SOUTH SAN FRANCISCO, Calif., April  08, 2024  (GLOBE NEWSWIRE) -- CytomX Therapeutics, Inc. (Nasdaq: CTMX), a leader in the field of conditionally activated, localized biologics, today announced the first patient has been dosed in a Phase 1 dose escalation study (NCT06265688) of CX-2051 in patients with advanced solid tumors. CX-2051 is a masked PROBODY antibody drug conjugate (ADC) directed toward epithelial cell adhesion molecule (EpCAM), a cell-surface target that is highly expressed across many cancer types including colorectal, gastric, endometrial, and ovarian cancers. The cytotoxic payload utilized in CX-2051 is a derivative of camptothecin, a topoisomerase-1 inhibitor, a class of drug that has shown potent clinical anti-cancer activity and demonstrated significant clinical benefit as an approved ADC in multiple cancers. The CX-2051 Phase 1 dose escalation is designed to efficiently test the safety and preliminary anti-tumor activity of CX-2051, to provide initial clinical proof of concept to inform a potential decision to move into dose expansions in 2025.

"EpCAM is a high potential ADC target present at high levels on many solid cancers. CX-2051 has been optimized using our tailored masking strategies and possesses a potent cytotoxic payload ideally suited to specific EpCAM positive tumor types, including colorectal cancer. The successful initiation of the Phase 1 dose escalation study for CX-2051 is an important clinical milestone for CytomX as we continue to advance our multi-modality PROBODY therapeutic pipeline to address areas of significant unmet medical need," said Wayne Chu, M.D., chief medical officer of CytomX Therapeutics.