A Phase 2 interventional study of Sonesitatug Vedotin and Rilvegostomig in Gastroesophageal Adenocarcinoma, sponsored by AstraZeneca. Recruiting at 70 sites in 11 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-03.
Sponsored by AstraZeneca · Phase 2, Interventional, and Treatment
GEMINI-PeriOp GC study will assess the safety, tolerability, pharmacokinetics (PK) and preliminary anti-tumor activity of novel agents or novel combinations as perioperative treatment in participants with locally advanced resectable gastric, gastroesophageal junction (GEJ), or esophageal adenocarcinoma who have not received previous treatment for the disease.
This Phase II, open-label, multi-drug, multi-center platform study consists of individual sub-studies/cohorts, each allows the assessment of multiple novel agents or novel combinations.
Participants will be assigned across different sub-studies/cohorts, to have sufficient evaluable participants of the confirmed recommended dose by Safety Review Committee (SRC) for study intervention in each corresponding sub-study/cohort.
3,399 studies on the registry are indexed under Stomach Neoplasms; 992 are open to participants now.
This study's planned enrollment of 100 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.
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.
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 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.
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.
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.
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 that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Participants will receive Sonesitatug Vedotin (Dose A) plus Rilvegostomig and 5-FU or Capecitabine as neoadjuvant combination therapy (pre-surgery period) and adjuvant therapy 1 and later will receive Sonesitatug vedotin (Dose A) plus Rilvegostomig as adjuvant therapy 2.
Drug: Sonesitatug Vedotin · Drug: Rilvegostomig · Drug: Capecitabine · Drug: 5-Fluorouracil (5-FU)
Participants will receive T-DXd plus Rilvegostomig and 5-FU or Capecitabine as neoadjuvant combination therapy (pre-surgery period) and adjuvant therapy 1 and later will receive Rilvegostomig as adjuvant therapy 2.
Drug: Rilvegostomig · Drug: Trastuzumab Deruxtecan (T-DXd) · Drug: Capecitabine · Drug: 5-Fluorouracil (5-FU)
Participants will receive Rilvegostomig plus FLOT chemotherapy as neoadjuvant combination therapy (pre-surgery period) and adjuvant therapy 1 and later will receive Rilvegostomig as adjuvant therapy 2.
Drug: Rilvegostomig · Drug: FLOT Chemotherapy
Participants will receive Sonesitatug vedotin (Dose B) plus Rilvegostomig and Capecitabine as neoadjuvant combination therapy (pre-surgery period) and adjuvant therapy 1 and later will receive Sonesitatug vedotin (Dose B) plus Rilvegostomig as adjuvant therapy 2.
Drug: Sonesitatug Vedotin · Drug: Rilvegostomig · Drug: Capecitabine
Participants will receive Sonesitatug Vedotin (Dose C) plus Rilvegostomig plus 5-FU and calcium folinate as neoadjuvant combination therapy (pre-surgery period) and adjuvant therapy 1 and later will receive Sonesitatug vedotin (Dose C) plus Rilvegostomig as adjuvant therapy 2.
Drug: Sonesitatug Vedotin · Drug: Rilvegostomig · Drug: 5-Fluorouracil (5-FU) · Drug: Calcium folinate
Sonesitatug Vedotin will be administered as an IV infusion.
Also known as: AZD0901
Rilvegostomig will be administered as an IV infusion.
Also known as: AZD2936
T-DXd will be administered as an IV infusion.
Also known as: DS-8201a
Capecitabine (Fluoropyrimidine) will be administered orally as chemotherapy standard of care.
5-FU (Fluoropyrimidine) will be administered as a continuous IV infusion as chemotherapy standard of care.
Drug pages: Fluorouracil · Leucovorin · Oxaliplatin · Docetaxel
FLOT (5-FU, leucovorin, oxaliplatin, and docetaxel) Chemotherapy will be administered as an IV infusion.
Calcium folinate will be administered as an IV infusion as chemotherapy standard of care.
Also known as: Leucovorin
Number of participants with adverse events (AEs) and serious adverse events (SAEs)
To assess the safety and tolerability of perioperative treatment.
Time frame: Until sub-study completion, up to 38 months
Percentage of participants with pathological complete response (pCR)
pCR is defined as no viable cancer cells, including lymph nodes after complete evaluation in the resected gastric, GEJ, or esophageal cancer specimen and all sampled regional lymph nodes following neoadjuvant treatment.
Time frame: Until sub-study completion, up to 38 months
Surgery completion rate
Surgery completion rate is defined as the percentage of participants who received gastrectomy or gastroesophagectomy or esophagectomy.
Time frame: Until sub-study completion, up to 38 months
R0 resection (complete resection) rate
R0 resection (complete resection) rate is the percentage of participants who received gastrectomy or gastroesophagectomy or esophagectomy and had a confirmed margin-negative resection.
Time frame: Until sub-study completion, up to 38 months
Percentage of participants with tumor downstaging
Tumor downstaging is defined as the lowering of the primary tumor (T) and/or regional lymph nodes (N) from pre-neoadjuvant clinical staging (pre-cTN) to post-neoadjuvant clinical staging (post-cTN) and to postoperative pathological staging (ypTN).
Time frame: Until sub-study completion, up to 38 months
Event-free survival (EFS)
EFS is defined as the time from the first dose of study intervention to documented Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1) or non-RECIST 1.1 disease progression that precludes radical surgery or requires non-protocol therapy during the neoadjuvant through surgery period, or to documented RECIST 1.1 or biopsy-confirmed non-RECIST 1.1 recurrence or progression of disease during the adjuvant period, or death due to any cause at any time.
Time frame: Until sub-study completion, up to 38 months
Disease-free survival (DFS)
DFS is defined as the time elapsed from the date of the first post-surgery scan (ie, Adjuvant Baseline scan) until the date of first evidence of disease recurrence as determined by Investigator using RECIST 1.1 assessment (local or distant), or death due to any cause, whichever occurs first.
Time frame: Until sub-study completion, up to 38 months
Objective response rate (ORR)
ORR is defined as the percentage of participants who have a CR or PR as determined by Investigator using RECIST 1.1 at their latest assessment prior to surgery.
Time frame: Until sub-study completion, up to 38 months
Overall survival (OS)
OS is defined as the time from the first dose of the study intervention until the date of death due to any cause regardless of whether participant withdraws from treatment or receives another anti-cancer therapy.
Time frame: Until sub-study completion, up to 38 months
Serum concentrations of study interventions
To assess the serum concentrations of study interventions in participants receiving perioperative treatment.
Time frame: Until sub-study completion, up to 38 months
Number of participants with positive anti-drug antibodies (ADA)
To assess the immunogenicity of study interventions in participants receiving perioperative treatment.
Time frame: Until sub-study completion, up to 38 months
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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.
Started Jul 2025 (actual). Primary completion is estimated for Nov 2027, 27 months after the start.
Of 65 industry-sponsored phase 2 interventional studies under Stomach Neoplasms, half reached primary completion within 38 months of starting (the median), counting those still running; a quarter within 25 and three quarters within 68. This study's planned 27 months is below that.
Counting every sponsor, half of 358 studies reached it within 50 months; a quarter within 31 and three quarters within 75.
How these figures are worked out, and which studies are left out of them.
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.
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Studies of the drugs tested here: Sonesitatug vedotin · Trastuzumab deruxtecan · Capecitabine · Fluorouracil · Leucovorin · Oxaliplatin · Docetaxel