Skip to main content
Clinical Trials/NCT03860272
NCT03860272
Active, not recruiting
Phase 1

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

Agenus Inc.18 sites in 2 countries499 target enrollmentStarted: March 20, 2019Last updated:

Overview

Phase
Phase 1
Status
Active, not recruiting
Enrollment
499
Locations
18
Primary Endpoint
DLT Of Botensilimab

Overview

Brief Summary

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.

Detailed Description

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.

Study Design

Study Type
Interventional
Allocation
Non Randomized
Intervention Model
Single Group
Primary Purpose
Treatment
Masking
None

Eligibility Criteria

Ages
18 Years to — (Adult, Older Adult)
Sex
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, except for prostate cancer.
  • Life expectancy of ≥ 3 months and Eastern Cooperative Oncology Group performance status of 0 or
  • 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) (except for participants with Gilbert syndrome who must have a total bilirubin level of ≤ 3.0 × 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 (mL)/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) or stable known coagulopathy with sponsor approval.

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; for tyrosine kinase inhibitor or similar within 4 × half-life prior to first dose of study drug. A 1-week washout is permitted for palliative radiation to non-central nervous system disease, with Sponsor approval.
  • Participants who have received prior CTLA-4 therapy may be enrolled in selected indications upon agreement with the Sponsor.
  • Persistent toxicity of NCI CTCAE version 5.0 Grade \> 1 severity that is related to prior therapy. Note: Sensory neuropathy, hypothyroidism or alopecia of Grade ≤ 2 are acceptable. Other Grade 2 toxicities of prior treatments that are controlled with medication (for example, diabetes or hypertension) may be permitted with sponsor approval.
  • 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).
  • History of:
  • Severe (Grade ≥ 3) hypersensitivity reaction to a fully human monoclonal antibodies
  • Immune-related adverse event requiring treatment with systemic steroids for \> 7 days excluding Grade 1 or 2 rash.
  • Interstitial lung disease or lung disease which may interfere with the assessment of pneumonitis.

Arms & Interventions

3-Week Monotherapy

Experimental

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.

Intervention: Botensilimab (Drug)

6-Week Monotherapy

Experimental

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.

Intervention: Botensilimab (Drug)

6-Week Combination Therapy

Experimental

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.

Intervention: Botensilimab (Drug)

6-Week Combination Therapy

Experimental

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.

Intervention: Balstilimab (Drug)

Outcomes

Primary Outcomes

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.

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.

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.

Secondary Outcomes

  • Objective Response Rate (ORR) According To Response Evaluation Criteria In Solid Tumors Version 1.1 (RECIST 1.1)(First dose through up to 2 years)
  • DCR According to PCWG3(First study dose through 24 weeks)
  • Overall Survival Time(First study dose through up to 3 years)
  • Minimum Drug Concentration At Steady-state (Cmin-ss)(First study dose (pre-dose) through 3 months following last study dose (up to 2 years))
  • Disease Control Rate (DCR) According To RECIST 1.1(First study dose through 24 weeks)
  • Volume Of Distribution (Vd)(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-∞)](First study dose (pre-dose) through 3 months following last study dose (up to 2 years))
  • Terminal Elimination Half-life (t1/2)(First study dose (pre-dose) through 3 months following last study dose (up to 2 years))
  • Systemic Clearance (CL)(First study dose (pre-dose) through 3 months following last study dose (up to 2 years))
  • Anti-drug Antibodies (ADAs)(First study dose (pre-dose) through 3 months following last study dose (up to 2 years))
  • ORR According to Prostate Cancer Working Group 3 (PCWG3)(First dose through up to 2 years)
  • Progression-free Survival (PFS) According To RECIST 1.1(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(First study dose to first observation of documented disease progression (or death within 12 weeks of last tumor assessment) (up to 2 years))
  • Maximum Drug Concentration At Steady-state (Cmax-ss)(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)(First study dose (pre-dose) through 3 months following last study dose (up to 2 years))
  • Duration Of Response (DOR) According To RECIST 1.1(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(From first dose to first observation of documented disease progression (or death within 12 weeks of last tumor assessment) (up to 2 years))
  • Terminal Elimination Rate Constant (λz)(First study dose (pre-dose) through 3 months following last study dose (up to 2 years))

Investigators

Sponsor Class
Industry
Responsible Party
Sponsor

Study Sites (18)

Loading locations...

Similar Trials

Related News

Agenus Reports Promising Results for Botensilimab-Balstilimab Combination in Treatment-Refractory Ovarian Cancer- Agenus published clinical results showing botensilimab plus balstilimab achieved a 23% overall response rate and 31% clinical benefit rate in heavily pretreated, treatment-refractory ovarian cancer patients. - The combination demonstrated durable responses with a median duration of 9.7 months and median overall survival of 14.8 months in a population historically resistant to immunotherapy. - The study enrolled 44 women with treatment-refractory ovarian cancer, with nearly three-quarters being platinum-resistant or platinum-refractory patients. - The treatment showed a manageable safety profile with most common adverse events being diarrhea/colitis (43%), fatigue and nausea (36%), and no treatment-related deaths reported.Botensilimab Plus Balstilimab Shows Durable Responses in Refractory Metastatic Sarcoma- Combination therapy with botensilimab and balstilimab demonstrates a 23% overall response rate in patients with refractory metastatic sarcoma. - Angiosarcoma subgroup shows a notable 39% overall response rate, including responses in visceral subtypes, typically resistant to immunotherapy. - The median duration of response was 21.7 months, indicating the potential for long-lasting benefits in responding patients. - The safety profile of the combination remains consistent, with manageable immune-related toxicities and no new safety signals.Novel Sarcoma Therapies Show Promise in Early-Phase Studies at ESMO 2024- Palbociclib plus retifanlimab demonstrates a 14.3% objective response rate in patients with advanced dedifferentiated liposarcoma, warranting further investigation. - Regorafenib maintenance therapy after doxorubicin-based chemotherapy significantly improves progression-free survival in patients with non-adipocytic soft tissue sarcomas. - Botensilimab plus balstilimab shows a 23% objective response rate across various refractory metastatic sarcomas, with a notable 39% in cutaneous or visceral angiosarcoma.FDA Advises Against Accelerated Approval for Botensilimab/Balstilimab in MSS Colorectal Cancer Despite Phase 3 Advancement- The FDA advised against accelerated approval of botensilimab plus balstilimab for relapsed/refractory microsatellite stable metastatic colorectal cancer without liver metastases, citing concerns that objective response rates may not translate to survival benefit. - Phase 2 trial data showed the combination achieved a 19.4% objective response rate with the 75 mg botensilimab dose, significantly higher than the 0% response rate seen with standard of care treatment. - Despite the regulatory setback, Agenus and the FDA agreed on dosing for a phase 3 study, with botensilimab 75 mg every 6 weeks for up to 4 doses plus balstilimab 240 mg every 2 weeks for up to 2 years. - The company remains committed to advancing the combination therapy and is exploring partnership opportunities to conduct the phase 3 trial in the United States.FDA Grants Fast Track Designation to Botensilimab Plus Balstilimab for Non-MSI-H/dMMR mCRC- The FDA has granted Fast Track designation to botensilimab plus balstilimab for treating non-MSI-H/dMMR metastatic colorectal cancer (mCRC). - The designation targets heavily pretreated patients resistant or intolerant to standard therapies, including fluoropyrimidine, oxaliplatin, irinotecan, VEGF inhibitors, EGFR inhibitors, and BRAF inhibitors. - Phase 1a/b trial data showed an overall response rate of 23% and a disease control rate of 76% in patients with microsatellite stable, refractory mCRC treated with the combination. - The median overall survival was not reached in the overall population, with a 12-month overall survival rate of 63%, highlighting the potential of this combination in a high unmet need setting.