RT023

RT023 is a first-in-class bispecific antibody-drug conjugate (ADC) targeting both Carcinoembryonic Antigen-Related Cell Adhesion Molecule 5 (CEACAM5) and Epidermal Growth Factor Receptor (EGFR). Developed by Shanghai Ruotuo Biosciences, RT023 is designed to address unmet needs in colorectal cancer (CRC), including patients with KRAS mutations or those who have relapsed after EGFR antibody treatment. The molecule consists of a bispecific antibody conjugated to the DNA topoisomerase I inhibitor exatecan via a cleavable linker, maintaining a homogeneous drug-to-antibody ratio (DAR) of 6. Preclinical data indicate that RT023 exhibits high affinity for both targets and a superior internalization rate compared to its parent monospecific antibodies, leading to potent cytotoxicity across a wide range of antigen expression levels. In xenograft models, RT023 demonstrated significant tumor growth inhibition and regression, outperforming existing single-target ADCs and standard therapies.