A Phase 3 interventional study of Rilvegostomig and Trastuzumab deruxtecan in HER2-positive Gastric Cancer and Gastroesophageal Junction Adenocarcinoma, sponsored by AstraZeneca. Recruiting at 304 sites in 28 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-16.
Sponsored by AstraZeneca · Phase 3, Interventional, and Treatment
This is a Phase Ⅲ, randomized, open-label, Sponsor-blinded, 3-arm, global, multicenter study assessing the efficacy and safety of rilvegostomig in combination with fluoropyrimidine and T-DXd (Arm A) compared to trastuzumab, chemotherapy, and pembrolizumab (Arm B) in HER2-positive locally advanced or metastatic gastric or GEJ adenocarcinoma participants whose tumors express PD L1 CPS ≥ 1. Rilvegostomig in combination with trastuzumab and chemotherapy will be evaluated in a separate arm (Arm C) to assess the contribution of each component in the experimental arm.
The purpose of this study is to assess the efficacy and safety of rilvegostomig in combination with fluoropyrimidine and T-DXd (Arm A) compared to trastuzumab, chemotherapy, and pembrolizumab (Arm B) in HER2-positive locally advanced or metastatic gastric or GEJ adenocarcinoma participants whose tumors express PD L1 CPS ≥ 1. Rilvegostomig in combination with trastuzumab and chemotherapy will be evaluated in a separate arm (Arm C) to assess the contribution of each component in the experimental arm.
This study will be conducted at up to 200-250 sites globally in approximately 25 countries.
3,399 studies on the registry are indexed under Stomach Neoplasms; 992 are open to participants now.
This study's planned enrollment of 840 is above the median of 66 across 2,499 interventional studies indexed under Stomach Neoplasms.
Browse Stomach Neoplasms studies →AstraZeneca is the lead sponsor of 3,499 studies on the registry; 270 are open to participants now.
Of its 368 completed or terminated interventional studies of FDA-regulated products, 178 (48%) have results posted.
Counted across the registry records on this site, refreshed daily.
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.
Exclusion Criteria:
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.
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.
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.
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.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
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 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.
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
A planned gap after a treatment, so that its effects can lessen before the study treatment or a study assessment. Ask the study team and the doctor who prescribed it before changing any medicine.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
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.
Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).
Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.
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.
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.
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.
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.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
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.
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.
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.
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.
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.
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.
LVEF (left ventricular ejection fraction)
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Washout period
A planned gap after a treatment, so that its effects can lessen before the study treatment or a study assessment. Ask the study team and the doctor who prescribed it before changing any medicine.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
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.
Brain metastases
Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).
Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.
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.
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.
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.
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.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
T-DXd + Rilvegostomig + Fluoropyrimidine (Capecitabine OR 5-FU)
Drug: Rilvegostomig · Drug: Trastuzumab deruxtecan · Drug: 5-fluorouracil · Drug: Capecitabine
Pembrolizumab + Trastuzumab + FP (5-FU plus cisplatin) or CAPOX (capecitabine plus oxaliplatin)
Drug: Trastuzumab · Drug: Pembrolizumab · Drug: 5-fluorouracil · Drug: Capecitabine · Drug: Cisplatin · Drug: Oxaliplatin
Rilvegostomig + Trastuzumab + FP (5-FU plus cisplatin) or CAPOX (capecitabine plus oxaliplatin)
Drug: Rilvegostomig · Drug: Trastuzumab · Drug: 5-fluorouracil · Drug: Capecitabine · Drug: Cisplatin · Drug: Oxaliplatin
Q3W, intravenous infusion
Also known as: AZD2936
Q3W, intravenous infusion
Also known as: T-DXd, DS-8201
Q3W, intravenous infusion
Q3W, intravenous infusion
Q3W, intravenous infusion
Also known as: 5-FU
BID, oral administration
Q3W, intravenous infusion
Q3W, intravenous infusion
Progression free survival (PFS)
PFS is defined as time from randomization until progression per RECIST v1.1, or death due to any cause.
Time frame: Up to approximately 6 years
Overall Survival (OS)
OS is defined as time from randomization until the date of death due to any cause.
Time frame: Up to approximately 6 years
Objective Response Rate (ORR)
ORR according to RECIST v1.1. ORR is defined as the proportion of participants who have a complete response (CR) or partial response (PR).
Time frame: Up to approximately 6 years
Duration of Response (DoR)
DoR according to RECIST v1.1. DoR will be defined as the time from the date of first documented response until date of documented progression per RECIST v1.1 or death due to any cause.
Time frame: Up to approximately 6 years
Proportion of all randomized participants alive and progression-free at 6 months (PFS6)
Proportion of all randomized participants alive and progression-free at 6 months calculated for progression.
Time frame: Up to 6 months
Proportion of all randomized participants alive and progression-free at 12 months (PFS12)
Proportion of all randomized participants alive and progression-free at 12 months calculated for progression.
Time frame: Up to 12 months
Time to second progression or death (PFS2)
PFS2 is defined as the time from randomization to the earliest of the progression event (following the initial progression), after the first subsequent therapy, or death, where the first objective progression includes progression occurring after 2 missed visits.
Time frame: Up to approximately 6 years
Occurrence of adverse events (AEs) and serious adverse events (SAEs)
Occurrence of AEs and SAEs will be graded according to the revised NCI CTCAE v5.0.
Time frame: Up to approximately 6 years
Pharmacokinetics (PK) of rilvegostomig, T-DXd, total anti-HER2 antibody, DXd, 5-FU, and capecitabine in serum
Concentration of rilvegostomig, T-DXd, total anti-HER2 antibody, DXd, fluoropyrimidine, and capecitabine in serum or plasma.
Time frame: Up to approximately 6 years
Immunogenicity of rilvegostomig and T-DXd assessed by the presence of antidrug antibodies (ADAs) for rilvegostomig and T-DXd
Presence of antidrug antibodies (ADAs) for rilvegostomig and T-DXd (confirmatory results: titers and neutralizing antibodies for confirmed positive samples).
Time frame: Up to approximately 6 years
Increase in enteral feeding assistance and eating difficulties
Time to first-confirmed worsening of eating symptoms or initiation of feeding assistance among all participants, as randomized.
Time frame: Up to approximately 6 years
Proportion of time on study intervention with high side-effect bother
Proportion of time on study intervention with high side-effect bother relative to low side-effect burden as measured by the Patient Global Impression of Treatment Tolerability (PGI-TT).
Time frame: Up to approximately 6 years
Overall Survival at 12 months (OS12)
Proportion of all randomized participants alive at 12 months.
Time frame: Up to 12 months
Overall Survival at 24 months (OS24)
Proportion of all randomized participants alive at 24 months.
Time frame: Up to 24 months
Pharmacokinetics (PK) of rilvegostomig, T-DXd, total anti-HER2 antibody, DXd, 5-FU, and capecitabine in serum
PK parameters (peak and trough concentrations).
Time frame: Up to approximately 6 years
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Not enrolling at this site — choose another above.
Showing the first 100 of 304 sites across 28 countries. Choose a country and city above to see the rest.
Plan to share: Yes — Qualified researchers can request access to anonymized individual patient-level data from AstraZeneca group of companies sponsored clinical trials via the request portal Vivli.org. All requests will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure. Yes, indicates that AZ are accepting requests for IPD, but this does not mean all requests will be shared.
Supporting information: Study protocol, Statistical analysis plan
Time frame: AstraZeneca will meet or exceed data availability as per the commitments made to the EFPIA PhRMA Data Sharing Principles. For details of our timelines, please refer to our disclosure commitment at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.
Access criteria: When a request has been approved AstraZeneca will provide access to the anonymized individual patient-level data via secure research environment Vivli.org. Signed Data Usage Agreement (non-negotiable contract for data accessors) must be in place before accessing requested information.
Data sharing details ↗ · vivli.org
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Studies of the drugs tested here: Rilvegostomig · Trastuzumab deruxtecan