Bioconjugation Technology

This technology utilizes an in vivo enzyme-based bioconjugation method that alleviates the challenges associated with a chemical conjugation process. At the core of this approach is a bacterial enzyme capable of forming precise linkages between a surface glycan from a pathogen and an immunogenic protein. This approach reduces development timelines, increases cost-effectiveness, and enhances safety compared to traditional processes.

Since 2015, LimmaTech has had an exclusive research and development agreement with GSK, which acquired the bioconjugation technology from LimmaTech’s predecessor, GlycoVaxyn. Currently, LimmaTech is evaluating three vaccine development programs in clinic trials using this technology, including LimmaTech’s vaccine candidate against Shigella (S4V) exclusively licensed from GSK, a GSK-owned vaccine candidate against Klebsiella, and one yet-to-be disclosed program.

Shigella4V (S4V)

  • Composition: Shigella4V is a tetravalent bioconjugate vaccine encompassing the O-antigen polysaccharides of S. flexneri 2a, 3a, 6, and S. sonnei
  • Global Impact: Vaccine candidate targets the four predominant pathogenic Shigella serotypes responsible for up to 85% of global infections

LimmaTech has in-licensed this Shigella bioconjugate vaccine from GlaxoSmithKline (GSK) to advance its clinical development. The vaccine candidate is currently being evaluated in a Phase I/II clinical trial.

Toxoid Vaccine Technology

This technology is designed to contain forms of the pathogen’s toxins with suppressed toxicity, referred to as toxoids, that the pathogen would normally secrete to cause an infection. This strategy, involving a toxoid formulation, has benefits over targeting molecules on the pathogen’s surface in specific cases, such as for S. aureus. The toxoid vaccine approach mitigates the risk of deleterious immune responses often associated with surface-targeted vaccines.

LimmaTech has in-licensed a toxoid vaccine candidate, LBT-SA7 (formerly IBT-V02), from AbVacc to prevent reinfections caused by the bacterial pathogen Staphylococcus aureus. The program is currently Phase I-ready and expected to enter clinical studies in 2024.


  • Composition: LBT-SA7 is a rationally designed multivalent toxoid vaccine comprised of multiple toxoids that are involved in a Staphylococcus aureus (S. aureus) infection and has the potential to elicit an immune response against the pathogen’s original toxins.
  • Global Impact: Vaccine could be used for community-associated and hospital-acquired infections, which account for the majority of antimicrobial-resistant cases