Payload Cassette Technology

  • Payload Cassette Technology

    Our Payload Cassettes enable the rapid release of both multiple and mixed payloads and drive higher concentrations of the payload inside the cell. Payload cassettes can incorporate multiple copies of highly potent toxins (the same kind of toxins typically used in ADCs) or pairs of chemotherapeutic agents in an optimal ratio that work together synergistically to kill cancer cells. This could allow us to improve the Therapeutic Index of widely used chemotherapeutic combination therapies. However, our primary approach to using mixed payloads is to build payload cassettes that use combinations of therapeutic payloads that have been identified to mimic the phenomenon of Synthetic Lethality discussed in Our Development Focus.


  • Mixed Payload Casette_769p

  • We conducted a similar series of validation experiments for a prototype SMDC, BB-03, as we did using BB-01 (see SiLinker Technology section). BB-03 was identical to BB-01 except that it contained a triple payload cassette, i.e. three vinblastine payload molecules for each drug conjugate rather than the single payload per drug conjugate used in BB-01 to validate the correct functioning of the SiLinker itself. Our data demonstrates the potential of the payload concept to synergistically enhance the activity of our TDCs. BB-03 shows essentially complete tumor regression compared to modest tumor growth inhibition by BB-01 at doses that deliver equivalent amounts of payload, as shown below.

    Triple Payload in vivo data_st_769p