A Phase 1/2 interventional study of Zongertinib and Trastuzumab deruxtecan in Metastatic Breast Cancer, Metastatic Gastric Adenocarcinoma and Gastroesophageal Junction Adenocarcinoma, sponsored by Boehringer Ingelheim. Recruiting at 104 sites in 10 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-05.
Sponsored by Boehringer Ingelheim · Phase 1/2, Interventional, and Treatment
This study is open to adults aged 18 years and older with different types of HER2+ cancer that has spread and cannot be removed by surgery. People can take part in this study if their tumours show HER2 aberrations and previous treatment was not successful. The purpose of this study is to find a suitable dose of zongertinib that people with different types of HER2+ cancer that has spread can tolerate best when taken alone or together with trastuzumab deruxtecan (T-DXd), with trastuzumab emtansine (T-DM1), with trastuzumab with or without capecitabine, with zanidatamab with or without docetaxel, or with mFOLFOX6 (with or without trastuzumab). Another purpose is to check whether zongertinib alone and in combination with other treatments can make tumours shrink. Zongertinib inhibits HER2. HER2 causes cancer cells to grow.
In this study, participants receive treatment in cycles. Study participants are treated with zongertinib alone or in combination with other treatments. This study has 2 parts. In Part 1, participants in different groups receive increasing doses of zongertinib. In Part 2, participants are put into different groups by chance. Each group receives a different dose of zongertinib. Every participant has an equal chance of being in each group.
During the study, the participants visit the study site regularly. In this study, researchers want to find the highest dose of zongertinib that participants can tolerate when taken alone or together with other treatments. To find this out, researchers look at certain severe health problems that a number of participants have. The doctors regularly check the size of the tumour with imaging methods (CT/MRI) during the study. The doctors also regularly check participants' health and take note of any unwanted effects.
14,825 studies on the registry are indexed under Breast Neoplasms; 3,319 are open to participants now.
This study's planned enrollment of 910 is above the median of 72 across 10,896 interventional studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →Boehringer Ingelheim is the lead sponsor of 2,304 studies on the registry; 62 are open to participants now.
Of its 167 completed or terminated interventional studies of FDA-regulated products, 123 (74%) have results posted.
Counted across the registry records on this site, refreshed daily.
The criteria were revised on the registry on Oct 28, 2026. See what changed
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.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
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.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
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.
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.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
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.
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.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
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.
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.
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.
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.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
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.
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.
Dose escalation (Phase Ib)
Drug: Zongertinib · Drug: Trastuzumab emtansine
Dose escalation (Phase Ib)
Drug: Zongertinib · Drug: Trastuzumab deruxtecan
Dose escalation (Phase Ib)
Drug: Zongertinib · Drug: Trastuzumab deruxtecan
Dose optimization (Phase II).
Drug: Zongertinib · Drug: Trastuzumab emtansine
Dose optimization (Phase II).
Drug: Zongertinib · Drug: Trastuzumab deruxtecan
Dose optimization (Phase II).
Drug: Zongertinib · Drug: Trastuzumab deruxtecan
Dose escalation (Phase Ib)
Drug: Zongertinib · Drug: Trastuzumab · Drug: Capecitabine
Dose escalation (Phase Ib)
Drug: Zongertinib · Drug: Trastuzumab
Dose optimization (Phase II).
Drug: Zongertinib · Drug: Trastuzumab · Drug: Capecitabine
Dose optimization (Phase II).
Drug: Zongertinib
Dose optimization (Phase II).
Drug: Zongertinib · Drug: Trastuzumab
Extension Phase II
Drug: Zongertinib
Extension Phase II
Drug: Zongertinib · Drug: Trastuzumab
Dose escalation (Phase Ib)
Drug: Zongertinib · Drug: mFOLFOX6
Dose escalation (Phase Ib)
Drug: Zongertinib · Drug: Trastuzumab · Drug: mFOLFOX6
Dose escalation (Phase Ib) - is not conducted in China or South Korea
Drug: Zongertinib · Drug: zanidatamab
Dose escalation (Phase 1b) - is not conducted in China or South Korea
Drug: Zongertinib · Drug: zanidatamab · Drug: Docetaxel
Dose justification (Phase II)
Drug: Zongertinib · Drug: Trastuzumab
Extension Phase II
Drug: Zongertinib · Drug: Trastuzumab
Zongertinib
Also known as: BI 1810631, Hernexeos®
Trastuzumab deruxtecan
Also known as: T-DXd; Enhertu®
Trastuzumab emtansine
Also known as: T-DM1; Kadcyla®
Trastuzumab
Also known as: Herceptin®
Capecitabine
mFOLFOX6 (oxaliplatin, calcium folinate, 5-fluorouracil)
zanidatamab
Docetaxel
Dose escalation (Phase Ib): Occurrence of dose-limiting toxicities (DLTs) in the maximum tolerated dose (MTD) evaluation period
The MTD evaluation period is defined as the first 21 days of the first treatment cycle for Cohorts A, B, C, G, K, O and P. The MTD evaluation period is defined as the first 28 days after the first administration of any trial medication for Cohorts M and N.
Time frame: up to 21 days
Dose optimization and justification (Phase II): Objective response (OR)
Objective response (OR) is defined as the best overall response of confirmed complete response (CR) or confirmed partial response (PR) according to RECIST 1.1 from the date of treatment start until the earliest date of disease progression, death, or last evaluable tumor assessment before start of subsequent anti-cancer therapy, or treatment discontinuation as assessed by investigator review.
Time frame: up to 50 months
Dose escalation (Phase Ib): Objective response (OR)
Time frame: up to 50 months
Dose escalation (Phase Ib): Occurrence of dose-limiting toxicities (DLTs) during the entire treatment period
Time frame: up to 50 months
Dose escalation (Phase Ib): Maximum measured concentration of zongertinib (at steady state) (Cmax,(ss))
For cycle 2 only.
Time frame: up to 2 days
Dose escalation (Phase Ib): Area under the concentration-time curve of zongertinib over the time interval from 0 to 4h at steady state (AUC0-4h,ss)
For cycle 2 only.
Time frame: up to 2 days
Dose escalation (Phase Ib): Area under the concentration-time curve of zongertinib over the time interval from 0 to the last quantifiable data point at steady state (AUC0-tz,ss)
For cycle 2 only.
Time frame: up to 2 days
Dose optimization and justification (Phase II): Progression-free survival (PFS)
PFS is defined as the time from treatment start until the earliest date of tumor progression according RECIST 1.1 based on investigator review or death from any cause, whichever occurs first.
Time frame: up to 50 months
Dose optimization and justification (Phase II): Disease control (DC)
DC is defined as best overall response of confirmed complete response (CR) or confirmed partial response (PR) or stable disease (SD) where best overall response is defined according to RECIST 1.1 from first treatment administration until the earliest of disease progression, death, or last evaluable tumor assessment before start of subsequent anti-cancer therapy, or treatment discontinuation, as assessed by investigator review.
Time frame: up to 50 months
Dose optimization and justification (Phase II): Occurrence of treatment-emergent AEs leading to zongertinib (BI 1810631) dose reduction during the on-treatment period
Time frame: up to 50 months
Dose optimization and justification (Phase II): Maximum measured concentration (at steady state) (Cmax,(ss))
Time frame: up to 50 months
Dose optimization and justification (Phase II): Area under the concentration-time curve over the time interval from 0 to the last quantifiable data point at steady state (AUC0-tz,ss)
Time frame: up to 50 months
Dose optimization and justification (Phase II): Patient-reported outcome (PRO) - PRO-CTCAE
The Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) item library was developed to elicit symptomatic toxicity information directly from patients in cancer clinical trials. The items selected for this trial are: Mouth/throat sores, Taste changes, Decreased appetite, Nausea, Vomiting, Constipation, Diarrhoea, Shortness of breath, Cough, Rash, Skin dryness, Hair loss, Itching, Numbness \& Tingling, Fatigue, Nosebleed, Headache. PRO-CTCAE responses are scored from 0 (=none) to 4 (=very severe) (or 0/1 for absent/present).
Time frame: up to 24 weeks
Dose optimization and justification (Phase II): Patient-reported outcome (PRO) - EORTC IL46
The EORTC IL46 is a single question that assesses bother (burden) of treatment. It is rated on a scale from 1 to 4, ranging from "not at all" to "very much".
Time frame: up to 48 weeks
Dose optimization and justification (Phase II): Patient-reported outcome (PRO) - EORTC IL19
The EORTC IL19 consists of five physical functioning scale items. It is rated on a scale from 1 to 4, ranging from "not at all" to "very much".
Time frame: up to 48 weeks
Not enrolling at this site — choose another above.
Showing the first 100 of 104 sites across 10 countries. Choose a country and city above to see the rest.
Plan to share: Yes — Once the criteria in section "Time Frame" are fulfilled, researchers can use the following link https://www.clinicalstudies.boehringer-ingelheim.com/msw/datasharing to request access to the clinical study documents regarding this study, and upon a signed "Document Sharing Agreement". Furthermore, researchers can request access to the clinical study data, for this and other listed studies, after the submission of a research proposal and according to the terms outlined in the website.
Supporting information: Study protocol, Statistical analysis plan, Clinical study report
Time frame: One year after the approval has been granted by major Regulatory Authorities and after the primary manuscript has been accepted for publication, or after termination of the development program.
Access criteria: For study documents - upon signing of a 'Document Sharing Agreement'. For study data - 1. after the submission and approval of the research proposal (checks will be performed by the sponsor and/or the independent review panel, including checking that the planned analysis does not compete with sponsor's publication plan); 2. and upon signing of a legal agreement.
Data sharing details ↗ · www.clinicalstudies.boehringer-ingelheim.com
Started Jun 2024 (actual). Primary completion is estimated for Jan 2029, 54 months after the start.
Of 161 industry-sponsored phase 1/2 interventional studies under Breast Neoplasms, half reached primary completion within 59 months of starting (the median), counting those still running; a quarter within 44 and three quarters within 75. This study's planned 54 months is close to that.
Counting every sponsor, half of 327 studies reached it within 61 months; a quarter within 45 and three quarters within 88.
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 drug tested here: Zongertinib