This study is an open-label, Phase 1/2, multicenter study to evaluate the safety,
tolerability, PK, and PD profiles of a novel Fc-engineered IgG1 anti-CTLA-4 human monoclonal
antibody (AGEN1181) monotherapy and in combination with a human monoclonal IgG4 antibody
(AGEN2034), and to assess the maximum tolerated dose (MTD) in subjects with advanced solid
tumors. This study will also determine the RP2D of AGEN1181 monotherapy and in combination
This Phase 1/2 study will enroll up to approximately 86 evaluable adult subjects with
refractory cancer (solid tumors) regardless of diagnosis. Subjects may be enrolled into the
Cohort 1: AGEN1181 every 3 weeks at 0.1, 0.3, 1, 2, and 4 mg/kg Cohort 2: AGEN1181 every 6
weeks at 1, 2, and 3 mg/kg Cohort 3: AGEN2034 every 2 weeks at 3 mgkg + AGEN1181 every 6
weeks at 0.1, 0.3, 1, 2, and 4 mg/kg.
The trial will consist of a 3+3 dose escalation that will evaluate different dose levels of
AGEN1181 monotherapy and in combination with AGEN2034. Each subject will stay on the dose
level an schedule assigned at trial entry. Subjects can be replaced for any reason other than
a DLT. Subjects will receive treatment for ≤ 2 years or until PD, 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, pharmacodynamics, and
clinical activity in selected cancer types at dose levels (AGEN1181 monotherapy and
combination therapy with AGEN2034) determined as potentially effective. Indications of
interest include, but are not to limited to Non-Small-Cell Lung Cancer (NSCLC) refractory to
prior PD-1/PD-L1 inhibitor treatment, melanoma refractory to prior PD-1/PD-L1 inhibitor
treatment, hepatocellular carcinoma (HCC), endometrial cancer, and angiosarcoma.
For inclusion in the trial, all of the following inclusion criteria must be fulfilled, as
no waivers will be permitted:
1. Provision of signed and dated written informed consent prior to any study specific
procedures. Participation in pharmacogenomics (PGx) testing is optional.
2. ≥ 18 years of age.
3. Histologically or cytologically confirmed diagnosis of metastatic or locally advanced
solid tumor for which no standard therapy is available or standard therapy has failed.
4. Measurable disease on imaging based on Response Evaluation Criteria in Solid Tumors
version 1.1 (RECIST 1.1).
5. Life expectancy of ≥ 3 months and Eastern Cooperative Oncology Group (ECOG)
performance status of 0 or 1.
6. Adequate organ and bone marrow reserve function, as indicated by the following
1. Adequate hematological function, defined as absolute neutrophil count (ANC) ≥ 1.5
× 109/L, platelet count ≥ 100 × 109/L, and hemoglobin ≥ 8 g/dL without recent
transfusion (defined as a transfusion that has occurred within 2 weeks of the
2. Adequate liver function, defined as total bilirubin level ≤ 1.5 × institutional
upper limit of normal (IULN), aspartate aminotransferase (AST) ≤ 2.5 × IULN, and
alanine aminotransferase (ALT) ≤ 2.5 × IULN.
3. Adequate renal function defined as creatinine ≤ 1.5 × IULN OR measured or
calculated creatinine clearance ≥ 40 mL/min per institutional standard.
Assessment methods should be recorded.
4. Adequate coagulation, defined as international normalized ratio (INR) or
prothrombin time ≤ 1.5 × IULN and activated partial thromboplastin time (aPTT) ≤
1.5 × IULN (unless patient receiving anticoagulant therapy).
7. No history of prior or concomitant malignancy that requires other active treatment.
8. Patients must provide a sufficient and adequate formalin-fixed paraffin embedded
(FFPE) 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
9. Female patients 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:
1. ≥ 45 years of age and has not had menses for >1 year.
2. Amenorrheic for > 2 years without a hysterectomy and/or oophorectomy and follicle
stimulating hormone value in the postmenopausal range upon pretrial (screening)
3. Status is post-hysterectomy, -oophorectomy, or -tubal ligation.
10. Female patients 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 patient.
11. Male patients 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 patient
For inclusion in the trial, subject must meet none of the following exclusion criteria, as
no waivers will be permitted:
1. 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.
2. 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
3. Patients 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.
4. Persistent toxicity of National Cancer Institute (NCI) Common Terminology Criteria for
Adverse Events (CTCAE) version 5.0 Grade > 1 severity that is related to prior
Note: Sensory neuropathy or alopecia of Grade ≤ 2 are acceptable.
5. 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).
6. 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.
7. 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.
Patients 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.
8. 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: Patients 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). In C-800-01 Agenus, Inc. Protocol Amendment
4 22 July 2020 Confidential Page 15 of 124 addition, 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 trial medication.
9. Active or history of autoimmune disease that requires systemic treatment within 2
years of the start of study drug (i.e., with use of disease-modifying agents,
corticosteroids, or immunosuppressive drugs). Note: Patients with autoimmune
conditions requiring hormone replacement therapy or topical treatments are eligible.
10. Has had an allogeneic tissue/solid organ transplant, except for corneal transplants.
11. Active infection requiring treatment.
12. Known history of human immunodeficiency virus (HIV) type 1 or 2 antibodies.
13. Known active infection with hepatitis B and/or hepatitis C virus.
14. Clinically significant (i.e., 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.
15. 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 patient's participation for the full duration of the trial, or is not in the best
interest of the patient to participate, in the opinion of the treating Investigator.
16. Known psychiatric or substance abuse disorder that would interfere with cooperation
with the requirements of the trial.
17. Legally incapacitated or has limited legal capacity.
18. Pregnant or breastfeeding.