FIH, Bispecific CD276xCD3 Antibody CC-3 in Patients With Colorectal Cancer

This trial is a first in human (FIH) clinical trial in patients with Colorectal cancer (CRC) after failure of at least three lines of previous therapy aiming to evaluate safety and efficacy of CC-3, a bispecific antibody (bsAb) with CD276xCD3 specificity developed within DKTK. CC-3 binds to CD276 on cancer cells as well as to tumor vessels of CRC, thereby allowing for a dual mode of anti-cancer action. CC-3 was developed in a novel format which not only prolongs serum half-life, but most importantly reduces off-target T cell activation with expected fewer side effects. A similar construct in this format with PSMAxCD3 specificity is presently undergoing clinical evaluation in patients with prostate cancer (NCT04104607), with very favorable safety and preliminary efficacy. The optimized format that CC-3 shares with its PSMAxCD3 "sister molecule" allows for application of effective bsAb doses with expected high anticancer activity. The clinical trial comprises two phases: The first phase is a dose-escalation part to evaluate the maximally tolerated dose (MTD) of CC-3. This is followed by a dose-expansion part to defined the recommended phase II dose. A translational research program comprising, among others, analysis of CC-3 half-life and the induced immune response will serve to better define the mode of action of CC-3.