Study of TDXd, Chemotherapy, Pembrolizumab, and Trastuzumab in First-Line Metastatic HER2-Positiv… (NCT06731478) | Clinical Trial Compass
RecruitingPhase 3
Study of TDXd, Chemotherapy, Pembrolizumab, and Trastuzumab in First-Line Metastatic HER2-Positive Gastric or Gastroesophageal Junction Cancer
United States, Argentina, Australia726 participantsStarted 2025-02-27
Plain-language summary
This clinical trial is designed to assess the efficacy and safety of the triplet combination of trastuzumab deruxtecan (ENHERTU, T-DXd, DS-8201a) plus a fluoropyrimidine plus pembrolizumab versus standard of care (SoC) chemotherapy plus trastuzumab plus pembrolizumab as first-line therapy in participants with unresectable, locally advanced or metastatic HER2-positive tumor PD-L1 CPS ≥1 gastric or GEJ cancer in the Main Cohort. An Exploratory Cohort will also be evaluated to assess the efficacy and safety of T-DXd plus a fluoropyrimidine versus SoC chemotherapy plus trastuzumab in participants with unresectable, locally advanced or metastatic HER2-positive tumor PD-L1 CPS \<1 gastric or GEJ cancer.
Who can participate
Age range
18 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Sign and date the Tissue Prescreening ICF, prior to HER2 and PD-L1 CPS central testing. Sign and date the Main Screening ICF, prior to the start of any trial-specific qualification procedures. Sign and date the Optional PGx ICF (included in the Main Screening ICF) prior to any PGx procedure.
. Adults ≥18 years of age on the day of signing the ICF. Follow local regulatory requirements if the legal age of consent for trial participation is \>18 years old.
. Previously untreated, unresectable, locally advanced or metastatic gastric or GEJ adenocarcinoma histologically confirmed by pathology report. Prior treatment in the perioperative and/or adjuvant setting is permissible, provided there is \>6 months between the end of perioperative or neoadjuvant treatment and the diagnosis of recurrent disease.
. Centrally determined HER2-positive (IHC 3+ or IHC 2+/ISH-positive) gastric or GEJ cancer as classified by the American Society of Clinical Oncology-College of American Pathologists for GC on a tumor biopsy as detected by prospective central test on new (core, incisional, excisional biopsy) or existing tumor tissue taken at the time of diagnosis of locally advanced or metastatic disease.
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Progression Free Survival (PFS)
Timeframe: From date of randomization to the date of radiographic disease progression or death due to any cause, up to 59 months
. All participants must provide a tumor sample for tissue-based IHC staining to centrally determine HER2 expression, PD-L1 CPS, and other correlatives. The mandatory FFPE tumor sample can be from either the primary tumor or metastatic biopsy. Specimens with limited tumor content (as centrally determined) and cytology samples are inadequate for defining tumor HER2 and PD-L1 status.
. At least 1 target measurable lesion on CT or MRI, assessed by the investigator based on RECIST v1.1. Lesions situated in a previously irradiated area are considered measurable if progression has been shown in such lesions.
. LVEF ≥50% within 28 days before randomization.
Exclusion criteria
. Prior exposure to other HER2-targeting therapies (including ADCs).
. Lack of physiological integrity of the upper gastrointestinal tract (ie, severe Crohn disease that results in malabsorption) or malabsorption syndrome that would preclude feasibility of oral chemotherapy (ie, capecitabine).
. Known DPD enzyme deficiency. Note: Screening for DPD enzyme deficiency is required only in regions/countries where DPD testing is SoC and with unknown DPD status. For regions/countries where DPD testing is not SoC, local practice should be followed.
. Contraindications to trastuzumab, 5-FU, capecitabine, cisplatin, or oxaliplatin treatment as per local label.
. Medical history of myocardial infarction within 6 months before randomization or symptomatic CHF (New York Heart Association Class II to IV). Participants with troponin levels above ULN at Screening (as defined by the manufacturer) and without any myocardial infarction -related symptoms should have a cardiologic consultation during the Screening Period to rule out myocardial infarction.
. Has a corrected QT interval (QTcF) prolongation to \>470 ms (females) or \>450 ms (males) based on the average of the screening triplicate 12-lead ECG.
. Has a history of (non-infectious) ILD/pneumonitis that required steroids, has current ILD/pneumonitis, or where suspected ILD/pneumonitis cannot be ruled out by imaging at Screening
. Lung-specific intercurrent clinically significant illnesses including, but not limited to, any underlying pulmonary disorder (eg, pulmonary emboli within 3 months of the trial randomization, severe asthma, severe chronic obstructive pulmonary disease, restrictive lung disease, pleural effusion, etc).