A Phase 2 interventional study of Evorpacept (ALX148) and Trastuzumab in Breast Cancer, Metastatic, sponsored by ALX Oncology Inc.. Recruiting at 61 sites in 8 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-09.
Sponsored by ALX Oncology Inc. · Phase 2, Interventional, and Treatment
The Substudy Protocol ASPEN-09-03 is a Phase 2, single-arm, multicenter study evaluating the efficacy, safety, and tolerability of evorpacept in combination with trastuzumab and chemotherapy in participants with HER2-positive metastatic breast cancer who have previously received trastuzumab-deruxtecan. This substudy is actively recruiting.
ASPEN-09-03 is a substudy under Master Protocol ASPEN-09, and additional substudies are as follows:
Participants will continue study treatment until disease progression, death, unacceptable toxicity, participant request to stop treatment, investigator decision or study termination by the sponsor.
As ASPEN-09-03 (MBC) is the only substudy open under ASPEN-09, the information reflected in the enrollment number, arms/interventions, outcome measures, and eligibility criteria currently includes only MBC.
14,825 studies on the registry are indexed under Breast Neoplasms; 3,319 are open to participants now.
This study's planned enrollment of 120 is above the median of 72 across 10,896 interventional studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →ALX Oncology Inc. is the lead sponsor of 9 studies on the registry; 2 are open to participants now.
Of its 5 completed or terminated interventional studies of FDA-regulated products, 0 (0%) 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.
Adequate liver function:
Exclusion Criteria:
Following anti-cancer therapy with insufficient before start of treatment:
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 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.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
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.
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 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.
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 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 study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
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.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
The US National Cancer Institute’s scale of how severe an adverse event is — any unwanted medical event during a study, such as a symptom, an illness or an abnormal test result, whether or not a treatment caused it. Whether it did is judged separately.
“Side effects of earlier treatment resolved to grade 1 or less” means they have settled to mild or gone.
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.
The number of CD4 cells, a type of white blood cell, in a given amount of blood. It is used to follow how well the immune system is doing in HIV.
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.
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 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.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Creatinine clearance (CrCl)
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
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.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
CTCAE grade
The US National Cancer Institute’s scale of how severe an adverse event is — any unwanted medical event during a study, such as a symptom, an illness or an abnormal test result, whether or not a treatment caused it. Whether it did is judged separately.
“Side effects of earlier treatment resolved to grade 1 or less” means they have settled to mild or gone.
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.
CD4 count
The number of CD4 cells, a type of white blood cell, in a given amount of blood. It is used to follow how well the immune system is doing in HIV.
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.
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.
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.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
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.
* Evorpacept (IV) - once every 3 weeks (Q3W) * Trastuzumab (IV) - once every 3 weeks (Q3W) * Chemotherapy (physician selects one of the following): * Capecitabine (Oral) twice a day for 14 days every 3 weeks * Eribulin (IV) twice every 3 weeks * Gemcitabine (IV) twice every 3 weeks * Paclitaxel (IV) once every 3 weeks (Q3W) or once weekly (QW) * Vinolrebine (IV) twice every 3 weeks
Drug: Evorpacept (ALX148) · Drug: Trastuzumab · Drug: Paclitaxel · Drug: Capecitabine · Drug: Eribulin · Drug: Gemcitabine · Drug: Vinorelbine
IV infusion
IV infusion
Also known as: Herceptin
IV infusion
Also known as: Taxol
Oral administration
Also known as: Xeloda
IV infusion
Also known as: Halaven
IV infusion
Also known as: Gemzar
IV infusion
Also known as: Navelbine
Overall Response Rate (ORR) using RECIST v1.1 based on BICR assessment
Evaluate the ORR of evorpacept in combination with trastuzumab and single-agent chemotherapy in the sub-population of participants with metastatic HER2-positive breast cancer who express CD47 (CD47+). ORR is defined as a best overall response (BOR) of confirmed complete response (CR) or partial response (PR) using RECIST v1.1 based on BICR assessment.
Time frame: Approximately 6 months after the last participant is enrolled
Overall Response Rate (ORR) based on Investigator assessment
Evaluate the ORR of evorpacept in combination with trastuzumab and single-agent chemotherapy in the sub-population of participants with metastatic HER2-positive breast cancer who express CD47 (CD47+). ORR is defined as a best overall response (BOR) of confirmed complete response (CR) or partial response (PR) based on Investigator Assessment.
Time frame: Approximately 6 months after the last participant is enrolled
Clinical Benefit Rate (CBR) using RECIST v1.1 based on BICR and Investigator assessment
Evaluate the CBR of evorpacept in combination with trastuzumab and single-agent chemotherapy in the sub-population of participants with metastatic HER2-positive breast cancer who express CD47 (CD47+). CBR is defined as the proportion of participants whose BOR is confirmed PR, confirmed CR, or SD with duration \>6 months using RECIST v1.1 based on BICR and Investigator assessment.
Time frame: Approximately 6 months after the last participant is enrolled
Duration of Response (DoR) using RECIST v1.1 based on BICR and Investigator assessment
Evaluate the DoR of evorpacept in combination with trastuzumab and single-agent chemotherapy in the sub-population of participants with metastatic HER2-positive breast cancer who express CD47 (CD47+). DoR is measured from the time measurement criteria are first met for CR / PR (whichever is first recorded) until documented progressive disease or death from any cause, whichever occurs first using RECIST v1.1 based on BICR and Investigator assessment.
Time frame: Approximately 6 months after the last participant is enrolled
Progression-Free Survival (PFS) using RECIST v1.1 based on BICR and Investigator assessment
Evaluate the PFS of evorpacept in combination with trastuzumab and single-agent chemotherapy in the sub-population of participants with metastatic HER2-positive breast cancer who express CD47 (CD47+). PFS is measured from the date of enrollment until documented progressive disease or death from any cause, whichever occurs first, using RECIST v1.1 based on BICR and Investigator assessment
Time frame: Approximately 6 months after the last participant is enrolled
Overall Survival (OS)
Evaluate the OS of evorpacept in combination with trastuzumab and single-agent chemotherapy in the sub-population of participants with metastatic HER2-positive breast cancer who express CD47 (CD47+). OS is defined as the time from the date of enrollment until death.
Time frame: Approximately 6 months after the last participant is enrolled
Number of participants with adverse events (AEs) and with laboratory abnormalities
AEs as characterized by type, frequency, severity (as graded by NCI CTCAE v5.0), timing, seriousness, and relationship to study drug. Laboratory abnormalities as characterized by type, frequency, severity, and timing.
Time frame: Enrollment to 28 days after the last administration of the study drug
Maximum Concentration (Cmax)
To evaluate the Cmax of evorpacept
Time frame: Approximately 6 months after the last participant is enrolled
Time at Maximum Concentration (Tmax)
To evaluate the Tmax of evorpacept
Time frame: Approximately 6 months after the last participant is enrolled
Area under the Concentration-Time Curve (AUC)
To evaluate the AUC of evorpacept
Time frame: Approximately 6 months after the last participant is enrolled
Clearance (CL)
To evaluate the CL of evorpacept
Time frame: Approximately 6 months after the last participant is enrolled
Terminal elimination half-life (t1/2)
To evaluate the t1/2 of evorpacept
Time frame: Approximately 6 months after the last participant is enrolled
Evaluate the immunogenicity of evorpacept
Measured by presence of human serum ADA (anti-evorpacept antibodies)
Time frame: Approximately 6 months after the last participant is enrolled
Not enrolling at this site — choose another above.
Plan to share: No
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 ↗
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Studies of the drug tested here: ALX148
ALX Oncology Inc.