Halle (Saale), 11. February 2022. Icon Genetics GmbH, a wholly owned subsidiary of Denka Co. Ltd, Tokyo, Japan, has successfully completed pre-clinical evaluation of its norovirus vaccine candidate supporting clinical testing in humans and published a milestone paper in the renowned journal “Vaccine”.
Noroviruses are responsible for approximately 20% of all cases of acute gastroenteritis worldwide. Despite decades of intensive research in the field, no licensed vaccine for preventing norovirus disease and ameliorating detrimental health, societal, and economic effects in all age groups is available today. Therefore, its is generally recognized that development of an efficacious vaccine against norovirus gastroenteritis is of paramount importance given its potential to reduce the global burden of norovirus-associated morbidity and mortality.
The pre-clinical evaluation on the safety and immunogenicity was conducted for the plant-made vaccine candidate composed of two virus-like particles (VLPs) derived from human norovirus genogroups I and II, which are responsible for most of the norovirus outbreaks. The evaluation encompassed three animal studies in rabbits, where the vaccine was administered by intramuscular (IM) or subcutaneous (SC) injection, either with or without adjuvant. The results showed that the vaccine was well tolerated and did not cause any systemic toxicity or adverse effects. The vaccine also elicited strong immune responses against both VLPs even without adjuvant. In conclusion, the obtained results showed that the plant-made norovirus vaccine candidate is safe and immunogenic and fully supported the initiation of clinical development in humans.
For its candidate norovirus vaccine Icon Genetics produces norovirus-like particles (VLPs), that mimic the structure of the virus but are not infective, in high yield using the company’s magnICON® technology. The proprietary magnICON® technology utilizes tobacco plants for the rapid, scalable, and environment-friendly production of diverse recombinant proteins to serve the diagnostics and biopharmaceuticals markets. Unlike with older GMO technologies, Icon Genetics’ production host plants are not genetically modified in a stable manner but are rather temporarily instructed to produce a protein of interest by treatment with a bacterial vector carrying the genetic blueprint for the product. The target proteins are produced indoors and are subsequently extracted in pure form from the plants’ leaves. The norovirus vaccine candidate was produced at Icon Genetics’ pilot-scale facility in Halle/Saale, Germany.