DX-104 Advances as a Next-Generation OMV Vaccine Candidate

DX-104, a next-generation candidate vaccine generated using Delonix Bioworks’ OMV Plus platform, is poised to become the first gOMV vaccine to enter clinical study in China, with trials planned in China and Australia. The candidate applies a defined combination of edits that have been optimized for MenB, and WuXi Vaccines collaborated with Delonix to scale the DX-104 manufacturing process rapidly to 100 L with high batch-to-batch consistency and full good manufacturing practice readiness.

Outer-membrane vesicles are nonliving, nanosized particles that are released from the outer membranes of Gram-negative bacteria. Preserved outer-membrane antigens, intrinsic innate-immune stimulation, and an acellular safety profile provide a robust biological foundation for modern vaccines. Among the three main categories of OMV-based vaccines, gOMVs stand out for their performance and represent the next logical step in the platform’s evolution.

Since the first OMV vaccine was licensed in 1989 to suppress an epidemic in Cuba, clinical evidence consistently has demonstrated strong safety and immunogenicity, encouraging broad application. Today, OMV-based candidates address many types of pathogens, including shigella, salmonella, pertussis, gonorrhea, and klebsiella bacteria, and even some viral and oncology targets.

Precision strain editing in DX-104 coordinates multigene changes that reduce endotoxic activity, widen strain coverage, raise OMV yield, and preserve and overexpress antigens that are key to protective immunity. This unified architecture displays protective antigens directly on the OMVs, creating potent, self-adjuvanted immunogens without need for detergent extraction, recombinant proteins, or added adjuvants. DX-104 more than triples the protective breadth of a commercially available vaccine, covering 71% of isolates compared with 21%, and also shows much lower reactogenicity.

To support scalable and cost-efficient production, cryogenic transmission electron microscopy and size-exclusion high-performance liquid chromatography confirm uniform vesicle morphology and 98% purity, indicating process robustness. The process is projected to yield over 1 million doses per batch, reducing manufacturing costs and enabling increased access to the product.

The candidate’s rapid advancement highlights how strain-designable vaccine systems are being tuned to specific immune profiles, antigen compositions, and manufacturing requirements. As developers seek technologies that extend antigenic coverage, improve tolerability, and increase manufacturability, OMVs are reemerging as a solution and expanding commercial adoption.