Enesi Pharma’s ImplaVax®-Enabled, Solid-Dose Modified Live Virus Vaccine Produces Neutralising Antibody and T-Cell Responses Equivalent to Liquid Vaccine Delivered via Needle and Syringe

  • Study investigating potential of solid-dose vaccine for porcine reproductive and respiratory syndrome virus (PRRSV) conducted in collaboration with The Pirbright Institute
  • Positive top-line results demonstrate validation of ImplaVax®-enabled solid-dose vaccination approach with a live virus vaccine

OXFORD, UK – 29 September 2020 – Enesi Pharma (“Enesi”), an innovative biotechnology company developing next-generation vaccination products targeting infectious diseases and emergent threat pathogens enabled by its ImplaVax® technologies, is delighted to report positive top-line results from a new study evaluating the immune responses generated by an ImplaVax®-enabled unit solid-dose formulation of a live attenuated porcine reproductive and respiratory syndrome virus (PRRSV) vaccine. The study was conducted in collaboration with The Pirbright Institute, a UK-based global centre of excellence in research and surveillance of viral diseases of livestock and viruses that spread from animals to humans.

The study confirmed the utility of ImplaVax® to create a solid-dose live virus vaccine that is immunogenic with the potential for enhanced thermal stability. The subcutaneously delivered ImplaVax® format generated both neutralising antibodies and T-cell responses comparable to the standard liquid vaccine delivered either subcutaneously or intramuscularly via needle and syringe.

PRRSV infects domestic pigs and causes porcine reproductive and respiratory syndrome, which is highly infectious and is characterised by clinical signs such as reproductive failure, fever, respiratory difficulties and increased mortality. PRRSV is found in most areas of the world where pigs are raised and is one of the most economically important diseases for the global pig industry, with losses estimated to exceed $664 million annually in the USA alone1.

More details of the study and its results will be presented in an upcoming publication.

David Hipkiss, Enesi Pharma CEO, commented:

“We are very pleased to report these positive top-line results from this successful study conducted in partnership with The Pirbright Institute, which has proven to be an exemplar collaborator. They provide a strong and clear validation for the potential of ImplaVax® as applied to modified live virus vaccines across the whole of the vaccine ecosystem. We believe there is significant opportunity for Enesi and ImplaVax® in the growing animal health market, which is forecast to exceed $16 billion per annum by 20262. Both livestock and companion animals need to be continually protected from infectious diseases, and ImplaVax® offers a needle-free, thermally stable, safe and effective means of administration. The implications for our ongoing work with modified live virus vaccines for human health are also very exciting and we look forward to reporting on further progress from our partnered and in-house programmes.”

Professor Simon Graham, Group Leader of the Porcine Reproductive and Respiratory Syndrome (PRRS) Immunology Group at The Pirbright Institute, added:

“PRRSV is a significant animal health concern given the importance of pigs globally as a livestock animal. The work we are doing at Pirbright and in collaboration with innovative companies such as Enesi Pharma is crucially important to maintaining and improving the health and wellbeing of farm animals. The positive results of this new study with Enesi point to an alternative approach to vaccination that combines effectiveness with the potential for improved stability. This could be of great value to the industry and we look forward to continuing this research collaboration.”


1 Holtkamp D.J., et al, J Swine Health Prod. 2013;21(2):72-84

2 https://www.fortunebusinessinsights.com/industry-reports/veterinary-animal-vaccines-market-101532