{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:14:52Z","timestamp":1792790092394,"version":"4.5.0"},"reference-count":21,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,8,21]],"date-time":"2025-08-21T00:00:00Z","timestamp":1755734400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Major Scientific and Technological Special Project for \u201cProgram of Significant New Drug Developments\u201d","award":["2013ZX09102041"],"award-info":[{"award-number":["2013ZX09102041"]}]},{"name":"National Major Scientific and Technological Special Project for \u201cProgram of Significant New Drug Developments\u201d","award":["81991492"],"award-info":[{"award-number":["81991492"]}]},{"name":"National Major Scientific and Technological Special Project for \u201cProgram of Significant New Drug Developments\u201d","award":["82041039"],"award-info":[{"award-number":["82041039"]}]},{"name":"National Major Scientific and Technological Special Project for \u201cProgram of Significant New Drug Developments\u201d","award":["2021YFC2302604"],"award-info":[{"award-number":["2021YFC2302604"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2013ZX09102041"],"award-info":[{"award-number":["2013ZX09102041"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["81991492"],"award-info":[{"award-number":["81991492"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["82041039"],"award-info":[{"award-number":["82041039"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2021YFC2302604"],"award-info":[{"award-number":["2021YFC2302604"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Key Research and Development Program of China","award":["2013ZX09102041"],"award-info":[{"award-number":["2013ZX09102041"]}]},{"name":"National Key Research and Development Program of China","award":["81991492"],"award-info":[{"award-number":["81991492"]}]},{"name":"National Key Research and Development Program of China","award":["82041039"],"award-info":[{"award-number":["82041039"]}]},{"name":"National Key Research and Development Program of China","award":["2021YFC2302604"],"award-info":[{"award-number":["2021YFC2302604"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background: Respiratory syncytial virus (RSV) poses a significant global health threat, particularly to children and the elderly. While progress has been made in RSV vaccine development, gaps remain, especially in protecting the elderly population. BARS13, a recombinant non-glycosylated G protein-based RSV vaccine, has shown promise in preclinical and Phase 1 studies. This phase II trial sought to determine whether escalating doses of BARS13 could enhance immune responses while maintaining safety and tolerability in healthy older adults aged 60\u201380 years. Methods: This study employed a rigorous randomized, double-blind, placebo-controlled design involving 125 participants across two Australian centers. Participants were randomized in a 3:1 (vaccine\u2013placebo) ratio for Cohorts 1\u20132 (30 active, 10 placebo each) and a 2:1 ratio for Cohort 3 (30 active, 15 placebo). Cohort 1 (low dose) received 10 \u00b5g rRSV-G + 10 \u00b5g CsA in one arm + a placebo in the other (Days 1 and 29); Cohort 2 (high dose) received 10 \u00b5g rRSV-G + 10 \u00b5g CsA in both arms (20 \u00b5g total per dose, Days 1 and 29); Cohort 3 (multi-dose) received the same dose as that of Cohort 2 but with a third dose on Day 57. The placebo groups received IM injections in both arms at matching timepoints. The primary endpoints included safety and tolerability assessments, while the secondary endpoints evaluated the RSV G protein-specific IgG antibody concentrations using enzyme-linked immunosorbent assays (ELISAs). Statistical analysis was performed on both the safety and immunogenicity populations. Results: BARS13 was well-tolerated across all cohorts, with no serious adverse events (SAEs) related to the vaccine. The most common adverse events were mild local reactions (pain and tenderness) and systemic reactions (headache and fatigue), which resolved within 24\u201348 h. Immunogenicity analysis demonstrated a dose-dependent increase in the RSV G protein-specific IgG geometric mean concentrations (GMCs). Cohort 3, which received multiple high-repeat dose administrations, showed the highest immune response, with the IgG GMC rising from 1195.4 IU\/mL on Day 1 to 1681.5 IU\/mL on Day 113. Response rates were also the highest in Cohort 3, with 86.2% of participants showing an increase in antibody levels by Day 29. Conclusions: BARS13 demonstrated a favorable safety profile and strong immunogenicity in elderly participants, with a clear dose-dependent antibody response. These results support further development of BARS13 as a potential RSV vaccine candidate for the elderly. Further studies are needed to evaluate the long-term efficacy and optimal dosing schedule.<\/jats:p>","DOI":"10.3390\/vaccines13080885","type":"journal-article","created":{"date-parts":[[2025,8,22]],"date-time":"2025-08-22T07:41:45Z","timestamp":1755848505000},"page":"885","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["A Phase II Random, Double-Blind, Placebo-Controlled Study of the Safety and Immunogenicity of a Recombinant G Protein-Based Respiratory Syncytial Virus Vaccine in Healthy Older Adults"],"prefix":"10.3390","volume":"13","author":[{"given":"Lunan","family":"Zhang","sequence":"first","affiliation":[{"name":"Key Laboratory of Medical Molecular Virology (MOE\/NHC\/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China"},{"name":"Advaccine Biopharmaceuticals Suzhou Co., Ltd., Suzhou 215000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gan","family":"Zhao","sequence":"additional","affiliation":[{"name":"Advaccine Biopharmaceuticals Suzhou Co., Ltd., Suzhou 215000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xin","family":"Cheng","sequence":"additional","affiliation":[{"name":"Advaccine Biopharmaceuticals Suzhou Co., Ltd., Suzhou 215000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shuo","family":"Wang","sequence":"additional","affiliation":[{"name":"Advaccine Biopharmaceuticals Suzhou Co., Ltd., Suzhou 215000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiarong","family":"Wang","sequence":"additional","affiliation":[{"name":"Advaccine Biopharmaceuticals Suzhou Co., Ltd., Suzhou 215000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuefen","family":"Huai","sequence":"additional","affiliation":[{"name":"Advaccine Biopharmaceuticals Suzhou Co., Ltd., Suzhou 215000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu","family":"Xia","sequence":"additional","affiliation":[{"name":"Advaccine Biopharmaceuticals Suzhou Co., Ltd., Suzhou 215000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanling","family":"Xiao","sequence":"additional","affiliation":[{"name":"Advaccine Biopharmaceuticals Suzhou Co., Ltd., Suzhou 215000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sulin","family":"Ren","sequence":"additional","affiliation":[{"name":"Advaccine Biopharmaceuticals Suzhou Co., Ltd., Suzhou 215000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shijie","family":"Zhang","sequence":"additional","affiliation":[{"name":"Advaccine Biopharmaceuticals Suzhou Co., Ltd., Suzhou 215000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6416-1733","authenticated-orcid":false,"given":"Qiao","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Medical Molecular Virology (MOE\/NHC\/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9945-1818","authenticated-orcid":false,"given":"Bin","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Medical Molecular Virology (MOE\/NHC\/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China"},{"name":"Advaccine Biopharmaceuticals Suzhou Co., Ltd., Suzhou 215000, China"},{"name":"Children\u2019s Hospital, Fudan University, Shanghai 200032, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1241","DOI":"10.1016\/S0140-6736(24)00138-7","article-title":"Global disease burden of and risk factors for acute lower respiratory infections caused by respiratory syncytial virus in preterm infants and young children in 2019: A systematic review and meta-analysis of aggregated and individual participant data","volume":"403","author":"Wang","year":"2024","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e13031","DOI":"10.1111\/irv.13031","article-title":"Respiratory syncytial virus disease burden in adults aged 60 years and older in high-income countries: A systematic literature review and meta-analysis","volume":"17","author":"Savic","year":"2023","journal-title":"Influenza Other Respir. 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