On April 17, 2026 Agenus Inc. (Nasdaq: AGEN), a leader in immuno-oncology innovation, reported data from an investigator-initiated Phase II trial at Memorial Sloan Kettering Cancer Center, investigating botensilimab (BOT) and balstilimab (BAL) in combination with agenT-797, MiNK’s allo-iNKT cell therapy, ramucirumab and paclitaxel in patients with advanced PD-1 refractory gastroesophageal adenocarcinoma. The data are being presented at the American Association for Cancer Research (AACR) (Free AACR Whitepaper) Annual Meeting, taking place April 17-22, 2026, in San Diego, CA.

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This Phase II trial, which is the first to combine BOT and BAL with agenT-797 in patients with gastroesophageal cancer who progressed after frontline therapy, was designed to explore the role of immune priming and treatment sequencing. Patients received induction with agenT-797 (alone or plus BOT/BAL) followed by the full combination regimen, or initiated the combination without induction, with longitudinal biomarker sampling throughout. In this study (n=17), the regimen delivered a 77% DCR with long-term survival beyond 20 months in a subset, and the induction arm showed meaningful gains in PFS (6.9 vs. 3.5 months; HR 0.19; p=0.015) and OS (9.5 vs. 5.2 months), with 43% of induction-treated patients alive at both 12 and 18 months—underscoring that durability and survival may be the most clinically relevant endpoints in this PD-1 refractory population.

"These findings illustrate the mechanistic synergy of agenT-797 with botensilimab and balstilimab in this PD-1 refractory setting," said Dhan Chand, Ph.D., Vice President of Research at Agenus. "The induction approach promoted significant intratumoral infiltration of T cells and dendritic cells, the formation of organized tertiary lymphoid structures in on-treatment biopsy tissue from a patient with durable benefit, and activation of peripheral CD4 and CD8 T-cell populations. These changes are consistent with immune priming and tumor immune reprogramming, providing a biological rationale for the improved progression-free survival observed with the induction strategy."

Efficacy findings from the Phase II (n=17) study included:

DCR was observed in 77% of all treated patients, and long-term survival beyond 20 months was seen in a subset
Patients who received induction cycle had longer progression-free survival (PFS) than those treated without induction, with median PFS of 6.9 months versus 3.5 months (HR 0.19; p=0.015), supporting the potential importance of immune priming and treatment sequencing.
Median overall survival (OS) was 9.5 months in the induction cohort versus 5.2 months without induction, with 43% of induction-treated patients alive at both 12 and 18 months, compared with 20% and 0%, respectively, in the non-induction cohort.
The study did not meet its primary endpoint of ORR; however, disease control and longer-term survival observed in a subset of patients support further study of this approach.
Correlative analyses showed that treatment with BOT, BAL, and agenT-797 was associated with significant intratumoral T cell and dendritic cell infiltration, the formation of organized tertiary lymphoid structures in on-treatment biopsies from a patient with prolonged benefit, and activation of peripheral CD4 and CD8 T cells.

The safety profile was consistent with the component agents. The most common treatment-emergent adverse events among all patients included fatigue, fever, diarrhea, anorexia, nausea and mucositis. Immune-related adverse events included dermatitis, colitis, gastritis, enteritis, hepatitis and hypothyroidism.

Additional analysis of the full biospecimen dataset is ongoing and is expected to provide further insight into immune mechanisms, optimal sequencing, and potential biomarkers that could help identify patients most likely to benefit.

Presentation Details:

Abstract Title: A phase II study of agenT-797, botensilimab (BOT) and balstilimab (BAL) in PD-1 refractory gastroesophageal cancer (GEC)
Presenter: Samuel L. Cytryn M.D.; Gastrointestinal Medical Oncologist, Memorial Sloan Kettering Cancer Center
Session Name: Phase II and Phase III Clinical Trials
Date/Time: April 20, 2026 | 2:00–5:00 PM PT; 5:00-8:00 PM EDT
Poster Section: 52
Abstract No.: CT166

(Press release, Agenus, APR 17, 2026, View Source [SID1234664492])

On April 17, 2026 The Parker Institute for Cancer Immunotherapy (PICI), reported that research and expertise from across its network will be showcased at the American Association for Cancer Research (AACR) (Free AACR Whitepaper) Annual Meeting, taking place April 17- 22 in San Diego, California. PICI leaders, investigators, and collaborators are contributing to nearly 100 posters, presentations, and discussions throughout the program – demonstrating the depth and breadth of the network’s contributions to the field of cancer immunotherapy.

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Notably, PICI’s newly appointed Chief of External Affairs Kristen Dahlgren is a co-chair of this year’s Annual Meeting Program Committee. She will also chair an educational session on communicating beyond academic audiences and a forum designed to help attendees gain actionable insights to improve trial efficiency, broaden representation, and enhance the relevance and impact of their research. PICI is also unveiling the latest results from the RADIOHEAD cohort, with the largest plasma proteomics study of its kind for checkpoint inhibitor therapy, alongside new methylation-based tools for monitoring tumor dynamics.

Additionally, Antoni Ribas, Director of the PICI Center at UCLA, will be honored with the 2026 AACR (Free AACR Whitepaper)-Margaret Foti Award for Leadership and Extraordinary Achievements in Cancer Research. This award is presented annually to an individual whose leadership and extraordinary achievements in cancer research have made a major impact in the field.

"Cancer doesn’t wait, and neither do the researchers of the PICI Network. The work our investigators are presenting at AACR (Free AACR Whitepaper) 2026 – across cell therapies, resistance mechanisms, precision platforms and beyond – represents years of collaboration designed to move faster than any single institution could alone," said Dr. Knudsen. "Through our investigators and portfolio companies, we are developing and accelerating access to breakthrough cancer therapies and curating innovation from discovery to commercialization, with the vision of converting all cancers to curable diseases."

Presentation Highlights from the Network

Select highlights from across the network include:

Kristen Dahlgren (PICI): Anatomy lesson: Finding the heart in your science (Saturday, April 18) and How survivor driven priorities can accelerate research innovation (Tuesday, April 21)

Karen Knudsen, MBA, PhD (PICI): Co-author of CBP/p300 and PARP inhibitor combination treatment synergistically enhances anti-tumor efficacy in models of advanced prostate cancer (Abstract 4047)
Oral Presentation, Monday, April 20 (O.I. Richter)
Translational Platforms & Liquid Biopsy

John Connolly, PhD (PICI): High-throughput protein profiling applied to the RADIOHEAD cohort—the largest plasma proteomics study of patients receiving checkpoint inhibitor therapy (Abstract 6332)

Samantha Liang (PICI): Methylation-based tumor fraction monitoring to identify patients who may benefit from comprehensive genomic profiling (Abstract 1122)

Christopher Cabanski (PICI): Hierarchical modeling of methylation-based tumor fraction dynamics for pan-cancer immunotherapy response assessment (Abstract 690)
CAR T & Engineered Cell Therapies

Crystal Mackall, MD (Stanford Medicine): Multiple presentations including IL-18 secreting CAR-T cells for antigen-heterogeneous solid tumors (Abstract 1351); targeting the oncofetal antigen GPC2 in medulloblastoma (Abstract 4009); and a longitudinal single-cell atlas of GD2-CAR T cell therapy in diffuse midline glioma (Abstract 6463)

Carl June, MD (UPenn): Spatial profiling of recurrent glioblastoma in a Phase I CAR T trial (Abstract 3444) and spatial remodeling of the tumor microenvironment by IL-18-armored CD19 CAR T cells (Abstract 6470)

Roddy O’Connor, PhD (UPenn): Metabolic fitness enhancement for CAR-T cells (Abstract 4272) and a novel nanoparticle platform for scalable adoptive immunotherapy manufacturing (Abstract 4291)

Michael Milone, MD, PhD (UPenn): Novel SynKIR-310 platform outperforming CD3-based CAR T in lymphoma models (Abstract 5193)
In Vivo Gene Editing & CRISPR

Alexander Marson, MD, PhD (Gladstone/UCSF): In vivo genome-wide CRISPR screens in human T cells for solid tumor therapy (Abstract 1532); virus-like particle-enabled gene engineering in primary human myeloid cells (Abstract 1580)
Tumor Microenvironment & Resistance

David Barbie, MD (DFCI): Multiple presentations including next-generation immune engagers derived from reprogrammed E. coli (Abstract 4904); co-targeting EZH2 and TEAD in Hippo pathway-mutated cancers (Abstract 1850); and B7-H3 targeting in the SCLC tumor-immune microenvironment (Abstract 5603)

Eli Van Allen, MD (DFCI): Six posters spanning bladder cancer resistance (Abstract 3458), myeloid-driven immunotherapy resistance in prostate cancer bone metastases (Abstract 4084), and tumor mass dormancy in melanoma (Abstract 3450)

Jedd Wolchok, MD, PhD (Weill Cornell Medicine): Tumor IDO1-driven resistance to adoptive cell transfer (Abstract 6537) and clinical strategies to enhance TIL therapy efficacy (Abstract 5624)
Neoantigens & TCR-Based Therapies

Hideho Okada, MD, PhD (UCSF): Splicing-landscape-derived shared neoantigens in IDH-mutant gliomas (Abstract 462) and viral vector vaccination driving brain-resident memory T cells (Abstract 4363)

Christopher Klebanoff, MD (MSK): Immunopeptidomic discovery of fetal WNT-associated antigen NKD1 for HLA-A2-restricted TCR-T therapy in microsatellite-stable metastatic colorectal cancer (Abstract 3714)
Pediatric & CNS Cancers

Robbie Majzner, MD (DFCI): Ganglioside targeting for neuroblastoma (Abstract 7814)

Kai Wucherpfennig, MD, PhD (DFCI): Pre-existing T cells driving durable anti-tumor immunity after oncolytic virus therapy in glioblastoma (Abstract 7743)
Breast Cancer & Solid Tumors

Elizabeth Mittendorf, MD, PhD (DFCI): Age-stratified therapeutic strategies targeting chemoresistance and immunosuppression in triple-negative breast cancer (Abstract 6825)

Lili Yang, PhD (UCLA): Three presentations advancing NKT cell therapy and nanoparticle-mediated disruption of tumor-nerve crosstalk in pancreatic cancer (Abstracts 4316, 153, 6384)

Padmanee Sharma, MD, PhD (MD Anderson): Peripheral immune profiling from the DIET trial in melanoma patients receiving immunotherapy (Abstract 6743)

(Press release, Parker Institute for Cancer Immunotherapy, APR 17, 2026, View Source [SID1234664491])

On April 17, 2026 Precision Biologics, Inc. reported a new target in Acute Myeloid Leukemia (AML) for CAR-NK therapy. Recent data for several human AML subtypes expressing truncated core 1 O-glycans will be presented in a poster at the American Association for Cancer Research (AACR) (Free AACR Whitepaper) Annual Meeting on April 19th, 2026, in San Diego, CA, USA.

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Poster title: NEO-201-recognized truncated Core 1 O-glycans represent a new target for CAR-NK therapy in AML

Presentation of the poster will be made in person on the following date and location:

Sunday, April 19th, 2:00pm – 5:00pm PT

San Diego Convention Center, San Diego, CA, USA

Exhibit Hall

Session Category: Immunology

Session Title: Alternative Cell Type and in Situ Cell Therapies

Location: Poster Section 7

Poster Board Number: 7

Poster Number: 133

Abstract Number: 7933 (published in Cancer Research: View Source)

BACKGROUND:

Acute myeloid leukemia (AML) continues to have poor long-term outcomes, particularly in high-risk and relapsed/refractory disease. Progress in AML immunotherapy has been hindered by the scarcity of antigens selectively expressed on leukemic cells while sparing hematopoietic stem/progenitor cells (HSPCs).

Recent data to be presented for the first time at AACR (Free AACR Whitepaper), clearly identifies truncated Core 1 O-glycans recognized by NEO-201 as a novel AML-associated antigen present across multiple subtypes and largely absent from early hematopoietic progenitors. The potent antileukemic activity of NEO-201CAR NK cells in preclinical systems highlights the promise of this approach and sets the stage for advancing truncated Core 1 O-glycan-directed Cellular therapies into translational and clinical development.

"What was surprising to us was this novel target originally was discovered in solid tumors not healthy tissue, but its expression is also found in hematologic cancers. This provides the basis of targeting this specific glycan when developing cellular therapies for the treatment of refractory leukemias" said Dr. Philip M. Arlen, of Precision Biologics, Inc.

With a 5-year relative survival of only 32.9% from 2015 – 2021, it’s estimated that in the US in 2025 AML claimed about 22,000 new cases, with over 11,000 deaths. (seer.cancer.gov)

(Press release, Precision Biologics, APR 17, 2026, View Source [SID1234664490])

On April 17, 2026 Immunitas Therapeutics ("Immunitas"), a clinical stage precision immunotherapy company committed to discovering and developing novel, antibody-based therapeutics for patients with autoimmune diseases and cancer, reported Phase 1/2a clinical data for IMT-009, its first-in-class anti-CD161 antibody, at the American Association for Cancer Research (AACR) (Free AACR Whitepaper) Annual Meeting 2026, taking place April 17-22 in San Diego, California.

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The presentation, titled "A first-in-human, dose escalation (DE) and biomarker cohort expansion (BCE) of IMT-009 (IMT) in advanced cancer and Phase 1b (Ph1b) combination with fruquintinib (F) in microsatellite stable colorectal cancer (MSS CRC)," highlights Phase 1/2a results supporting continued evaluation of IMT-009 as both a monotherapy and combination treatment for patients with solid tumors and hematologic malignancies.

"These data highlight IMT-009’s potential as a novel immunotherapy with a differentiated mechanism designed to address significant unmet needs across difficult-to-treat cancers," said Amanda Wagner, Chief Executive Officer at Immunitas. "We are particularly encouraged by the early signals of clinical activity and the emerging biomarker insights, which may help guide patient selection and inform future development strategies, both as a monotherapy and in combination."

As of January 30, 2026, 22 patients were treated with IMT-009 monotherapy in the dose-escalation portion of the trial, and 26 patients were enrolled in the biomarker cohort expansion across selected tumor types. IMT-009 is a fully human, Fc-attenuated IgG1 monoclonal antibody that targets CD161, a receptor associated with immune suppression and treatment resistance in cancer. By blocking the CD161-CLEC2D pathway, IMT-009 is designed to enhance anti-tumor immune activity. In the Phase 1b combination arm, 19 patients with second- to fourth-line MSS colorectal cancer received IMT-009 in combination with fruquintinib.

Key findings from the presentation include:

Preliminary anti-tumor activity in heavily pretreated patients: Among patients with MSS colorectal cancer treated with IMT-009 monotherapy at 240 mg or higher, one confirmed partial response was observed, and one additional patient remained on treatment for 14 months with stable disease. In the combination arm, one confirmed partial response was observed, with three additional patients remaining on treatment for more than six months.
Favorable tolerability profile: IMT-009 was generally well tolerated as monotherapy and in combination with fruquintinib. In the monotherapy dose-escalation study, the highest treatment-related adverse event observed was Grade 2. In the combination arm, there was one Grade 4 treatment-emergent adverse event that was not considered related to IMT-009 by the investigator.
Biomarker findings supporting patient selection strategies: Translational analyses suggest that the presence and number of CLEC2D-positive/CD161-positive tertiary lymphoid structures (TLS), as well as CXCL13 expression, may be associated with clinical benefit and could help inform future patient selection approaches.
Presentation Details
Title: A first-in-human, dose escalation (DE) and biomarker cohort expansion (BCE) of IMT-009 (IMT) in advanced cancer and Phase 1b (Ph1b) combination with fruquintinib (F) in microsatellite stable colorectal cancer (MSS CRC)
Presenting Author: Susanna V. Ulahannan, M.D., The University of Oklahoma, Stephenson Cancer Center/SCRI
Abstract Number: CT048
Session: First-in-Human Phase I Clinical Trials
Location: Poster Section 50
Date & Time: Monday, April 20, 2026, 9:00 a.m. – 12:00 p.m. PT

About IMT-009
IMT-009 is a fully human, Fc-attenuated IgG1 monoclonal antibody that binds to CD161 and blocks its interaction with its ligand, CLEC2D. Preclinical data confirm that CD161 blockade with IMT-009 results in enhanced anti-tumor activity. IMT-009 is under evaluation in a Phase 1/2a clinical trial for use as a monotherapy and combination treatment for solid tumor and hematological malignancies. The Phase 1 study is designed to evaluate the safety, tolerability, pharmacodynamic biomarkers, and preliminary efficacy of IMT-009 as well as identify the Recommended Phase 2 Dose (RP2D).

(Press release, Immunitas Therapeutics, APR 17, 2026, View Source [SID1234664489])

On April 17, 2026 Antengene Corporation Limited ("Antengene", SEHK: 6996.HK) , a leading innovative, commercial-stage global biotech company dedicated to discovering, developing and commercializing first-in-class and/or best-in-class medicines for autoimmune disease, solid tumors and hematological malignancies indications, reported that it has released present results from three novel programs in poster presentations at the 2026 American Association for Cancer Research (AACR) (Free AACR Whitepaper) Annual Meeting (AACR 2026). The presentations will feature ATG-125 (B7-H3 x PD-L1 bispecific antibody-drug conjugate [ADC]), an IO + ADC dual-function molecule being developed for the treatment of solid tumors, as well as two investigational T cell engagers (TCEs) developed using the company’s proprietary AnTenGager TCE platform, including ATG-106 (CDH6 x CD3 TCE) for ovarian and kidney cancers, and ATG-112 (ALPPL2 x CD3 TCE) for gynecological tumors, digestive system malignancies, bladder cancer and NSCLC.

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Details of the Poster Presentation:
ATG-125 (B7-H3 x PD-L1 bispecific ADC)
Title: ATG-125, a novel B7H3 x PD-L1 bispecific antibody-drug conjugate, demonstrates potent antitumor efficacy by dual targeting of immune evasion and direct tumor killing
Abstract Number: 5599
Session Category: Immunology
Session Title: T Cell Engagers 2 / Antibody-Drug Conjugates 1
Date: April 21, 2026
Time: 02:00 PM – 05:00 PM (Pacific Time)
05:00 AM, April 22, 2026 – 08:00 AM, April 22, 2026 (Beijing Time)
Location: Poster Section 8

Introduction: B7-H3 and PD-L1 are immune checkpoint molecules broadly overexpressed across multiple solid tumors and are associated with immune evasion and poor prognosis. Although PD-1/PD-L1-directed therapies have demonstrated clinical benefit, treatment resistance remains a significant challenge. B7-H3 is also emerging as a promising ADC target due to its broad tumor expression and rapid internalization. ATG-125 is a novel B7-H3 x PD-L1 bispecific ADC designed to combine direct tumor killing with immune activation by co-targeting two complementary tumor-associated pathways in a single molecule.
Results: ATG-125 bound to both B7-H3 and PD-L1 with high specificity and nanomolar affinity and demonstrated robust antigen-dependent internalization in dual-positive tumor cells, enabling efficient intracellular payload release. The molecule induced tumor cell apoptosis, while its parental naked antibody blocked PD-1/PD-L1 interaction and elicited IL-2 and IFN-γ production in mixed lymphocyte reaction assays. ATG-125 also enhanced T-cell activation, as reflected by an increased ratio of CD69+/CD3+ T cells in co-cultures of tumor cells and human PBMCs. In vivo, ATG-125 demonstrated sustained antitumor activity in HCC827 xenograft models, increased tumor infiltration of CD4+ and CD8+ T cells in PBMC-humanized models, and inhibited tumor growth in a dose-dependent manner in MC38-hB7H3 syngeneic models, accompanied by elevated intratumoral CD8+ T-cell infiltration.
Conclusion: ATG-125 demonstrated synergistic IO+ADC antitumor activity through a differentiated mechanism combining enhanced internalization for payload delivery with the potential to restore anti-tumor immunity. Its compelling preclinical profile supports further development for patients with solid tumors.
ATG-106 (CDH6 x CD3 TCE)
Title: ATG-106, a novel "2+1" format CDH6-targeted T-cell Engager (TCE), shows potent T cell dependent cytotoxicity and in vivo anti-tumor efficacy
Abstract Number: 1621
Session Category: Immunology
Session Title: T Cell Engagers 1
Date: April 20, 2026
Time: 09:00 AM – 12:00 PM (Pacific Time)
00:00 AM, April 21, 2026 – 03:00 AM, April 21, 2026 (Beijing Time)
Location: Poster Section 10

Introduction: CDH6 plays an important role in embryonic kidney development but has negligible expression in adult kidney tissue. Its overexpression in ovarian and renal cancers, together with limited normal tissue expression, makes CDH6 an attractive therapeutic target. However, T cell engagers in solid tumors have often been limited by insufficient efficacy and the risk of cytokine release syndrome. To address these challenges, Antengene developed ATG-106, a novel "2+1", sterically masked CDH6 x CD3 bispecific TCE designed to deliver potent antitumor activity with the potential for a reduced CRS risk profile.
Results: ATG-106 exhibited reduced binding affinity to CD3+ cells before CDH6 crosslinking, while inducing approximately 100- to 400-fold more potent cytotoxicity against CDH6-positive tumor cells compared with a "1+1" CrossMab control TCE. The molecule demonstrated potent T cell-dependent cytotoxicity in ovarian and renal cancer models and showed low immunogenicity risk in vitro. In PBMC-humanized 786-O kidney cancer xenograft models, ATG-106 induced tumor shrinkage in all treated mice, with complete remissions observed in the 0.1 mg/kg and 0.3 mg/kg groups. ATG-106 also induced tumor shrinkage and complete remission in PBMC-humanized OVCAR-3 ovarian cancer models. Notably, pro-inflammatory cytokine levels remained very low in treated animals, suggesting low CRS risk. In non-human primate studies, the surrogate molecule ATG-106-RM was well tolerated at doses up to 10 mg/kg.
Conclusion: ATG-106 demonstrated limited T cell binding in the absence of target cells, potent cytotoxicity against tumor cells, and encouraging in vivo efficacy in ovarian and kidney cancer models. Favorable safety findings with the surrogate molecule in non-human primates further support continued clinical development of ATG-106 as a CDH6-targeted TCE candidate.
ATG-112 (ALPPL2 x CD3 TCE)
Title: ATG-112, a novel ALPP/G x CD3 bispecific T cell engager, for the treatment of ALPP/G+ solid tumors
Abstract Number: 1620
Session Category: Immunology
Session Title: T Cell Engagers 1
Date: April 20, 2026
Time: 09:00 AM – 12:00 PM (Pacific Time)
00:00 AM, April 21, 2026 – 03:00 AM, April 21, 2026 (Beijing Time)
Location: Poster Section 10

Introduction: Placental alkaline phosphatase and related placental-like/germ-cell isoforms, including ALPPL2 and ALPG, are aberrantly expressed in a range of solid tumors while being largely absent from normal adult tissues except the placenta, making them highly promising tumor-selective immunotherapy targets. Antengene developed ATG-112, an ALPP/G x CD3 bispecific TCE based on the AnTenGager platform in a "2+1" format, featuring bivalent antigen binding to improve low-antigen tumor recognition and a sterically masked CD3 binding arm designed to restrict T-cell activation to the tumor microenvironment.
Results: Tissue microarray IHC analysis showed that ALPP/G expression was restricted to placental tissue among normal organs and was not detected in other normal tissues, while frequent expression was observed in endometrial and ovarian cancers, with lower prevalence in bladder, gastric and pancreatic cancers. ATG-112 demonstrated high binding affinity to both ALPP/G-positive tumor cells and recombinant proteins, with EC50 and KD values in the sub-nanomolar range. It induced robust T cell-dependent cytotoxicity against target-positive cells with picomolar EC50 values, while in vitro cytokine-release assays showed minimal cytokine secretion from human PBMCs. In vitro studies also demonstrated that the spatial masking effect of ATG-112 is reversible. Immunogenicity assessment showed low immunogenic potential, and in vivo ATG-112 delivered potent tumor suppression across multiple dose levels in humanized mouse models, with low cytokine release and controllable CRS risk at efficacious doses. The program also demonstrated strong developability characteristics.
Conclusion: ATG-112 demonstrated a compelling preclinical profile, with potent in vitro and in vivo antitumor activity and minimal cytokine release. These findings support the continued advancement of ATG-112 toward clinical development for solid tumors.

(Press release, Antengene, APR 17, 2026, View Source [SID1234664488])