VectorBuilder Redefines Plasmid Standards with miniVec

Conventional plasmids as a pharmaceutical material are not only suboptimal in safety and function, but exceedingly costly to produce, prohibitively

VectorBuilder, a global leader in gene delivery technologies and CDMO services, today announced the publication of the miniVec plasmid system, engineered for safer, more efficient, and more scalable development of genetic medicines. The manuscript detailing this breakthrough is now available on BioRxiv.

Plasmids have long been a key material in the manufacturing of biopharmaceuticals, especially genetic medicines such as viral and non-viral vectors used in gene and cell therapies, and mRNA vaccines for COVID-19.

Conventional plasmids are built on a backbone that carries antibiotic-resistance genes to support plasmid proliferation in E. coli host cells. However, these additional genes, unrelated to the intended therapeutic functions of the plasmids, pose safety risks that raise red flags for regulatory authorities, such as the FDA, while reducing manufacturing yield and compromising therapeutic efficacy.

Consequently, conventional plasmids as a pharmaceutical material are not only suboptimal in safety and function, but exceedingly costly to produce, prohibitively so for some therapeutic applications.

The miniVec plasmid system utilizes a miniaturized backbone that removes antibiotic-resistance genes. The result is a plasmid system of greater clinical readiness that is safer and far cheaper to manufacture at scale, while delivering enhanced functionality across diverse applications. For researchers and therapy developers, miniVec provides a new foundation for plasmid design that aligns with the regulatory expectation of “less is more,” positioning it as a new benchmark for how plasmids will be used across the biopharmaceutical industry.

“miniVec represents a foundational shift in plasmid design,” said Dr. Bruce Lahn, Chief Scientist of VectorBuilder. “It establishes a higher baseline for safety, manufacturability, and functionality. From day one, it was designed with the clinic in mind, ensuring that therapy developers and researchers can work with a backbone that aligns with regulatory expectations while enabling budget-friendly manufacturing and superior performance.”

miniVec plasmids carry a miniaturized backbone containing a small RNA that confers constant selective pressure to maintain high plasmid copy numbers in the absence of antibiotics or any other chemical additives during fermentation. Besides avoiding the biosafety concerns and regulatory red flags associated with antibiotics, this design lightens the metabolic load on host cells, which in turn leads to much higher plasmid yield in large-scale fermentation runs.

Furthermore, miniVec plasmids deliver significantly enhanced functionality in a wide range of in vitro and in vivo applications, including transient transfection, electroporation, virus packaging, transposon- and CRISPR-mediated genome integration, and naked DNA vaccination, while showing no detectable immunogenicity or toxicity. For genetic medicine developers, this translates into direct benefits: smoother GMP manufacturing, fewer regulatory hurdles, and dramatic cost savings across the development pipeline.

“miniVec is a direct response to the industry’s demand for plasmids that meet modern expectations,” said Dr. Lahn. “It is not just a major improvement, but a platform designed to advance genetic medicine by making clinical development safer, more efficient, and more cost-effective.”

“As a lab focused on gene delivery development, efficacy and safety concerns, laborious manufacturing protocols, and high-end product costs are some of our major concerns. With miniVec addressing all these key considerations, we could spend less time troubleshooting and more time focusing on the actual questions we want to answer,” said Professor Stephan Matthias at Fred Hutchinson Cancer Center.