Fc-Engineered Anti-CTLA-4 Monoclonal Antibody in Advanced Cancer
![]() |
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. |
ClinicalTrials.gov Identifier: NCT03860272 |
Recruitment Status :
Recruiting
First Posted : March 1, 2019
Last Update Posted : September 16, 2022
|
- Study Details
- Tabular View
- No Results Posted
- Disclaimer
- How to Read a Study Record
Condition or disease | Intervention/treatment | Phase |
---|---|---|
Advanced Cancer Angiosarcoma Colorectal Cancer Without Liver Metastases Endometrial Cancer Fibrolamellar Carcinoma Melanoma Non-small-cell Lung Cancer Ovarian Cancer | Drug: Botensilimab Drug: Balstilimab | Phase 1 |
This Phase 1 study will enroll up to approximately 195 evaluable adult participants with refractory cancer (solid tumors) regardless of diagnosis.
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, and fibrolamellar carcinoma.
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 195 participants |
Allocation: | Non-Randomized |
Intervention Model: | Single Group Assignment |
Intervention Model Description: | Dose escalation |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | A Phase 1 Study of AGEN1181, an Fc-Engineered Anti-CTLA-4 Monoclonal Antibody as Monotherapy and in Combination With AGEN2034 (Balstilimab), an Anti-PD-1 Monoclonal Antibody, in Subjects With Advanced Cancer |
Actual Study Start Date : | April 1, 2019 |
Estimated Primary Completion Date : | December 2024 |
Estimated Study Completion Date : | December 2024 |

Arm | Intervention/treatment |
---|---|
Experimental: 3-Week Monotherapy
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
An Fc-engineered anti-CTLA-4 monoclonal antibody
Other Names:
|
Experimental: 6-Week Monotherapy
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
An Fc-engineered anti-CTLA-4 monoclonal antibody
Other Names:
|
Experimental: 6-Week Combination Therapy
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. 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
An Fc-engineered anti-CTLA-4 monoclonal antibody
Other Names:
Drug: Balstilimab A fully human monoclonal anti-PD-1 antibody
Other Names:
|
- Incidence Of Treatment-emergent Adverse Events (TEAEs) [ Time Frame: First dose through 90 days following last study dose (up to 2 years) ]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.
- DLT Of Botensilimab [ Time Frame: First 28 days of treatment ]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.
- RP2D Of Botensilimab [ Time Frame: First dose through 90 days following last study dose ]MTD based on DLT occurrence at DLT period (28 days after first dose) and all TEAEs seen 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) [ Time Frame: First dose through up to 2 years ]Confirmed ORR will be in the analysis population.
- 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) ]
- Disease Control Rate (DCR) According To RECIST 1.1 [ Time Frame: First study dose through 24 weeks ]DCR will include complete response, partial response, and stable disease for at least 12 weeks.
- Progression-free Survival (PFS) According To RECIST 1.1 [ 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 time will be assessed.
- Overall Survival Time [ Time Frame: First study dose through up to 3 years ]Duration of survival will be assessed.
- Maximum Drug Concentration At Steady-state (Cmax-ss) [ Time Frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years) ]Serum botensilimab concentrations measured throughout the study
- Minimum Drug Concentration At Steady-state (Cmin-ss) [ Time Frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years) ]Serum botensilimab concentration measured throughout the study
- Area Under The Drug Concentration-time Curve Within Time Span t1 To t2 At Steady-state (AUC(t1-t2)-ss) [ Time Frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years) ]Serum botensilimab concentrations measured throughout the study
- Area Under The Drug Concentration-time Curve From Time Zero To Infinity [AUC(0-∞)] [ Time Frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years) ]Serum botensilimab concentrations measured throughout the study
- Terminal Elimination Rate Constant (λz) [ Time Frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years) ]Serum botensilimab concentrations measured throughout the study
- Terminal Elimination Half-life (t1/2) [ Time Frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years) ]Serum botensilimab concentrations measured throughout the study
- Systemic Clearance (CL) [ Time Frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years) ]Serum botensilimab concentrations measured throughout the study
- Volume Of Distribution (Vd) [ Time Frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years) ]Serum botensilimab concentrations measured throughout the study
- Anti-drug Antibodies (ADAs) [ Time Frame: First study dose (pre-dose) through 3 months following last study dose (up to 2 years) ]Serum botensilimab ADAs measured throughout the study

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
For inclusion in the trial, all of the following inclusion criteria must be fulfilled, as no waivers will be permitted:
- Provision of signed and dated written informed consent prior to any study specific procedures. Participation in pharmacogenomics testing is optional.
- Histologically or cytologically confirmed diagnosis of metastatic or locally advanced solid tumor for which no standard therapy is available or standard therapy has failed.
- Measurable disease on imaging based on RECIST 1.1.
- Life expectancy of ≥ 3 months and Eastern Cooperative Oncology Group performance status of 0 or 1.
-
Adequate organ and bone marrow reserve function, as indicated by the following laboratory values:
- Adequate hematological function, defined as absolute neutrophil count ≥ 1.5 × 10^9/liter (L), platelet count ≥ 100 × 10^9/L, and hemoglobin ≥ 8 grams/deciliter without recent transfusion (defined as a transfusion that has occurred within 2 weeks of the hemoglobin measurement).
- Adequate liver function, defined as total bilirubin level ≤ 1.5 × institutional upper limit of normal (IULN), aspartate aminotransferase ≤ 2.5 × IULN, and alanine aminotransferase ≤ 2.5 × IULN.
- Adequate renal function defined as creatinine ≤ 1.5 × IULN or measured or calculated creatinine clearance ≥ 40 milliliters/minute per institutional standard. Assessment methods should be recorded.
- Adequate coagulation, defined as international normalized ratio or prothrombin time ≤ 1.5 × IULN and activated partial thromboplastin time ≤ 1.5 × IULN (unless participant receiving anticoagulant therapy).
- No history of prior or concomitant malignancy that requires other active treatment.
- Participants must provide a sufficient and adequate formalin-fixed paraffin embedded tumor tissue sample (fresh biopsy) collected within 28 days before the first dose from a site not previously irradiated and agree to a mandatory on-treatment biopsy if clinically feasible.
-
Female participants of childbearing potential 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:
- ≥ 45 years of age and has not had menses for > 1 year.
- Amenorrheic for > 2 years without a hysterectomy and/or oophorectomy and follicle stimulating hormone value in the postmenopausal range upon pretrial (screening) evaluation.
- Status is post-hysterectomy, -oophorectomy, or -tubal ligation.
- Female participants of childbearing potential must be willing to use highly effective contraceptive measures starting with the Screening visit through 90 days after last dose of study treatment. Note: Abstinence is acceptable if this is the established and preferred contraception for the participant.
- 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; 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.
Exclusion Criteria:
For inclusion in the trial, participant must meet none of the following exclusion criteria, as no waivers will be permitted:
- Currently participating and receiving study therapy or has participated in a study of an investigational agent and received study therapy or used an investigation device within 3 weeks of first dose of current study drug.
- Received prior systemic cytotoxic chemotherapy, biological therapy, radiotherapy, or major surgery within 3 weeks prior to first dose of study drug. A 1-week washout is permitted for palliative radiation to non-central nervous system (CNS) disease, with Sponsor approval.
- Participants who have received prior CTLA-4 therapy may be enrolled in selected indications upon agreement with the Sponsor. Note: Selected expansion cohorts may accept prior therapy with anti-CTLA-4 antibody or agent.
- Persistent toxicity of NCI CTCAE version 5.0 Grade > 1 severity that is related to prior therapy. Note: Sensory neuropathy, endocrinopathy requiring hormonal replacement therapy, or alopecia of Grade ≤ 2 are acceptable.
- Expected to require any other form of systemic or localized antineoplastic therapy while on trial (including maintenance therapy with another agent, radiation therapy, and/or surgical resection).
- Known severe (Grade ≥ 3) hypersensitivity reactions to fully human monoclonal antibodies, antibody, or severe reaction to immuno-oncology agents, such as colitis or pneumonitis requiring treatment with steroids; or has a history of interstitial lung disease, any history of anaphylaxis, or uncontrolled asthma.
- Receiving systemic corticosteroid therapy 1 week prior to the first dose of study drug or receiving any other form of systemic immunosuppressive medication. Note: Corticosteroid use as a premedication for IV contrast allergies/reactions is allowed. Participants who are receiving daily corticosteroid replacement therapy are also an exception to this rule. Daily prednisone at doses of ≤ 7.5 mg or equivalent hydrocortisone dose are examples of permitted replacement therapy. Use of inhaled or topical corticosteroids is permitted.
- CNS tumor, metastasis(es), and/or carcinomatous meningitis identified either on the baseline brain imaging obtained during the screening period or identified prior to consent. Note: Participants with history of brain metastases that have been treated may participate provided they show evidence of stable supra-tentorial lesions at screening (defined as 2 brain images, both of which are obtained after treatment to the brain metastases and obtained ≥ 4 weeks apart). Any neurologic symptoms that developed either as a result of the brain metastases or their treatment must have returned to baseline or resolved. Any steroids administered as part of this therapy must be completed ≥3 days prior to first dose of study medication.
- Active or history of autoimmune disease that requires systemic treatment within 2 years of the start of study drug (that is, with use of disease-modifying agents, corticosteroids, or immunosuppressive drugs). Note: Participants with autoimmune conditions requiring hormone replacement therapy or topical treatments are eligible.
- Has had an allogeneic tissue/solid organ transplant, except for corneal transplants.
- Active infection requiring treatment.
- Known history of human immunodeficiency virus type 1 or 2 antibodies.
- Known active infection with hepatitis B and/or hepatitis C virus.
- Clinically significant (that is, active) cardiovascular disease: cerebral vascular accident/stroke or myocardial infarction within 6 months of enrollment, unstable angina, congestive heart failure (New York Heart Association class ≥ II), or serious uncontrolled cardiac arrhythmia requiring medication.
- History or current evidence of any condition, therapy, any active infections, or laboratory abnormality that might confound the results of the trial, interfere with the participant's participation for the full duration of the trial, or is not in the best interest of the participant to participate, in the opinion of the treating Investigator.
- Known psychiatric or substance abuse disorder that would interfere with cooperation with the requirements of the study.
- Legally incapacitated or has limited legal capacity.
- Pregnant or breastfeeding.
- For participants in the colorectal cancer expansion cohort only: current or previous evidence of liver metastases as determined by computed tomography, magnetic resonance imaging, or biopsy.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03860272
Contact: Agenus Inc. Clinical Trial Information | 781-674-4265 | clinicaltrialinfo@Agenusbio.com |
United States, Arizona | |
HonorHealth Research Institute | Recruiting |
Scottsdale, Arizona, United States, 85258 | |
Contact: Clinical Trials Nurse Navigation 480-323-1364 clinicaltrials@honorhealth.com | |
Principal Investigator: Michael Gordon, MD | |
United States, California | |
City of Hope Comprehensive Cancer Center | Recruiting |
Duarte, California, United States, 91010 | |
Contact: Erin Morones emorones@coh.org | |
Principal Investigator: Marwan G Fakih, MD | |
The Angeles Clinic & Research Institute, a Cedars-Sinai Affiliate | Recruiting |
Los Angeles, California, United States, 90025 | |
Contact: Candice Benhamou 310-582-7906 CBenhamou@theangelesclinic.org | |
Principal Investigator: Ani Balmanoukian, MD | |
University of Southern California Norris Comprehensive Cancer Center | Recruiting |
Los Angeles, California, United States, 90033 | |
Contact: Arthur Alvarez 323-409-4365 arthur.alvarez@med.usc.edu | |
Principal Investigator: Anthony El-Khoueiry, MD | |
Saint John's Cancer Institute | Recruiting |
Santa Monica, California, United States, 90404 | |
Contact: Irving Ledesma 310-582-7047 irving.ledesmaprado@providence.org | |
Principal Investigator: Kim Margolin, MD | |
United States, Colorado | |
University of Colorado | Recruiting |
Aurora, Colorado, United States, 80045 | |
Contact: Meghan Ayers 720-848-5278 meghan.ayers@cuanschutz.edu | |
Principal Investigator: Breelyn Wilky, MD | |
United States, Florida | |
University of Miami Sylvester Comprehensive Cancer Center | Recruiting |
Miami, Florida, United States, 33136 | |
Contact: Nailet Real Bestard nxr518@med.miami.edu | |
Principal Investigator: Jonathan Trent, MD | |
United States, Massachusetts | |
Beth Israel Deaconess Medical Center | Recruiting |
Boston, Massachusetts, United States, 02215 | |
Contact: Eileen Kim nkim10@bidmc.harvard.edu | |
Principal Investigator: Andrea Bullock, MD | |
Dana-Farber Cancer Institute | Recruiting |
Boston, Massachusetts, United States, 02215 | |
Contact: Benjamin Schlechter, MD 617-632-3000 benjamin_schlechter@dfci.harvard.edu | |
Principal Investigator: Benjamin Schlechter, MD | |
United States, New York | |
Columbia University Medical Center | Recruiting |
New York, New York, United States, 10032 | |
Contact: Samantha Petruzzelli sp40992@cumc.columbia.edu | |
Principal Investigator: Gary K Schwartz, MD | |
Memorial Sloan Kettering Cancer Center | Recruiting |
New York, New York, United States, 10065 | |
Contact: Amin Yaqubie 212-639-2000 yaqubiea@mskcc.org | |
Contact: Olivia Heffernan 212-639-2000 hefferno@mskcc.org | |
Principal Investigator: Ghassan Khaled Abou-Alfa, MD | |
United States, Ohio | |
Ohio State University | Withdrawn |
Columbus, Ohio, United States, 43210 | |
United States, Oregon | |
Providence Portland Cancer Center | Recruiting |
Portland, Oregon, United States, 97213 | |
Contact: Melissa Ngirailemesang, RN 503-215-2714 CanClinRsrchStudies@providence.org | |
Principal Investigator: Rachel E Sanborn, MD | |
United States, Texas | |
MD Anderson Cancer Center | Recruiting |
Houston, Texas, United States, 77030 | |
Contact: Becky Norris bnorris@mdanderson.org | |
Principal Investigator: Apostolia Tsimberidou, MD, PhD | |
The University of Texas Health Science Center at San Antonio | Recruiting |
San Antonio, Texas, United States, 78229 | |
Contact: Hope Moreno, RN MorenoH@uthscsa.edu | |
Principal Investigator: Mahadevan Daruka, MD |
Study Director: | Medical Director | Agenus Inc. |
Responsible Party: | Agenus Inc. |
ClinicalTrials.gov Identifier: | NCT03860272 |
Other Study ID Numbers: |
C-800-01 |
First Posted: | March 1, 2019 Key Record Dates |
Last Update Posted: | September 16, 2022 |
Last Verified: | September 2022 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Solid Tumors Advanced Cancer Open-label Dose Escalation Monotherapy |
Combination Therapy Anti-CTLA-4 Anti-PD-1 Immunotherapy |
Neoplasms Endometrial Neoplasms Hemangiosarcoma Neoplasms by Site Neoplasms by Histologic Type Genital Neoplasms, Female |
Urogenital Neoplasms Uterine Neoplasms Uterine Diseases Sarcoma Neoplasms, Connective and Soft Tissue Neoplasms, Vascular Tissue |