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← Gastroesophageal Junction Carcinoma

NCT03221426 · STUDY IN CONTEXT

Study of Pembrolizumab (MK-3475) Plus Chemotherapy Versus Placebo Plus Chemotherapy in Participants With Gastric or Gastroesophageal Junction (GEJ) Adenocarcinoma (MK-3475-585/KEYN

Draft scope assessment: narrower. Linked by condition-string match at the cancer-entity level. The study's eligibility - stage, biomarker, treatment line and prior therapy - has not been reconciled against this page's definition, so its population is narrower than this page in ways not yet recorded. The condition was transformed or resolved through the terminology hierarchy to reach this cancer type, so the link itself is a candidate a reviewer must confirm. Found because this study's registry identifier is printed in an FDA approval notice, an FDA product label or an NCI summary held by this site. The citing document and the exact position of the identifier inside it are recorded. Being cited is not a statement that the study supports this treatment.

Read the full study record and all posted results →

Linked outcomes

Measures are not ranked. Open each original source section for treatment groups, denominators, units and results.

primary · POSTED

EFS was based on RECIST 1.1 as assessed by the investigator and was defined as the time from randomization to the first of the following events: radiographic disease progression per RECIST 1.1; local or distant recurrence as assessed by computer tomography (CT) scan or biopsy if indicated (for participants who were disease free after surgery); clinical progression as evidenced by peritoneal carcinomatosis confirmed by preoperative laparoscopy or laparotomy (for participants who were confirmed to be free of peritoneal involvement by laparoscopy at screening); or death due to any cause. A second primary malignancy, or radiographic progressive disease (PD) during the neoadjuvant phase that does not preclude successful surgery (i.e., disease free after surgery), were not considered EFS events.

The analysis population consisted of all randomized participants in the Pembrolizumab+XP/FP and Placebo+XP/FP treatment arms, as pre-specified per protocol.

→

primary · POSTED

PathCR rate was defined as the percentage of participants having a pathCR based on central review. pathCR was defined as no invasive disease within an entirely submitted and evaluated gross lesion, and histologically negative nodes. The percentage of participants having pathCR was presented for the Pembrolizumab+XP/FP and Placebo+XP/FP treatment arms.

The analysis population consisted of all randomized participants in the Pembrolizumab+XP/FP and Placebo+XP/FP treatment arms, as pre-specified per protocol.

→

primary · POSTED

OS was defined as the time from randomization to death due to any cause. OS was presented for the Pembrolizumab+XP/FP and Placebo+XP/FP treatment arms.

The analysis population consisted of all randomized participants in the Pembrolizumab+XP/FP and Placebo+XP/FP treatment arms, as pre-specified per protocol.

→

primary · POSTED

An AE was defined as any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants who experience at least one AE was presented for the Pembrolizumab+FLOT and Placebo+FLOT Cohorts.

The analysis population consisted of all participants who received ≥1 dose of study treatment in the Pembrolizumab+FLOT and Placebo+FLOT Cohort treatment arms, as pre-specified per protocol.

→

primary · POSTED

An AE was defined as any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants who discontinued study treatment due to an AE was presented for the Pembrolizumab+FLOT and Placebo+FLOT Cohorts.

The analysis population consisted of all participants who received ≥1 dose of study treatment in the Pembrolizumab+FLOT and Placebo+FLOT Cohort treatment arms, as pre-specified per protocol.

→

secondary · POSTED

An AE was defined as any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants who experienced at least one AE was presented for the Pembrolizumab+XP/FP and Placebo+XP/FP treatment arms separately and in combination with the Pembrolizumab+FLOT and Placebo+FLOT Cohorts.

The analysis population consisted of all participants who received ≥1 dose of study treatment for the Pembrolizumab+XP/FP and Placebo+XP/FP treatment arms separately and in combination with the Pembrolizumab+FLOT and Placebo+FLOT Cohorts, as pre-specified per protocol.

→

Reported safety

Serious events are not the same as severe events. Compare the original safety groups and their at-risk populations.

Open the study safety table →

Quality of life and patient-reported measures

No linked quality-of-life measure is recorded for this setting and study.

Full draft applicability and source-link record
trial
release id
clinical-indications-draft-1
disease state id
ds-gastroesophageal-junction-carcinoma
nct id
NCT03221426
trial label
Study of Pembrolizumab (MK-3475) Plus Chemotherapy Versus Placebo Plus Chemotherapy in Participants With Gastric or Gastroesophageal Junction (GEJ) Adenocarcinoma (MK-3475-585/KEYN
applicability
narrower
applicability note
Linked by condition-string match at the cancer-entity level. The study's eligibility - stage, biomarker, treatment line and prior therapy - has not been reconciled against this page's definition, so its population is narrower than this page in ways not yet recorded. The condition was transformed or resolved through the terminology hierarchy to reach this cancer type, so the link itself is a candidate a reviewer must confirm.
curation status
draft
reviewed by
Source null
reviewed at
Source null
created at
2026-09-10T00:00:00Z
provenance class
regulator-cited
discovery note
Found because this study's registry identifier is printed in an FDA approval notice, an FDA product label or an NCI summary held by this site. The citing document and the exact position of the identifier inside it are recorded. Being cited is not a statement that the study supports this treatment.
outcome Count
6
harms Count
6
qol Count
0
outcomes
  1. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0000
    source section id
    NCT03221426-om-0000
    source outcome index
    0
    endpoint
    Event-free Survival (EFS) Per Response Criteria in Solid Tumors Version 1.1 (RECIST 1.1) - Pembrolizumab+XP/FP and Placebo+XP/FP Treatment Arms
    endpoint definition
    EFS was based on RECIST 1.1 as assessed by the investigator and was defined as the time from randomization to the first of the following events: radiographic disease progression per RECIST 1.1; local or distant recurrence as assessed by computer tomography (CT) scan or biopsy if indicated (for participants who were disease free after surgery); clinical progression as evidenced by peritoneal carcinomatosis confirmed by preoperative laparoscopy or laparotomy (for participants who were confirmed to be free of peritoneal involvement by laparoscopy at screening); or death due to any cause. A second primary malignancy, or radiographic progressive disease (PD) during the neoadjuvant phase that does not preclude successful surgery (i.e., disease free after surgery), were not considered EFS events.
    time origin
    Up to approximately 75 months
    analysis role
    primary
    reporting status
    POSTED
    data cutoff
    Source null
    population note
    The analysis population consisted of all randomized participants in the Pembrolizumab+XP/FP and Placebo+XP/FP treatment arms, as pre-specified per protocol.
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  2. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0001
    source section id
    NCT03221426-om-0001
    source outcome index
    1
    endpoint
    Pathological Complete Response (pathCR) Rate - Pembrolizumab+XP/FP and Placebo+XP/FP Treatment Arms
    endpoint definition
    PathCR rate was defined as the percentage of participants having a pathCR based on central review. pathCR was defined as no invasive disease within an entirely submitted and evaluated gross lesion, and histologically negative nodes. The percentage of participants having pathCR was presented for the Pembrolizumab+XP/FP and Placebo+XP/FP treatment arms.
    time origin
    Up to approximately 9 weeks following completion of neoadjuvant treatment (up to Study Week 18)
    analysis role
    primary
    reporting status
    POSTED
    data cutoff
    Source null
    population note
    The analysis population consisted of all randomized participants in the Pembrolizumab+XP/FP and Placebo+XP/FP treatment arms, as pre-specified per protocol.
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  3. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0002
    source section id
    NCT03221426-om-0002
    source outcome index
    2
    endpoint
    Overall Survival (OS) - Pembrolizumab+XP/FP and Placebo+XP/FP Treatment Arms
    endpoint definition
    OS was defined as the time from randomization to death due to any cause. OS was presented for the Pembrolizumab+XP/FP and Placebo+XP/FP treatment arms.
    time origin
    Up to approximately 75 months
    analysis role
    primary
    reporting status
    POSTED
    data cutoff
    Source null
    population note
    The analysis population consisted of all randomized participants in the Pembrolizumab+XP/FP and Placebo+XP/FP treatment arms, as pre-specified per protocol.
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  4. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0003
    source section id
    NCT03221426-om-0003
    source outcome index
    3
    endpoint
    Number of Participants Who Experienced One or More Adverse Events (AEs) - Pembrolizumab+FLOT and Placebo+FLOT Cohorts
    endpoint definition
    An AE was defined as any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants who experience at least one AE was presented for the Pembrolizumab+FLOT and Placebo+FLOT Cohorts.
    time origin
    Up to approximately 70 months
    analysis role
    primary
    reporting status
    POSTED
    data cutoff
    Source null
    population note
    The analysis population consisted of all participants who received ≥1 dose of study treatment in the Pembrolizumab+FLOT and Placebo+FLOT Cohort treatment arms, as pre-specified per protocol.
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  5. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0004
    source section id
    NCT03221426-om-0004
    source outcome index
    4
    endpoint
    Number of Participants Who Discontinued Study Treatment Due to an AE - Pembrolizumab+FLOT and Placebo+FLOT Cohorts
    endpoint definition
    An AE was defined as any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants who discontinued study treatment due to an AE was presented for the Pembrolizumab+FLOT and Placebo+FLOT Cohorts.
    time origin
    Up to approximately 17 months
    analysis role
    primary
    reporting status
    POSTED
    data cutoff
    Source null
    population note
    The analysis population consisted of all participants who received ≥1 dose of study treatment in the Pembrolizumab+FLOT and Placebo+FLOT Cohort treatment arms, as pre-specified per protocol.
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  6. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0005
    source section id
    NCT03221426-om-0005
    source outcome index
    5
    endpoint
    Number of Participants Who Experienced One or More Adverse Events (AEs) - Pembrolizumab+XP/FP and Placebo+XP/FP Treatment Arms Separately and in Combination With the Pembrolizumab+FLOT and Placebo+FLOT Cohorts
    endpoint definition
    An AE was defined as any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants who experienced at least one AE was presented for the Pembrolizumab+XP/FP and Placebo+XP/FP treatment arms separately and in combination with the Pembrolizumab+FLOT and Placebo+FLOT Cohorts.
    time origin
    Up to approximately 89 months
    analysis role
    secondary
    reporting status
    POSTED
    data cutoff
    Source null
    population note
    The analysis population consisted of all participants who received ≥1 dose of study treatment for the Pembrolizumab+XP/FP and Placebo+XP/FP treatment arms separately and in combination with the Pembrolizumab+FLOT and Placebo+FLOT Cohorts, as pre-specified per protocol.
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
arms
  1. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0000
    arm key
    OG000
    arm label
    Pembrolizumab + XP/FP
    regimen
    XP=cisplatin+capecitabine and FP=cisplatin+5-fluorouracil. Neoadjuvant: Prior to surgery, participants received 3 cycles of pembrolizumab 200 mg via intravenous (IV) infusion on Day 1 of each 3-week cycle (Q3W) PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets twice each day (BID) on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5-fluorouracil (5FU) 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle. Adjuvant: 4 to 10 weeks post-surgery, participants received 3 cycles of pembrolizumab 200 mg via IV infusion on Day 1 Q3W PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets BID on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5FU 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle, followed by pembrolizumab monotherapy 200 mg via IV infusion on Day 1 Q3W for up to 11 additional cycles.
    analyzed count
    402
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT03221426-om-0000#groups/OG000
  2. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0000
    arm key
    OG001
    arm label
    Placebo + XP/FP
    regimen
    Neoadjuvant: Prior to surgery, participants received 3 cycles of placebo (normal saline solution) via IV infusion on Day 1 Q3W PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets BID on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5FU 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle. Adjuvant: 4 to 10 weeks post-surgery, participants received 3 cycles of placebo via IV infusion on Day 1 Q3W PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets BID on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5FU 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle, followed by placebo monotherapy via IV infusion on Day 1 Q3W for up to 11 additional cycles.
    analyzed count
    402
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT03221426-om-0000#groups/OG001
  3. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0001
    arm key
    OG000
    arm label
    Pembrolizumab + XP/FP
    regimen
    XP=cisplatin+capecitabine and FP=cisplatin+5-fluorouracil. Neoadjuvant: Prior to surgery, participants received 3 cycles of pembrolizumab 200 mg via intravenous (IV) infusion on Day 1 of each 3-week cycle (Q3W) PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets twice each day (BID) on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5-fluorouracil (5FU) 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle. Adjuvant: 4 to 10 weeks post-surgery, participants received 3 cycles of pembrolizumab 200 mg via IV infusion on Day 1 Q3W PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets BID on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5FU 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle, followed by pembrolizumab monotherapy 200 mg via IV infusion on Day 1 Q3W for up to 11 additional cycles.
    analyzed count
    402
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT03221426-om-0001#groups/OG000
  4. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0001
    arm key
    OG001
    arm label
    Placebo + XP/FP
    regimen
    Neoadjuvant: Prior to surgery, participants received 3 cycles of placebo (normal saline solution) via IV infusion on Day 1 Q3W PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets BID on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5FU 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle. Adjuvant: 4 to 10 weeks post-surgery, participants received 3 cycles of placebo via IV infusion on Day 1 Q3W PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets BID on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5FU 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle, followed by placebo monotherapy via IV infusion on Day 1 Q3W for up to 11 additional cycles.
    analyzed count
    402
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT03221426-om-0001#groups/OG001
  5. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0002
    arm key
    OG000
    arm label
    Pembrolizumab + XP/FP
    regimen
    XP=cisplatin+capecitabine and FP=cisplatin+5-fluorouracil. Neoadjuvant: Prior to surgery, participants received 3 cycles of pembrolizumab 200 mg via intravenous (IV) infusion on Day 1 of each 3-week cycle (Q3W) PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets twice each day (BID) on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5-fluorouracil (5FU) 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle. Adjuvant: 4 to 10 weeks post-surgery, participants received 3 cycles of pembrolizumab 200 mg via IV infusion on Day 1 Q3W PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets BID on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5FU 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle, followed by pembrolizumab monotherapy 200 mg via IV infusion on Day 1 Q3W for up to 11 additional cycles.
    analyzed count
    402
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT03221426-om-0002#groups/OG000
  6. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0002
    arm key
    OG001
    arm label
    Placebo + XP/FP
    regimen
    Neoadjuvant: Prior to surgery, participants received 3 cycles of placebo (normal saline solution) via IV infusion on Day 1 Q3W PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets BID on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5FU 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle. Adjuvant: 4 to 10 weeks post-surgery, participants received 3 cycles of placebo via IV infusion on Day 1 Q3W PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets BID on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5FU 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle, followed by placebo monotherapy via IV infusion on Day 1 Q3W for up to 11 additional cycles.
    analyzed count
    402
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT03221426-om-0002#groups/OG001
  7. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0003
    arm key
    OG000
    arm label
    Pembrolizumab + FLOT Cohort
    regimen
    FLOT=docetaxel+oxaliplatin+5FU+leucovorin (calcium folinate). Neoadjuvant: Prior to surgery, participants received 3 cycles of pembrolizumab 200 mg via IV infusion on Day 1 Q3W PLUS docetaxel 50 mg/m\^2 via IV infusion, oxaliplatin 85 mg/m\^2 via IV infusion, 5FU 2600 mg/m\^2 via IV infusion, and leucovorin (calcium folinate) 200 mg/m\^2 via IV infusion Q2W (on Days 1 and 15 of Cycle 1; Day 8 of Cycle 2, and Day 1 of Cycle 3, for 4 administrations). Adjuvant: 4 to 10 weeks post-surgery, participants received 3 cycles of pembrolizumab 200 mg via IV infusion Day 1 Q3W PLUS docetaxel 50 mg/m\^2, oxaliplatin 85 mg/m\^2, 5FU 2600 mg/m\^2, and leucovorin 200 mg/m\^2 Q2W (on Days 1 and 15 of Cycle 1; Day 8 of Cycle 2, and Day 1 of Cycle 3, for 4 administrations), followed by pembrolizumab monotherapy 200 mg via IV infusion on Day 1 Q3W for up to 11 additional cycles.
    analyzed count
    99
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT03221426-om-0003#groups/OG000
  8. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0003
    arm key
    OG001
    arm label
    Placebo + FLOT Cohort
    regimen
    Neoadjuvant: Prior to surgery, participants received 3 cycles of placebo (normal saline solution) via IV infusion on Day 1 Q3W PLUS docetaxel 50 mg/m\^2 via IV infusion, oxaliplatin 85 mg/m\^2 via IV infusion, 5FU 2600 mg/m\^2 via IV infusion, and leucovorin 200 mg/m\^2 via IV infusion Q2W (on Days 1 and 15 of Cycle 1; Day 8 of Cycle 2, and Day 1 of Cycle 3, for 4 administrations). Adjuvant: 4 to 10 weeks post-surgery, participants received 3 cycles of placebo via IV infusion on Day 1 Q3W PLUS docetaxel 50 mg/m\^2 via IV infusion, oxaliplatin 85 mg/m\^2 via IV infusion, 5FU 2600 mg/m\^2 via IV infusion, and leucovorin 200 mg/m\^2 via IV infusion Q2W (on Days 1 and 15 of Cycle 1; Day 8 of Cycle 2, and Day 1 of Cycle 3, for 4 administrations), followed by placebo monotherapy via IV infusion on Day 1 Q3W for up to 11 additional cycles.
    analyzed count
    103
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT03221426-om-0003#groups/OG001
  9. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0004
    arm key
    OG000
    arm label
    Pembrolizumab + FLOT Cohort
    regimen
    FLOT=docetaxel+oxaliplatin+5FU+leucovorin (calcium folinate). Neoadjuvant: Prior to surgery, participants received 3 cycles of pembrolizumab 200 mg via IV infusion on Day 1 Q3W PLUS docetaxel 50 mg/m\^2 via IV infusion, oxaliplatin 85 mg/m\^2 via IV infusion, 5FU 2600 mg/m\^2 via IV infusion, and leucovorin (calcium folinate) 200 mg/m\^2 via IV infusion Q2W (on Days 1 and 15 of Cycle 1; Day 8 of Cycle 2, and Day 1 of Cycle 3, for 4 administrations). Adjuvant: 4 to 10 weeks post-surgery, participants received 3 cycles of pembrolizumab 200 mg via IV infusion Day 1 Q3W PLUS docetaxel 50 mg/m\^2, oxaliplatin 85 mg/m\^2, 5FU 2600 mg/m\^2, and leucovorin 200 mg/m\^2 Q2W (on Days 1 and 15 of Cycle 1; Day 8 of Cycle 2, and Day 1 of Cycle 3, for 4 administrations), followed by pembrolizumab monotherapy 200 mg via IV infusion on Day 1 Q3W for up to 11 additional cycles.
    analyzed count
    99
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT03221426-om-0004#groups/OG000
  10. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0004
    arm key
    OG001
    arm label
    Placebo + FLOT Cohort
    regimen
    Neoadjuvant: Prior to surgery, participants received 3 cycles of placebo (normal saline solution) via IV infusion on Day 1 Q3W PLUS docetaxel 50 mg/m\^2 via IV infusion, oxaliplatin 85 mg/m\^2 via IV infusion, 5FU 2600 mg/m\^2 via IV infusion, and leucovorin 200 mg/m\^2 via IV infusion Q2W (on Days 1 and 15 of Cycle 1; Day 8 of Cycle 2, and Day 1 of Cycle 3, for 4 administrations). Adjuvant: 4 to 10 weeks post-surgery, participants received 3 cycles of placebo via IV infusion on Day 1 Q3W PLUS docetaxel 50 mg/m\^2 via IV infusion, oxaliplatin 85 mg/m\^2 via IV infusion, 5FU 2600 mg/m\^2 via IV infusion, and leucovorin 200 mg/m\^2 via IV infusion Q2W (on Days 1 and 15 of Cycle 1; Day 8 of Cycle 2, and Day 1 of Cycle 3, for 4 administrations), followed by placebo monotherapy via IV infusion on Day 1 Q3W for up to 11 additional cycles.
    analyzed count
    103
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT03221426-om-0004#groups/OG001
  11. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0005
    arm key
    OG000
    arm label
    Pembrolizumab + XP/FP
    regimen
    XP=cisplatin+capecitabine and FP=cisplatin+5-fluorouracil. Neoadjuvant: Prior to surgery, participants received 3 cycles of pembrolizumab 200 mg via intravenous (IV) infusion on Day 1 of each 3-week cycle (Q3W) PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets twice each day (BID) on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5-fluorouracil (5FU) 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle. Adjuvant: 4 to 10 weeks post-surgery, participants received 3 cycles of pembrolizumab 200 mg via IV infusion on Day 1 Q3W PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets BID on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5FU 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle, followed by pembrolizumab monotherapy 200 mg via IV infusion on Day 1 Q3W for up to 11 additional cycles.
    analyzed count
    399
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT03221426-om-0005#groups/OG000
  12. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    outcome key
    om-0005
    arm key
    OG001
    arm label
    Placebo + XP/FP
    regimen
    Neoadjuvant: Prior to surgery, participants received 3 cycles of placebo (normal saline solution) via IV infusion on Day 1 Q3W PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets BID on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5FU 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle. Adjuvant: 4 to 10 weeks post-surgery, participants received 3 cycles of placebo via IV infusion on Day 1 Q3W PLUS cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and capecitabine 1000 mg/m\^2 via oral tablets BID on Days 1 to 14 of each 3-week cycle OR cisplatin 80 mg/m\^2 via IV infusion on Day 1 Q3W and 5FU 800 mg/m\^2 via continuous IV infusion on Days 1 to 5 of each 3-week cycle, followed by placebo monotherapy via IV infusion on Day 1 Q3W for up to 11 additional cycles.
    analyzed count
    400
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT03221426-om-0005#groups/OG001
harms
  1. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    harm key
    EG000
    source section id
    NCT03221426-ae
    event group key
    EG000
    event group label
    Pembrolizumab + XP/FP
    serious affected
    174
    serious at risk
    399
    other affected
    392
    other at risk
    399
    frequency threshold
    5
    collection period
    Up to approximately 89 months
    event definition
    All-Cause Mortality includes all randomized participants. Serious and Other adverse events (AEs) includes all randomized participants who received ≥1 dose of study treatment. MedDRA preferred terms "Neoplasm progression", "Malignant neoplasm progression" \& "Disease progression" not related to study treatment are excluded as AEs. Per protocol, AEs are presented for the XP/FP and FLOT treatment arms separately and in combination.
    undenominated note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  2. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    harm key
    EG001
    source section id
    NCT03221426-ae
    event group key
    EG001
    event group label
    Placebo + XP/FP
    serious affected
    160
    serious at risk
    400
    other affected
    392
    other at risk
    400
    frequency threshold
    5
    collection period
    Up to approximately 89 months
    event definition
    All-Cause Mortality includes all randomized participants. Serious and Other adverse events (AEs) includes all randomized participants who received ≥1 dose of study treatment. MedDRA preferred terms "Neoplasm progression", "Malignant neoplasm progression" \& "Disease progression" not related to study treatment are excluded as AEs. Per protocol, AEs are presented for the XP/FP and FLOT treatment arms separately and in combination.
    undenominated note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  3. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    harm key
    EG002
    source section id
    NCT03221426-ae
    event group key
    EG002
    event group label
    Pembrolizumab + FLOT Cohort
    serious affected
    66
    serious at risk
    99
    other affected
    99
    other at risk
    99
    frequency threshold
    5
    collection period
    Up to approximately 89 months
    event definition
    All-Cause Mortality includes all randomized participants. Serious and Other adverse events (AEs) includes all randomized participants who received ≥1 dose of study treatment. MedDRA preferred terms "Neoplasm progression", "Malignant neoplasm progression" \& "Disease progression" not related to study treatment are excluded as AEs. Per protocol, AEs are presented for the XP/FP and FLOT treatment arms separately and in combination.
    undenominated note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  4. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    harm key
    EG003
    source section id
    NCT03221426-ae
    event group key
    EG003
    event group label
    Placebo + FLOT Cohort
    serious affected
    51
    serious at risk
    103
    other affected
    103
    other at risk
    103
    frequency threshold
    5
    collection period
    Up to approximately 89 months
    event definition
    All-Cause Mortality includes all randomized participants. Serious and Other adverse events (AEs) includes all randomized participants who received ≥1 dose of study treatment. MedDRA preferred terms "Neoplasm progression", "Malignant neoplasm progression" \& "Disease progression" not related to study treatment are excluded as AEs. Per protocol, AEs are presented for the XP/FP and FLOT treatment arms separately and in combination.
    undenominated note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  5. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    harm key
    EG004
    source section id
    NCT03221426-ae
    event group key
    EG004
    event group label
    Pembrolizumab + XP/FP and Pembrolizumab + FLOT Combined
    serious affected
    240
    serious at risk
    498
    other affected
    491
    other at risk
    498
    frequency threshold
    5
    collection period
    Up to approximately 89 months
    event definition
    All-Cause Mortality includes all randomized participants. Serious and Other adverse events (AEs) includes all randomized participants who received ≥1 dose of study treatment. MedDRA preferred terms "Neoplasm progression", "Malignant neoplasm progression" \& "Disease progression" not related to study treatment are excluded as AEs. Per protocol, AEs are presented for the XP/FP and FLOT treatment arms separately and in combination.
    undenominated note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  6. release id
    clinical-indications-draft-1
    disease state id
    ds-gastroesophageal-junction-carcinoma
    nct id
    NCT03221426
    harm key
    EG005
    source section id
    NCT03221426-ae
    event group key
    EG005
    event group label
    Placebo + XP/FP and Placebo + FLOT Combined
    serious affected
    211
    serious at risk
    503
    other affected
    495
    other at risk
    503
    frequency threshold
    5
    collection period
    Up to approximately 89 months
    event definition
    All-Cause Mortality includes all randomized participants. Serious and Other adverse events (AEs) includes all randomized participants who received ≥1 dose of study treatment. MedDRA preferred terms "Neoplasm progression", "Malignant neoplasm progression" \& "Disease progression" not related to study treatment are excluded as AEs. Per protocol, AEs are presented for the XP/FP and FLOT treatment arms separately and in combination.
    undenominated note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
quality of life
    setting source links

      Preserved source evidence · Not medical advice