A Phase 1/2 interventional study of Zalifrelimab and Balstilimab in Cervical Cancer, sponsored by Agenus Inc.. Completed at 47 sites in 9 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-11.
Sponsored by Agenus Inc. · Phase 1/2, Interventional, and Treatment
This is a Phase 1/2, open-label study of zalifrelimab (AGEN1884) in combination with balstilimab (AGEN2034) in participants with locally advanced, recurrent and/or metastatic solid tumors including cervical cancer. Balstilimab is a novel, fully human monoclonal immunoglobulin G4 antibody, designed to block program cell death-1 (PD-1). Zalifrelimab is a novel, fully human monoclonal immunoglobulin G1 antibody, designed to block cytotoxic T-lymphocyte antigen-4 (CTLA-4).
The trial consists of 2 phases:
Phase 1: Dose Escalation:
The enrollment to the Phase 1 portion of the study is completed. The trial will consist of a 3+3 dose escalation that will evaluate different combination dose levels (CDL) of zalifrelimab and balstilimab in participants with locally advanced, recurrent and/or metastatic solid tumors.
Participants may be enrolled to the following CDL cohorts:
CDL1 will be the first to be tested. Dose escalation will continue until the maximum planned CDL (CDL2) is shown to be safe or the maximum tolerated dose (MTD) is reached. The MTD is defined as the CDL below which ≥33% of participants develop dose-limiting toxicities (DLT). The decision to escalate to the next cohort will be made by a safety monitoring committee (SMC), based on safety assessments after all participants of a cohort reached the end of the DLT observation period of 21 days. Should ≥2 DLTs be observed in CDL1, the SMC may open enrollment to CDL-1. The SMC will also select the CDL for Phase 2.
Each participant will receive the combination treatment for a maximum of 24 months or until confirmed disease progression, unacceptable toxicity, or any criterion for withdrawal from the trial or the investigational medicinal products occur. Participants who do not complete the DLT observation period of 21 days after the first dose, for reasons other than a DLT will be replaced. Additional participants will be backfilled, concurrently with the 3+3 dose escalation schema at the lower cleared CDL, to ensure that each cohort enrolls at least 10 participants. These additional participants at each dose level will have the purpose of generating additional safety, pharmacokinetics, and receptor occupancy data, and will not undergo formal DLT observation.
The SMC selected CDL2 (zalifrelimab 1 mg/kg every 6 weeks + balstilimab 3 mg/kg every 2 weeks) as the recommended phase 2 dose (RP2D).
Phase 2: Expansion in Select Tumors
To further characterize safety and efficacy, the following expansion cohort will be enrolled:
Advanced cervical cancer In Phase 2, the RP2D of balstilimab and zalifrelimab will be administered for a maximum of 2 years or until confirmed progression, unacceptable toxicity, or any criterion for stopping the study drugs or withdrawal from the trial occurs.
For the Phase 2 portion of the trial, an independent data monitoring committee will be established to evaluate safety and efficacy and an independent endpoint review committee will be established to adjudicate tumor response.
2,366 studies on the registry are indexed under Uterine Cervical Neoplasms; 677 are open to participants now.
This study's enrollment of 175 is above the median of 100 across 1,738 interventional studies indexed under Uterine Cervical Neoplasms.
Browse Uterine Cervical Neoplasms 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.
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.
To be eligible for participation in this trial the participant must:
Diagnosis:
I. Female having (1) a histologically or cytologically confirmed diagnosis of squamous cell carcinoma, adenosquamous carcinoma, or adenocarcinoma of the cervix, and (2) locally advanced, recurrent, and/or metastatic disease at the time of enrollment. Histologic confirmation of the original primary tumor is required via pathology report. Note: The following cervical tumors are not eligible: minimal deviation/adenoma malignum, gastric type adenocarcinoma, clear cell carcinoma, and mesonephric carcinoma.
II. Has cervical cancer and has after a platinum-based treatment () regimen for locally advanced, recurrent, and/or metastatic disease. Note: Participants who only received platinum-based chemotherapy concurrently with primary radiation (for example, weekly cisplatin) or chemotherapy following completion of radiation therapy (for example, paclitaxel and carboplatin for ≤4 cycles) and progressed within 6 months after treatment completion will be eligible as this systemic therapy will be considered first line.
:
Have adequate organ function as indicated by the following laboratory values:
Female participants must have a negative serum pregnancy test at screening (within 72 hours of first dose of study drug) if of or be of non-childbearing potential. Non-childbearing potential is defined as (by other than medical reasons):
Exclusion Criteria
The participant must be excluded from participating in the trial if the participant:
Has an inadequate prior to first dose of study drug defined as:
Has received prior therapy with:
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.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
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.
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.
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 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.
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.
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.
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 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.
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.
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.
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.
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.
Relapsed and refractory
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Participants received zalifrelimab (1 mg/kg every 6 weeks \[Q6W\]) in combination with balstilimab (1 mg/kg every 2 weeks \[Q2W\]).
Drug: Zalifrelimab · Drug: Balstilimab
Participants received zalifrelimab (1 mg/kg Q6W) in combination with balstilimab (3 mg/kg Q2W).
Drug: Zalifrelimab · Drug: Balstilimab
Participants received the RP2D of zalifrelimab (1 mg/kg Q6W) in combination with balstilimab (3 mg/kg Q2W).
Drug: Zalifrelimab · Drug: Balstilimab
Zalifrelimab was administered over 30 minutes and following the infusion of balstilimab.
Also known as: AGEN1884
Balstilimab infusion was administered over 30 minutes.
Also known as: AGEN2034
Phase 2: Objective Response Rate (ORR) - Independent Endpoint Review Committee (IERC)
The ORR was defined as the percentage of participants with a confirmed best overall response (BOR) of partial response (PR) or complete response (CR), as determined by an IERC per Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1).
Time frame: Up to 2 years
Phase 1: Number of Participants Experiencing Dose-limiting Toxicities (DLTs)
The number of participants with an occurrence of a DLT during dose escalation during the first 21 days of treatment in Phase 1 are reported. Any DLT immediately led to permanent withdrawal of zalifrelimab and balstilimab.
Time frame: First 21 days of treatment
Phase 1: Maximum Drug Concentration Observed Postdose at Steady-state (Cmax-ss) of Balstilimab and Zalifrelimab
Blood samples were collected for serum balstilimab and zalifrelimab concentration analyses. Each cycle was 6 weeks (42 days) long. Results are reported as micrograms/milliliter (ug/mL).
Time frame: Pre-dose, up to 4 hours post-dose (Day 1 of Cycle 2 and Cycle 3)
Phase 2: Cmax-ss of Balstilimab and Zalifrelimab
Blood samples were collected for serum balstilimab and zalifrelimab concentration analyses. Each cycle was 6 weeks (42 days) long.
Time frame: Pre-dose, up to 4 hours post-dose (Day 1 of Cycle 4)
Phase 1: Area Under the Drug Concentration-time Curve From Day 0 to Day 14 at Steady-state (AUC0-14d-ss) of Balstilimab and Zalifrelimab
Blood samples were collected for serum balstilimab and zalifrelimab concentration analyses. Each cycle was 6 weeks (42 days) long. Results are reported as day times ug/mL (day\*ug/mL).
Time frame: Day 1 through Day 15 (Cycle 2 and Cycle 3)
Phase 2: AUC0-14d-ss of Balstilimab and Zalifrelimab
Blood samples were collected for serum balstilimab and zalifrelimab concentration analyses. Each cycle was 6 weeks (42 days) long.
Time frame: Day 1 through Day 15 (Cycle 4)
Phase 1/2: Number of Participants With Serum Anti-drug Antibodies (ADAs) for Balstilimab and Zalifrelimab
Blood samples were collected for serum balstilimab and zalifrelimab ADA determination.
Time frame: Pre-dose through Month 27
Phase 2: ORR - Investigator
The ORR was defined as the percentage of participants with a confirmed BOR of PR or CR, as determined by the investigator per RECIST 1.1.
Time frame: Up to 2 years
Phase 2: Duration of Response (DOR)
DOR was defined as time from first observation of response to first observation of documented disease progression (or death within 12 weeks after last tumor assessment), as determined by an IERC and investigator, per RECIST 1.1. Participants without an event at the analysis cutoff date were censored on date of last tumor assessment. DOR data are reported as 25th percentile estimated from Kaplan-Meier curve.
Time frame: Up to 3 years
Phase 2: Disease Control Rate (DCR)
DCR was defined as the percentage of participants with CR, PR, or stable disease (SD) without progressive disease (PD) within 81 days of study start, or durable SD following PD, as determined by an IERC and investigator, per RECIST 1.1.
Time frame: Up to 3 years
Phase 2: Time to Response (TTR)
TTR was defined as the time interval between the date of treatment initiation and the earliest date of first documented confirmed complete response or partial response based on independent radiologic review, as determined by an IERC per RECIST 1.1.
Time frame: Up to 2 years
Phase 2: Progression-free Survival (PFS)
PFS was defined as the interval from the date of first dose of investigational agent until the earliest date of PD, as determined by IERC and investigator assessment of objective radiographic disease assessments per RECIST 1.1, or death due to any cause if occurring sooner than progression.
Time frame: Up to 2 years
Phase 2: Overall Survival (OS)
OS was defined as the interval from the date of first dose of investigational agent until the date of death.
Time frame: Up to 2 years
Phase 1: Receptor Occupancy (RO) on Circulating T Cells
A validated flow cytometry-based assay was used to evaluate programmed cell death protein-1 (PD-1) RO on circulating T cells as an indication of target engagement of balstilimab. Blood samples were collected for the assay. Results are reported as a percentage of available drug receptors occupied (%RO) by balstilimab; the higher the percentage, the greater the engagement of balstilimab with the target receptor. Initial testing revealed technical limitations of the sample isolation procedure prior to the PD-1 RO assessment, causing the PD-1 RO assay to inaccurately reflect the actual PD-1 RO status in response to balstilimab/zalifrelimab combination treatment. As a result, further sample collection and subsequent testing was not conducted. Only initial test results are reported. Results reported as mean percentage of receptors occupied based upon data collected on Days 8, 15, 22, and 29 of Cycle 1 and Days 1 and 8 of Cycle 2 (each cycle was 6 weeks/42 days long).
Time frame: Days 8, 15, 22, and 29 (Cycle 1); Days 1 and 8 (Cycle 2)
| Milestone | Phase 1 - Dose 1: Zalifrelimab + Balstilimab | Phase 1 - Dose 2: Zalifrelimab + Balstilimab | Phase 2: Zalifrelimab + Balstilimab |
|---|---|---|---|
| Started | 10 | 10 | 0 |
| Received at least 1 dose of study drug | 10 | 10 | 0 |
| Completed | 2 | 0 | 0 |
| Not completed | 8 | 10 | 0 |
| Withdrew: Adverse event | 2 | 0 | 0 |
| Withdrew: Progressive disease | 6 | 10 | 0 |
| Milestone | Phase 1 - Dose 1: Zalifrelimab + Balstilimab | Phase 1 - Dose 2: Zalifrelimab + Balstilimab | Phase 2: Zalifrelimab + Balstilimab |
|---|---|---|---|
| Started | 0 | 0 | 155 |
| Received at least 1 dose of study drug | 0 | 0 | 155 |
| Completed | 0 | 0 | 36 |
| Not completed | 0 | 0 | 119 |
| Withdrew: Withdrawal by subject | 0 | 0 | 15 |
| Withdrew: Adverse event | 0 | 0 | 2 |
| Withdrew: Death | 0 | 0 | 88 |
| Withdrew: Progressive disease | 0 | 0 | 2 |
| Withdrew: Study terminated by sponsor | 0 | 0 | 5 |
| Withdrew: Lost to follow-up | 0 | 0 | 7 |
The ORR was defined as the percentage of participants with a confirmed best overall response (BOR) of partial response (PR) or complete response (CR), as determined by an IERC per Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1).
| percentage of participants | Phase 2: Zalifrelimab + Balstilimab |
|---|---|
| Phase 2: Objective Response Rate (ORR) - Independent Endpoint Review Committee (IERC) | 26.2 (19.7 to 33.9) |
The number of participants with an occurrence of a DLT during dose escalation during the first 21 days of treatment in Phase 1 are reported. Any DLT immediately led to permanent withdrawal of zalifrelimab and balstilimab.
| Participants | Phase 1 - Dose 1: Zalifrelimab + Balstilimab | Phase 1 - Dose 2: Zalifrelimab + Balstilimab |
|---|---|---|
| Phase 1: Number of Participants Experiencing Dose-limiting Toxicities (DLTs) | 0 | 0 |
Blood samples were collected for serum balstilimab and zalifrelimab concentration analyses. Each cycle was 6 weeks (42 days) long. Results are reported as micrograms/milliliter (ug/mL).
| ug/mL | Phase 1 - Dose 1: Zalifrelimab + Balstilimab | Phase 1 - Dose 2: Zalifrelimab + Balstilimab |
|---|---|---|
| Zalifrelimab (Cycle 3, Day 1) | 28.7 ± 26.6 | 27.3 ± 16.4 |
| Balstilimab (Cycle 2, Day 1) | 23.1 ± 28.7 | 71.4 ± 26.5 |
Blood samples were collected for serum balstilimab and zalifrelimab concentration analyses. Each cycle was 6 weeks (42 days) long.
| ug/mL | Phase 2: Zalifrelimab + Balstilimab |
|---|---|
| Zalifrelimab | 16.45 ± 120.2 |
| Balstilimab | 62.40 ± 26.7 |
Blood samples were collected for serum balstilimab and zalifrelimab concentration analyses. Each cycle was 6 weeks (42 days) long. Results are reported as day times ug/mL (day\*ug/mL).
| day*ug/mL | Phase 1 - Dose 1: Zalifrelimab + Balstilimab | Phase 1 - Dose 2: Zalifrelimab + Balstilimab |
|---|---|---|
| Zalifrelimab (Cycle 3) | 213 ± 29.4 | 185 ± 13.2 |
| Balstilimab (Cycle 2) | 74.8 ± 37.4 | 245 ± 28.9 |
Blood samples were collected for serum balstilimab and zalifrelimab concentration analyses. Each cycle was 6 weeks (42 days) long.
| day*ug/mL | Phase 2: Zalifrelimab + Balstilimab |
|---|---|
| Zalifrelimab | 131.1 ± 119.5 |
| Balstilimab | 250.9 ± 119.5 |
Blood samples were collected for serum balstilimab and zalifrelimab ADA determination.
| Participants | Phase 1 - Dose 1: Zalifrelimab + Balstilimab | Phase 1 - Dose 2: Zalifrelimab + Balstilimab | Phase 2: Zalifrelimab + Balstilimab |
|---|---|---|---|
| Zalifrelimab | 0 | 0 | 4 |
| Balstilimab | 1 | 0 | 9 |
The ORR was defined as the percentage of participants with a confirmed BOR of PR or CR, as determined by the investigator per RECIST 1.1.
| percentage of participants | Phase 2: Zalifrelimab + Balstilimab |
|---|---|
| Phase 2: ORR - Investigator | 23.4 (17.3 to 31.0) |
DOR was defined as time from first observation of response to first observation of documented disease progression (or death within 12 weeks after last tumor assessment), as determined by an IERC and investigator, per RECIST 1.1. Participants without an event at the analysis cutoff date were censored on date of last tumor assessment. DOR data are reported as 25th percentile estimated from Kaplan-Meier curve.
| month | Phase 2: Zalifrelimab + Balstilimab |
|---|---|
| IERC | 9.7 (5.6 to NA) |
| Investigator | 8.5 (6.9 to 18.1) |
DCR was defined as the percentage of participants with CR, PR, or stable disease (SD) without progressive disease (PD) within 81 days of study start, or durable SD following PD, as determined by an IERC and investigator, per RECIST 1.1.
| percentage of participants | Phase 2: Zalifrelimab + Balstilimab |
|---|---|
| IERC | 51.7 (43.7 to 59.7) |
| Investigator | 58.6 (50.5 to 66.3) |
TTR was defined as the time interval between the date of treatment initiation and the earliest date of first documented confirmed complete response or partial response based on independent radiologic review, as determined by an IERC per RECIST 1.1.
| day | Phase 2: Zalifrelimab + Balstilimab |
|---|---|
| Phase 2: Time to Response (TTR) | 79.5 (66.5 to 123.5) |
PFS was defined as the interval from the date of first dose of investigational agent until the earliest date of PD, as determined by IERC and investigator assessment of objective radiographic disease assessments per RECIST 1.1, or death due to any cause if occurring sooner than progression.
| month | Phase 2: Zalifrelimab + Balstilimab |
|---|---|
| IERC | 2.7 (1.5 to 3.7) |
| Investigator | 3.0 (2.7 to 5.4) |
OS was defined as the interval from the date of first dose of investigational agent until the date of death.
| month | Phase 2: Zalifrelimab + Balstilimab |
|---|---|
| Phase 2: Overall Survival (OS) | 13.0 (9.7 to 18.5) |
A validated flow cytometry-based assay was used to evaluate programmed cell death protein-1 (PD-1) RO on circulating T cells as an indication of target engagement of balstilimab. Blood samples were collected for the assay. Results are reported as a percentage of available drug receptors occupied (%RO) by balstilimab; the higher the percentage, the greater the engagement of balstilimab with the target receptor. Initial testing revealed technical limitations of the sample isolation procedure prior to the PD-1 RO assessment, causing the PD-1 RO assay to inaccurately reflect the actual PD-1 RO status in response to balstilimab/zalifrelimab combination treatment. As a result, further sample collection and subsequent testing was not conducted. Only initial test results are reported. Results reported as mean percentage of receptors occupied based upon data collected on Days 8, 15, 22, and 29 of Cycle 1 and Days 1 and 8 of Cycle 2 (each cycle was 6 weeks/42 days long).
| percentage of receptors occupied | Phase 1 - Dose 1: Zalifrelimab + Balstilimab |
|---|---|
| Phase 1: Receptor Occupancy (RO) on Circulating T Cells | 30.9 (26.7 to 35.1) |
Collected over From baseline (Day 1) to the end of the study (36 months). Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Phase 1 - Dose 1: Zalifrelimab + Balstilimab | 1/10 (10%) | 6/10 (60%) | 10/10 (100%) |
| Phase 1 - Dose 2: Zalifrelimab + Balstilimab | 1/10 (10%) | 2/10 (20%) | 9/10 (90%) |
| Phase 2: Zalifrelimab + Balstilimab | 88/155 (56.8%) | 68/155 (43.9%) | 145/155 (93.5%) |
| Event | Phase 1 - Dose 1: Zalifrelimab + Balstilimab | Phase 1 - Dose 2: Zalifrelimab + Balstilimab | Phase 2: Zalifrelimab + Balstilimab |
|---|---|---|---|
| ColitisGastrointestinal disorders | 2/10 | 0/10 | 0/155 |
| GastroenteritisInfections and infestations | 1/10 | 0/10 | 0/155 |
| Pelvic infectionInfections and infestations | 1/10 | 0/10 | 1/155 |
| PneumoniaInfections and infestations | 0/10 | 1/10 | 4/155 |
| DuodenitisGastrointestinal disorders | 1/10 | 0/10 | 0/155 |
| PneumonitisRespiratory, thoracic and mediastinal disorders | 0/10 | 1/10 | 3/155 |
| Pulmonary embolismRespiratory, thoracic and mediastinal disorders | 0/10 | 1/10 | 0/155 |
| Cancer painNeoplasms benign, malignant and unspecified (incl cysts and polyps) | 1/10 | 0/10 | 0/155 |
| MigraineNervous system disorders | 1/10 | 0/10 | 0/155 |
| HypotensionVascular disorders | 1/10 | 0/10 | 0/155 |
| Event | Phase 1 - Dose 1: Zalifrelimab + Balstilimab | Phase 1 - Dose 2: Zalifrelimab + Balstilimab | Phase 2: Zalifrelimab + Balstilimab |
|---|---|---|---|
| FatigueGeneral disorders | 6/10 | 5/10 | 30/155 |
| NauseaGastrointestinal disorders | 5/10 | 6/10 | 32/155 |
| Back painMusculoskeletal and connective tissue disorders | 5/10 | 1/10 | 16/155 |
| AnaemiaBlood and lymphatic system disorders | 1/10 | 5/10 | 43/155 |
| DiarrhoeaGastrointestinal disorders | 4/10 | 3/10 | 38/155 |
| Abdominal painGastrointestinal disorders | 4/10 | 0/10 | 19/155 |
| PruritusSkin and subcutaneous tissue disorders | 2/10 | 4/10 | 12/155 |
| ChillsGeneral disorders | 3/10 | 2/10 | 2/155 |
| Influenza like illnessGeneral disorders | 3/10 | 0/10 | 2/155 |
| VomitingGastrointestinal disorders | 3/10 | 3/10 | 30/155 |
Safety Analysis Set: all participants who received ≥1 dose of any study treatment.
| Age, Customized(Participants) | Phase 1 - Dose 1: Zalifrelimab + Balstilimab | Phase 1 - Dose 2: Zalifrelimab + Balstilimab | Phase 2: Zalifrelimab + Balstilimab | Total |
|---|---|---|---|---|
| Adults (18-64 years) | 7 | 8 | 140 | 155 |
| From 65-84 years | 3 | 2 | 15 | 20 |
| Sex: Female, Male(Participants) | Phase 1 - Dose 1: Zalifrelimab + Balstilimab | Phase 1 - Dose 2: Zalifrelimab + Balstilimab | Phase 2: Zalifrelimab + Balstilimab | Total |
|---|---|---|---|---|
| Female | 8 | 7 | 155 | 170 |
| Male | 2 | 3 | 0 | 5 |
| Ethnicity (NIH/OMB)(Participants) | Phase 1 - Dose 1: Zalifrelimab + Balstilimab | Phase 1 - Dose 2: Zalifrelimab + Balstilimab | Phase 2: Zalifrelimab + Balstilimab | Total |
|---|---|---|---|---|
| Hispanic or Latino | 0 | 0 | 9 | 9 |
| Not Hispanic or Latino | 10 | 10 | 143 | 163 |
| Unknown or Not Reported | 0 | 0 | 3 | 3 |
| Race/Ethnicity, Customized(Participants) | Phase 1 - Dose 1: Zalifrelimab + Balstilimab | Phase 1 - Dose 2: Zalifrelimab + Balstilimab | Phase 2: Zalifrelimab + Balstilimab | Total |
|---|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 1 | 1 |
| Asian (Chinese) | 0 | 0 | 1 | 1 |
| Black or African American | 0 | 0 | 1 | 1 |
| White | 10 | 10 | 148 | 168 |
| South African | 0 | 0 | 1 | 1 |
| Indigenous and Torres Strait Islander | 0 | 0 | 1 | 1 |
| Australian Aboriginal | 0 | 0 | 1 | 1 |
| Unknown | 0 | 0 | 1 | 1 |
PDFs hosted by the registry, ClinicalTrials.gov.
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Studies of the drugs tested here: Zalifrelimab · Balstilimab