García Pérez, JavierPortolés Pérez, AntonioPérez Ingidua, CarlaLora Pablos, DavidGómez De La Cámara, Agustín RamónDíez Fuertes, FranciscoAscaso del Río, Ana2025-01-272025-01-272024-09-20García-Pérez J, Borobia AM, Pérez-Olmeda M, Portoles A, Castaño L, Campins-Artí M, Bertrán MJ, Bermejo M, Arribas JM, López A, Ascaso-del-Rio A, Arana-Arri E, Fuentes Camps I, Vilella A, Cascajero A, García-Morales MT, Castillo de la Osa M, Pérez Ingidua C, Lora D, Jiménez-Santana P, Pino-Rosa S, Gómez de la Cámara A, De La Torre-Tarazona E, Calonge E, Cruces R, Belda-Iniesta C, Alcamí J, Frías J Carcas AJ, Díez-Fuertes F, * and CombiVacS Study Group. Immunogenicity of a third dose with mRNA-vaccines in the ChAdOx1-S/BNT162b2 vaccination regimen against SARS-CoV-2 variants. iScience. 2024 Sep; 27;9:110728. ISSN 2589-0042. https://doi.org/10.1016/j.isci.2024.110728.2589-004210.1016/j.isci.2024.110728https://hdl.handle.net/20.500.14352/116260Summary CombiVacS study has demonstrated a strong immune response of the heterologous ChAdOx1-S/BNT162b2 vaccine combination. The primary outcomes of the study were to assess the humoral immune response against SARS-CoV-2, 28 days after a third dose of a mRNA vaccine, in subjects that received a previous prime-boost scheme with ChAdOx1-S/BNT162b2. Secondary outcomes extended the study to 3 and 6 months. The third vaccine dose of mRNA-1273 in naive participants previously vaccinated with ChAdOx1-S/BNT162b2 regimen reached higher neutralizing antibodies titers against the variants of concern Delta and BA.1 lineage of Omicron compared with those receiving a third dose of BNT162b2 at day 28. These differences between BNT162b2 and mRNA-1273 arms were observed against the ancestral variant G614 at day 90. Suboptimal neutralizing response was observed against BQ.1.1, XBB.1.5/XBB.1.9, and JN.1 in a relevant proportion of individuals 180 days after the third dose, even after asymptomatic Omicron breakthrough infections. EudraCT (2021-001978-37); ClinicalTrials.gov (NCT04860739).engAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/journal articlehttps://doi.org/10.1016/j.isci.2024.110728https://www.sciencedirect.com/science/article/pii/S2589004224019539?via%3Dihubopen access612.017614.2InmunologíaFarmacología (Medicina)Enfermedades infecciosas3202 Epidemiología3212 Salud Publica3209 Farmacología2412 Inmunología