on a scale Interval 0.0 to 4.43	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-C30 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=354 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-C30 GHS/QoL (Items 29 and 30) Scale Combined Score at Week 6	-0.97 Score on a scale Interval -3.19 to 1.26	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants with PD-L1 CPS ≥10 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-C30 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=227 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-C30 GHS/QoL (Items 29 and 30) Scale Combined Score in Participants With PD-L1 CPS ≥10 at Week 6	-0.81 Score on a scale Interval -3.62 to 1.99	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants with PD-L1 CPS ≥1 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-C30 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=338 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-C30 GHS/QoL (Items 29 and 30) Scale Combined Score in Participants With PD-L1 CPS ≥1 at Week 6	-1.22 Score on a scale Interval -3.52 to 1.08	—

SECONDARY outcome

Timeframe: Baseline and Week 25

Population: All randomized participants who received at least one dose of study treatment and had at least one EORTC QLQ-C30 assessment data available for this outcome measure at Baseline and at Week 25.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=356 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=306 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-C30 GHS/QoL (Items 29 and 30) Scale Combined Score at Week 25	3.69 Score on a scale Interval 1.03 to 6.34	4.98 Score on a scale Interval 2.26 to 7.7

SECONDARY outcome

Timeframe: Baseline and Week 25

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=229 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=203 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-C30 GHS/QoL (Items 29 and 30) Scale Combined Score in Participants With PD-L1 CPS ≥10 at Week 25	2.13 Score on a scale Interval -1.15 to 5.4	5.16 Score on a scale Interval 1.86 to 8.45

SECONDARY outcome

Timeframe: Baseline and Week 25

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=340 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=291 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change in EORTC QLQ-C30 GHS/QoL (Items 29 and 30) Scale Combined Score in Participants With PD-L1 CPS ≥1 at Week 25	3.62 Score on a scale Interval 0.9 to 6.34	5.03 Score on a scale Interval 2.23 to 7.83

SECONDARY outcome

Timeframe: Baseline and Week 51

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=356 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=306 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-C30 GHS/QoL (Items 29 and 30) Scale Combined Score at Week 51	4.44 Score on a scale Interval 1.64 to 7.23	4.05 Score on a scale Interval 1.13 to 6.97

SECONDARY outcome

Timeframe: Baseline and Week 51

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=229 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=203 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-C30 GHS/QoL (Items 29 and 30) Scale Combined Score in Participants With PD-L1 CPS ≥10 at Week 51	4.00 Score on a scale Interval 0.67 to 7.33	4.39 Score on a scale Interval 0.9 to 7.87

SECONDARY outcome

Timeframe: Baseline and Week 51

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=340 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=291 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-C30 GHS/QoL (Items 29 and 30) Scale Combined Score in Participants With PD-L1 CPS ≥1 at Week 51	4.00 Score on a scale Interval 1.14 to 6.86	4.29 Score on a scale Interval 1.29 to 7.29

SECONDARY outcome

Timeframe: Baseline and Week 4

EORTC QLQ-C30 is a questionnaire to assess the overall QoL of cancer patients. Participant responses to 5 questions about their physical functioning (Items 1 to 5) are scored on a 4-point scale (1=Not at All to 4=Very Much). The combined score of items 1 to 5 was computed by averaging the raw scores of the 5 items and then applying a linear transformation to standardize the average score, so that the combined scores ranged from 0-100. A higher score indicated a better outcome. Per protocol, the change from baseline in EORTC QLQ-C30 physical functioning (Items 1-5) combined score for all randomized participants in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=352 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in Physical Functioning (EORTC QLQ-C30 Items 1-5) Combined Score at Week 4	-2.09 Score on a scale Interval -3.49 to -0.69	—

SECONDARY outcome

Timeframe: Baseline and Week 4

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=225 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in Physical Functioning (EORTC QLQ-C30 Items 1-5) Combined Score in Participants With PD-L1 CPS ≥10 at Week 4	-2.47 Score on a scale Interval -4.25 to -0.69	—

SECONDARY outcome

Timeframe: Baseline and Week 4

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=336 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in Physical Functioning (EORTC QLQ-C30 Items 1-5) Combined Score in Participants With PD-L1 CPS ≥1 at Week 4	-2.06 Score on a scale Interval -3.5 to -0.61	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-C30 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=354 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in Physical Functioning (EORTC QLQ-C30 Items 1-5) Combined Score at Week 6	-3.34 Score on a scale Interval -4.92 to -1.76	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants with PD-L1 CPS ≥10 who received at least one dose of study treatment and had at least one EORTC QLQ-C30 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=227 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in Physical Functioning (EORTC QLQ-C30 Items 1-5) Combined Score in Participants With PD-L1 CPS ≥10 at Week 6	-2.42 Score on a scale Interval -4.53 to -0.32	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants with PD-L1 CPS ≥1 who received at least one dose of study treatment and had at least one EORTC QLQ-C30 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=338 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in Physical Functioning (EORTC QLQ-C30 Items 1-5) Combined Score in Participants With PD-L1 CPS ≥1 at Week 6	-3.28 Score on a scale Interval -4.92 to -1.63	—

SECONDARY outcome

Timeframe: Baseline and Week 25

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=356 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=306 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in Physical Functioning (EORTC QLQ-C30 Items 1-5) Combined Score at Week 25	-7.48 Score on a scale Interval -9.72 to -5.25	-7.83 Score on a scale Interval -10.15 to -5.5

SECONDARY outcome

Timeframe: Baseline and Week 25

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=229 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=203 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in Physical Functioning (EORTC QLQ-C30 Items 1-5) Combined Score in Participants With PD-L1 CPS ≥10 at Week 25	-6.22 Score on a scale Interval -8.91 to -3.53	-6.75 Score on a scale Interval -9.47 to -4.03

SECONDARY outcome

Timeframe: Baseline and Week 25

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=340 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=291 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in Physical Functioning (EORTC QLQ-C30 Items 1-5) Combined Score in Participants With PD-L1 CPS ≥1 at Week 25	-7.42 Score on a scale Interval -9.71 to -5.13	-8.07 Score on a scale Interval -10.46 to -5.68

SECONDARY outcome

Timeframe: Baseline and Week 51

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=356 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=306 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in Physical Functioning (EORTC QLQ-C30 Items 1-5) Combined Score at Week 51	-6.57 Score on a scale Interval -8.91 to -4.22	-5.12 Score on a scale Interval -7.57 to -2.66

SECONDARY outcome

Timeframe: Baseline and Week 51

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=229 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=203 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in Physical Functioning (EORTC QLQ-C30 Items 1-5) Combined Score in Participants With PD-L1 CPS ≥10 at Week 51	-7.15 Score on a scale Interval -10.03 to -4.27	-4.70 Score on a scale Interval -7.74 to -1.66

SECONDARY outcome

Timeframe: Baseline and Week 51

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=340 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=291 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in Physical Functioning (EORTC QLQ-C30 Items 1-5) Combined Score in Participants With PD-L1 CPS ≥1 at Week 51	-6.87 Score on a scale Interval -9.32 to -4.43	-5.11 Score on a scale Interval -7.69 to -2.54

SECONDARY outcome

Timeframe: Baseline and Week 4

Population: All randomized participants in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 4. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the swallowing scale (Items 35-38) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 swallowing symptoms (Items 35-38) combined score for all randomized participants in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=352 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-Head and Neck Module 35 [H&N35] (Items 35-38) Swallowing Combined Score at Week 4	-3.36 Score on a scale Interval -5.9 to -0.83	—

SECONDARY outcome

Timeframe: Baseline and Week 4

Population: All randomized participants with PD-L1 CPS ≥10 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 4. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=225 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 35-38) Swallowing Combined Score in Participants With PD-L1 CPS ≥10 at Week 4	-6.64 Score on a scale Interval -9.73 to -3.55	—

SECONDARY outcome

Timeframe: Baseline and Week 4

Population: All randomized participants with PD-L1 CPS ≥1 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 4. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=336 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 35-38) Swallowing Combined Score in Participants With PD-L1 CPS ≥1 at Week 4	-3.98 Score on a scale Interval -6.56 to -1.4	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=354 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 35-38) Swallowing Combined Score at Week 6	-2.39 Score on a scale Interval -4.78 to -0.01	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants with PD-L1 CPS ≥10 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=227 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 35-38) Swallowing Combined Score in Participants With PD-L1 CPS ≥10 at Week 6	-5.06 Score on a scale Interval -7.86 to -2.27	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants with PD-L1 CPS ≥1 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=338 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 35-38) Swallowing Combined Score in Participants With PD-L1 CPS ≥1 at Week 6	-3.05 Score on a scale Interval -5.47 to -0.63	—

SECONDARY outcome

Timeframe: Baseline and Week 25

Population: All randomized participants who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 25.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=356 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=306 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 35-38) Swallowing Combined Score at Week 25	4.04 Score on a scale Interval 0.5 to 7.58	7.32 Score on a scale Interval 3.69 to 10.95

SECONDARY outcome

Timeframe: Baseline and Week 25

Population: All randomized participants with PD-L1 CPS ≥10 who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 25.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=229 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=203 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 35-38) Swallowing Combined Score in Participants With PD-L1 CPS ≥10 at Week 25	3.89 Score on a scale Interval -0.47 to 8.24	5.06 Score on a scale Interval 0.67 to 9.46

SECONDARY outcome

Timeframe: Baseline and Week 25

Population: All randomized participants with PD-L1 CPS ≥1 who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 25.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=340 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=291 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 35-38) Swallowing Combined Score in Participants With PD-L1 CPS ≥1 at Week 25	4.20 Score on a scale Interval 0.59 to 7.82	6.72 Score on a scale Interval 3.0 to 10.45

SECONDARY outcome

Timeframe: Baseline and Week 51

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=356 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=306 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 35-38) Swallowing Combined Score at Week 51	1.57 Score on a scale Interval -2.07 to 5.21	2.05 Score on a scale Interval -1.77 to 5.88

SECONDARY outcome

Timeframe: Baseline and Week 51

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=229 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=203 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 35-38) Swallowing Combined Score in Participants With PD-L1 CPS ≥10 at Week 51	0.50 Score on a scale Interval -3.9 to 4.9	0.93 Score on a scale Interval -3.74 to 5.59

SECONDARY outcome

Timeframe: Baseline and Week 51

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=340 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=291 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 35-38) Swallowing Combined Score in Participants With PD-L1 CPS ≥1 at Week 51	1.25 Score on a scale Interval -2.46 to 4.95	1.47 Score on a scale Interval -2.45 to 5.38

SECONDARY outcome

Timeframe: Baseline and Week 4

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the speech scale (Items 46, 53-54) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 speech symptoms (Items 46, 53-54) combined score for all randomized participants in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=352 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 46, 53-54) Speech Combined Score at Week 4	-2.31 Score on a scale Interval -4.74 to 0.12	—

SECONDARY outcome

Timeframe: Baseline and Week 4

Population: All randomized participants with PD-L1 CPS ≥10 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 4. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the speech scale (Items 46, 53-54) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 speech symptoms (Items 46, 53-54) combined score for all randomized participants with PD-L1 CPS ≥10 in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=225 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 46, 53-54) Speech Combined Score in Participants With PD-L1 CPS ≥10 at Week 4	-4.06 Score on a scale Interval -7.28 to -0.84	—

SECONDARY outcome

Timeframe: Baseline and Week 4

Population: All randomized participants with PD-L1 CPS ≥1 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 4. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the speech scale (Items 46, 53-54) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 speech symptoms (Items 46, 53-54) combined score for all randomized participants with PD-L1 CPS ≥1 in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=336 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 46, 53-54) Speech Combined Score in Participants With PD-L1 CPS ≥1 at Week 4	-2.17 Score on a scale Interval -4.61 to 0.27	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the speech scale (Items 46, 53-54) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 speech symptoms (Items 46, 53-54) combined score for all randomized participants in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=354 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 46, 53-54) Speech Combined Score at Week 6	-0.74 Score on a scale Interval -3.14 to 1.67	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants with PD-L1 CPS ≥10 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the speech scale (Items 46, 53-54) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 speech symptoms (Items 46, 53-54) combined score for all randomized participants with PD-L1 CPS ≥10 in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=227 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 46, 53-54) Speech Combined Score in Participants With PD-L1 CPS ≥10 at Week 6	-2.84 Score on a scale Interval -5.96 to 0.27	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants with PD-L1 CPS ≥1 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the speech scale (Items 46, 53-54) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 speech symptoms (Items 46, 53-54) combined score for all randomized participants with PD-L1 CPS ≥1 in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=338 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 46, 53-54) Speech Combined Score in Participants With PD-L1 CPS ≥1 at Week 6	-0.76 Score on a scale Interval -3.22 to 1.7	—

SECONDARY outcome

Timeframe: Baseline and Week 25

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the speech scale (Items 46, 53-54) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 speech symptoms (Items 46, 53-54) combined score for all randomized participants was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=356 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=306 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 46, 53-54) Speech Combined Score at Week 25	9.80 Score on a scale Interval 6.47 to 13.13	8.50 Score on a scale Interval 5.04 to 11.96

SECONDARY outcome

Timeframe: Baseline and Week 25

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the speech scale (Items 46, 53-54) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 speech symptoms (Items 46, 53-54) combined score for all randomized participants with PD-L1 CPS ≥10 was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=229 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=203 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 46, 53-54) Speech Combined Score in Participants With PD-L1 CPS ≥10 at Week 25	8.44 Score on a scale Interval 4.47 to 12.41	7.46 Score on a scale Interval 3.36 to 11.57

SECONDARY outcome

Timeframe: Baseline and Week 25

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the speech scale (Items 46, 53-54) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 speech symptoms (Items 46, 53-54) combined score for all randomized participants with PD-L1 CPS ≥1 was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=340 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=291 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 46, 53-54) Speech Combined Score in Participants With PD-L1 CPS ≥1 at Week 25	10.01 Score on a scale Interval 6.64 to 13.39	9.27 Score on a scale Interval 5.74 to 12.8

SECONDARY outcome

Timeframe: Baseline and Week 51

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the speech scale (Items 46, 53-54) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 speech symptoms (Items 46, 53-54) combined score for all randomized participants was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=356 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=306 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 46, 53-54) Speech Combined Score at Week 51	5.54 Score on a scale Interval 1.81 to 9.27	5.78 Score on a scale Interval 1.91 to 9.65

SECONDARY outcome

Timeframe: Baseline and Week 51

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the speech scale (Items 46, 53-54) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 speech symptoms (Items 46, 53-54) combined score for all randomized participants with PD-L1 CPS ≥10 was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=229 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=203 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 46, 53-54) Speech Combined Score in Participants With PD-L1 CPS ≥10 at Week 51	6.34 Score on a scale Interval 1.65 to 11.03	4.11 Score on a scale Interval -0.81 to 9.04

SECONDARY outcome

Timeframe: Baseline and Week 51

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the speech scale (Items 46, 53-54) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 speech symptoms (Items 46, 53-54) combined score for all randomized participants with PD-L1 CPS ≥1 was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=340 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=291 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 46, 53-54) Speech Combined Score in Participants With PD-L1 CPS ≥1 at Week 51	6.10 Score on a scale Interval 2.27 to 9.92	5.10 Score on a scale Interval 1.1 to 9.11

SECONDARY outcome

Timeframe: Baseline and Week 4

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the pain scale (Items 31-34) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 pain symptoms (Items 31-34) combined score for all randomized participants in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=352 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 31-34) Pain Combined Score at Week 4	-2.80 Score on a scale Interval -5.14 to -0.46	—

SECONDARY outcome

Timeframe: Baseline and Week 4

Population: All randomized participants with PD-L1 CPS ≥10 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 4. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the pain scale (Items 31-34) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 pain symptoms (Items 31-34) combined score for all randomized participants with PD-L1 CPS ≥10 in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=225 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 31-34) Pain Combined Score in Participants With PD-L1 CPS ≥10 at Week 4	-5.54 Score on a scale Interval -8.5 to -2.59	—

SECONDARY outcome

Timeframe: Baseline and Week 4

Population: All randomized participants with PD-L1 CPS ≥1 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 4. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the pain scale (Items 31-34) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 pain symptoms (Items 31-34) combined score for all randomized participants with PD-L1 CPS ≥1 in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=336 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 31-34) Pain Combined Score in Participants With PD-L1 CPS ≥1 at Week 4	-3.25 Score on a scale Interval -5.67 to -0.84	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the pain scale (Items 31-34) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 pain symptoms (Items 31-34) combined score for all randomized participants in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=354 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 31-34) Pain Combined Score at Week 6	-6.27 Score on a scale Interval -8.68 to -3.87	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants with PD-L1 CPS ≥10 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the pain scale (Items 31-34) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 pain symptoms (Items 31-34) combined score for all randomized participants with PD-L1 CPS ≥10 in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=227 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 31-34) Pain Combined Score in Participants With PD-L1 CPS ≥10 at Week 6	-9.14 Score on a scale Interval -12.17 to -6.11	—

SECONDARY outcome

Timeframe: Baseline and Week 6

Population: All randomized participants with PD-L1 CPS ≥1 in the pembrolizumab + SOC treatment group who received at least one dose of study treatment and had at least one EORTC QLQ-H\&N35 assessment data available for this outcome measure at Baseline and at Week 6. Per protocol, this outcome measure was only reported in participants in the pembrolizumab + SOC arm.

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the pain scale (Items 31-34) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 pain symptoms (Items 31-34) combined score for all randomized participants with PD-L1 CPS ≥1 in the pembrolizumab + SOC arm was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=338 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Neoadjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 31-34) Pain Combined Score in Participants With PD-L1 CPS ≥1 at Week 6	-6.76 Score on a scale Interval -9.23 to -4.28	—

SECONDARY outcome

Timeframe: Baseline and Week 25

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the pain scale (Items 31-34) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 pain symptoms (Items 31-34) combined score for all randomized participants was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=356 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=306 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 31-34) Pain Combined Score at Week 25	-12.16 Score on a scale Interval -15.2 to -9.12	-9.41 Score on a scale Interval -12.52 to -6.29

SECONDARY outcome

Timeframe: Baseline and Week 25

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the pain scale (Items 31-34) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 pain symptoms (Items 31-34) combined score for all randomized participants with PD-L1 CPS ≥10 was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=229 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=203 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 31-34) Pain Combined Score in Participants With PD-L1 CPS ≥10 at Week 25	-11.18 Score on a scale Interval -14.8 to -7.55	-11.43 Score on a scale Interval -15.11 to -7.76

SECONDARY outcome

Timeframe: Baseline and Week 25

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the pain scale (Items 31-34) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 pain symptoms (Items 31-34) combined score for all randomized participants with PD-L1 CPS ≥1 was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=340 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=291 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 31-34) Pain Combined Score in Participants With PD-L1 CPS ≥1 at Week 25	-11.79 Score on a scale Interval -14.91 to -8.67	-9.57 Score on a scale Interval -12.8 to -6.35

SECONDARY outcome

Timeframe: Baseline and Week 51

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the pain scale (Items 31-34) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 pain symptoms (Items 31-34) combined score for all randomized participants was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=356 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=306 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 31-34) Pain Combined Score at Week 51	-14.82 Score on a scale Interval -17.87 to -11.77	-12.05 Score on a scale Interval -15.21 to -8.89

SECONDARY outcome

Timeframe: Baseline and Week 51

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the pain scale (Items 31-34) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 pain symptoms (Items 31-34) combined score for all randomized participants with PD-L1 CPS ≥10 was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=229 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=203 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 31-34) Pain Combined Score in Participants With PD-L1 CPS ≥10 at Week 51	-16.34 Score on a scale Interval -20.12 to -12.56	-13.53 Score on a scale Interval -17.47 to -9.6

SECONDARY outcome

Timeframe: Baseline and Week 51

EORTC QLQ-H\&N35 is a 35-item questionnaire to assess QoL of head and neck cancer participants and consists of 7 multi-item scales (pain in the mouth, problems with swallowing, senses, speech, social eating, social contact, and sexuality). Participant responses to the pain scale (Items 31-34) were scored on a 4-point scale (1=Not at all to 4=Very much). Raw scores were standardized by linear transformation so that scores ranged from 0 to 100; a higher score indicated more problems. Per protocol, the change from baseline in EORTC QLQ-H\&N35 pain symptoms (Items 31-34) combined score for all randomized participants with PD-L1 CPS ≥1 was presented.

Outcome measures

Outcome measures
Measure	Pembrolizumab + Standard of Care (SOC) n=340 Participants Neoadjuvant treatment: Participants received 200 mg pembrolizumab by intravenous (IV) infusion administered on Day 1 of a 21-day cycle for 2 cycles (up to 6 weeks) prior to surgery. Adjuvant treatment: Following surgical resection, participants received 200 mg pembrolizumab, IV infusion, on Day 1 of a 21-day cycle for 15 cycles (up to 45 weeks) plus investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).	Standard of Care (SOC) n=291 Participants Adjuvant treatment: Following surgical resection, participants received investigator's choice of SOC treatment regimen consisting of radiotherapy, with or without cisplatin 100 mg/m\^2, IV infusion, on Day 1 of a 21-day cycle for 3 cycles (up to 9 weeks).
Adjuvant Treatment: Change From Baseline in EORTC QLQ-H&N35 (Items 31-34) Pain Combined Score in Participants With PD-L1 CPS ≥1 at Week 51	-15.03 Score on a scale Interval -18.17 to -11.88	-11.99 Score on a scale Interval -15.26 to -8.72

SECONDARY outcome

Timeframe: Up to ~92 months

OS was defined as the time from randomization to death due to any cause. OS for all randomized participants was presented.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to ~92 months

OS was defined as the time from randomization to death due to any cause. OS for all randomized participants with PD-L1 CPS ≥10 was presented.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to ~92 months

OS was defined as the time from randomization to death due to any cause. OS for all randomized participants with PD-L1 CPS ≥1 was presented.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to ~92 months

An AE was any untoward medical occurrence in a clinical study participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. An AE could have been any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated). The number of participants who experienced one or more AEs was reported.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to ~92 months

Outcome measures

Outcome data not reported

Adverse Events

Pembrolizumab + Standard of Care (SOC)

Serious events: 179 serious events

Other events: 335 other events

Deaths: 113 deaths

Standard of Care (SOC)

Serious events: 116 serious events

Other events: 290 other events

Deaths: 131 deaths

Serious adverse events

Other adverse events

Additional Information

Senior Vice President, Global Clinical Development

Merck Sharp & Dohme LLC

Phone: 1-800-672-6372

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee The Sponsor will generally support publication of multicenter studies only in their entirety and not as individual site data. In this case, a coordinating investigator will be designated by mutual agreement. If publication activity is not directed by the Sponsor, the investigator agrees to submit all manuscripts or abstracts to the Sponsor before submission. This allows the Sponsor to protect proprietary information and to provide comments.
Publication restrictions are in place

Restriction type: OTHER