A Phase 3 interventional study of Pembrolizumab and Placebo in Gastric Neoplasms and Gastroesophageal Junction Adenocarcinoma, sponsored by Merck Sharp & Dohme LLC. Completed at 192 sites in 20 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-26.
Sponsored by Merck Sharp & Dohme LLC (part of Merck & Co., Inc) · Phase 3, Interventional, and Treatment
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Among 41 studies testing pembrolizumab in Stomach Neoplasms — 7 open to participants now, 13 under way, 1 of them phase 3. pembrolizumab · Stomach Neoplasms.
Among the 41 studies testing pembrolizumab in Stomach Neoplasms, this one is the 4th largest by enrollment, is one of 8 that started in 2018, is one of 10 in phase 3, and was the 20th registered.
3,401 studies on the registry are indexed under Stomach Neoplasms; 993 are open to participants now.
Browse Stomach Neoplasms studies →7 of the 41 studies testing pembrolizumab in Stomach Neoplasms are open now, in 3 countries. Recruiting first, the newest first:
Fudan University · Sites in China
Ages 18–75
Shanghai Minimally Invasive Surgery Center · Sites in China
Ages 18–75
Second Affiliated Hospital of Guangzhou Medical University · Sites in China
Ages 18–70
Yonsei University · Sites in Korea, Republic of
Ages 19+
Fudan University · Sites in China
Ages 18+
By country, each count listing its studies:
pembrolizumab: first FDA approval 2014 (KEYTRUDA), first EMA approval 2015. What it is approved for, and how studies give it, is on its page →
Of the 704 Stomach Neoplasms studies recruiting now, 376 (53%) set no upper age limit and 194 (28%) stop at 75 or younger; 28 take children under 18; 69 take healthy volunteers.
This study: 18 Years and older · all sexes · no healthy volunteers.
The full table on the hub →This tab as a report to print or save as PDF → With an account.
On this site’s reading of the record, pembrolizumab is the treatment under test here. Read study by study →
41 studies; the count open now beside each. This study's row is marked.
A study in two phases is counted once above. Listed by phase, each with its combined phases: Phase 1 8 · Phase 2 27 · Phase 3 10 · Phase 4 1
First in 2014; this study’s year is marked. 8 started in 2018.
By drug class, each counting the studies that test any of its medicines:
This study's enrollment of 738 is above the median of 66 across 2,500 interventional studies indexed under Stomach Neoplasms.
Median enrollment 41 across the 41 interventional studies. Of the 25 that completed or were terminated, 22 (88%) have results posted.
This tab as a report to print or save as PDF → With an account.
12 of 41 have an industry lead sponsor. The 10 most frequent:
This study is registered under Merck Sharp & Dohme LLC, one of the names counted as Merck & Co., Inc. Under that name alone:
Merck Sharp & Dohme LLC is the lead sponsor of 2,166 studies on the registry; 131 are open to participants now.
Of its 503 completed or terminated interventional studies of FDA-regulated products, 371 (74%) have results posted.
18 studies in Stomach Neoplasms by Merck & Co., Inc: 1 open now, 1 under way, none of them phase 3. Of 14 finished, 13 (93%) have results posted.
Among the 18 studies in Stomach Neoplasms by Merck & Co., Inc, this one is the 4th largest by enrollment, is one of 4 that started in 2018, is one of 8 in phase 3, and was the 10th registered.
Merck & Co., Inc’s Stomach Neoplasms studies by the year they started, since 2007.
3 of the studies testing pembrolizumab in Stomach Neoplasms that are under way reach primary completion within a year, 1 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT04997837Phase 3Fudan UniversityStudy of Adjuvant Chemotherapy With or Without PD-1 Inhibitors and Chemoradiotherapy in Resected pN3 Gastric (G) or GEJ Adenocarcinoma | 2027-07-21 |
| NCT05041153M.D. Anderson Cancer CenterPembrolizumab and Lenvatinib for the Treatment of Advanced, Unresectable, or Metastatic Gastroesophageal Adenocarcinoma | 2026-12-30 |
| NCT04069273Harry H YoonNovel SEQUEnced Immunotherapy With Anti-angiogenesis and Chemotherapy in Advanced gastroesophageaL Adenocarcinoma | 2027-08-11 |
Add all 3 to your calendar (.ics) → With an account.
Among the 41 studies testing pembrolizumab in Stomach Neoplasms, from their registry updates:
Among Merck & Co., Inc’s 18 in Stomach Neoplasms:
This tab as a report to print or save as PDF → With an account.
The study will compare the efficacy and safety of pembrolizumab plus trastuzumab in combination with standard of care (SOC) chemotherapy versus trastuzumab in combination with SOC chemotherapy in participants with HER2-positive gastric cancer. The primary hypotheses of the study are that pembrolizumab plus trastuzumab in combination with chemotherapy is superior to trastuzumab plus chemotherapy in terms of 1) progression free survival (PFS) per Response Evaluation Criteria in Solid Tumors 1.1 (RECIST 1.1) as assessed by blinded independent central review (BICR), and 2) overall survival (OS).
Pembrolizumab (200 mg) or placebo will be administered intravenously [IV] on day 1 of each 3-week cycle. Trastuzumab (8 mg/kg loading dose, 6 mg/kg maintenance dose) will be administered IV on day 1 of each 3-week cycle. SOC chemotherapy for the global cohort will either be FP (80 mg/m\^2 cisplatin administered IV on Day 1 of each 3-week cycle and 800 mg/m\^2 5-fluorouracil [5-FU] administered IV on Days 1-5 of each 3-week cycle) or CAPOX (1000 mg/m\^2 capecitabine administered orally twice daily [BID] on days 1-14 of each 3-week cycle and 130 mg/m\^2 oxaliplatin administered IV on Day 1 of each 3-week cycle). A Japan cohort will receive SOX chemotherapy consisting of S-1 (tegafur, 5-chloro-2,4-dihydroxypyridine [CDHP], and potassium oxonate [Oxo]) administered orally BID according to Body Surface Area (BSA) on Days 1-14 of each 3-week cycle and oxaliplatin (130 mg/m\^2) administered IV on Day 1 each 3-week cycle.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Inclusion criteria include, but are not limited to:
Exclusion Criteria:
Exclusion criteria include, but are not limited to:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
HER2 is a protein, made from the ERBB2 gene, that drives the growth of some cancers. A study may look for a level of the protein, extra copies of the gene, or a particular change in it.
In breast cancer, protein tests are read as HER2-positive, HER2-low or HER2-negative; other cancers use their own rules. Check which test result the study requires.
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
PD-1, PD-L1 and CTLA-4 are proteins that act as brakes on the immune system. Checkpoint inhibitors, such as pembrolizumab or nivolumab, block them so the immune system can attack a cancer.
PD-L1 can also be measured in a tumour sample. Some scores count stained tumour cells only (TPS); others also count certain immune cells (CPS). The study names the score and the minimum it uses.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HER2
HER2 is a protein, made from the ERBB2 gene, that drives the growth of some cancers. A study may look for a level of the protein, extra copies of the gene, or a particular change in it.
In breast cancer, protein tests are read as HER2-positive, HER2-low or HER2-negative; other cancers use their own rules. Check which test result the study requires.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Measurable disease
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
RECIST
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
PD-1, PD-L1 and checkpoint inhibitors
PD-1, PD-L1 and CTLA-4 are proteins that act as brakes on the immune system. Checkpoint inhibitors, such as pembrolizumab or nivolumab, block them so the immune system can attack a cancer.
PD-L1 can also be measured in a tumour sample. Some scores count stained tumour cells only (TPS); others also count certain immune cells (CPS). The study names the score and the minimum it uses.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants received 200 mg pembrolizumab IV every 3 weeks (Q3W) plus trastuzumab (8 mg/kg loading dose, 6 mg/kg maintenance thereafter) IV Q3W in combination with investigator's choice of FP or CAPOX chemotherapy.
Biological: Pembrolizumab · Drug: Cisplatin · Drug: 5-FU · Drug: Oxaliplatin · Drug: Capecitabine · Biological: Trastuzumab
Participants received matched placebo to pembrolizumab IV Q3W plus trastuzumab (8mg/kg loading dose, 6mg/kg maintenance thereafter) IV Q3W in combination with investigator's choice of FP or CAPOX chemotherapy.
Biological: Placebo · Drug: Cisplatin · Drug: 5-FU · Drug: Oxaliplatin · Drug: Capecitabine · Biological: Trastuzumab
Participants received 200 mg pembrolizumab IV every 3 weeks (Q3W) plus trastuzumab (8 mg/kg loading dose, 6 mg/kg maintenance thereafter) IV Q3W in combination with SOX chemotherapy.
Biological: Pembrolizumab · Drug: Oxaliplatin · Drug: S-1 · Biological: Trastuzumab
Participants received matched placebo to pembrolizumab IV Q3W plus trastuzumab (8mg/kg loading dose, 6mg/kg maintenance thereafter) IV Q3W in combination with SOX chemotherapy.
Biological: Placebo · Drug: Oxaliplatin · Drug: S-1 · Biological: Trastuzumab
200 mg on Day 1 of each 3-week cycle as an IV infusion.
Also known as: Keytruda®, MK-3475
Solution for IV infusion on Day 1 of each 3-week cycle.
80 mg/m\^2 on Day 1 of each 3-week cycle as an IV infusion, administered as part of FP chemotherapy regimen.
800 mg/m\^2/day continuous on Days 1-5 of each 3-week cycle (120 hours or per local standard), administered as part of FP chemotherapy regimen.
130 mg/m\^2 on Day 1 of each 3-week cycle over 2 hours as an IV infusion, administered as part of CAPOX chemotherapy regimen and as part of SOX chemotherapy regimen.
1000 mg/m\^2 as oral capsules BID on Days 1-14 of each 3-week cycle, administered as part of CAPOX chemotherapy regimen.
Drug pages: Tegafur · Gimeracil · Oxonic Acid
Combination product of tegafur, CDHP, and Oxo. Oral capsules BID on Days 1-14 of each 3-week cycle based on body surface area (BSA): \<1.25 m\^2 BSA =40 mg, 1.25 to \<1.5 m\^2 BSA=50 mg, ≥1.5 m\^2 BSA=60 mg. Administered as part of SOX chemotherapy regimen.
8 mg/kg loading dose and then 6 mg/kg maintenance dose administered IV on day 1 of each 3-week cycle.
Also known as: Herceptin®
Progression Free Survival (PFS) Per RECIST 1.1 Assessed by BICR
PFS is defined as the time from randomization to the first documented disease progression per RECIST 1.1 as assessed by BICR or death due to any cause, whichever occurs first. Per RECIST 1.1, progressive disease (PD) is defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. The appearance of one or more new lesions is also considered progression. PFS was determined for first course pembrolizumab in the Global Cohort. Per statistical analysis plan, participants in the Japan-specific SOX Cohort were not included in the efficacy analysis.
Time frame: Up to 46 months
Overall Survival (OS)
OS is defined as the time from randomization to death due to any cause. OS was determined for first course pembrolizumab in the Global Cohort. Per statistical analysis plan, participants in the Japan-specific SOX Cohort were not included in the efficacy analysis.
Time frame: Up to 63 months
Objective Response Rate (ORR) Per RECIST 1.1 Assessed by BICR
ORR is defined as the percentage of participants who have a Complete Response (\[CR\], disappearance of all evidence of disease) or Partial Response (\[PR\], regression of measurable disease and no new sites) per RECIST 1.1 as assessed by blinded independent central review (BICR). ORR was determined for first course pembrolizumab in the Global Cohort. Per statistical analysis plan, participants in the Japan-specific SOX Cohort were not included in the efficacy analysis.
Time frame: Up to 63 months
Duration of Response (DOR) Per RECIST 1.1 Assessed by BICR
For participants who demonstrate CR or PR, DOR is defined as the time from first response (CR or PR) to subsequent disease progression or death from any cause, whichever occurs first. DOR was determined for first course pembrolizumab in the Global Cohort. Per statistical analysis plan, participants in the Japan-specific SOX Cohort were not included in the efficacy analysis.
Time frame: Up to 63 months
Number of Participants Who Experienced an Adverse Event (AE)
An AE is any untoward medical occurrence in a participant that is temporally associated with the use of study treatment, whether or not considered related to the study treatment. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study treatment. The number of participants who experienced an AE is reported for each treatment arm. Per statistical analysis plan, data from the second course of pembrolizumab was not included in the safety analysis.
Time frame: Up to 63 months
Number of Participants Who Discontinued Study Treatment Due to AEs
An AE is any untoward medical occurrence in a participant that is temporally associated with the use of study treatment, whether or not considered related to the study treatment. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study treatment. The number of participants who discontinued study treatment due to an AE is reported for each treatment arm. Per statistical analysis plan, data from the second course of pembrolizumab was not included in the safety analysis.
Time frame: Up to 63 months
| Milestone | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care | Japan Pembrolizumab + Trastuzumab + S-1 Plus Oxaliplatin | Japan Trastuzumab + S-1 Plus Oxaliplatin |
|---|---|---|---|---|
| Started | 350 | 348 | 20 | 20 |
| Treated | 350 | 346 | 20 | 20 |
| Received second course of pembrolizumab | 11 | 0 | 0 | 0 |
| Completed | 0 | 0 | 0 | 0 |
| Not completed | 350 | 348 | 20 | 20 |
| Withdrew: Death | 266 | 286 | 14 | 17 |
| Withdrew: Lost to follow-up | 0 | 1 | 0 | 0 |
| Withdrew: Withdrawal by subject | 1 | 3 | 0 | 0 |
| Withdrew: Participants ongoing | 83 | 58 | 6 | 3 |
PFS is defined as the time from randomization to the first documented disease progression per RECIST 1.1 as assessed by BICR or death due to any cause, whichever occurs first. Per RECIST 1.1, progressive disease (PD) is defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study. In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. The appearance of one or more new lesions is also considered progression. PFS was determined for first course pembrolizumab in the Global Cohort. Per statistical analysis plan, participants in the Japan-specific SOX Cohort were not included in the efficacy analysis.
| Months | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care |
|---|---|---|
| Progression Free Survival (PFS) Per RECIST 1.1 Assessed by BICR | 10.0 (8.6 to 12.2) | 8.1 (7.0 to 8.5) |
OS is defined as the time from randomization to death due to any cause. OS was determined for first course pembrolizumab in the Global Cohort. Per statistical analysis plan, participants in the Japan-specific SOX Cohort were not included in the efficacy analysis.
| Months | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care First Course |
|---|---|---|
| Overall Survival (OS) | 20.0 (17.8 to 22.1) | 16.8 (14.9 to 18.7) |
ORR is defined as the percentage of participants who have a Complete Response (\[CR\], disappearance of all evidence of disease) or Partial Response (\[PR\], regression of measurable disease and no new sites) per RECIST 1.1 as assessed by blinded independent central review (BICR). ORR was determined for first course pembrolizumab in the Global Cohort. Per statistical analysis plan, participants in the Japan-specific SOX Cohort were not included in the efficacy analysis.
| Percentage of Participants | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care First Course |
|---|---|---|
| Objective Response Rate (ORR) Per RECIST 1.1 Assessed by BICR | 72.6 (67.6 to 77.2) | 60.1 (54.7 to 65.2) |
For participants who demonstrate CR or PR, DOR is defined as the time from first response (CR or PR) to subsequent disease progression or death from any cause, whichever occurs first. DOR was determined for first course pembrolizumab in the Global Cohort. Per statistical analysis plan, participants in the Japan-specific SOX Cohort were not included in the efficacy analysis.
| Months | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care First Course |
|---|---|---|
| Duration of Response (DOR) Per RECIST 1.1 Assessed by BICR | 11.13 (9.8 to 12.7) | 9.5 (7.2 to 11.2) |
An AE is any untoward medical occurrence in a participant that is temporally associated with the use of study treatment, whether or not considered related to the study treatment. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study treatment. The number of participants who experienced an AE is reported for each treatment arm. Per statistical analysis plan, data from the second course of pembrolizumab was not included in the safety analysis.
| Participants | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care First Course | Japan Pembrolizumab + Trastuzumab + S-1 Plus Oxaliplatin | Japan Trastuzumab + S-1 Plus Oxaliplatin |
|---|---|---|---|---|
| Number of Participants Who Experienced an Adverse Event (AE) | 348 | 346 | 20 | 20 |
An AE is any untoward medical occurrence in a participant that is temporally associated with the use of study treatment, whether or not considered related to the study treatment. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study treatment. The number of participants who discontinued study treatment due to an AE is reported for each treatment arm. Per statistical analysis plan, data from the second course of pembrolizumab was not included in the safety analysis.
| Participants | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care First Course | Japan Pembrolizumab + Trastuzumab + S-1 Plus Oxaliplatin | Japan Trastuzumab + S-1 Plus Oxaliplatin |
|---|---|---|---|---|
| Number of Participants Who Discontinued Study Treatment Due to AEs | 150 | 136 | 11 | 11 |
Collected over Up to 63 months. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Global Pembrolizumab + Standard of Care First Course | 264/350 (75.4%) | 163/350 (46.6%) | 345/350 (98.6%) |
| Global Standard of Care | 288/348 (82.8%) | 159/346 (46%) | 338/346 (97.7%) |
| Japan Pembrolizumab + Trastuzumab + S-1 Plus Oxaliplatin | 14/20 (70%) | 10/20 (50%) | 20/20 (100%) |
| Japan Trastuzumab + S-1 Plus Oxaliplatin | 17/20 (85%) | 9/20 (45%) | 20/20 (100%) |
| Global Pembrolizumab + Standard of Care Second Course | 3/11 (27.3%) | 0/11 (0%) | 9/11 (81.8%) |
| Event | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care | Japan Pembrolizumab + Trastuzumab + S-1 Plus Oxaliplatin | Japan Trastuzumab + S-1 Plus Oxaliplatin | Global Pembrolizumab + Standard of Care Second Course |
|---|---|---|---|---|---|
| AnaemiaBlood and lymphatic system disorders | 5/350 | 3/346 | 2/20 | 0/20 | 0/11 |
| DiarrhoeaGastrointestinal disorders | 17/350 | 16/346 | 2/20 | 0/20 | 0/11 |
| PneumoniaInfections and infestations | 19/350 | 9/346 | 2/20 | 1/20 | 0/11 |
| Decreased appetiteMetabolism and nutrition disorders | 2/350 | 4/346 | 1/20 | 2/20 | 0/11 |
| DehydrationMetabolism and nutrition disorders | 2/350 | 4/346 | 2/20 | 1/20 | 0/11 |
| Febrile neutropeniaBlood and lymphatic system disorders | 1/350 | 2/346 | 1/20 | 0/20 | 0/11 |
| Acute myocardial infarctionCardiac disorders | 1/350 | 1/346 | 1/20 | 0/20 | 0/11 |
| Cardiac failureCardiac disorders | 1/350 | 0/346 | 1/20 | 0/20 | 0/11 |
| Ventricular tachycardiaCardiac disorders | 0/350 | 0/346 | 1/20 | 0/20 | 0/11 |
| ThyroiditisEndocrine disorders | 0/350 | 0/346 | 1/20 | 0/20 | 0/11 |
| Event | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care | Japan Pembrolizumab + Trastuzumab + S-1 Plus Oxaliplatin | Japan Trastuzumab + S-1 Plus Oxaliplatin | Global Pembrolizumab + Standard of Care Second Course |
|---|---|---|---|---|---|
| Neutrophil count decreasedInvestigations | 98/350 | 85/346 | 14/20 | 11/20 | 1/11 |
| Peripheral sensory neuropathyNervous system disorders | 85/350 | 73/346 | 14/20 | 14/20 | 0/11 |
| DiarrhoeaGastrointestinal disorders | 177/350 | 152/346 | 12/20 | 12/20 | 1/11 |
| Decreased appetiteMetabolism and nutrition disorders | 111/350 | 110/346 | 12/20 | 6/20 | 0/11 |
| NauseaGastrointestinal disorders | 167/350 | 164/346 | 9/20 | 11/20 | 2/11 |
| AnaemiaBlood and lymphatic system disorders | 157/350 | 159/346 | 5/20 | 4/20 | 2/11 |
| VomitingGastrointestinal disorders | 114/350 | 92/346 | 9/20 | 5/20 | 1/11 |
| DysgeusiaNervous system disorders | 17/350 | 16/346 | 9/20 | 4/20 | 0/11 |
| ConstipationGastrointestinal disorders | 62/350 | 68/346 | 8/20 | 5/20 | 0/11 |
| StomatitisGastrointestinal disorders | 39/350 | 30/346 | 8/20 | 1/20 | 0/11 |
| Age, Continuous(Years) | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care | Japan Pembrolizumab + Trastuzumab + S-1 Plus Oxaliplatin | Japan Trastuzumab + S-1 Plus Oxaliplatin | Total |
|---|---|---|---|---|---|
| Mean | 60.4 ± 11.8 | 61.7 ± 10.8 | 66.1 ± 12.8 | 64.1 ± 6.8 | 61.2 ± 11.3 |
| Sex: Female, Male(Participants) | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care | Japan Pembrolizumab + Trastuzumab + S-1 Plus Oxaliplatin | Japan Trastuzumab + S-1 Plus Oxaliplatin | Total |
|---|---|---|---|---|---|
| Female | 66 | 68 | 3 | 5 | 142 |
| Male | 284 | 280 | 17 | 15 | 596 |
| Ethnicity (NIH/OMB)(Participants) | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care | Japan Pembrolizumab + Trastuzumab + S-1 Plus Oxaliplatin | Japan Trastuzumab + S-1 Plus Oxaliplatin | Total |
|---|---|---|---|---|---|
| Hispanic or Latino | 38 | 45 | 1 | 1 | 85 |
| Not Hispanic or Latino | 309 | 293 | 19 | 19 | 640 |
| Unknown or Not Reported | 3 | 10 | 0 | 0 | 13 |
| Race (NIH/OMB)(Participants) | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care | Japan Pembrolizumab + Trastuzumab + S-1 Plus Oxaliplatin | Japan Trastuzumab + S-1 Plus Oxaliplatin | Total |
|---|---|---|---|---|---|
| American Indian or Alaska Native | 5 | 6 | 0 | 0 | 11 |
| Asian | 119 | 121 | 20 | 20 | 280 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 | 0 | 0 |
| Black or African American | 2 | 2 | 0 | 0 | 4 |
| White | 218 | 212 | 0 | 0 | 430 |
| More than one race | 6 | 5 | 0 | 0 | 11 |
| Unknown or Not Reported | 0 | 2 | 0 | 0 | 2 |
| Geographic Region(Participants) | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care | Japan Pembrolizumab + Trastuzumab + S-1 Plus Oxaliplatin | Japan Trastuzumab + S-1 Plus Oxaliplatin | Total |
|---|---|---|---|---|---|
| Western Europe/Israel/North America/Australia | 113 | 111 | 0 | 0 | 224 |
| Asia | 118 | 119 | 0 | 0 | 237 |
| Rest of the World | 119 | 118 | 0 | 0 | 237 |
| Japan | 0 | 0 | 20 | 20 | 40 |
| Programmed Cell Death Ligand 1 (PD-L1) Combined Positive Score (CPS) Status at Baseline(Participants) | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care | Japan Pembrolizumab + Trastuzumab + S-1 Plus Oxaliplatin | Japan Trastuzumab + S-1 Plus Oxaliplatin | Total |
|---|---|---|---|---|---|
| CPS≥1 | 298 | 296 | 16 | 17 | 627 |
| CPS<1 | 52 | 52 | 4 | 3 | 111 |
| Chemotherapy Regimen(Participants) | Global Pembrolizumab + Standard of Care First Course | Global Standard of Care | Japan Pembrolizumab + Trastuzumab + S-1 Plus Oxaliplatin | Japan Trastuzumab + S-1 Plus Oxaliplatin | Total |
|---|---|---|---|---|---|
| FP (cisplatin plus 5 fluorouracil) | 53 | 49 | 0 | 0 | 102 |
| CAPOX (capecitabine and oxaliplatin) | 297 | 299 | 0 | 0 | 596 |
| SOX (S-1 plus oxaliplatin) | 0 | 0 | 20 | 20 | 40 |
Showing the first 100 of 192 sites across 20 countries. Choose a country and city above to see the rest.
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: Yes — https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
Data sharing details ↗ · externaldatasharing-msd.com
Ran from Oct 2018 to primary completion in Mar 2024, 65 months.
Results were first posted in Mar 2025, 11 months after primary completion.
Of 45 industry-sponsored phase 3 interventional studies under Stomach Neoplasms, half reached primary completion within 45 months of starting (the median), counting those still running; a quarter within 32 and three quarters within 55. This study's 65 months is above that.
Counting every sponsor, half of 118 studies reached it within 52 months; a quarter within 39 and three quarters within 96.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Pembrolizumab