CytomX Therapeutics to Present CX-801 Phase 1 Monotherapy Biomarker Data at the Society for Immunotherapy of Cancer (SITC) Annual Meeting

Core Insights - CytomX Therapeutics announced initial Phase 1 data for CX-801, indicating activation of tumor-selective interferon signaling in advanced melanoma patients [1][2] - The data supports the ongoing Phase 1 combination study of CX-801 with KEYTRUDA, addressing significant unmet medical needs in melanoma treatment [3] Company Overview - CytomX Therapeutics is a clinical-stage biopharmaceutical company focused on developing conditionally activated, masked biologics for cancer treatment [5] - The company utilizes its PROBODY therapeutic platform to create localized therapies, including CX-801, which is a masked interferon alpha-2b cytokine [5] - CytomX's pipeline includes other candidates like CX-2051, aimed at treating various epithelial cancers [5] Clinical Study Details - Initial biomarker data from the Phase 1 study of CX-801 suggest it induces tumor-localized activation of immune cell populations and interferon-stimulated genes [2] - CX-801 has shown to be generally well tolerated and can modulate the immune tumor microenvironment in patients with metastatic melanoma who are refractory to prior therapies [3] - The poster presentation for CX-801 will take place at the Society for Immunotherapy of Cancer (SITC) Annual Meeting on November 8, 2025 [4]