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A Study of AGEN2034 in Advanced Tumors and Cervical Cancer

A Phase 1/2, Open-Label, Multiple Ascending Dose Trial to Investigate the Safety, Tolerability, Pharmacokinetics, Biological, and Clinical Activity of AGEN2034 in Subjects With Metastatic or Locally Advanced Solid Tumors, With Expansion to Second Line Cervical Cancer

Status
Completed
Phases
Phase 1Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03104699
Enrollment
211
Registered
2017-04-07
Start date
2017-04-11
Completion date
2022-06-15
Last updated
2025-07-30

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Advanced Cancer, Cervical Cancer

Keywords

Antibodies, Immunologic effects, Physiological Effects of Drugs

Brief summary

This is a 2-part trial: a Phase 1, open-label, dose-escalation study in participants with metastatic or locally advanced solid tumors, with a consecutive Phase 2 expansion to evaluate efficacy in participants with recurrent, unresectable, or metastatic (advanced) cervical cancer that has progressed after a platinum-based treatment regimen.

Detailed description

Phase 1: Dose Escalation Phase 1 will consist of a standard 3+3 dose escalation with the following escalating dose levels and schedules: Part A1: 1, 3, and 10 milligrams/kilogram (mg/kg) administered every 2 weeks Part A2: 6 and 10 mg/kg every 3 weeks Each participant will stay on the dose level and schedule assigned at trial entry. Participants will receive AGEN2034 for a maximum of 2 years or until confirmed progression, unacceptable toxicity, or any criterion for stopping the study drug or withdrawal from the trial occurs. A Safety Monitoring Committee (SMC) will assess safety; decide on dose-escalation and opening of backfill enrollment; define the recommended Phase 2 dose (RP2D); and determine opening of the Phase 2 cohorts. In Part A1, the first participant of each cohort will be observed for 16 days (that is, ≥48 hours after second dose) for occurrence of dose-limiting toxicity (DLT) before the second participant is administered trial medication. Thereafter, within each cohort, consecutively enrolled participants may initiate treatment ≥48 hours after the prior enrolled participant-initiated treatment. Dose escalation will continue until the maximum tolerated dose (MTD) is reached or the maximum planned dose level (10.0 mg/kg) is shown to be safe. The MTD is defined as the dose below which ≥2 DLTs are observed. Once Part A1 is completed, enrollment to Part A2 will begin. If \<2 DLTs are observed in Part A1 at the maximum planned dose of 10 mg/kg every 2 weeks, open enrollment to Part A2 will begin with enrollment of 10 participants at 6 mg/kg every 3 weeks, followed by open enrollment of 10 participants at 10 mg/kg every 3 weeks. If ≥2 DLTs are observed in Part A1, at the maximum planned dose in Part A1, the standard 3+3 dose escalation will resume with Part A2 where consecutively enrolled participants in dose escalation may initiate treatment ≥48 hours after the prior enrolled participant-initiated treatment. For cohorts in dose escalation, concurrent with the 3+3 dose escalation schema, additional participants will be backfilled to lower dose levels to ensure that each cohort enrolls a total of 10 participants. Participants enrolled to backfill cohorts may be enrolled simultaneously, without sequential dosing (that is, not required to wait 48 hours between 2 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. Phase 2: Dose Expansion To further characterize safety and efficacy, participants with recurrent, unresectable, or metastatic cervical cancer will be enrolled in Phase 2 and receive the RP2D of AGEN2034 (3 mg/kg every 2 weeks) for a maximum of 2 years or until confirmed progression, unacceptable toxicity, or any criterion for stopping the study drug or withdrawal from the trial occurs. An SMC will assess safety, and an Independent Data Monitoring Committee will evaluate safety and efficacy.

Interventions

Anti-programmed cell death protein-1 (PD-1) Monoclonal Antibody

Sponsors

Agenus Inc.
Lead SponsorINDUSTRY

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

1. Voluntarily agree to participate by giving written informed consent. Participation in pharmacogenomics testing is optional. 2. Be ≥18 years of age. 3. Diagnosis and prior systemic treatment: 1. Phase 1: Have a histologically or cytologically confirmed diagnosis of a metastatic or locally advanced solid tumor for which no standard therapy is available or standard therapy has failed. 2. Phase 2: I. Have (1) a histologically or cytologically confirmed diagnosis of squamous-cell carcinoma, adenosquamous carcinoma, or adenocarcinoma of the cervix, and (2) metastatic, locally advanced, and/or unresectable 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 relapsed after a platinum-based treatment (first line) regimen for advanced (recurrent, unresectable, or metastatic) disease; Note: Participants who have received \>1 prior systemic treatment regimen for their advanced or metastatic disease will be eligible in the following cases: Participant receiving chemotherapy concurrently with primary radiation (for example, weekly cisplatin) or participant receiving adjuvant chemotherapy following completion of radiation therapy (for example, paclitaxel and carboplatin for ≤4 cycles) and progressed within 6 months after treatment completion. 4. Measurable disease - based on investigator assessment 1. Phase 1: Have objective evidence of disease; the presence of measurable disease is not required. 2. Phase 2: Have measurable disease on imaging based on Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1). Note: Participants must have at least one target lesion to be used to assess response, as defined by RECIST 1.1. Tumors within a previously irradiated field will be designated as non-target lesions unless progression is documented or a biopsy is obtained to confirm persistence at least 90 days following completion of radiation therapy. Note: Measurable disease by RECIST 1.1 must be confirmed by independent central radiologic review prior to first dose. Participants without centrally confirmed measurable disease at baseline will not be eligible for this trial. 5. Have a life expectancy of at least 3 months and an Eastern Cooperative Oncology Group performance status of 0 or 1. 6. Have adequate organ function as indicated by the following laboratory values: 1. Adequate hematological function defined by absolute neutrophil count ≥1.5 x 10\^9/liter (L), platelet count ≥100 x 10\^9/L, and stable hemoglobin ≥8 grams/deciliter (without transfusions within 1 week before first dose). 2. Adequate hepatic function based by a total bilirubin level ≤ the institutional upper limit of normal (IULN), aspartate aminotransferase level ≤2.5 x IULN, alanine aminotransferase level ≤2.5 x IULN, and alkaline phosphatase ≤2.5 x IULN. 3. Adequate renal function defined as creatinine ≤1.5 x IULN or calculated creatinine clearance ≥50 milliliters/minute for participants with creatinine levels \>1.5 x IULN (if no local guideline is available, creatinine clearance should be calculated using the Cockcroft-Gault Method). 4. Adequate coagulation defined by international normalized ratio or prothrombin time ≤1.5 x IULN (unless the participant is receiving anticoagulant therapy); and activated partial thromboplastin time ≤1.5 x IULN (unless the participant is receiving anticoagulant therapy) 7. Other than the cancer for which the participant is enrolled, have no history of prior malignancy, with the exception of basal cell carcinoma of the skin, superficial bladder cancer, squamous-cell carcinoma of the skin, or has undergone potentially curative therapy with no evidence of that disease recurrence for 5 years since initiation of that therapy. 8. In Phase 2, participants must provide a sufficient and adequate formalin-fixed paraffin-embedded tumor tissue sample preferably from the most recent biopsy of a tumor lesion, collected either at the time of or after the diagnosis of advanced or metastatic disease has been made and from a site not previously irradiated. If no tumor tissue is available, a fresh biopsy will be required. Note: Tissue from needle or excisional biopsy or from resection is required. 9. Female participants must have a negative serum pregnancy test at screening (within 72 hours before first dose of study drug) if of childbearing potential or be of non-childbearing potential. Non-childbearing potential is defined as (by other than medical reasons): 1. ≥45 years of age and has not menstruated for greater than 1 year, 2. Amenorrheic for \<2 years without a hysterectomy and oophorectomy and a follicle-stimulating hormone value in the postmenopausal range upon pretrial (screening) evaluation, 3. Whose status is post hysterectomy, oophorectomy or tubal ligation. 10. If of childbearing potential, female participants must be willing to use 2 highly effective methods (defined in the informed consent form \[ICF\]) throughout the study, starting with the screening visit through 120 days after the last dose of study treatment. Note: Abstinence is acceptable if this is the established and preferred contraception for the participant. 11. Male participants with a female partner(s) of childbearing potential must agree to use 2 highly effective methods (defined in the ICF) throughout the trial starting with the screening visit through 120 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 for the participant. 12. Is willing and able to comply with the requirements of the protocol.

Exclusion criteria

1. Is 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 4 weeks before the first dose of treatment. 2. Has an inadequate washout period prior to first dose of study drug defined as: 1. Received systemic cytotoxic chemotherapy or biological therapy within 3 weeks before first dose, 2. Received radiation therapy within 3 weeks before first dose, or 3. Had major surgery within 4 weeks before first dose. 3. Has received prior therapy with: 1. Any antibody/drug targeting T-cell co-regulatory proteins (immune checkpoints) such as anti-PD-1, anti-programmed cell death ligand 1, or anti-cytotoxic T-lymphocyte antigen 4 (CTLA-4) antibodies 2. For Phase 2: \>1 systemic treatment regimen for the advanced (recurrent, unresectable, or metastatic) cervical cancer for which the participant is considered for the study Note: In Phase 1, prior treatment with a CTLA-4 antibody is permissible for participants with metastatic melanoma. 4. Has persisting toxicity related to prior therapy of National Cancer Institute Common Terminology Criteria for Adverse Events version 4.03 (NCI CTCAE) Grade \>1 severity. Note: Sensory neuropathy or alopecia of Grade ≤2 is acceptable. 5. Is 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. Has known severe hypersensitivity reactions to fully human monoclonal antibodies (NCI CTCAE Grade ≥3), any history of anaphylaxis, or uncontrolled asthma. 7. Is receiving systemic corticosteroid ≤7 days prior to the first dose of trial treatment or receiving any other form of systemic immunosuppressive medication (corticosteroid use on study for management of immune-related adverse events, and/or a premedication for IV contrast allergies/reactions is allowed). Participants who are receiving daily corticosteroid replacement therapy are an exception to this rule. Examples of permitted therapy are daily prednisone at doses of 5 to 7.5 mg or equivalent hydrocortisone dose, and steroid therapy administered by topical, intraocular, intranasal, and/or inhalation routes. 8. Has a central nervous system 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 (based on 2 sets of brain images, performed ≥4 weeks apart, and obtained after the brain metastases treatment). In addition, any neurologic symptoms that developed either as a result of the brain metastases or their treatment must have resolved or be minimal and be expected as sequelae from treated lesions. For individuals who received steroids as part of brain metastases treatment, steroids must be discontinued ≥7 days prior to first dose of study drug. 9. Has active or history of autoimmune disease that has required systemic treatment within 2 years of the start of trial treatment (that is, with use of disease modifying agents, corticosteroids or immunosuppressive drugs). Replacement therapy (that is, thyroxine, insulin, or physiologic corticosteroid replacement therapy for adrenal or pituitary insufficiency, etc.) is not considered a form of systemic treatment. Note: Participants with type 1 diabetes, vitiligo, psoriasis, hypo-, or hyperthyroid disease not requiring immunosuppressive treatment are eligible. 10. Has had an allogeneic tissue/solid organ transplant. 11. Has or had interstitial lung disease or has had a history of pneumonitis that has required oral or IV corticosteroids. 12. Has an active infection requiring intravenous systemic therapy. 13. Has known history of Human Immunodeficiency Virus (HIV) (HIV 1/2 antibodies). 14. Has known active Hepatitis B, Hepatitis C or tuberculosis. Active Hepatitis B is defined as a known positive Hepatitis B surface antigen result. Active Hepatitis C is defined by a known positive Hepatitis C antibody result and known quantitative Hepatitis C virus ribonucleic acid results greater than the lower limits of detection of the assay. 15. Has clinically significant (that is, active) cardiovascular disease: cerebral vascular accident/stroke or myocardial infarction within 6 months before enrollment, unstable angina, congestive heart failure (New York Heart Association class ≥II), or serious uncontrolled cardiac arrhythmia requiring medication. 16. Has a history or current evidence of any condition, therapy, 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. 17. Has known psychiatric or substance abuse disorders that would interfere with cooperation with the requirements of the trial. 18. Is, at the time of signing informed consent, a regular user (including recreational use) of any illicit drugs or had a recent history (within the last year) of substance abuse (including alcohol). 19. Is legally incapacitated or has limited legal capacity. 20. Is pregnant or breastfeeding or expecting to conceive or father children within the projected duration of the trial, starting with the screening visit through 120 days after the last dose of study treatment.

Design outcomes

Primary

MeasureTime frameDescription
Phase 1: Number of Participants Experiencing Dose-limiting Toxicities (DLTs) for Balstilimab21 daysA DLT was defined as any treatment-related toxicity that was National Cancer Institute Common Terminology Criteria for Adverse Event Grade ≥3, confirmed by the safety monitoring committee to be relevant for the study drug treatment, and that occurred during the first 3 weeks of balstilimab treatment in the dose escalation portion of the study (DLT evaluation period).
Phase 1: Number of Participants Experiencing Treatment-emergent Adverse Events (TEAEs)Up to 3 yearsAn adverse event (AE) was any untoward medical occurrence in a participant or clinical investigation participant administered a pharmaceutical product, which did not necessarily have a causal relationship with the treatment. TEAEs were AEs with onset dates during the on-treatment period, or the worsening of an event during the on-treatment period. A summary of all Serious Adverse Events and Other Adverse Events (nonserious), regardless of causality, is located in the 'Reported Adverse Events' Section.
Phase 2: Objective Response Rate (ORR) as Determined by an Independent Endpoint Review Committee (IERC)Up to 3 yearsORR was defined as percentage of participants with a best overall response (BOR) of complete response (CR) or partial response (PR), as determined by an IERC per Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1). BOR was defined as the best response recorded from the start of the study treatment until the end of treatment. CR was defined as disappearance of all target lesions, and PR was defined as at least a 30% decrease in the sum of diameters of target lesions, taking as reference the baseline sum diameters.

Secondary

MeasureTime frameDescription
Phase 1: Number of Participants With Serum Anti-drug Antibodies (ADAs) for BalstilimabUp to 2.5 yearsBlood samples were collected for serum balstilimab ADA determination.
Phase 2: Number of Participants Experiencing TEAEsUp to 3 yearsAn AE was any untoward medical occurrence in a participant or clinical investigation participant administered a pharmaceutical product, which did not necessarily have a causal relationship with the treatment. TEAEs were AEs with onset dates during the on-treatment period, or the worsening of an event during the on-treatment period. A summary of all Serious Adverse Events and Other Adverse Events (nonserious) regardless of causality is located in the 'Reported Adverse Events' Section.
Phase 2: Cmax of BalstilimabDay 1 (Pre-dose up to 24 hours post dose) of Cycle 1 and Cycle 2 (2 weeks/cycle) (up to 2 weeks)Blood samples were collected for serum balstilimab concentration determinations. Results are reported in μg/mL.
Phase 2: AUC0-last of BalstilimabDay 1 (Pre-dose up to 24 hours post dose) of Cycle 1 and Cycle 2 (2 weeks/cycle) (up to 2 weeks)Blood samples were collected for serum balstilimab concentration determinations. Results are reported in day\*μg/mL.
Phase 2: Number of Participants With Serum ADAs for BalstilimabUp to 2.5 yearsBlood samples were collected for serum balstilimab ADA determination.
Phase 2: ORR as Determined by the InvestigatorUp to 3 yearsORR was defined as percentage of participants with a BOR of CR or PR, as determined by the investigator per RECIST 1.1. BOR was defined as the best response recorded from the start of the study treatment until the end of treatment. CR was defined as disappearance of all target lesions, and PR was defined as at least a 30% decrease in the sum of diameters of target lesions, taking as reference the baseline sum diameters.
Phase 1: Receptor Occupancy of Circulating T Cells4 hours after the first dose (Cycle 1 Day 1) and immediately prior to the second dose (Cycle 2 Day 1) (2-3 weeks/cycle)The percentage of PD-1 receptor occupancy on circulating T cells was measured as an indication of target engagement. An increase in percent occupancy indicates a potential increase in drug effectiveness.
Phase 2: Disease Control Rate (DCR) as Determined by an IERCUp to 3 yearsDCR was defined as the percentage of participants with CR, PR, or stable disease (SD) for at least 12 weeks. CR was defined as disappearance of all target lesions, PR was defined as at least a 30% decrease in the sum of diameters of target lesions, taking as reference the baseline sum diameters. SD was defined as neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for PD, taking as reference the smallest sum diameters while on study. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (this included the baseline sum if that is the smallest on study).
Phase 2: Tumor Control Rate (TCR) as Determined by an IERCUp to 3 yearsTCR was defined as percentage of participants who had a BOR of either SD or a confirmed objective response (CR or PR). CR was defined as disappearance of all target lesions, PR was defined as at least a 30% decrease in the sum of diameters of target lesions, taking as reference the baseline sum diameters. SD was defined as neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for PD, taking as reference the smallest sum diameters while on study. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (this included the baseline sum if that is the smallest on study).
Phase 2: Time to Response (TTR) as Determined by an IERCUp to 3 yearsTTR was defined as the time from the first dose date to first observation of confirmed response.
Phase 2: Progression-free Survival (PFS)Up to 3 yearsPFS was defined as time from first treatment administration to first observation of documented PD (or death within 12 weeks after last tumor assessment), per RECIST 1.1, as determined by an IERC and investigator. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (this included the baseline sum if that is the smallest on study). Participants without an event at analysis cutoff date were censored on date of last tumor assessment.
Phase 2: Overall Survival (OS)Up to 3 yearsOS was defined as time from start of treatment to death. For participants who were still alive at the time of data cutoff for trial analysis or who were lost to follow-up, survival was censored at the last recorded date that the participant was known to have been alive as of the cutoff date for analysis.
Phase 2: Duration of Response (DOR)Up to 3 yearsDOR was defined as time from first observation of response to first observation of documented progressive disease (PD) (or death within 12 weeks after last tumor assessment), per RECIST 1.1 and as determined by an IERC and the investigator. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (this included the baseline sum if that is the smallest on study). Participants without an event at analysis cutoff date were censored on date of last tumor assessment.
Phase 1: Maximum Observed Concentration (Cmax) of BalstilimabDay 1 (Pre-dose up to 24 hours post dose) of Cycle 1 and Cycle 2 (2-3 weeks/cycle) (up to 3 weeks)Blood samples were collected for serum balstilimab concentration determinations. Results are reported as micrograms/milliliter (ug/mL).
Phase 1: Area Under the Drug Concentration-time Curve From Time Zero to the Last Quantifiable Concentration (AUC0-last) of BalstilimabDay 1 (Pre-dose up to 24 hours post dose) of Cycle 1 and Cycle 2 (2-3 weeks/cycle) (up to 3 weeks)Blood samples were collected for serum balstilimab concentration determinations. Results are reported as hours\*micrograms/milliliter (h\*µg/mL).

Countries

Australia, Belgium, Brazil, Chile, Estonia, France, Poland, Spain, United States

Participant flow

Participants by arm

ArmCount
Phase 1: Balstilimab Dose 1
Participants received 1 mg/kg Q2W balstilimab for up to 24 months.
10
Phase 1: Balstilimab Dose 2
Participants received 3 mg/kg Q2W balstilimab for up to 24 months.
10
Phase 1: Balstilimab Dose 3
Participants received 6 mg/kg Q3W balstilimab for up to 24 months.
10
Phase 1: Balstilimab Dose 4
Participants received 10 mg/kg Q2W balstilimab for up to 24 months.
10
Phase 1: Balstilimab Dose 5
Participants received 10 mg/kg Q3W balstilimab for up to 24 months.
10
Phase 2: Balstilimab Recommended Phase 2 Dose
Participants received 3 mg/kg Q2W balstilimab for a maximum of 24 months or until progression, unacceptable toxicity, stopping the study drug, or withdrawal from the study.
161
Total211

Withdrawals & dropouts

PeriodReasonFG000FG001FG002FG003FG004FG005
Phase 1: Dose EscalationCompleted Follow Up221020
Phase 1: Dose EscalationDeath630110
Phase 1: Dose EscalationDisease Progression020000
Phase 1: Dose EscalationLost to Follow-up011000
Phase 1: Dose EscalationPhysician Decision002100
Phase 1: Dose EscalationProgressive Disease000010
Phase 1: Dose EscalationProtocol Violation000020
Phase 1: Dose EscalationWithdrawal by Subject224840
Phase 2: Dose ExpansionAdministrative Study Closure0000013
Phase 2: Dose ExpansionDeath00000107
Phase 2: Dose ExpansionLost to Follow-up000005
Phase 2: Dose ExpansionParticipant Left to Participate in Another Trial000001
Phase 2: Dose ExpansionProgressive Disease000001
Phase 2: Dose ExpansionWithdrawal by Subject000006

Baseline characteristics

CharacteristicPhase 1: Balstilimab Dose 1Phase 1: Balstilimab Dose 2Phase 1: Balstilimab Dose 3Phase 1: Balstilimab Dose 4Phase 1: Balstilimab Dose 5Phase 2: Balstilimab Recommended Phase 2 DoseTotal
Age, Customized
Adults (18-64 years)
7 Participants9 Participants6 Participants7 Participants6 Participants119 Participants154 Participants
Age, Customized
From 65-84 years
3 Participants1 Participants4 Participants3 Participants4 Participants42 Participants57 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
1 Participants0 Participants2 Participants1 Participants1 Participants38 Participants43 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
9 Participants10 Participants8 Participants9 Participants9 Participants39 Participants84 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants0 Participants84 Participants84 Participants
Race/Ethnicity, Customized
Asian
0 Participants3 Participants1 Participants1 Participants1 Participants1 Participants7 Participants
Race/Ethnicity, Customized
Black or African American
2 Participants1 Participants0 Participants0 Participants0 Participants2 Participants5 Participants
Race/Ethnicity, Customized
Brown
0 Participants0 Participants0 Participants0 Participants0 Participants1 Participants1 Participants
Race/Ethnicity, Customized
Mixed
0 Participants0 Participants0 Participants0 Participants0 Participants3 Participants3 Participants
Race/Ethnicity, Customized
Not Reported (France)
0 Participants0 Participants0 Participants0 Participants0 Participants81 Participants81 Participants
Race/Ethnicity, Customized
Romanian
0 Participants0 Participants0 Participants0 Participants0 Participants1 Participants1 Participants
Race/Ethnicity, Customized
White
8 Participants6 Participants9 Participants9 Participants9 Participants72 Participants113 Participants
Sex: Female, Male
Female
8 Participants8 Participants9 Participants9 Participants8 Participants161 Participants203 Participants
Sex: Female, Male
Male
2 Participants2 Participants1 Participants1 Participants2 Participants0 Participants8 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
EG004
affected / at risk
EG005
affected / at risk
deaths
Total, all-cause mortality
6 / 103 / 100 / 101 / 101 / 10108 / 161
other
Total, other adverse events
10 / 1010 / 1010 / 1010 / 1010 / 10158 / 161
serious
Total, serious adverse events
5 / 103 / 105 / 103 / 102 / 1090 / 161

Outcome results

Primary

Phase 1: Number of Participants Experiencing Dose-limiting Toxicities (DLTs) for Balstilimab

A DLT was defined as any treatment-related toxicity that was National Cancer Institute Common Terminology Criteria for Adverse Event Grade ≥3, confirmed by the safety monitoring committee to be relevant for the study drug treatment, and that occurred during the first 3 weeks of balstilimab treatment in the dose escalation portion of the study (DLT evaluation period).

Time frame: 21 days

Population: DLT Analysis Set: all participants who were enrolled for DLT evaluation (excluding participants enrolled to backfill cohorts) and either received all balstilimab administrations or stopped treatment due to a DLT during the DLT evaluation period. Here, 'Overall Number of Participants Analyzed' signifies those participants who were evaluable for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Phase 1: Balstilimab Dose 1Phase 1: Number of Participants Experiencing Dose-limiting Toxicities (DLTs) for Balstilimab0 Participants
Phase 1: Balstilimab Dose 2Phase 1: Number of Participants Experiencing Dose-limiting Toxicities (DLTs) for Balstilimab0 Participants
Phase 1: Balstilimab Dose 3Phase 1: Number of Participants Experiencing Dose-limiting Toxicities (DLTs) for Balstilimab0 Participants
Phase 1: Balstilimab Dose 4Phase 1: Number of Participants Experiencing Dose-limiting Toxicities (DLTs) for Balstilimab0 Participants
Phase 1: Balstilimab Dose 5Phase 1: Number of Participants Experiencing Dose-limiting Toxicities (DLTs) for Balstilimab0 Participants
Primary

Phase 1: Number of Participants Experiencing Treatment-emergent Adverse Events (TEAEs)

An adverse event (AE) was any untoward medical occurrence in a participant or clinical investigation participant administered a pharmaceutical product, which did not necessarily have a causal relationship with the treatment. TEAEs were AEs with onset dates during the on-treatment period, or the worsening of an event during the on-treatment period. A summary of all Serious Adverse Events and Other Adverse Events (nonserious), regardless of causality, is located in the 'Reported Adverse Events' Section.

Time frame: Up to 3 years

Population: Safety Analysis Set: all participants who received at least 1 dose of balstilimab.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Phase 1: Balstilimab Dose 1Phase 1: Number of Participants Experiencing Treatment-emergent Adverse Events (TEAEs)10 Participants
Phase 1: Balstilimab Dose 2Phase 1: Number of Participants Experiencing Treatment-emergent Adverse Events (TEAEs)10 Participants
Phase 1: Balstilimab Dose 3Phase 1: Number of Participants Experiencing Treatment-emergent Adverse Events (TEAEs)10 Participants
Phase 1: Balstilimab Dose 4Phase 1: Number of Participants Experiencing Treatment-emergent Adverse Events (TEAEs)10 Participants
Phase 1: Balstilimab Dose 5Phase 1: Number of Participants Experiencing Treatment-emergent Adverse Events (TEAEs)10 Participants
Primary

Phase 2: Objective Response Rate (ORR) as Determined by an Independent Endpoint Review Committee (IERC)

ORR was defined as percentage of participants with a best overall response (BOR) of complete response (CR) or partial response (PR), as determined by an IERC per Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1). BOR was defined as the best response recorded from the start of the study treatment until the end of treatment. CR was defined as disappearance of all target lesions, and PR was defined as at least a 30% decrease in the sum of diameters of target lesions, taking as reference the baseline sum diameters.

Time frame: Up to 3 years

Population: Intent-to-Treat Efficacy Analysis Set: all participants who received ≥1 dose of balstilimab with measurable disease at baseline (per IERC).

ArmMeasureValue (NUMBER)
Phase 1: Balstilimab Dose 1Phase 2: Objective Response Rate (ORR) as Determined by an Independent Endpoint Review Committee (IERC)15.6 percentage of participants
Secondary

Phase 1: Area Under the Drug Concentration-time Curve From Time Zero to the Last Quantifiable Concentration (AUC0-last) of Balstilimab

Blood samples were collected for serum balstilimab concentration determinations. Results are reported as hours\*micrograms/milliliter (h\*µg/mL).

Time frame: Day 1 (Pre-dose up to 24 hours post dose) of Cycle 1 and Cycle 2 (2-3 weeks/cycle) (up to 3 weeks)

Population: Pharmacokinetic Analysis Set: all participants who completed ≥1 balstilimab infusion and who had sufficient evaluable drug concentration measurements prior to and after treatment. Here, 'Number Analyzed' signifies those participants who were evaluable for this outcome measure at the specified time points.

ArmMeasureGroupValue (GEOMETRIC_MEAN)Dispersion
Phase 1: Balstilimab Dose 1Phase 1: Area Under the Drug Concentration-time Curve From Time Zero to the Last Quantifiable Concentration (AUC0-last) of BalstilimabCycle 1 Day 11265 h*µg/mLGeometric Coefficient of Variation 47.4
Phase 1: Balstilimab Dose 1Phase 1: Area Under the Drug Concentration-time Curve From Time Zero to the Last Quantifiable Concentration (AUC0-last) of BalstilimabCycle 2 Day 11477 h*µg/mLGeometric Coefficient of Variation 73.7
Phase 1: Balstilimab Dose 2Phase 1: Area Under the Drug Concentration-time Curve From Time Zero to the Last Quantifiable Concentration (AUC0-last) of BalstilimabCycle 1 Day 16470 h*µg/mLGeometric Coefficient of Variation 34.6
Phase 1: Balstilimab Dose 2Phase 1: Area Under the Drug Concentration-time Curve From Time Zero to the Last Quantifiable Concentration (AUC0-last) of BalstilimabCycle 2 Day 17725 h*µg/mLGeometric Coefficient of Variation 40.2
Phase 1: Balstilimab Dose 3Phase 1: Area Under the Drug Concentration-time Curve From Time Zero to the Last Quantifiable Concentration (AUC0-last) of BalstilimabCycle 1 Day 112632 h*µg/mLGeometric Coefficient of Variation 51.5
Phase 1: Balstilimab Dose 3Phase 1: Area Under the Drug Concentration-time Curve From Time Zero to the Last Quantifiable Concentration (AUC0-last) of BalstilimabCycle 2 Day 117479 h*µg/mLGeometric Coefficient of Variation 49.4
Phase 1: Balstilimab Dose 4Phase 1: Area Under the Drug Concentration-time Curve From Time Zero to the Last Quantifiable Concentration (AUC0-last) of BalstilimabCycle 2 Day 121298 h*µg/mLGeometric Coefficient of Variation 47.1
Phase 1: Balstilimab Dose 4Phase 1: Area Under the Drug Concentration-time Curve From Time Zero to the Last Quantifiable Concentration (AUC0-last) of BalstilimabCycle 1 Day 122294 h*µg/mLGeometric Coefficient of Variation 47.5
Phase 1: Balstilimab Dose 5Phase 1: Area Under the Drug Concentration-time Curve From Time Zero to the Last Quantifiable Concentration (AUC0-last) of BalstilimabCycle 1 Day 130751 h*µg/mLGeometric Coefficient of Variation 50.4
Phase 1: Balstilimab Dose 5Phase 1: Area Under the Drug Concentration-time Curve From Time Zero to the Last Quantifiable Concentration (AUC0-last) of BalstilimabCycle 2 Day 142266 h*µg/mLGeometric Coefficient of Variation 41
Secondary

Phase 1: Maximum Observed Concentration (Cmax) of Balstilimab

Blood samples were collected for serum balstilimab concentration determinations. Results are reported as micrograms/milliliter (ug/mL).

Time frame: Day 1 (Pre-dose up to 24 hours post dose) of Cycle 1 and Cycle 2 (2-3 weeks/cycle) (up to 3 weeks)

Population: Pharmacokinetic Analysis Set: all participants who completed ≥1 balstilimab infusion of study drug and who had sufficient evaluable drug concentration measurements prior to and after treatment. Here, 'Number Analyzed' signifies those participants who were evaluable for this outcome measure at the specified time points.

ArmMeasureGroupValue (GEOMETRIC_MEAN)Dispersion
Phase 1: Balstilimab Dose 1Phase 1: Maximum Observed Concentration (Cmax) of BalstilimabCycle 2 Day 120.3 ug/mLGeometric Coefficient of Variation 47
Phase 1: Balstilimab Dose 1Phase 1: Maximum Observed Concentration (Cmax) of BalstilimabCycle 1 Day 118.1 ug/mLGeometric Coefficient of Variation 34.3
Phase 1: Balstilimab Dose 2Phase 1: Maximum Observed Concentration (Cmax) of BalstilimabCycle 1 Day 171.9 ug/mLGeometric Coefficient of Variation 19.5
Phase 1: Balstilimab Dose 2Phase 1: Maximum Observed Concentration (Cmax) of BalstilimabCycle 2 Day 186.3 ug/mLGeometric Coefficient of Variation 30
Phase 1: Balstilimab Dose 3Phase 1: Maximum Observed Concentration (Cmax) of BalstilimabCycle 2 Day 1161 ug/mLGeometric Coefficient of Variation 27.5
Phase 1: Balstilimab Dose 3Phase 1: Maximum Observed Concentration (Cmax) of BalstilimabCycle 1 Day 1153 ug/mLGeometric Coefficient of Variation 23.7
Phase 1: Balstilimab Dose 4Phase 1: Maximum Observed Concentration (Cmax) of BalstilimabCycle 2 Day 1239 ug/mLGeometric Coefficient of Variation 28.2
Phase 1: Balstilimab Dose 4Phase 1: Maximum Observed Concentration (Cmax) of BalstilimabCycle 1 Day 1236 ug/mLGeometric Coefficient of Variation 26.6
Phase 1: Balstilimab Dose 5Phase 1: Maximum Observed Concentration (Cmax) of BalstilimabCycle 1 Day 1282 ug/mLGeometric Coefficient of Variation 28.4
Phase 1: Balstilimab Dose 5Phase 1: Maximum Observed Concentration (Cmax) of BalstilimabCycle 2 Day 1315 ug/mLGeometric Coefficient of Variation 25.5
Secondary

Phase 1: Number of Participants With Serum Anti-drug Antibodies (ADAs) for Balstilimab

Blood samples were collected for serum balstilimab ADA determination.

Time frame: Up to 2.5 years

Population: Safety Analysis Set: all participants who received at least 1 dose of balstilimab.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Phase 1: Balstilimab Dose 1Phase 1: Number of Participants With Serum Anti-drug Antibodies (ADAs) for Balstilimab3 Participants
Phase 1: Balstilimab Dose 2Phase 1: Number of Participants With Serum Anti-drug Antibodies (ADAs) for Balstilimab0 Participants
Phase 1: Balstilimab Dose 3Phase 1: Number of Participants With Serum Anti-drug Antibodies (ADAs) for Balstilimab0 Participants
Phase 1: Balstilimab Dose 4Phase 1: Number of Participants With Serum Anti-drug Antibodies (ADAs) for Balstilimab0 Participants
Phase 1: Balstilimab Dose 5Phase 1: Number of Participants With Serum Anti-drug Antibodies (ADAs) for Balstilimab0 Participants
Secondary

Phase 1: Receptor Occupancy of Circulating T Cells

The percentage of PD-1 receptor occupancy on circulating T cells was measured as an indication of target engagement. An increase in percent occupancy indicates a potential increase in drug effectiveness.

Time frame: 4 hours after the first dose (Cycle 1 Day 1) and immediately prior to the second dose (Cycle 2 Day 1) (2-3 weeks/cycle)

Population: Receptor Occupancy Analysis Set: all participants who completed ≥1 balstilimab infusion, with adequate measurements of PD-1 receptor occupancy on circulating T cells. Here, 'Number Analyzed' signifies those participants who were evaluable for this outcome measure at the specified time points.

ArmMeasureGroupValue (MEAN)Dispersion
Phase 1: Balstilimab Dose 1Phase 1: Receptor Occupancy of Circulating T CellsCycle 1 Day 173.2 percent occupancyStandard Deviation 11.95
Phase 1: Balstilimab Dose 1Phase 1: Receptor Occupancy of Circulating T CellsCycle 2 Day 167.7 percent occupancyStandard Deviation 16.93
Phase 1: Balstilimab Dose 2Phase 1: Receptor Occupancy of Circulating T CellsCycle 1 Day 169.4 percent occupancyStandard Deviation 5.52
Phase 1: Balstilimab Dose 2Phase 1: Receptor Occupancy of Circulating T CellsCycle 2 Day 161.6 percent occupancyStandard Deviation 1.7
Phase 1: Balstilimab Dose 4Phase 1: Receptor Occupancy of Circulating T CellsCycle 1 Day 176.6 percent occupancyStandard Deviation 2.95
Phase 1: Balstilimab Dose 4Phase 1: Receptor Occupancy of Circulating T CellsCycle 2 Day 172.1 percent occupancyStandard Deviation 8.29
Secondary

Phase 2: AUC0-last of Balstilimab

Blood samples were collected for serum balstilimab concentration determinations. Results are reported in day\*μg/mL.

Time frame: Day 1 (Pre-dose up to 24 hours post dose) of Cycle 1 and Cycle 2 (2 weeks/cycle) (up to 2 weeks)

Population: Pharmacokinetic Analysis Set: all participants who completed ≥1 balstilimab infusion and who had sufficient evaluable drug concentration measurements prior to and after treatment. Here, 'Number Analyzed' signifies those participants who were evaluable for this outcome measure at the specified time points.

ArmMeasureGroupValue (GEOMETRIC_MEAN)Dispersion
Phase 1: Balstilimab Dose 1Phase 2: AUC0-last of BalstilimabCycle 1 Day 1174 day*μg/mLGeometric Coefficient of Variation 46.3
Phase 1: Balstilimab Dose 1Phase 2: AUC0-last of BalstilimabCycle 2 Day 1184 day*μg/mLGeometric Coefficient of Variation 59.7
Secondary

Phase 2: Cmax of Balstilimab

Blood samples were collected for serum balstilimab concentration determinations. Results are reported in μg/mL.

Time frame: Day 1 (Pre-dose up to 24 hours post dose) of Cycle 1 and Cycle 2 (2 weeks/cycle) (up to 2 weeks)

Population: Pharmacokinetic Analysis Set: all participants who completed ≥1 balstilimab infusion and who had sufficient evaluable drug concentration measurements prior to and after treatment. Here, 'Number Analyzed' signifies those participants who were evaluable for this outcome measure at the specified time points.

ArmMeasureGroupValue (GEOMETRIC_MEAN)Dispersion
Phase 1: Balstilimab Dose 1Phase 2: Cmax of BalstilimabCycle 1 Day 155.4 μg/mLGeometric Coefficient of Variation 42.8
Phase 1: Balstilimab Dose 1Phase 2: Cmax of BalstilimabCycle 2 Day 156.6 μg/mLGeometric Coefficient of Variation 23.9
Secondary

Phase 2: Disease Control Rate (DCR) as Determined by an IERC

DCR was defined as the percentage of participants with CR, PR, or stable disease (SD) for at least 12 weeks. CR was defined as disappearance of all target lesions, PR was defined as at least a 30% decrease in the sum of diameters of target lesions, taking as reference the baseline sum diameters. SD was defined as neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for PD, taking as reference the smallest sum diameters while on study. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (this included the baseline sum if that is the smallest on study).

Time frame: Up to 3 years

Population: Intent-to-Treat Efficacy Analysis Set: all participants who received ≥1 dose of balstilimab with measurable disease at baseline (per IERC).

ArmMeasureValue (NUMBER)
Phase 1: Balstilimab Dose 1Phase 2: Disease Control Rate (DCR) as Determined by an IERC50.6 percentage of participants
Secondary

Phase 2: Duration of Response (DOR)

DOR was defined as time from first observation of response to first observation of documented progressive disease (PD) (or death within 12 weeks after last tumor assessment), per RECIST 1.1 and as determined by an IERC and the investigator. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (this included the baseline sum if that is the smallest on study). Participants without an event at analysis cutoff date were censored on date of last tumor assessment.

Time frame: Up to 3 years

Population: Intent-to-Treat Efficacy Analysis Set: all participants who received ≥1 dose of balstilimab with measurable disease at baseline (per IERC). Here, 'Overall Number of Participants Analyzed' and 'Number Analyzed' signify those participants who were evaluable for this outcome measure.

ArmMeasureGroupValue (MEDIAN)
Phase 1: Balstilimab Dose 1Phase 2: Duration of Response (DOR)IERCNA months
Phase 1: Balstilimab Dose 1Phase 2: Duration of Response (DOR)InvestigatorNA months
Secondary

Phase 2: Number of Participants Experiencing TEAEs

An AE was any untoward medical occurrence in a participant or clinical investigation participant administered a pharmaceutical product, which did not necessarily have a causal relationship with the treatment. TEAEs were AEs with onset dates during the on-treatment period, or the worsening of an event during the on-treatment period. A summary of all Serious Adverse Events and Other Adverse Events (nonserious) regardless of causality is located in the 'Reported Adverse Events' Section.

Time frame: Up to 3 years

Population: Safety Analysis Set: all participants who received at least 1 dose of balstilimab.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Phase 1: Balstilimab Dose 1Phase 2: Number of Participants Experiencing TEAEs161 Participants
Secondary

Phase 2: Number of Participants With Serum ADAs for Balstilimab

Blood samples were collected for serum balstilimab ADA determination.

Time frame: Up to 2.5 years

Population: Safety Analysis Set: all participants who received at least 1 dose of balstilimab.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Phase 1: Balstilimab Dose 1Phase 2: Number of Participants With Serum ADAs for Balstilimab7 Participants
Secondary

Phase 2: ORR as Determined by the Investigator

ORR was defined as percentage of participants with a BOR of CR or PR, as determined by the investigator per RECIST 1.1. BOR was defined as the best response recorded from the start of the study treatment until the end of treatment. CR was defined as disappearance of all target lesions, and PR was defined as at least a 30% decrease in the sum of diameters of target lesions, taking as reference the baseline sum diameters.

Time frame: Up to 3 years

Population: Intent-to-Treat Efficacy Analysis Set: all participants who received ≥1 dose of balstilimab with measurable disease at baseline.

ArmMeasureValue (NUMBER)
Phase 1: Balstilimab Dose 1Phase 2: ORR as Determined by the Investigator14.4 percentage of participants
Secondary

Phase 2: Overall Survival (OS)

OS was defined as time from start of treatment to death. For participants who were still alive at the time of data cutoff for trial analysis or who were lost to follow-up, survival was censored at the last recorded date that the participant was known to have been alive as of the cutoff date for analysis.

Time frame: Up to 3 years

Population: Intent-to-Treat Efficacy Analysis Set: all participants who received ≥1 dose of balstilimab with measurable disease at baseline (per IERC). Here, 'Overall Number of Participants Analyzed' and 'Number Analyzed' signify those participants who were evaluable for this outcome measure.

ArmMeasureValue (MEDIAN)
Phase 1: Balstilimab Dose 1Phase 2: Overall Survival (OS)11.2 months
Secondary

Phase 2: Progression-free Survival (PFS)

PFS was defined as time from first treatment administration to first observation of documented PD (or death within 12 weeks after last tumor assessment), per RECIST 1.1, as determined by an IERC and investigator. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (this included the baseline sum if that is the smallest on study). Participants without an event at analysis cutoff date were censored on date of last tumor assessment.

Time frame: Up to 3 years

Population: Intent-to-Treat Efficacy Analysis Set: all participants who received ≥1 dose of balstilimab with measurable disease at baseline (per IERC). Here, 'Overall Number of Participants Analyzed' and 'Number Analyzed' signify those participants who were evaluable for this outcome measure.

ArmMeasureGroupValue (MEDIAN)
Phase 1: Balstilimab Dose 1Phase 2: Progression-free Survival (PFS)IERC2.8 months
Phase 1: Balstilimab Dose 1Phase 2: Progression-free Survival (PFS)Investigator3.6 months
Secondary

Phase 2: Time to Response (TTR) as Determined by an IERC

TTR was defined as the time from the first dose date to first observation of confirmed response.

Time frame: Up to 3 years

Population: Intent-to-Treat Efficacy Analysis Set: all participants who received ≥1 dose of balstilimab with measurable disease at baseline (per IERC). Here, 'Overall Number of Participants Analyzed' signifies those participants who were evaluable for this outcome measure.

ArmMeasureValue (MEDIAN)
Phase 1: Balstilimab Dose 1Phase 2: Time to Response (TTR) as Determined by an IERC82.0 days
Secondary

Phase 2: Tumor Control Rate (TCR) as Determined by an IERC

TCR was defined as percentage of participants who had a BOR of either SD or a confirmed objective response (CR or PR). CR was defined as disappearance of all target lesions, PR was defined as at least a 30% decrease in the sum of diameters of target lesions, taking as reference the baseline sum diameters. SD was defined as neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for PD, taking as reference the smallest sum diameters while on study. PD was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (this included the baseline sum if that is the smallest on study).

Time frame: Up to 3 years

Population: Intent-to-Treat Efficacy Analysis Set: all participants who received ≥1 dose of balstilimab with measurable disease at baseline (per IERC).

ArmMeasureValue (NUMBER)
Phase 1: Balstilimab Dose 1Phase 2: Tumor Control Rate (TCR) as Determined by an IERC52.5 percentage of participants

Source: ClinicalTrials.gov · Data processed: Feb 28, 2026