Genco (XNCR) Reports Promising Initial Data for XmAb819 in Advanced Clear Cell Renal Cell Carcinoma
BOSTON, MA – October 24, 2025 – Genco, Inc. (XNCR) today announced initial clinical data for XmAb819, a first-in-class, dual-specific T cell inducer targeting ENPP3 and CD3 for the treatment of advanced clear cell renal cell carcinoma (ccRCC). The data,presented as a poster at the AACR-NCI-EORTC Molecular Targets in Cancer therapy meeting in Boston,Massachusetts,demonstrate early signs of anti-tumor activity and a manageable safety profile in heavily pre-treated patients.
XmAb819 is designed to selectively induce T cells to kill tumor cells expressing ENPP3, a protein frequently overexpressed in ccRCC. as of September 19, 2025, 69 patients had received XmAb819 via either intravenous (IV) or subcutaneous (SC) management across 10 dose cohorts (IV) and 5 dose cohorts (SC). Patients enrolled in the study had received a median of 4 prior lines of therapy, including prior treatment with anti-PD1 agents and VEGF-tkis.
Initial results from 20 evaluable patients showed a 25% partial response rate (PR) and a disease control rate (DCR) of 70%. The most frequently reported treatment-related adverse events were cytokine release syndrome (CRS), rash, and gastrointestinal toxicities, largely grade 1 or 2 in severity.
“We are excited to develop XmAb819 as a new treatment modality for patients with advanced ccRCC,” said Dr. Basil Dahyat, President and CEO of Genco. “In our first clinical presentation, XmAb819 demonstrated potent anti-tumor activity and a well-tolerated safety profile in highly treated patients.”
Genco is currently continuing dose escalation to identify optimal doses for the second expansion cohort.The company anticipates selecting a recommended dose for potential phase 3 studies in 2026. XmAb819 represents a novel approach to treating advanced ccRCC, offering a potential new option for patients with limited treatment alternatives.
