A Phase 1 interventional study of Botensilimab and Balstilimab in Advanced Cancer, Angiosarcoma and Colorectal Cancer Without Liver Metastases, sponsored by Agenus Inc.. Active, not recruiting at 18 sites in 2 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-03-30.
Sponsored by Agenus Inc. · Phase 1, Interventional, and Treatment
This study is an open-label, Phase 1, multicenter study to evaluate the safety, tolerability, pharmacokinetics (PK), and pharmacodynamic (PD) profiles of a novel fragment crystallizable (Fc)-engineered immunoglobulin G1 anti-cytotoxic T-lymphocyte antigen 4 (anti-CTLA-4) human monoclonal antibody (botensilimab) monotherapy and in combination with an anti-programmed cell death protein-1 (PD-1) antibody (balstilimab), and to assess the maximum tolerated dose (MTD) in participants with advanced solid tumors. This study will also determine the recommended phase 2 dose (RP2D) of botensilimab monotherapy and in combination with balstilimab.
This Phase 1 study will enroll up to approximately 550 evaluable adult participants with refractory, advanced cancer (solid tumors).
The study will consist of a 3+3 dose escalation. Different dose levels of botensilimab, both monotherapy and in combination with balstilimab, will be evaluated in individual cohorts based upon dose. Each participant will remain in the cohort of the dose level and schedule assigned at study entry. Participants can be replaced for any reason other than a dose-limiting toxicity (DLT). Participants will receive treatment for ≤ 2 years or until progressive disease, unacceptable toxicity, or any criterion for stopping the study drug or withdrawal of trial occurs.
Additionally, the study is intended to further explore the safety, PK, PD, and clinical activity in selected cancer types at dose levels (botensilimab monotherapy and combination therapy with balstilimab) determined as potentially effective. Indications of interest include, but are not limited to, non-small-cell lung cancer, melanoma, endometrial cancer, ovarian cancer, angiosarcoma, colorectal cancer without liver metastases, prostate cancer, and fibrolamellar carcinoma.
99 studies on the registry are indexed under Hemangiosarcoma; 16 are open to participants now.
This study's enrollment of 499 is above the median of 64 across 83 interventional studies indexed under Hemangiosarcoma.
Browse Hemangiosarcoma studies →Agenus Inc. is the lead sponsor of 31 studies on the registry; 2 are open to participants now.
Of its 11 completed or terminated interventional studies of FDA-regulated products, 3 (27%) have results posted.
Counted across the registry records on this site, refreshed daily.
Inclusion Criteria:
For inclusion in the trial, all of the following inclusion criteria must be fulfilled, as no waivers will be permitted:
Adequate organ and bone marrow reserve function, as indicated by the following laboratory values:
Female participants of must have a negative serum pregnancy test at screening (within 72 hours of first dose of study medication). Non-childbearing potential is defined as 1 of the following:
Female participants of childbearing potential must be willing to use highly effective measures starting with the Screening visit through 90 days after last dose of study treatment. For the UK only, highly effective contraceptive measures are defined as follows:
Combined (estrogen and progesterone containing) hormonal contraception associated with inhibition of ovulation.
Progesterone-only hormonal contraception associated with inhibition of ovulation.
Male participants with a female partner(s) of childbearing potential must agree to use highly effective contraceptive measures throughout the trial starting with the Screening visit through 90 days after the last dose of study treatment is received. Males with pregnant partners must agree to use a condom (which is not considered "highly effective"); no additional method of contraception is required for the pregnant partner. Note: Abstinence is acceptable if this is the established and preferred contraception method for the participant.
The following inclusion criteria are in addition to the above criteria. If there are criteria below that differs from above, the below indication-specific criteria take precedence.
Additional Inclusion Criteria for Angiosarcoma Cohort
Histologically or cytologically confirmed diagnosis of metastatic or locally advanced angiosarcoma for which no standard therapy is available or standard therapy has failed.
Additional Inclusion Criteria for the Hepatocellular Cancer (HCC) Cohort
Adequate organ and bone marrow reserve function as indicated by the following laboratory values:
Participants are eligible to enroll if they have non-viral-HCC or if they have (HBV), or virus (HCV) related HCC, defined as follows:
Additional Inclusion Criteria for the Non-Small Cell Lung Cancer (NSCLC) Cohort
Histologically or cytologically confirmed diagnosis of metastatic or locally advanced NSCLC for which no standard therapy is available or standard therapy has failed:
Additional Inclusion Criteria for the Prostate Cancer Cohort
Must have demonstrated serologic or radiographic progression on or following the most recent therapy in the setting of castrate-level testosterone (\< 50 nanograms per mL [ng/mL] and/or maintained on medical/surgical castration throughout) as defined by at least one of the following:
Must maintain castration status defined as serum testosterone \< 50 ng/mL. Must be either surgically castrate or on luteinizing hormone-releasing hormone analog for the duration of the study.
Additional Inclusion Criteria for Breast Cancer
Exclusion Criteria:
For inclusion in the trial, participant must meet none of the following exclusion criteria, as no waivers will be permitted:
History of:
Concurrent requiring treatment or history of prior malignancy active within 2 years prior to the first dose of study treatment. Exceptions: participants with completely resected prior early-stage basal/squamous cell skin cancer or treated cervical carcinoma in situ.
The following exclusion criteria are in addition to the above criteria. If there are criteria below that differs from above, the below indication-specific criteria take precedence.
Additional Exclusion Criteria for the HCC Cohort
Ascites requiring paracentesis within the last 3 months. Participants with previous ascites that is managed with stable doses of diuretics and have a Child Pugh score of A are allowed.
Exclusion Criterion Specific for the UK
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.
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.
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 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.
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 number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
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.
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.
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
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.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.
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.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
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 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.
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.
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 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.
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.
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.
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.
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.
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 human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
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.
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.
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.
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.
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.
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.
Absolute neutrophil count (ANC)
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
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.
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.
INR, PT and aPTT (clotting tests)
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
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.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Postmenopausal
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Child-Pugh class
A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.
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.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
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.
3+3 Dose escalation: botensilimab, every 3 weeks, starting at dose level 0.1 milligrams/kilogram (mg/kg) up to 4 mg/kg, administered intravenously (IV) for up to 2 years.
Drug: Botensilimab
3+3 Dose escalation: botensilimab, every 6 weeks, starting at dose level 1 mg/kg up to 4 mg/kg, administered IV for up to 2 years.
Drug: Botensilimab
3+3 Dose escalation: balstilimab, every 2 weeks, at dose level 3 mg/kg in combination with botensilimab, every 6 weeks, starting at dose level 0.1 mg/kg up to 4 mg/kg, administered IV for up to 2 years. Participants enrolled at sites in the United Kingdom (UK) may have the option for extended treatment. An additional cohort will investigate balstilimab, every 3 weeks, at 450 mg in combination with botensilimab every 6 weeks, at 150 mg, administered IV for up to 2 years.
Drug: Botensilimab · Drug: Balstilimab
An Fc-engineered anti-CTLA-4 monoclonal antibody
Also known as: AGEN1181, Anti-CTLA-4
A fully human monoclonal anti-PD-1 antibody
Also known as: AGEN2034, Anti-PD-1
Incidence Of Treatment-emergent Adverse Events (TEAEs)
TEAEs will include adverse events of special interest, immune-related adverse events, and adverse drug reactions, according to National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) Version 5.0.
Time frame: First dose through 90 days following last study dose (up to 2 years)
DLT Of Botensilimab
DLTs will include any Grade 2 or greater drug related toxicity for all dose groups, according to NCI CTCAE version 5.0 and protocol specifications.
Time frame: First 28 days of treatment
RP2D Of Botensilimab
MTD based on DLT occurrence at DLT period (28 days after first dose) and all TEAEs seen through 90 days following last study dose.
Time frame: First dose through 90 days following last study dose
Objective Response Rate (ORR) According To Response Evaluation Criteria In Solid Tumors Version 1.1 (RECIST 1.1)
Confirmed ORR will be in the analysis population.
Time frame: First dose through up to 2 years
ORR According to Prostate Cancer Working Group 3 (PCWG3)
Confirmed ORR will be in the analysis population.
Time frame: First dose through up to 2 years
Duration Of Response (DOR) According To RECIST 1.1
Time frame: From first dose to first observation of documented disease progression (or death within 12 weeks of last tumor assessment) (up to 2 years)
DOR According to PCWG3
Time frame: From first dose to first observation of documented disease progression (or death within 12 weeks of last tumor assessment) (up to 2 years)
Disease Control Rate (DCR) According To RECIST 1.1
DCR will include complete response, partial response, and stable disease.
Time frame: First study dose through 24 weeks
DCR According to PCWG3
DCR will include complete response, partial response, and stable disease.
Time frame: First study dose through 24 weeks
Progression-free Survival (PFS) According To RECIST 1.1
PFS time will be assessed.
Time frame: First study dose to first observation of documented disease progression (or death within 12 weeks of last tumor assessment) (up to 2 years)
PFS According to PCWG3
PFS time will be assessed.
Time frame: First study dose to first observation of documented disease progression (or death within 12 weeks of last tumor assessment) (up to 2 years)
Overall Survival Time
Duration of survival will be assessed.
Time frame: First study dose through up to 3 years
Maximum Drug Concentration At Steady-state (Cmax-ss)
Serum botensilimab concentrations measured throughout the study
Time frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years)
Minimum Drug Concentration At Steady-state (Cmin-ss)
Serum botensilimab concentration measured throughout the study
Time frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years)
Area Under The Drug Concentration-time Curve Within Time Span t1 To t2 At Steady-state (AUC(t1-t2)-ss)
Serum botensilimab concentrations measured throughout the study
Time frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years)
Area Under The Drug Concentration-time Curve From Time Zero To Infinity [AUC(0-∞)]
Serum botensilimab concentrations measured throughout the study
Time frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years)
Terminal Elimination Rate Constant (λz)
Serum botensilimab concentrations measured throughout the study
Time frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years)
Terminal Elimination Half-life (t1/2)
Serum botensilimab concentrations measured throughout the study
Time frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years)
Systemic Clearance (CL)
Serum botensilimab concentrations measured throughout the study
Time frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years)
Volume Of Distribution (Vd)
Serum botensilimab concentrations measured throughout the study
Time frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years)
Anti-drug Antibodies (ADAs)
Serum botensilimab ADAs measured throughout the study
Time frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years)
Plan to share: No
Ran from Mar 2019 to primary completion in Jan 2025, 69 months.
How these figures are worked out, and which studies are left out of them.
This study is active, not recruiting, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Botensilimab