Icon Genetics has published a milestone paper about the successfully completed pre-clinical evaluation of a novel norovirus vaccine candidate

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.