Olubukola T Idoko, Sergio L Vargas, Agustin Bueso, Doris Rivera, Henderson Edward, Michael Simon, Peyman Banooni, Shaun Berger, Stephane Janicot, Camille Vercasson, Sophie Pallardy, Rapi Nteene, Haritha Adhikarla, Eric Gerchman, Monica Gasparotto, Scott Gallichan, Enrique Rivas, Ursula J Buchholz, Peter L Collins, Sanie Sesay, Sanjay Gurunathan, Iris De Bruijn, Mandeep S Dhingra
{"title":"Live-Attenuated Intranasal RSV Vaccine in Infants and Toddlers.","authors":"Olubukola T Idoko, Sergio L Vargas, Agustin Bueso, Doris Rivera, Henderson Edward, Michael Simon, Peyman Banooni, Shaun Berger, Stephane Janicot, Camille Vercasson, Sophie Pallardy, Rapi Nteene, Haritha Adhikarla, Eric Gerchman, Monica Gasparotto, Scott Gallichan, Enrique Rivas, Ursula J Buchholz, Peter L Collins, Sanie Sesay, Sanjay Gurunathan, Iris De Bruijn, Mandeep S Dhingra","doi":"10.1056/EVIDoa2500026","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>RSV/ΔNS2/Δ1313/I1314L (RSVt) (Sanofi) is a candidate live-attenuated intranasal respiratory syncytial virus (RSV) vaccine for infants and toddlers.</p><p><strong>Methods: </strong>This phase I/II randomized clinical trial, conducted at sites in the United States (N=22), Chile (N=2), and Honduras (N=2), enrolled participants 6-18 months of age in four cohorts. In cohort 4, the primary cohort reported in this article, participants were randomly assigned to receive vaccinations on days 0 and 56 of either low-dose (LD) RSVt, high-dose (HD) RSVt, or placebo. Primary safety end points included: unsolicited systemic adverse events 30 minutes post vaccination, and solicited site and systemic reactions 28 days post vaccination. The primary immunogenicity end points were the geometric mean titers of RSV A serum neutralizing antibody after vaccinations 1 (day 56) and 2 (day 84) among RSV-naive participants at baseline.</p><p><strong>Results: </strong>Among 180 participants (LD, N=61; HD, N=58; placebo, N=61), 115 were RSV-naive at baseline (LD, N=45; HD, N=32; placebo, N=38). No unsolicited systemic adverse events occurred within 30 minutes post vaccination in the LD or HD groups. Solicited site reactions were reported by 83.1%, 74.5%, and 68.9% of participants post vaccination 1, and 75.6%, 77.8%, and 55.6% post vaccination 2, in the LD, HD, and placebo groups, respectively. Solicited systemic reactions were reported by 79.7%, 73.2%, and 77.0% of participants post vaccination 1, and 66.7%, 66.7%, and 48.1% post vaccination 2, in the LD, HD, and placebo groups, respectively. Neutralizing antibody titers among RSV-naive participants were 83.7 (95% confidence interval (CI), 49.5 to 142.0), 79.4 (95% CI, 47.2 to 134.0), and 20.6 (95% CI, 16.4 to 25.9) post vaccination 1, and 142.0 (95% CI, 86.4 to 232.2), 107.0 (95% CI, 70.0 to 163.0), and 26.3 (95% CI, 18.8 to 37.0) post vaccination 2, in the LD, HD, and placebo groups, respectively.</p><p><strong>Conclusions: </strong>The RSVt vaccine demonstrated promising immunogenicity profiles at both LD and HD strengths among infants and toddlers, without identified safety concerns. (Funded by Sanofi; ClinicalTrials.gov number, NCT04491877).</p>","PeriodicalId":74256,"journal":{"name":"NEJM evidence","volume":"4 9","pages":"EVIDoa2500026"},"PeriodicalIF":0.0000,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"NEJM evidence","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1056/EVIDoa2500026","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2025/8/26 0:00:00","PubModel":"Epub","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
Background: RSV/ΔNS2/Δ1313/I1314L (RSVt) (Sanofi) is a candidate live-attenuated intranasal respiratory syncytial virus (RSV) vaccine for infants and toddlers.
Methods: This phase I/II randomized clinical trial, conducted at sites in the United States (N=22), Chile (N=2), and Honduras (N=2), enrolled participants 6-18 months of age in four cohorts. In cohort 4, the primary cohort reported in this article, participants were randomly assigned to receive vaccinations on days 0 and 56 of either low-dose (LD) RSVt, high-dose (HD) RSVt, or placebo. Primary safety end points included: unsolicited systemic adverse events 30 minutes post vaccination, and solicited site and systemic reactions 28 days post vaccination. The primary immunogenicity end points were the geometric mean titers of RSV A serum neutralizing antibody after vaccinations 1 (day 56) and 2 (day 84) among RSV-naive participants at baseline.
Results: Among 180 participants (LD, N=61; HD, N=58; placebo, N=61), 115 were RSV-naive at baseline (LD, N=45; HD, N=32; placebo, N=38). No unsolicited systemic adverse events occurred within 30 minutes post vaccination in the LD or HD groups. Solicited site reactions were reported by 83.1%, 74.5%, and 68.9% of participants post vaccination 1, and 75.6%, 77.8%, and 55.6% post vaccination 2, in the LD, HD, and placebo groups, respectively. Solicited systemic reactions were reported by 79.7%, 73.2%, and 77.0% of participants post vaccination 1, and 66.7%, 66.7%, and 48.1% post vaccination 2, in the LD, HD, and placebo groups, respectively. Neutralizing antibody titers among RSV-naive participants were 83.7 (95% confidence interval (CI), 49.5 to 142.0), 79.4 (95% CI, 47.2 to 134.0), and 20.6 (95% CI, 16.4 to 25.9) post vaccination 1, and 142.0 (95% CI, 86.4 to 232.2), 107.0 (95% CI, 70.0 to 163.0), and 26.3 (95% CI, 18.8 to 37.0) post vaccination 2, in the LD, HD, and placebo groups, respectively.
Conclusions: The RSVt vaccine demonstrated promising immunogenicity profiles at both LD and HD strengths among infants and toddlers, without identified safety concerns. (Funded by Sanofi; ClinicalTrials.gov number, NCT04491877).