Molecular Templates has developed a new class of targeted biological therapeutics with unique functional properties by proprietarily modifying a bacterial toxin to reduce its immunogenicity and allow for its PEGylation. This bacterial toxin scaffold has been fused to randomized scFv fragments and expressed on phage display to create screenable libraries of next generation immunotoxins called Engineered Toxin Bodies (ETBs). These ETBs retain the parent toxin's ability to force internalization, route through the cell in an anticipatory manner, and enzymatically and irreversibly inhibit ribosome activity. Because of PEGylation, ETBs have an improved and predictable pharmacokinetic and ADME profile with reduced non-specific toxicity and immunogencitiy.
Forced receptor internalization - Extracellular proteins which previously did not internalize efficiently can now be used as targets based on the ability of ETBs to force cell entry
Intracellular routing - ETBs can be targeted to cells with specific extracellular markers and then used to deliver various payloads to different compartments of the cell
Ribosome inactivation - The irreversible, enzymatic mechanism of cell kill is unique in oncology. Ribosome inactivation can be eliminated by mutations in the ETB that preserve internalization and routing