A Phase 1/2 interventional study of Zanidatamab and Docetaxel in Breast Cancer, Gastric Cancer and Gastroesophageal Junction Cancer, sponsored by BeiGene. Completed at 21 sites in 3 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-02.
Sponsored by BeiGene · Phase 1/2, Interventional, and Treatment
The purpose of the study is to assess the safety, tolerability and preliminary antitumor activity of zanidatamab in combination with docetaxel in participants with human epidermal growth factor receptor 2 (HER2)-positive breast cancer, and zanidatamab in combination with tislelizumab and chemotherapy in participants with HER2-positive gastric/gastroesophageal Junction (GEJ) adenocarcinoma
14,825 studies on the registry are indexed under Breast Neoplasms; 3,319 are open to participants now.
This study's enrollment of 71 is close to the median of 72 across 10,896 interventional studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →BeiGene is the lead sponsor of 125 studies on the registry; 2 are open to participants now.
Of its 55 completed or terminated interventional studies of FDA-regulated products, 32 (58%) have results posted.
Counted across the registry records on this site, refreshed daily.
Key Inclusion Criteria:
Disease diagnosis and prior treatment:
Cohort 1 (the breast cancer treatment cohort):
Cohort 2 (the first-line gastric/gastroesophageal junction adenocarcinoma treatment cohort):
Key Exclusion Criteria:
History of approved or investigative tyrosine kinase/HER inhibitors in any treatment setting
a. except trastuzumab with or without pertuzumab used in or adjuvant setting for Cohort 1
Note: Participants who are currently or have previously been on any of the following steroid regimens are not excluded:
NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.
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.
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
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.
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.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
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.
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.
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.
Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.
Cancer that has spread to the leptomeninges, the thin layers covering the brain and spinal cord, and the fluid between them. It is not the same as brain metastases.
Criteria often treat it separately, and many studies leave it out even where treated brain metastases are allowed.
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.
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.
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.
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.
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.
Line of therapy
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
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.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
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.
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.
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.
Adjuvant and neoadjuvant
Neoadjuvant treatment is given before the main treatment (usually surgery), often to shrink a tumour. Adjuvant treatment is given after it, to lower the chance of the cancer coming back.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Leptomeningeal disease
Cancer that has spread to the leptomeninges, the thin layers covering the brain and spinal cord, and the fluid between them. It is not the same as brain metastases.
Criteria often treat it separately, and many studies leave it out even where treated brain metastases are allowed.
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.
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.
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.
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.
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.
Participants with HER2+ breast cancer received zanidatamab 30 mg/kg intravenously (IV) and docetaxel 75 mg/m\^2 IV once every 3 weeks (Q3W) for an initial period of up to six cycles. After cycle 6, continuation of docetaxel treatment was at the discretion of the investigator. Zanidatamab was administered until disease progression, intolerable toxicity, or another criterion for treatment discontinuation was met.
Biological: Zanidatamab · Drug: Docetaxel
Participants with HER2+ breast cancer received zanidatamab 1800 mg/kg IV and docetaxel 75 mg/m\^2 IV Q3W for an initial period of up to six cycles. After cycle 6, continuation of docetaxel treatment was at the discretion of the investigator. Zanidatamab was administered until disease progression, intolerable toxicity, or another criterion for treatment discontinuation was met.
Biological: Zanidatamab · Drug: Docetaxel
Participants with HER2+ gastric / gastroesophageal junction cancer (GEJC) received zanidatamab 30 mg/kg IV and tislelizumab 200 mg IV once every 3 weeks until disease progression, intolerable toxicity, or another criterion for treatment discontinuation was met. Participants also received CAPOX chemotherapy (1000 mg/m\^2 oral capecitabine twice daily for 14 days in each cycle and 130 mg/m\^2 oxaliplatin IV once every 3 weeks) for up to 6 six cycles. After cycle 6, oxaliplatin was discontinued and continuation of capecitabine as maintenance treatment was at the investigator's discretion.
Biological: Zanidatamab · Biological: Tislelizumab · Drug: Capecitabine · Drug: Oxaliplatin
Participants with HER2+ gastric / GEJC received zanidatamab 1800 mg (participants with body weight \< 70 kg) or 2400 mg (participants with body weight ≥ 70 kg) IV and tislelizumab 200 mg IV Q3W until disease progression, intolerable toxicity, or another criterion for treatment discontinuation was met. Participants also received CAPOX chemotherapy (1000 mg/m\^2 oral capecitabine twice daily for 14 days in each cycle and 130 mg/m\^2 oxaliplatin IV once every 3 weeks) for up to 6 six cycles. After cycle 6, oxaliplatin was discontinued and continuation of capecitabine as maintenance treatment was at the investigator's discretion.
Biological: Zanidatamab · Biological: Tislelizumab · Drug: Capecitabine · Drug: Oxaliplatin
Administered intravenously
Also known as: ZW25
Administered intravenously
Administered intravenously
Also known as: BGB-A317
Administered orally
Administered intravenously
Number of Participants Experiencing Adverse Events (AEs) and Serious Adverse Events (SAEs)
An AE is defined as any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of study treatments, whether considered related to study treatments or not. A serious AE (SAE) was any untoward medical occurrence that, at any dose - resulted in death, - was life threatening, - required hospitalization or prolongation of existing hospitalization, - resulted in disability/incapacity, - was a congenital anomaly/birth defect.
Time frame: From the first dose of study drug(s) to 30 days after the last dose; up to approximately 42 months
Objective Response Rate (ORR)
ORR is defined as the percentage of participants who had a best overall response of complete response or partial response per the Response Evaluation Criteria in Solid Tumors (RECIST) Version 1.1. Complete Response (CR): Disappearance of all target lesions. Any pathological lymph nodes (whether target or non-target) must have reduction in short axis to \< 10 mm. Partial Response (PR): At least a 30% decrease in the sum of diameters of target lesions, taking as reference the baseline sum diameters.
Time frame: Response was assessed every 6 weeks from cycle 1 day 1 for the first 36 weeks and then every 12 weeks thereafter; maximum time on study follow-up was 42months.
Duration of Response (DOR)
DOR is defined as the time from the first determination of an objective response until the first documentation of disease progression or death, whichever occurred first.
Time frame: From the start date of study treatment to the first documentation of progression or death, whichever occurs first, up to approximately 42 months
Time to Response (TTR)
Time to response is defined as the time from the start date of study treatment to the first determination of an objective response assessed by investigator per RECIST v 1.1.
Time frame: From the start date of study treatment to the first documentation of response, whichever occurs first, up to approximately 42 months
Progression-free Survival (PFS)
PFS is defined as the time from the start date of study drug to the date of the first objectively documented tumor progression assessed by investigator per RECIST Version 1.1 or death, whichever occurred first.
Time frame: From the start date of study treatment to the first documentation of progression or death, whichever occurs first, up to approximately 42 months
Disease Control Rate (DCR)
DCR is defined as the percentage of participants with best overall response (BOR) of CR, PR, and stable disease by investigator per RECIST Version 1.1. BOR is the best response recorded from the start of the study drug treatment until the end of treatment taking into account any requirement for confirmation.
Time frame: Response was assessed every 6 weeks from cycle 1 day 1 for the first 36 weeks and then every 12 weeks thereafter; maximum time on study follow-up was 42 months.
Overall Survival (OS)
Time from the start date of study drug to the date of death due to any cause.
Time frame: From the start date of study treatment to the documented death date or the last known alive date, up to approximately 41 months
Serum Concentration of Zanidatamab as a Function of Time
Time frame: Day 1 end of infusion of Cycle 1, 2, 5, 9, 17, 26 and 35. Each cycle is 21 days
Area Under the Plasma Concentration-time Curve From Time Zero to the Last Measurable Timepoint (AUC(0-t)) of Zanidatamab
Time frame: Cycle 1: predose and 0, 2, 4, 24, 96, 168, and 336 hours postdose. Cycle 2: predose and 0, 168, and 336 hours postdose. Each cycle is 21 days.
Observed Maximum Plasma Concentration of Zanidatamab During a Sample Interval (Cmax)
Time frame: Cycle 1: predose and 0, 2, 4, 24, 96, 168, and 336 hours postdose. Cycle 2: predose and 0, 168, and 336 hours postdose. Each cycle is 21 days.
Observed Time to Maximum Plasma Concentration of Zanidatamab During a Sampling Interval (Tmax)
Time frame: Cycle 1: predose and 0, 2, 4, 24, 96, 168, and 336 hours postdose. Cycle 2: predose and 0, 168, and 336 hours postdose. Each cycle is 21 days.
Terminal Elimination Half-life (t1/2) of Zanidatamab
Time frame: Cycle 1: predose and 0, 2, 4, 24, 96, 168, and 336 hours postdose. Cycle 2: predose and 0, 168, and 336 hours postdose. Each cycle is 21 days.
Apparent Clearance After Oral Administration (CL/F) of Zanidatamab
Time frame: Cycle 1: predose and 0, 2, 4, 24, 96, 168, and 336 hours postdose
Number of Participants With Anti-zanidatamab Antibodies
Time frame: From the first dose of study drug(s) to 30 days after the last dose; up to approximately 42 months
Number of Participants With AEs and SAEs in Participants Who Entered the Long-term Extension Period
Time frame: From the first dose of study drug(s) to 30 days after the last dose; up to approximately 51 months
The study was conducted at 22 study centers in China, Korea, and Taiwan; 22 centers enrolled a total of 71 participants.
| Milestone | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC : Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Started | 11 | 27 | 19 | 14 |
| Completed | 4 | 20 | 5 | 7 |
| Not completed | 7 | 7 | 14 | 7 |
| Withdrew: Withdrawal by subject | 4 | 2 | 3 | 1 |
| Withdrew: Death | 2 | 3 | 11 | 5 |
| Withdrew: Lost to follow-up | 1 | 1 | 0 | 1 |
| Withdrew: Physician decision | 0 | 1 | 0 | 0 |
An AE is defined as any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of study treatments, whether considered related to study treatments or not. A serious AE (SAE) was any untoward medical occurrence that, at any dose - resulted in death, - was life threatening, - required hospitalization or prolongation of existing hospitalization, - resulted in disability/incapacity, - was a congenital anomaly/birth defect.
| Participants | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Number of Participants experiencing AEs | 11 | 27 | 19 | 14 |
| Number of Participants experiencing SAEs | 2 | 10 | 12 | 5 |
ORR is defined as the percentage of participants who had a best overall response of complete response or partial response per the Response Evaluation Criteria in Solid Tumors (RECIST) Version 1.1. Complete Response (CR): Disappearance of all target lesions. Any pathological lymph nodes (whether target or non-target) must have reduction in short axis to \< 10 mm. Partial Response (PR): At least a 30% decrease in the sum of diameters of target lesions, taking as reference the baseline sum diameters.
| Percentage of participants | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Objective Response Rate (ORR) | 100.0 (63.1 to 100) | 88.0 (68.8 to 97.5) | 78.9 (54.4 to 93.9) | 71.4 (41.9 to 91.6) |
DOR is defined as the time from the first determination of an objective response until the first documentation of disease progression or death, whichever occurred first.
| months | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC : Zanidatamab 1800/2400mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Duration of Response (DOR) | 12.4 (5.5 to NA) | 23.5 (11.3 to NA) | 15.4 (4.9 to NA) | 23.7 (7.4 to NA) |
Time to response is defined as the time from the start date of study treatment to the first determination of an objective response assessed by investigator per RECIST v 1.1.
| Weeks | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Time to Response (TTR) | 5.71 (5.36 to 6.00) | 6.00 (5.71 to 7.00) | 5.71 (5.43 to 11.00) | 6.14 (5.29 to 6.14) |
PFS is defined as the time from the start date of study drug to the date of the first objectively documented tumor progression assessed by investigator per RECIST Version 1.1 or death, whichever occurred first.
| months | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Progression-free Survival (PFS) | 13.7 (6.8 to NA) | 22.1 (12.7 to NA) | 8.3 (5.6 to 32.4) | 24.6 (8.8 to NA) |
DCR is defined as the percentage of participants with best overall response (BOR) of CR, PR, and stable disease by investigator per RECIST Version 1.1. BOR is the best response recorded from the start of the study drug treatment until the end of treatment taking into account any requirement for confirmation.
| Percentage of participants | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Disease Control Rate (DCR) | 100.0 (63.1 to 100.0) | 96.0 (79.6 to 99.9) | 100.0 (82.4 to 100.0) | 100.0 (76.8 to 100.0) |
Time from the start date of study drug to the date of death due to any cause.
| months | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Overall Survival (OS) | NA (36.9 to NA) | NA (NA to NA) | 31.4 (9.4 to NA) | NA (11.8 to NA) |
| µg/ml | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Cycle 1 Day 1 End of Infusion (Peak) | 665.73 ± 146.655 | 639.57 ± 205.989 | 550.78 ± 153.770 | 514.69 ± 118.776 |
| Cycle 2 Day 1 End of Infusion (Peak) | 759.44 ± 119.484 | 743.56 ± 112.107 | 608.75 ± 111.424 | 614.15 ± 89.763 |
| Cycle 5 Day 1 End of Infusion (Peak) | 830.20 ± 180.227 | 778.48 ± 95.597 | 648.38 ± 133.648 | 667.15 ± 150.823 |
| Cycle 9 Day 1 End of Infusion (Peak) | 962.20 ± 129.808 | 817.23 ± 180.142 | 705.64 ± 149.080 | 663.45 ± 121.904 |
| Cycle 17 Day 1 End of Infusion (Peak) | 1022.75 ± 134.525 | 840.18 ± 198.200 | 762.50 ± 109.983 | 734.88 ± 119.881 |
| Cycle 26 Day 1 End of Infusion (Peak) | 1050.67 ± 114.374 | 743.33 ± 148.520 | 683.80 ± 175.189 | 740.43 ± 160.651 |
| Cycle 35 Day 1 End of Infusion (Peak) | 950.00 ± 21.378 | 908.60 ± 163.032 | 669.40 ± 230.838 | 676.80 ± 179.093 |
| h*µg/mL | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC : Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Cycle 1 | 117690.00 ± 18.441 | 97082.85 ± 15.161 | 94324.36 ± 29.059 | 88697.14 ± 20.943 |
| Cycle 2 | 125483.07 ± 17.816 | 111950.59 ± 21.040 | 97712.85 ± 32.246 | 102143.30 ± 17.718 |
| µg/mL | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Cycle 1 | 722.61 ± 11.138 | 663.74 ± 15.158 | 585.92 ± 33.817 | 589.21 ± 15.397 |
| Cycle 2 | 751.13 ± 16.676 | 732.74 ± 21.228 | 573.99 ± 30.092 | 589.53 ± 11.886 |
| Hours | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30g/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Cycle 1 | 2.62 (2.2 to 6.0) | 5.45 (2.4 to 6.0) | 4.50 (2.8 to 6.0) | 5.03 (2.1 to 7.4) |
| Cycle 2 | 2.33 (2.1 to 4.3) | 2.48 (2.3 to 2.8) | 2.51 (2.1 to 2.6) | 2.56 (2.1 to 5.2) |
| Hours | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Terminal Elimination Half-life (t1/2) of Zanidatamab | 242.22 ± 25.482 | 195.53 ± 43.104 | 194.12 ± 21.650 | 240.15 ± 26.357 |
| mL/h | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Apparent Clearance After Oral Administration (CL/F) of Zanidatamab | 12.21 ± 17.713 | 15.35 ± 21.015 | 16.82 ± 20.964 | 16.65 ± 29.235 |
| Participants | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Number of Participants With Anti-zanidatamab Antibodies | 0 | 0 | 1 | 1 |
| Participants | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC : Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| Treatment-emergent adverse event | 3 | 7 | 4 | 4 |
| Serious Adverse event | 0 | 2 | 3 | 2 |
Collected over From the first dose of study drug(s) to 30 days after the last dose or initiation of subsequent anticancer therapy, whichever occured first. Immune-mediated AEs (serious or non-serious) were reported until 90 days after the last dose of tislelizumab, regardless of whether a subsequent anticancer therapy was initiated. Maximum duration of treatment was 51 months.. Non-serious events are listed at a 3% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | 2/11 (18.2%) | 2/11 (18.2%) | 11/11 (100%) |
| Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | 3/27 (11.1%) | 10/27 (37%) | 27/27 (100%) |
| Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | 11/19 (57.9%) | 12/19 (63.2%) | 19/19 (100%) |
| Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX | 5/14 (35.7%) | 5/14 (35.7%) | 14/14 (100%) |
| Event | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| DiarrhoeaGastrointestinal disorders | 1/11 | 0/27 | 2/19 | 1/14 |
| Obstruction gastricGastrointestinal disorders | 0/11 | 0/27 | 2/19 | 0/14 |
| COVID-19Infections and infestations | 0/11 | 0/27 | 2/19 | 1/14 |
| Febrile neutropeniaBlood and lymphatic system disorders | 1/11 | 0/27 | 0/19 | 0/14 |
| CholangitisHepatobiliary disorders | 1/11 | 0/27 | 0/19 | 0/14 |
| CellulitisInfections and infestations | 1/11 | 0/27 | 0/19 | 0/14 |
| VomitingGastrointestinal disorders | 0/11 | 2/27 | 0/19 | 0/14 |
| Blood bilirubin increasedInvestigations | 0/11 | 2/27 | 0/19 | 0/14 |
| Immune-mediated hepatitisHepatobiliary disorders | 0/11 | 0/27 | 0/19 | 1/14 |
| Hip fractureInjury, poisoning and procedural complications | 0/11 | 0/27 | 0/19 | 1/14 |
| Event | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC: Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX |
|---|---|---|---|---|
| DiarrhoeaGastrointestinal disorders | 7/11 | 14/27 | 19/19 | 13/14 |
| AnaemiaBlood and lymphatic system disorders | 1/11 | 22/27 | 3/19 | 5/14 |
| Neutrophil count decreasedInvestigations | 8/11 | 15/27 | 1/19 | 1/14 |
| NauseaGastrointestinal disorders | 5/11 | 6/27 | 12/19 | 10/14 |
| White blood cell count decreasedInvestigations | 0/11 | 17/27 | 1/19 | 1/14 |
| PyrexiaGeneral disorders | 0/11 | 3/27 | 8/19 | 8/14 |
| Decreased appetiteMetabolism and nutrition disorders | 2/11 | 6/27 | 10/19 | 6/14 |
| AlopeciaSkin and subcutaneous tissue disorders | 3/11 | 13/27 | 0/19 | 0/14 |
| VomitingGastrointestinal disorders | 0/11 | 4/27 | 9/19 | 6/14 |
| HypokalaemiaMetabolism and nutrition disorders | 0/11 | 11/27 | 9/19 | 5/14 |
| Age, Continuous(years) | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC : Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX | Total |
|---|---|---|---|---|---|
| Mean | 59.2 ± 10.78 | 53.7 ± 7.87 | 63.3 ± 11.44 | 59.8 ± 8.15 | 58.3 ± 10.05 |
| Sex: Female, Male(Participants) | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC : Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX | Total |
|---|---|---|---|---|---|
| Female | 11 | 27 | 2 | 2 | 42 |
| Male | 0 | 0 | 17 | 12 | 29 |
| Ethnicity (NIH/OMB)(Participants) | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC : Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX | Total |
|---|---|---|---|---|---|
| Hispanic or Latino | 0 | 0 | 0 | 0 | 0 |
| Not Hispanic or Latino | 11 | 27 | 19 | 14 | 71 |
| Unknown or Not Reported | 0 | 0 | 0 | 0 | 0 |
| Race/Ethnicity, Customized(Participants) | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC : Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX | Total |
|---|---|---|---|---|---|
| Asian | 11 | 27 | 19 | 14 | 71 |
| Eastern Cooperative Oncology Group (ECOG) Performance Status(Participants) | Cohort 1A: Breast Cancer: Zanidatamab 30 mg/kg + Docetaxel | Cohort 1B: Breast Cancer: Zanidatamab 1800 mg + Docetaxel | Cohort 2A: Gastric/GEJC: Zanidatamab 30 mg/kg + Tislelizumab + CAPOX | Cohort 2B: Gastric/GEJC : Zanidatamab 1800/2400 mg + Tislelizumab + CAPOX | Total |
|---|---|---|---|---|---|
| Grade 0 | 5 | 6 | 5 | 6 | 22 |
| Grade 1 | 6 | 21 | 14 | 8 | 49 |
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Studies of the drug tested here: Tislelizumab