Safety and immunogenicity of SpiN-Tec, a T-cell based RBD-Nucleocapsid chimeric vaccine for COVID-19
The SpiN-Tec MCTI UFMG is a chimeric recombinant protein (SpiN) containing the RBD region from the Spike protein (S) fused with the Nucleocapsid protein (N), adjuvanted with a squalene-based emulsion (CTVad1), which was developed as booster COVID-19 vaccine. This is a phase I clinical trial to evaluate safety and reactogenicity. Thirty-six healthy adults aged 18-54, previously vaccinated with two doses of CoronaVac™ (Sinovac) and a booster with the Comirnaty™ Bivalent BA.4/BA.5 (Pfizer-BioNTech), were randomized to receive either SpiN-Tec (20 μg, 60 μg, or 100 μg) or CoviShield™(AstraZeneca). SpiN-Tec was safe and showed a reactogenic profile comparable to CoviShield. Immunogenicity results showed a dose-dependent increase in IgG levels against N and SpiN, peaking at day 28 post-vaccination and declining by day 180. Neutralizing antibody levels against both the Wuhan ancestral and BA1.88 strains showed similar curves presenting no differences between SpiN-Tec and CoviShield. Importantly, SpiN-Tec induced robust IFN-γ production up to 270 days, particularly by CD4<sup>+</sup> effector memory T cells, indicating a durable immune response memory. These results indicate the potential of SpiN-Tec as a viable COVID-19 booster vaccine.
Authors
- Julia Castro (ORCID: https://orcid.org/0000-0003-2620-328X)
- Luis Adan Flores Andrade (ORCID: https://orcid.org/0000-0003-1601-5816)
- Natália Salazar de Castro (ORCID: https://orcid.org/0000-0002-3857-3723)
- Renata Diniz (ORCID: https://orcid.org/0000-0001-9042-9094)
- Renan P. Souza (ORCID: https://orcid.org/0000-0002-9479-4432)
- Bruno Vinícius Santos Valiate (ORCID: https://orcid.org/0000-0001-6550-7089)
- Karine Lima Lourenço (ORCID: https://orcid.org/0000-0001-6090-4253)
- Isabela Pereira Gomes (ORCID: https://orcid.org/0000-0001-7750-036X)
- Ana Luiza Chaves Maia (ORCID: https://orcid.org/0000-0003-1592-7936)
- Ludmila Bezerra da Silva
- Júlio Castro Alves
- Santuza Maria Ribeiro Teixeira (ORCID: https://orcid.org/0000-0002-2588-2842)
- Flávia Fonseca Bagno (ORCID: https://orcid.org/0000-0003-1578-6678)
- André Bastos Daher (ORCID: https://orcid.org/0000-0002-9747-0222)
- Gregório Guilherme Almeida (ORCID: https://orcid.org/0000-0003-1108-1160)
- Nathália Zini (ORCID: https://orcid.org/0000-0003-1891-1606)
- Helton C. Santiago (ORCID: https://orcid.org/0000-0002-5695-8256)
- Ricardo T. Gazzinelli (ORCID: https://orcid.org/0000-0003-2427-7699)
- Pedro Augusto Alves (ORCID: https://orcid.org/0000-0002-9659-5621)
- Gabriel da Rocha Fernandes (ORCID: https://orcid.org/0000-0002-4897-8521)
- Graziella Gomes Rivelli (ORCID: https://orcid.org/0000-0001-8668-7154)
- J. P. de Souza (ORCID: https://orcid.org/0000-0002-1617-5468)
- Patrícia Machado Pinto (ORCID: https://orcid.org/0000-0003-3545-0039)
- Ana Paula Fernandes (ORCID: https://orcid.org/0000-0001-7085-4202)
- Alex F. Carvalho (ORCID: https://orcid.org/0000-0003-4372-5282)
- Guangzhao Li (ORCID: https://orcid.org/0000-0002-5007-8338)
- Jorge Andrade Pinto
Institutions
- Universidade Federal de Minas Gerais (BR)
- George Washington University (US)
Publication Details
- Journal
- Vaccine
- Published
- 2025-09-22
- DOI
- https://doi.org/10.1016/j.vaccine.2025.127756
- Primary Topic
- SARS-CoV-2 and COVID-19 Research
- Type
- article
- Field-Weighted Citation Impact
- 0.00