{"doi":"10.1093/infdis/jiab447","title":"Persistence of the Immune Responses and Cross-Neutralizing Activity With Variants of Concern Following 2 Doses of Adjuvanted SCB-2019 Coronavirus Disease 2019 Vaccine","abstract":"<jats:title>Abstract</jats:title>\n               <jats:sec>\n                  <jats:title>Background</jats:title>\n                  <jats:p>We have previously reported the safety and immunogenicity 4 weeks after 2 doses of the Clover coronavirus disease 2019 (COVID-19) vaccine candidate, SCB-2019, a stabilized prefusion form of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein (S-trimer). We now report persistence of antibodies up to 6 months after vaccination, and cross-neutralization titers against 3 variants of concern (VoCs).</jats:p>\n               </jats:sec>\n               <jats:sec>\n                  <jats:title>Methods</jats:title>\n                  <jats:p>In a phase 1 study, adult (18–54 years of age) and elderly (55–75 years of age) volunteers received 2 vaccinations 21 days apart with placebo or 3-, 9-, or 30-µg. We measured immunoglobulin G (IgG) antibodies against SCB-2019, angiotensin-converting enzyme 2 (ACE2) competitive binding antibodies, and neutralizing antibodies against wild-type SARS-CoV-2 (Wuhan-Hu-1) at days 101 and 184, and neutralizing antibodies against 3 VoCs, Alpha (B.1.1.7), Beta (B.1.351), and Gamma (P.1), in day 36 sera.</jats:p>\n               </jats:sec>\n               <jats:sec>\n                  <jats:title>Results</jats:title>\n                  <jats:p>Titers waned from their peak at days 36–50, but SCB-2019 IgG antibodies, ACE2 competitive binding antibodies, and neutralizing antibodies against wild-type SARS-CoV-2 persisted at 25%–35% of their observed peak levels at day 184. Day 36 sera also demonstrated dose-dependent increases in neutralizing titers against the 3 VoCs.</jats:p>\n               </jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions</jats:title>\n                  <jats:p>SCB-2019 dose-dependently induced immune responses against wild-type SARS-CoV-2, which persisted up to day 184. Neutralizing antibodies were cross-reactive against 3 of the most prevalent VoCs.</jats:p>\n               </jats:sec>","journal":"The Journal of Infectious Diseases","year":2021,"id":628925,"datarank":0.44166584687496613,"base_score":2.9444389791664403,"endowment":2.9444389791664403,"self_citation_contribution":0.44166584687496613,"citation_network_contribution":0.0,"self_endowment_contribution":0.44166584687496613,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":18,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1628626,"name":"Lara Hatchuel","orcid":null,"position":1,"is_corresponding":false},{"id":919047,"name":"Filippo Pacciarini","orcid":null,"position":2,"is_corresponding":false},{"id":210078,"name":"Branda Hu","orcid":null,"position":3,"is_corresponding":false},{"id":1522511,"name":"Igor Smolenov","orcid":null,"position":4,"is_corresponding":false},{"id":510566,"name":"Ping Li","orcid":"0000-0001-9893-284X","position":5,"is_corresponding":false},{"id":597371,"name":"Peng Liang","orcid":"0000-0001-9107-6323","position":6,"is_corresponding":false},{"id":1628627,"name":"Htay Htay Han","orcid":null,"position":7,"is_corresponding":false},{"id":1628628,"name":"Joshua Liang","orcid":null,"position":8,"is_corresponding":false},{"id":1593590,"name":"Ralf Clemens","orcid":null,"position":9,"is_corresponding":false},{"id":1628625,"name":"Peter C Richmond","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"Persistence of the Immune Responses and Cross-Neutralizing Activity With Variants of Concern Following 2 Doses of Adjuvanted SCB-2019 Coronavirus Disease 2019 Vaccine","abstract":"<jats:title>Abstract</jats:title>\n               <jats:sec>\n                  <jats:title>Background</jats:title>\n                  <jats:p>We have previously reported the safety and immunogenicity 4 weeks after 2 doses of the Clover coronavirus disease 2019 (COVID-19) vaccine candidate, SCB-2019, a stabilized prefusion form of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein (S-trimer). We now report persistence of antibodies up to 6 months after vaccination, and cross-neutralization titers against 3 variants of concern (VoCs).</jats:p>\n               </jats:sec>\n               <jats:sec>\n                  <jats:title>Methods</jats:title>\n                  <jats:p>In a phase 1 study, adult (18–54 years of age) and elderly (55–75 years of age) volunteers received 2 vaccinations 21 days apart with placebo or 3-, 9-, or 30-µg. We measured immunoglobulin G (IgG) antibodies against SCB-2019, angiotensin-converting enzyme 2 (ACE2) competitive binding antibodies, and neutralizing antibodies against wild-type SARS-CoV-2 (Wuhan-Hu-1) at days 101 and 184, and neutralizing antibodies against 3 VoCs, Alpha (B.1.1.7), Beta (B.1.351), and Gamma (P.1), in day 36 sera.</jats:p>\n               </jats:sec>\n               <jats:sec>\n                  <jats:title>Results</jats:title>\n                  <jats:p>Titers waned from their peak at days 36–50, but SCB-2019 IgG antibodies, ACE2 competitive binding antibodies, and neutralizing antibodies against wild-type SARS-CoV-2 persisted at 25%–35% of their observed peak levels at day 184. Day 36 sera also demonstrated dose-dependent increases in neutralizing titers against the 3 VoCs.</jats:p>\n               </jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions</jats:title>\n                  <jats:p>SCB-2019 dose-dependently induced immune responses against wild-type SARS-CoV-2, which persisted up to day 184. Neutralizing antibodies were cross-reactive against 3 of the most prevalent VoCs.</jats:p>\n               </jats:sec>","is_dataset_classified":null,"base_score":2.9444389791664403,"endowment":2.9444389791664403,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"34480575","pmcid":"PMC8499965","openalex_id":"https://openalex.org/W3196656909","authors":[],"funders":[{"funder_name":"Clover Biopharmaceuticals and the Coalition for Epidemic Preparedness Innovations","grant_id":"RRCL2001","title":null},{"funder_name":"Clover Biopharmaceuticals and the Coalition for Epidemic Preparedness Innovations","grant_id":"RCL2202","title":null}],"total_grants":2,"fwci":1.0531,"citation_percentile":0.80203409,"influential_citations":0,"citation_trend":[{"year":2021,"count":5},{"year":2022,"count":7},{"year":2023,"count":1},{"year":2024,"count":4},{"year":2026,"count":1}],"oa_status":"bronze","license":"https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model","oa_locations":[{"url":"https://academic.oup.com/jid/article-pdf/224/10/1699/41211044/jiab447.pdf","host_type":"journal"},{"url":"https://academic.oup.com/jid/article-pdf/224/10/1699/41211044/jiab447.pdf","host_type":"publisher"},{"url":"http://academic.oup.com/jid/advance-article-pdf/doi/10.1093/infdis/jiab447/40504798/jiab447.pdf","host_type":"publisher"},{"url":"https://doi.org/10.1093/infdis/jiab447","host_type":"journal"},{"url":"https://pubmed.ncbi.nlm.nih.gov/34480575","host_type":"repository"},{"url":"https://www.ncbi.nlm.nih.gov/pmc/articles/8499965","host_type":"repository"},{"url":"https://research-repository.uwa.edu.au/en/publications/bd051693-d011-4361-9451-2aafbedd2c5d","host_type":"repository"},{"url":"http://europepmc.org/pmc/articles/PMC8499965","host_type":"repository"}],"fields_of_study":["SARS-CoV-2 and COVID-19 Research","COVID-19 Clinical Research Studies","Long-Term Effects of COVID-19"],"mesh_terms":["Angiotensin-Converting Enzyme 2","COVID-19","SARS-CoV-2","COVID-19 Vaccines","Adjuvants, Immunologic","Adult","Aged","Antibodies, Viral","Humans","Immunoglobulin G","Immunity","Infant, Newborn","Vaccines, Subunit","Antibodies, Neutralizing","Spike Glycoprotein, Coronavirus"],"keywords":["Persistence (discontinuity)","Coronavirus","Coronavirus disease 2019 (COVID-19)","Immune system","Virology","Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)","Disease","2019-20 coronavirus outbreak","Immunology","Medicine","Infectious disease (medical specialty)","Internal medicine","Outbreak","Vaccine","Immunogenicity","Persistence","Covid-19","Variants Of Concern"],"sdg_mappings":[{"sdg_number":0,"sdg_label":"Good health and well-being"}],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[{"name":"eudract"},{"name":"nct"}],"source":"live","citation_network_status":"fetched"},"created_at":"2026-08-05T15:36:29.258737Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}