Pyxis Oncology Unveils Translational Data Supporting Novel ADC MICVO's Triple-Action Mechanism Against Solid Tumors
核心洞察
Pyxis Oncology will present translational data for micvotabart pelidotin (MICVO (搜索)), a first-in-concept extracellular-cleaving ADC targeting extradomain-B of fibronectin (搜索), at ESMO 2025 and AACR-NCI-EORTC conferences.
MICVO (搜索) demonstrates a unique three-pronged mechanism of action including direct tumor cell killing, bystander effect, and immunogenic cell death, distinguishing it from traditional cell surface targeting ADCs.
Clinical data from 37 samples showed reduction in circulating tumor DNA tumor fraction after MICVO (搜索) treatment, particularly in head and neck squamous cell carcinoma at the 5.4 mg/kg dose.
Pyxis Oncology announced it will present comprehensive translational data for micvotabart pelidotin (MICVO (搜索)), a first-in-concept antibody-drug conjugate that employs an extracellular-cleaving mechanism, at two major medical conferences in October 2025. The data will be showcased through two posters at the European Society for Medical Oncology (ESMO) Congress 2025 in Berlin and six posters at the AACR-NCI-EORTC International Conference in Boston.
Novel Mechanism Distinguishes MICVO from Traditional ADCs
MICVO (搜索) represents a paradigm shift in ADC design by targeting extradomain-B of fibronectin (搜索) (EDB+FN (搜索)), a non-cellular structural component of the tumor extracellular matrix, rather than cell surface receptors. This distinctive approach enables the drug to cleave in the extracellular matrix instead of within cells, as occurs with traditional ADCs.
"The data we are presenting at ESMO and AACR-NCI-EORTC add to the growing body of evidence supporting the clinical development of MICVO (搜索), which deploys a distinctive non-cellular targeting strategy with an extracellular-cleaving mechanism that is unique compared to traditional cell surface targeting ADCs that internalize and cleave within the cell," said Lara S. Sullivan, M.D., President, Chief Executive Officer and Chief Medical Officer of Pyxis Oncology.
Triple-Action Anti-Tumor Activity Demonstrated
The translational findings reveal MICVO (搜索)'s potential to exert anti-tumor activity through three distinct mechanisms: direct tumor cell killing, bystander killing, and immunogenic cell death. These mechanisms work synergistically to combat solid tumors while simultaneously remodeling the tumor microenvironment and activating immune responses.
The data highlight MICVO (搜索)'s effects on tumor microenvironment remodeling and immune activation, reinforcing its potential benefit as both monotherapy and in combination with anti-PD1 therapy. This multi-faceted approach distinguishes MICVO from conventional ADCs that primarily rely on direct tumor cell targeting.
Clinical Evidence Supports Molecular Response
Analysis of circulating tumor DNA (ctDNA) tumor fraction from 37 clinical samples demonstrated changes in the vast majority of tested specimens following MICVO (搜索) treatment. Notably, reduction in ctDNA tumor fraction after treatment with MICVO, particularly in head and neck squamous cell carcinoma (HNSCC) and at the 5.4 mg/kg dose, supports a positive molecular response to the therapy.
These findings strengthen the rationale for continued development of MICVO (搜索) in HNSCC at this specific dose in the monotherapy dose expansion study. The molecular response data provides objective evidence of MICVO's therapeutic activity in the clinical setting.
Unique Biomarker Correlations Identified
Features observed in nonclinical samples of the stromal architecture detected using digital pathology may correlate with sensitivity to MICVO (搜索). This finding may be unique compared to tumor cell surface targeting ADCs, attributed to MICVO's targeting of a non-cellular structural component of the extracellular matrix rather than cellular targets.
This biomarker discovery could potentially enable patient selection strategies and optimize treatment outcomes by identifying patients most likely to respond to MICVO (搜索) therapy.
Comprehensive Conference Presentations Planned
At ESMO 2025, Pyxis will present five posters covering histological biomarker analysis, longitudinal ctDNA changes, Phase 1 expansion study details, combination study with pembrolizumab, and first-in-human study results. The presentations will be available as ePosters from October 18-20, 2025, with one oral presentation scheduled for October 19.
The AACR-NCI-EORTC conference will feature six additional posters focusing on target binding properties, immunogenic cell death markers, preclinical combination studies, multiplex immunofluorescence workflows, tumor microenvironment remodeling, and immune response induction. All presentations are scheduled for October 23, 2025.
FDA Fast Track Designation Supports Development
MICVO (搜索) has received Fast Track Designation from the U.S. Food and Drug Administration for treating adult patients with recurrent and metastatic HNSCC whose disease has progressed following treatment with platinum-based chemotherapy and an anti-PD-(L)1 therapy. This designation reflects the significant unmet medical need in this patient population and MICVO's potential to address it.
The company is currently advancing MICVO (搜索) through Phase 1 clinical studies in multiple solid tumor types, with a focused development strategy in HNSCC based on emerging clinical signals. Additionally, Pyxis has initiated a Phase 1/2 combination study evaluating MICVO with pembrolizumab in patients with recurrent and metastatic HNSCC and other advanced solid tumors.