Vaxiion's Recombinant Bacterial Minicell Platform

Because rBMCs incorporate anything present in the parental bacterial strain with the exception of the chromosome, they can be easily modified to contain molecules produced recombinantly from the parental cells before induction of the rBMC production phenotype. Such molecules include recombinant proteins (including protein toxin payloads and rBMC-surface localized cancer cell targeting molecules), expression plasmids, and various silencing RNA molecules - making for a highly versatile "self assembling" delivery technology.  Adding to these capabilities, Vaxiion's rBMCs can be loaded with high concentrations of small molecule drugs following purification.  

Vaxiion's proprietary bacterial strains are each designed with inducible minicell-production phenotypes to ensure reliable and reproducible  production.

Targeted Drug Delivery using rBMCs

Engineering in specific targeting modalities can be accomplished by a variety of means including the surface expression of recombinant targeting molecules including single chain antibody fragments and bacterial adhesins/invasins. In another approach, Vaxiion has generated an entire rBMC platform system capable of binding and displaying antibodies in the proper orientation by simply mixing rBMCs with the antibody of choice. Covalent attachment methods including chemical cross-linking are also amenable and scalable with rBMCs.   






​​Recombinant bacterial minicells (rBMCs) are small, spherical, bacterial nano-particles (shown at the right are rBMCs budding off of the polar region of a parental E. coli cell, middle panel).  rBMCs are unique in that they contain all of the components of the parental bacteria, except the chromosome. Without chromosomes, rBMCs cannot divide and are non-infectious, making them highly suitable for development as  in vivo targeted delivery products.   

Vaxiion has generated a panel of stable inducible minicell-producing bacterial strains containing key genetic modifications that combine to make manufacturing of our rBMC products reliable, reproducible and scalable. Our proprietary strains are engineered so that they cannot grow outside of the laboratory and production facility yet are capable of generating consistently high yields of rBMCs when grown in permissive conditions, allowing for well-controlled upstream and downstream cGMP production processes. In addition, genetic safeguards that result in the production of immune-attenuated LPS endotoxin component of the rBMC cell wall have been introduced to ensure safety for parenteral use in humans and animals.