ATB Therapeutics described at an antibody engineering conference how its antibody-peptide fusion approach, branded as “atbodies,” is engineered to extend the ADC therapeutic window by targeting off-tumor toxicity constraints. Company co-founder and chief business officer Max Houry said the design uses a peptide linker and enzymatic catalytic payload intended to reduce payload entry into healthy cells, addressing a recurring limitation of traditional ADCs. ATB’s concept contrasts with conventional ADC payloads that often rely on DNA damage or microtubule inhibition; instead, the company is positioning its proprietary enzyme payload as acting on ribosomes. The company also emphasized manufacturing considerations, stating the first question was how to make the platform rather than only proof of activity, and shared in vitro data comparing toxicity profiles between a typical MMAE ADC and an atbody payload approach.