Agenus Publishes Seminal Study on Botensilimab’s Activity in Treatment-Resistant Cancers

Agenus Inc. (NASDAQ: AGEN), a leader in developing novel immunological agents to treat various cancers, today announced the publication of a seminal study in the prestigious Cancer Discovery, a journal of the American Association for Cancer Research, detailing the novel mechanism of action and effectiveness of botensilimab, an investigational, novel multifunctional anti-CTLA-4 antibody, in various treatment-resistant cancers.

The paper, entitled “Botensilimab, an Fc-Enhanced Anti-CTLA-4 Antibody, Is Effective Against Tumors Poorly Responsive to Conventional Immunotherapy,” highlights several key findings:

1. Demonstrated Activity Across Multiple Cancers: Botensilimab has shown increased activity in multiple treatment-resistant cancers, including those that have progressed on prior checkpoint inhibitors.
2. Fc-Enhanced Design for Multifunctional Immune Activation: Unlike traditional anti-CTLA-4 antibodies, botensilimab’s Fc-enhanced design allows it to leverage multiple immune-activating mechanisms simultaneously. This includes enhanced T cell priming, reduction of intratumoral regulatory T cells, and activation of antigen-presenting cells, leading to a robust anti-tumor response.
3. Activity Independent of Conventional Limitations: Botensilimab shows clinical activity regardless of factors that typically limit conventional immunotherapy efficacy, such as tumor neoantigen burden and FcγRIIIA genotype. This broadens its potential applicability across diverse patient populations.
4. Remodeling the Tumor Microenvironment: The antibody uniquely remodels the tumor microenvironment, transforming "cold" tumors that are currently unresponsive to immune therapies into "hot" immunologically active tumors. This is achieved by reducing regulatory T cells and increasing T cell inflammation gene signatures within the tumor microenvironment.
5. Promise in Difficult-to-Treat Cancers: Botensilimab demonstrates significant promise in treating over nine difficult-to-treat cancers, including microsatellite stable colorectal cancer and may extend clinical benefits to patient populations historically unresponsive to conventional immune checkpoint inhibitors.

“We are thrilled to share these groundbreaking findings with the scientific community,” said Dhan Chand, PhD, lead author and Vice President of Research at Agenus. “The compelling preclinical and clinical evidence generated with botensilimab reveal an actionable pathway to improve treatment outcomes and extend survival to patient populations historically unresponsive to conventional immune checkpoint inhibitors.”