bt7401

BT7401 is a chemically synthesized, multivalent, agonistic bicyclic peptide (Bicycle®) designed as an agonist of CD137 (also known as tumor necrosis factor receptor superfamily member 9 or TNFR9). It is comprised of multiple CD137 monomeric Bicycles connected by stable linkers through a central hinge[2][5]. BT7401 is being developed as an immuno-oncology therapeutic, with preclinical data suggesting it may offer improved anti-tumor activity and a better therapeutic index—potentially with fewer side effects—compared to antibody-based CD137 agonists, which have been limited by toxicity, particularly hepatotoxicity, in clinical trials[2][3][4]. The drug is intended to address the unmet need in patients who no longer respond to checkpoint inhibitors[3][4]. BT7401 leverages Bicycle Therapeutics' proprietary Bicycle platform, which allows for rapid synthesis of stable, high-affinity peptide therapeutics[2][4]. The molecule is fully synthetic and non-antibody-based, potentially offering advantages in safety and manufacturing[2][5].