Rift valley academy paual denmark trial#

Rift valley academy paual denmark trial#

Methods: A phase I first-in-human dose-ranging trial of a saRNA COVID-19 vaccine candidate LNP-nCoVsaRNA, was conducted at Imperial Clinical Research Facility, and participating centres in London, UK, between 19th June to 28th October 2020. Participants received two intramuscular (IM) injections of LNP-nCoVsaRNA at six different dose levels, 0.1-10.0μg, given four weeks apart. Libri V, Boffito M, Owen D, Bern H, O'Hara J, McFarlane LR, Lemm N-M, McKay PF, Rampling T, Yim YTN, Milinkovic A, Kingsley C, Cole T, Fagerbrink S, Aban M, Tanaka M, Mehdipour S, Robbins A, Budd W, Faust SN, Hassanin H, Cosgrove CA, Winston A, Fidler S, Dunn DT, McCormack S, Shattock RJ, COVAC1 study Group et al., 2022, Safety and immunogenicity of a self-amplifying RNA vaccine against COVID-19: COVAC1, a phase I, dose-ranging trial, EClinicalMedicine, Vol: 44, ISSN: 2589-5370īackground: Lipid nanoparticle (LNP) encapsulated self-amplifying RNA (saRNA) is a novel technology formulated as a low dose vaccine against COVID-19. In contrast, repeated exposure to antigenically distinct spikes, via infection and or vaccination drives a more cross-reactive immune response, both in hamsters and people.One Sentence SummaryInfection with the Delta and Omicron SARS-CoV-2 vari To conclude, cohorts whose only immune experience of COVID is Omicron/BA.1 infection may be particularly vulnerable to future circulation of Delta or Delta-like derivatives. Prior vaccination followed by Omicron or Delta breakthrough infection led to a higher degree of cross-reactivity to all tested variants. Indeed, cross-neutralisation assays with human antisera from otherwise immunonaïve individuals (unvaccinated and no known prior infection), confirmed a large antigenic distance between Delta and Omicron. Omicron/BA.1 was protective against Omicron/BA.2, but not Delta reinfection, again showing Delta and Omicron have a very large antigenic distance.

We further tested whether prior infection with Omicron/BA.1 protected from re-infection with Delta or Omicron/BA.2. Prior infection with ancestral or Alpha variant was partially protective against Omicron/BA.1 infection, whereas all animals previously infected with Delta and exposed to Omicron became infected, although shed less virus. We found that 2-doses of self-amplifying RNA vaccine based on the ancestral spike ameliorated weight loss following Delta infection and decreased viral loads, but had minimal effect on Omicron/BA.1 infection. Here we describe a hamster contact exposure challenge model to assess protection conferred by vaccination or prior infection against re-infection. Kurshan A, Yau Y, Lechmere T, Brown JC, Moshe M, Kugasathan R, Snell LB, Edgeworth JD, Shattock RJ, Doores KJ, Peacock TP, Barclay WS et al., 2022, Omicron breakthrough infections in vaccinated or previously infected hamstersĪbstractThe second and third years of the SARS-CoV-2 pandemic have been marked by the repeated emergence and replacement of ‘variants’ with genetic and phenotypic distance from the ancestral strains, the most recent examples being Delta and Omicron.