Recent Updates
Recently added Catalysts

Botensilimab

Phase 2

Advanced Melanoma | Small molecule | Oncology |Agenus Inc.|Last Updated: Aug 21, 2026

Success Probability

Subscribe to view

Market & Valuation

Subscribe to view

Trial Design

RandomizedCONTROLLED
Total Trials1
Total Enrollment150

FDA Designations

FAST_TRACK

Clinical trial landscape

Botensilimab · 9 trials · 20 indications

Phase 2 7Phase 1 2
NCT07735624RECTIFY-1: Neoadjuvant Botensilimab + Balstilimab in MSS/pMMR Early Rectal CancerEarly Rectal Cancer
RECRUITING16 Analytics
NCT06843551The Miami "EMPIRE" Trial - Eradication of Metastatic Pancreatic Cancer With Immuno-RadiationMetastatic Pancreatic Ductal Adenocarcinoma
RECRUITING20 Analytics
NCT06268015Botensilimab and Balstilimab Optimization in Colorectal CancerColorectal Cancer
ACTIVE NOT_RECRUITING16 Analytics
NCT06279130Pan-tumor Neoadjuvant Basket Study of Immune Check-point Inhibition and Novel Immuno-oncology CombinationsResectable MMR-deficient Solid Tumors
RECRUITING133 Analytics
NCT05630183A Study of Botensilimab in Participants With Metastatic Pancreatic CancerMetastatic Pancreatic Ductal Adenocarcinoma
COMPLETED81 Analytics
NCT05529316A Study of Botensilimab (AGEN1181) for the Treatment of Advanced MelanomaAdvanced Melanoma
ACTIVE NOT_RECRUITING150 Analytics
NCT05608044A Study of Botensilimab and Balstilimab for the Treatment of Colorectal CancerMetastatic Colorectal Cancer
ACTIVE NOT_RECRUITING234 Analytics
PHASE2RECRUITING
RECTIFY-1: Neoadjuvant Botensilimab + Balstilimab in MSS/pMMR Early Rectal Cancer
Early Rectal CancerUnlock trial analytics
PHASE2RECRUITING
The Miami "EMPIRE" Trial - Eradication of Metastatic Pancreatic Cancer With Immuno-Radiation
Metastatic Pancreatic Ductal AdenocarcinomaUnlock trial analytics
PHASE2ACTIVE NOT_RECRUITING
Botensilimab and Balstilimab Optimization in Colorectal Cancer
Colorectal CancerUnlock trial analytics
PHASE2RECRUITING
Pan-tumor Neoadjuvant Basket Study of Immune Check-point Inhibition and Novel Immuno-oncology Combinations
Resectable MMR-deficient Solid TumorsUnlock trial analytics
PHASE2COMPLETED
A Study of Botensilimab in Participants With Metastatic Pancreatic Cancer
Metastatic Pancreatic Ductal AdenocarcinomaUnlock trial analytics
PHASE2ACTIVE NOT_RECRUITING
A Study of Botensilimab (AGEN1181) for the Treatment of Advanced Melanoma
Advanced MelanomaUnlock trial analytics
PHASE2ACTIVE NOT_RECRUITING
A Study of Botensilimab and Balstilimab for the Treatment of Colorectal Cancer
Metastatic Colorectal CancerUnlock trial analytics

Study Endpoints

Primary Endpoints

Complete response (cCR plus nCR with pCR at resection) within 6 months from initiation of therapy or nCR with pathologic complete response (pCR) with TES
From baseline to 6 months from initiation of therapy

Tumor response will be evaluated by a qualified colorectal surgeon using flexible sigmoidoscopy (or equivalent), with biopsy as clinically indicated, and rectal MRI using standard response criteria. Response categories are clinical complete response, near-complete clinical response, no response, or progression. Participants with near-complete clinical response must have pathologic complete response at TES/local excision to meet the endpoint.

Clinical Benefit Rate (CBR)
Up to 15 months

The Clinical Benefit Rate (CBR) among participants will be reported. CBR is the number of participants achieving complete response (CR), partial response (PR) or stable disease after start of study therapy. Response will be assessed using Immune-related Response Evaluation Criteria in Solid Tumors (iRECIST) 1.1 criteria.

Disease control rate based on iRECIST at second restaging scan
24 weeks after screening

Disease control rate is defined as the proportion of subjects who have a complete response, partial response, or stable disease at the time of a second restaging scan. Complete response is defined as disappearance of all target lesions. Partial response is defined as at least a 30% decrease in the sum of diameters of target lesions, taking as reference the baseline sum diameters. Stable disease is defined as a decrease of less than 30% or an increase of less than 20%. Increases of 20% or greater must be confirmed 4-8 weeks later, and confirmation scans must also show an increase of at least 5 mm in the sum of lesion sizes or an increase in the number of lesions. Otherwise, the increase will be counted as stable disease.

Proportion of subjects with a best overall response of complete response or partial response according to iRECIST
up to 2 years

The number of subjects who went on treatment and had a complete response or partial response sometime during the study (prior to progression) divided by the number of subjects who went on treatment.

Major pathological response rate
Week 8

Percentage of patients in which a major pathologic response (MPR) is reported, defined as \<10% residual viable tumor (RVT) in the resection specimen.

Progression-free Survival as Assessed by Investigator
Up to 2 years

Progression-free survival will be defined as the time from the date of randomization to the date of the first objectively documented tumor progression, assessed by investigator per Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1), or death, whichever occurs first.

Objective Response Rate
First dose through up to 3 months

Objective response rate will be determined using Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1).

Maximum Tolerated Dose (MTD)
12 months

To determine the maximum tolerated dose (MTD) of botensilimab when given in combination with balstilimab + triplet chemotherapy regimen (consisting of nab-paclitaxel + gemcitabine + cisplatin) + chloroquine + celecoxib to be used in Part 2-Dose Expansion. MTD will be defined at the dose of botensilimab at which no more than 1 of 6 evaluable patients experiences a dose-limiting toxicity (DLT).

Safety and Tolerability of botensilimab in combination with balstilimab + triplet + chloroquine + celecoxib. Treatment-related toxicities as per National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0 (NCI-CTC AE V5.0).
End of Study (up to 2 years)

To evaluate the safety and tolerability of botensilimab in combination with balstilimab + triplet + chloroquine + celecoxib. Treatment-related toxicities as per National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0 (NCI-CTC AE V5.0).

Incidence Of Treatment-emergent Adverse Events (TEAEs)
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
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
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 Endpoints

Incidence of treatment-emergent adverse events
From first treatment through survival follow-up, up to 5 years from initiation of therapy
Incidence of surgical complications
From surgery through 90-day safety follow-up
Organ preservation rate
From initiation of therapy through post-treatment surgical management decision, approximately 6 months
Unlock Study Endpoints

Study Design & Arms

AllocationNA
MaskingNONE
ModelSINGLE_GROUP
PurposeTREATMENT

Treatment Arms

ArmTypeDescription
Botensilimab + BalstilimabEXPERIMENTALParticipants receive: * Botensilimab: one IV infusion on Cycle 1 Day 1, over about 30 minutes * Balstilimab: IV infusion every 2 weeks on Day 1 of each treatment cycle, over about 30 minutes, for up to 6 months The protocol specifies: * Botensilimab dose: 75 mg IV once * Balstilimab dose: 240 mg IV every 2 weeks for up to 6 months
Radiation, Botensilimab Combined with Balstilimab Treatment GroupEXPERIMENTALParticipants in this group will receive Stereotactic Body Radiation Therapy (SBRT), followed by Botensilimab immunotherapy (ImT) for up to 24 weeks, in combination with Balstilimab ImT for up to one year. Total participation duration is up to five years.
TreatmentEXPERIMENTALbotensilimab + balstilimab until disease progression, then botensilimab + balstilimab + mFOLFOX6 (leucovorin, fluorouracil, oxaliplatin) + {bevacizumab or panitumumab}
Cohort 2: pMMR Safety run-in 1 - closed (accrual reached)EXPERIMENTAL5 Patients will be included and will be treated with 2 cycles of neoadjuvant immunotherapy consisting of 450mg balstilimab and 25mg botensilimab in Cycle 1 and 450mg balstilimab in Cycle 2 followed by surgery Accrual was reached in June 2024, cohort is closed.
Cohort 4: pMMR Safety run-in 2 - closed (accrual reached)EXPERIMENTAL5 Patients will be included and will be treated with 2 cycles of neoadjuvant immunotherapy consisting of 450mg balstilimab and 50mg botensilimab in Cycle 1 and 450mg balstilimab in Cycle 2 followed by surgery Accrual was reached in August 2024, cohort is closed.
Cohort 1: dMMR Safety run-in 1 - closed (accrual reached)EXPERIMENTAL5 Patients will be included and will be treated with 2 cycles of neoadjuvant immunotherapy consisting of 450mg balstilimab and 25mg botensilimab in Cycle 1 and 450mg balstilimab in Cycle 2 followed by surgery Accrual was reached in June 2025, cohort is closed.
Cohort 3: dMMR Safety run-in 2 - closed (accrual reached)EXPERIMENTAL5 Patients will be included and will be treated with 2 cycles of neoadjuvant immunotherapy consisting of 450mg balstilimab and 50mg botensilimab in Cycle 1 and 450mg balstilimab in Cycle 2 followed by surgery Acrrual was reached in August 2024, cohort is closed.
Cohort 6: dMMR Colorectal basket - closed (accrual reached)EXPERIMENTALPatients with resectable colon and rectal cancer will be treated with the regimen assesses as safe and feasible in the dMMR safety run-in. Treatment will be administered at day 1 and day 22 followed by surgery 8 weeks after registration. Accrual will be temporarily halted after accrual of the first 8 patients. If \>2 major pathological responses are observed accrual will continue to a total of 18 patients. Accrual was reached in July 2025, cohort is closed.
Cohort 5: dMMR Upper gastro-intestinal cancer basketEXPERIMENTALPatients with resectable oesophageal (adenocarcinoma), gastro-oesophageal junction, gastric and small bowel cancer will be treated with the regimen assessed as safe and feasible in the dMMR safety run-in. Treatment will be administered at day 1 and day 22 followed by surgery 8 weeks after registration. Accrual will be temporarily halted after accrual of the first 8 patients. If \>2 major pathological responses are observed accrual will continue to a total of 18 patients.
Cohort 7: dMMR "other cancers" basketEXPERIMENTALPatients with resectable solid tumors of various origins such as but not limited to breast-, prostate-, bladder cancer, Head\&Neck SCC, oesophageal SCC and sarcoma will be treated with the regimen assessed as safe and feasible in the dMMR safety run-in. Treatment will be administered at day 1 and day 22 followed by surgery 8 weeks after registration. Accrual will be temporarily halted after accrual of the first 8 patients. If \>2 major pathological responses are observed accrual will continue to a total of 18 patients.
Cohort 8: pMMR TNBC cohortEXPERIMENTALPatients with resectable Triple Negative Breast Cancer will be treated with the regimen assessed as safe and feasible in the pMMR safety run-in. Treatment will be administered at day 1 and day 22 followed by surgery 8 weeks after registration. Accrual will be temporarily halted after accrual of the first 8 patients. If \>2 major pathological responses are observed accrual will continue to a total of 18 patients.
Cohort 9: pMMR "other cancers" - cohort closedEXPERIMENTALPatients with resectable pMMR tumors of various origins will be treated with the regimen assessed as safe and feasible in the pMMR safety run-in. Treatment will be administered at day 1 and day 22 followed by surgery 8 weeks after registration. Accrual will be temporarily halted after accrual of the first 8 patients. If \>2 major pathological responses are observed accrual will continue to a total of 18 patients. Accrual was halted after 8 patients in July 2025, not more then 2 major pathological responses were observed, cohort remains closed.
Cohort 10: pMMR GEA basketEXPERIMENTALPatients with pMMR gastro-, esophageal or GE-junction tumors will receive study treatment that consists of cycle 1) botensilimab 50mg plus balstilimab 240mg 2) FLOT + bal 240mg 3) FLOT plus bot 50mg/bal 240mg 4-5) FLOT + bal 240mg. Surgery will take place a maximum of 6 weeks after start last treatment cycle. Patients will receive 8mg dexamethasone as premedication for docetaxel on the first day of infusion, and no additional doses of dexamethasone are allowed in the following days as an anti-emetic. Post-surgery, patients may receive 4 additional cycles of FLOT according to the standard of care. Evaluation will be performed after the first 3 patients are treated; if the proposed treatment is deemed feasible and all patients received the intended chemotherapy regimen, accrual may continue with the next 3 patients. If the first three patients undergo surgery according to plan without delays that are considered immune-related, accrual may continue beyond six patients (max 21).
Cohort 11: dMMR Rectal Organ Preservation basketEXPERIMENTALPatients with stage I-III dMMR rectal adenocarcinoma who prefer organ preservation are eligible. The study treatment will consist of 1 cycle of combination therapy on day 1: botensilimab 50mg plus balstilimab 450mg, followed by 2 cycles of balstilimab 450mg monotherapy on day 22 and day 43. If at the 1st response evaluation at 10 weeks a limited response, no response or progressive disease is observed, treatment according to standard of care, which may consist of direct surgery or additional neoadjuvant therapy may be considered after discussion in the MDT and with the study team.
Part 1: Combination (Safety Lead-in Phase)EXPERIMENTALParticipants will receive botensilimab in combination with standard-of-care chemotherapy (nab-paclitaxel + gemcitabine).
Part 2: CombinationEXPERIMENTALParticipants will receive botensilimab in combination standard-of-care chemotherapy (nab-paclitaxel + gemcitabine).
Part 2: Standard of CareACTIVE_COMPARATORParticipants will receive standard-of-care chemotherapy (nab-paclitaxel + gemcitabine).
Part 1 Cohort A: BotensilimabEXPERIMENTALParticipants refractory to PD-(L)1 therapy will receive botensilimab intravenously (IV).
Part 1 Cohort B: BotensilimabEXPERIMENTALParticipants refractory to PD-(L)1 and anti-CTLA-4 therapies will receive botensilimab IV.
Part 2 Cohort A: Botensilimab + BalstilimabEXPERIMENTALParticipants refractory to PD-(L)1 will receive botensilimab IV in combination with balstilimab IV.
Part 2 Cohort B: Botensilimab + BalstilimabEXPERIMENTALParticipants refractory to PD-(L)1 and CTLA-4 will receive botensilimab IV in combination with balstilimab IV.
Combination Botensilimab Dose 1 plus BalstilimabEXPERIMENTALParticipants will receive botensilimab at dose 1 given IV and balstilimab given IV.
Combination Botensilimab Dose 2 plus BalstilimabEXPERIMENTALParticipants will receive botensilimab at dose 2 given IV and balstilimab given IV.
Monotherapy Botensilimab Dose 1EXPERIMENTALParticipants will receive botensilimab dose 1 given IV.
Monotherapy Botensilimab Dose 2EXPERIMENTALParticipants will receive botensilimab dose 2 given IV.
Standard of CareACTIVE_COMPARATORParticipants will receive select standard of care as determined by the investigator.
DoseEscalationBotensilimab+balstilimab+nab-paclitaxel+gemcitabine+cisplatin +chloroquine + celecoxibEXPERIMENTALBotensilimab 50 mg IV, Balstilimab 240 mg, nab-paclitaxel 125 mg/m2 + gemcitabine 1000 mg/m2 +cisplatin 25 mg/m2; Chloroquine phosphate 500 mg po (300 mg equivalent chloroquine base); Celecoxib 200 mg po twice daily (BID) on Famotidine 20 mg po BID Aspirin 81 mg
Expansion Cohort-Botensilimab+balstilimab+nab-paclitaxel+gemcitabine+cisplatin+chloroquine+celecoxibEXPERIMENTALBotensilimab (MTD TBD), Balstilimab 240 mg IV, nab-paclitaxel 125 mg/m2 + gemcitabine 1000 mg/m2 +cisplatin 25 mg/m2 IV infusion ; Chloroquine phosphate 500 mg po (300 mg equivalent chloroquine base),Celecoxib 200 mg po twice daily (BID); Famotidine 20 mg po BID Aspirin 81 mg
3-Week MonotherapyEXPERIMENTAL3+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.
6-Week MonotherapyEXPERIMENTAL3+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.
6-Week Combination TherapyEXPERIMENTAL3+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.

Interventions

NameTypeDescription
BotensilimabDRUGone IV infusion on Cycle 1 Day 1, over about 30 minutes
BalstilimabDRUGIV infusion every 2 weeks on Day 1 of each treatment cycle, over about 30 minutes, for up to 6 months
Stereotactic Body Radiation TherapyRADIATIONThe radiation therapy (RT) prescription biologically effective dose (BED10) goal for tumor (α/β=10) aims to achieve at least BED10= 60 Gy for a single fraction plan and at least BED10=100 Gy for a multi-fraction plan. This equates to a prescription dose of at least 20 Gy in a single fraction, 42 Gy over 3 fractions, 50 Gy over 5 fractions, and 62 Gy over 10 fractions. Radiation therapy must be completed for up to 10 daily treatments within a 15-day course.
OxaliplatinDRUG85 mg/m2 IV every 2 weeks
LeucovorinDRUG400 mg/m2 IV every 2 weeks
FluorouracilDRUG400 mg/m2 IV bolus + 2,400 mg/m2 IV (over 46 hours) every 2 weeks
BevacizumabDRUG5 mg/kg IV every 2 weeks
PanitumumabDRUG6 mg/kg IV every 2 weeks
FLOT (Fluorouracil+Leucovorin+Oxaliplatin+Docetaxel)DRUG5-Fluorouracil (2400mg/m2), leucovorin (200mg/m2), oxaliplatin (85mg/m2), docetaxel (50mg/m2).
GemcitabineDRUGStandard-of-care chemotherapy administered intravenously.
Nab-paclitaxelDRUGStandard-of-care chemotherapy administered intravenously.
Standard of CareDRUGRegorafenib or trifluridine and tipiracil.
Chloroquine PhosphateDRUGan antimalarial agent, that is being used in this patient population to sensitize cancer cells to chemotherapy and leads to anticancer effects through inhibiting autophagy
CelecoxibDRUGa second-generation selective Cyclooxygenase 2 (COX-2) inhibitor, is being used in this patient population to enhance the therapeutic effect of cisplatin by inhibiting the expression of COX-2 as well as inhibit anti-apoptotic gene BCL-2 (B-cell lymphoma 2)
Nab paclitaxelDRUGmicrotubule inhibitor indicated for the treatment of Metastatic adenocarcinoma of the pancreas as first-line treatment, in combination with gemcitabine
CisplatinDRUGplatinum-based drug indicated for the treatment of advanced cancers
Unlock Study Design Details

Eligibility Criteria

Age Range18 Years to N/A
SexALL
Healthy VolunteersNo
Study Sites3

Inclusion Criteria: * Histologically confirmed diagnosis of early-rectal cancer clinically staged T1-T2 N0 M0 by MRI (American Joint Committee on Cancer (AJCC) staging 8th edition, 2017). * The tumor must confirmed to be MSS/MMRp by local testing. * The tumor must be evaluable by endoscopy. * Volun...

Countries:United StatesNetherlandsBelgiumBrazilFranceGermanyItalyRussiaSpainSwitzerlandUnited KingdomGeorgia
Unlock Eligibility Criteria

Recent Changes (Last 90 Days)

LOWAug 21, 2026NCT06843551lastUpdatePostDate: changed
LOWAug 21, 2026NCT06843551lastUpdatePostDate: changed
LOWAug 19, 2026NCT07735624Status: NOT_YET_RECRUITING → RECRUITING
LOWAug 19, 2026NCT07735624Status: NOT_YET_RECRUITING → RECRUITING
LOWAug 19, 2026NCT07735624Status: NOT_YET_RECRUITING → RECRUITING
LOWJul 30, 2026NCT07735624NEW_TRIAL: changed
LOWJul 30, 2026NCT07735624NEW_TRIAL: changed
MEDIUMJul 12, 2026NCT05630183TRIAL_REMOVED: changed
MEDIUMJul 12, 2026NCT05630183TRIAL_REMOVED: changed
MEDIUMJul 12, 2026NCT05630183TRIAL_REMOVED: changed
MEDIUMJul 12, 2026NCT05630183TRIAL_REMOVED: changed
HIGHJun 11, 2026NCT05630183Status: ACTIVE_NOT_RECRUITING → COMPLETED
HIGHJun 11, 2026NCT05630183Status: ACTIVE_NOT_RECRUITING → COMPLETED

Frequently asked questions about Botensilimab

What is Botensilimab used for?

Botensilimab is an investigational antibody being studied for the treatment of several cancers, including non-small cell lung cancer, metastatic colorectal cancer, metastatic pancreatic ductal adenocarcinoma, early rectal cancer, and advanced cancer. It is being developed by Agenus Inc. and is currently in Phase 1 clinical trials.

What does Botensilimab target?

Botensilimab is a monoclonal antibody, indicated by its -mab suffix. As an antibody, it is designed to bind to specific targets involved in cancer. However, the specific molecular target has not been disclosed in the available information.

Who makes Botensilimab?

Botensilimab is being developed by Agenus Inc., a biopharmaceutical company. Agenus is publicly traded under the ticker symbol AGEN. The company is conducting clinical trials to evaluate Botensilimab for various oncology indications.

What phase is Botensilimab in?

Botensilimab is currently in Phase 1 clinical development. It has received Fast Track designation from the FDA. Botensilimab is investigational and has not been approved by the FDA for any indication.

What clinical trials is Botensilimab in?

Botensilimab is being studied in several clinical trials, including NCT05529316 for advanced melanoma, NCT05608044 for metastatic colorectal cancer, NCT06076837 for metastatic pancreatic cancer, and NCT06268015 for colorectal cancer. These trials are in Phase 1 or Phase 2 and are active but not recruiting.

Is Botensilimab the same as Botensilimab plus Balstilimab?

Botensilimab is sometimes studied in combination with balstilimab, another investigational antibody. The combination is referred to as Botensilimab plus Balstilimab. Clinical trials such as NCT05608044 and NCT06268015 are evaluating this combination for colorectal cancer.