Santiago de Compostela, Spain, and Shanghai, China. June 16, 2025.
SunRock Biopharma and Escugen have initiated a strategic collaboration to co-develop SRB123, a first-in-class antibody-drug conjugate (ADC) targeting the CCR9 chemokine receptor (C-C motif chemokine receptor 9), an antigen overexpressed in various solid tumor types such as pancreas, ovary, and lung.
The collaboration combines SunRock’s proprietary antibody SRB1, known for its high affinity and ability to internalize into tumor cells, with Escugen’s EZWi-Fit® linker-payload platform, a next-generation technology for developing anti-drug antibodies (ADCs) optimized for high linker stability and selective payload release within the tumor. The result is a highly differentiated therapeutic candidate specifically designed for solid tumors with high CCR9 expression.
Under the agreement, both companies will share responsibilities during development, file joint patents, and maintain reciprocal licensing option rights. The primary goal is to generate robust preclinical data to support early clinical entry.
“Combining our extensive expertise in antibody engineering with Escugen’s innovative conjugation platform allows us to deliver a precision oncology candidate with the potential to be first-in-class,” said Dr. Laureano Simón, CEO of SunRock. “CCR9 remains an underutilized, yet clinically validated, target. This program addresses unmet medical needs in aggressive tumors with a poor prognosis.”
Dr. Qing Zhou, co-founder and CEO of Escugen, stated: “This strategic collaboration with SunRock Biopharma aligns with our vision to develop first-in-class precision oncology candidates through technological innovation.
Furthermore, it highlights the exceptional advantages of our EZWi-Fit® technology for the development of next-generation ADCs. The potent antitumor activity and favorable safety profile of this platform position it as an effective alternative for solid tumors with high CCR9 expression. We are confident that combining our capabilities will accelerate the development of SRB123 and offer new hope to patients.”
CCR9 has been associated with metastatic potential and chemoresistance, particularly in pancreatic and ovarian cancer. SRB1, SunRock’s proprietary antibody in its unconjugated form, has already demonstrated high preclinical efficacy in these models. The ADC format (SRB123) leverages this effect and enhances tumor cell elimination through the payload delivery system developed by Escugen.
The collaboration will be presented during the BIO International Convention 2025, where both companies will hold meetings with potential partners for development and commercialization.
For more information, please contact: info@sunrockbiopharma.com
