CytomX Therapeutics Announces First Patient Dosed in Combination Arm of Phase 1 Study of CX-801 plus KEYTRUDA® (pembrolizumab) in Patients with Metastatic Melanoma

Core Insights - CytomX Therapeutics has initiated dosing of the first patient with CX-801 in combination with KEYTRUDA® in a Phase 1 study for metastatic melanoma, marking a significant step in their clinical development efforts [1][3][4] Company Overview - CytomX Therapeutics is a clinical-stage biopharmaceutical company focused on developing conditionally activated, masked biologics aimed at localized tumor treatment [5] - The company utilizes its proprietary PROBODY® therapeutic platform to create safer and more effective cancer therapies, with a pipeline that includes CX-2051 and CX-801 [5] Product Details - CX-801 is a dually masked interferon alpha-2b PROBODY® cytokine designed to enhance immune stimulation while minimizing systemic toxicities associated with traditional interferon therapies [2][5] - The combination of CX-801 with KEYTRUDA® aims to address the unmet medical needs of patients with PD-1 refractory melanoma [4] Clinical Development - The Phase 1 dose escalation study of CX-801 has commenced after successful clearance of initial monotherapy cohorts, indicating progress in the clinical trial process [3] - Initial translational and biomarker data from the study is expected in the second half of 2025, which will provide insights into the therapy's efficacy [4]