학술논문

Effectiveness, safety, and immunogenicity of half dose ChAdOx1 nCoV-19 COVID-19 Vaccine: Viana project
Document Type
article
Author
Valéria ValimOlindo Assis Martins-FilhoMaria da Penha Gomes GouveaLuiz Antônio Bastos CamachoDaniel Antunes Maciel VillelaSheila Maria Barbosa de LimaAdriana Souza AzevedoLauro Ferreira Pinto NetoCarla Magda Allan Santos DominguesNésio Fernandes de Medeiros JuniorIsac Ribeiro MoulazLaiza Hombre DiasSamira Tatiyama MiyamotoAndréa Teixeira-CarvalhoJosé Geraldo MillHalf Dose ChAdOx Study GroupThayná Martins GouveiaBeatriz Paoli ThompsonKaren Evelin Monlevade LançaGabriela Curto Cristianes LacerdaJoão Pedro Gonçalves LenziSabrina de Souza RamosFelipe de Castro PimentelLudimila ForechiThaís RuchdeschelJoão Pedro Moraes MiossiMatheus Leite RasseleGabriel Smith Sobral VieiraLaís PastiAllan Gonçalves HenriquesMaria Eduarda Morais Hibner AmaralAlessandro Demoner RamosHeitor Filipe SurloLaura Gonçalves Rodrigues AguiarLuiza Lorenzoni GrilloMatheus PereiraRamon Borge RizziSara Monteiro MunizHully Cantão dos SantosThais Luma de Oliveira RozaAdriana Santos SilvaLunara Baptista FerreiraKarina LallemandKetty Lysie Libardi Lira MachadoTania Queiroz Reuter MottaJaquelini JubiniCarla Cristina Moraes de MattosMaria Angélica Calegário VieiraDanielle Grillo Pacheco LyraCristiano Soares da SilvaRodrigo Ribeiro RodriguesLuís Carlos ReblinOrlei CardosoLely Stella Guzmán BarreraJhader PércioIsmael Artur da Costa RochaRoberta Oliveira PradoAgnes Antônia Sampaio PereiraVitor Hugo Simões MirandaGláucia Diniz AlessioFernanda Fortes de AraújoElaine SpezialiChristiane Costa PereiraClarice Carvalho AlvesKétyllen Reis Andrade de CarvalhoAnna Carolina Cançado FigueiredoLiliane Martins dos SantosCristiana Couto GarciaNani Oliveira CarvalhoLaise Rodrigues ReisTâmilla Mayane Alves Fidelis dos SantosJoaquim Pedro Brito-de-SouzaCamila Medeiros CostaIsabela Natália Pascoal Campos do ValePriscilla Miranda HenriquesPoliane Silva MacielThais Abdala TorresNathália Werneck Cézar de OliveiraGabriela de OliveiraLuana Oliveira Borges FernandesAndreza Parreiras GonçalvesJesuanne Carla Silva AndradeLadson Lúcio Viana da SilvaArmanda Moreira Mattoso BarbosaMaria Beatriz Martins AraújoBruna Luiza Fonte Boa RochaLis Ribeiro do Valle AntonelliAna Carolina Campi-AzevedoVanessa Peruhype-MagalhãesWaleska Dias SchwarczNathalia dos Santos AlvesIngrid Siciliano HorbachAriane Faria de SouzaBrenda de Moura DiasBruno Pimenta SetatinoCaio Bidueira Denani
Source
Frontiers in Immunology, Vol 13 (2022)
Subject
COVID-19
fractional dose
ChAdOx1
effectiveness
immunogenicity
vaccine
Immunologic diseases. Allergy
RC581-607
Language
English
ISSN
1664-3224
Abstract
Fractional dose is an important strategy to increase access to vaccines. This study evaluated the effectiveness, safety, and immunogenicity of half dose of ChAdOx1 nCoV-19 vaccine. A non-inferiority non-randomized controlled trial compared a half dose of ChAdOx1 nCoV-19 with the full dose, with an interval of 8 to 10 weeks, in individuals aged 18–49 years. The primary endpoints were the incidence rate of new cases/1,000 person-year at 90 days after 14 days of the second dose, confirmed by RT-PCR and new cases registered at SUS National Health Surveillance Database (e-SUS VS). The anti-SARS-CoV-2 spike (S) protein receptor binding domain (RBD) by chemiluminescence and the neutralizing antibodies by plaque reduction neutralization test (PRNT) were titrated. The soluble biomarkers were quantified with a multiplex immunoassay. Follow-up was 90 days after 14 days of the second dose. A total of 29,598 individuals were vaccinated. After exclusion, 16,570 individuals who received half a dose and 6,402 who received full doses were analyzed. The incidence of new cases confirmed by RT-PCR of half dose was non-inferior to full dose (23.7 vs. 25.7 cases per 1,000 persons-year [coefficient group -0.09 CI95%(-0.49 to 0.31)], even after adjusting for age and sex. There were no deaths or hospitalization after immunization of either group. Immunogenicity was evaluated in a subsample (N=558) compared to 154 healthcare workers who received a full dose. The seroconversion rate in seronegative individuals at baseline half dose was 99.8%, similar to that of the full dose (100%). Geometric mean concentration (95% CI; BAU/mL) were half dose = 188 (163-217) and full dose = 529 (423–663) (p < 0.001). In seropositive subjects at baseline (pre-immune individuals), the first dose induced very high and similar IgG-S in half dose 1,359 (1,245-1,483) and full dose 1,354 (1,048–1,749) BAU/mL. A half dose induced a high increase in plasma chemokines, pro-inflammatory/regulatory cytokines, and growth factors. The frequency of adverse events was similar. No serious adverse events or deaths were reported. A half dose of ChAdOx1 nCoV-19 is as effective, safe, and immunogenic as the full dose. The immune response in pre-immune (seropositive in the baseline) individuals indicates that the half dose may be a booster dose schedule.