{"doi":"10.1111/irv.12555","title":"The safety and efficacy of quadrivalent live attenuated influenza vaccine in Japanese children aged 2‐18 years: Results of two phase 3 studies","abstract":"BackgroundQuadrivalent live attenuated influenza vaccine (Q/LAIV) has not been assessed in Japanese children.ObjectivesEvaluate safety and efficacy of Q/LAIV in Japanese children.Patients/methodsTwo phase 3 studies were conducted in the 2014‐2015 influenza season. Study 1 was an open‐label, uncontrolled single arm, multicenter study of Q/LAIV safety in subjects aged 2‐6 years. Study 2 was a randomized, double‐blind, placebo‐controlled multicenter study of Q/LAIV safety and efficacy; subjects aged 7‐18 years were randomized 2:1 to receive Q/LAIV or placebo. Primary efficacy endpoint was laboratory‐confirmed symptomatic influenza infection caused by vaccine‐matched strains; secondary endpoint evaluated efficacy against all strains regardless of match. Both studies reported solicited symptoms, adverse events (AEs), and serious AEs.ResultsIn Study 1, 100 subjects received Q/LAIV. In Study 2, 1301 subjects received Q/LAIV (n = 868) or placebo (n = 433). Treatment‐emergent AEs occurred in 42% of subjects in Study 1, and in 24.3% of subjects in the Q/LAIV arm and in 25.9% of subjects in the placebo arm in Study 2. In Study 2, a single infection by a vaccine‐matched strain was reported in the placebo arm, resulting in a vaccine efficacy estimate of 100% (95% CI: −1875.3, 100.0); efficacy for all strains regardless of match to the vaccine was 27.5% (95% CI: 7.4, 43.0).ConclusionsQuadrivalent live attenuated influenza vaccine did not meet its primary efficacy endpoint as only a single infection by a vaccine‐matched strain was detected; however, efficacy for the secondary endpoint, all strains regardless of match, was achieved. Q/LAIV was generally well tolerated in the Japanese pediatric population.","journal":"Influenza and Other Respiratory Viruses","year":2018,"id":639177,"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":969419,"name":"Jing Yu","orcid":"0000-0003-2485-2286","position":1,"is_corresponding":false},{"id":1660530,"name":"Sachiko Kameo","orcid":null,"position":2,"is_corresponding":false},{"id":1624735,"name":"Michio Tanaka","orcid":null,"position":3,"is_corresponding":false},{"id":1660531,"name":"Ki Rito","orcid":null,"position":4,"is_corresponding":false},{"id":1660532,"name":"Yohji Itoh","orcid":null,"position":5,"is_corresponding":false},{"id":804745,"name":"Filip Dubovsky","orcid":null,"position":6,"is_corresponding":false},{"id":1357014,"name":"Raburn M. Mallory","orcid":"0000-0002-2563-9981","position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"The safety and efficacy of quadrivalent live attenuated influenza vaccine in Japanese children aged 2‐18 years: Results of two phase 3 studies","abstract":"BackgroundQuadrivalent live attenuated influenza vaccine (Q/LAIV) has not been assessed in Japanese children.ObjectivesEvaluate safety and efficacy of Q/LAIV in Japanese children.Patients/methodsTwo phase 3 studies were conducted in the 2014‐2015 influenza season. Study 1 was an open‐label, uncontrolled single arm, multicenter study of Q/LAIV safety in subjects aged 2‐6 years. Study 2 was a randomized, double‐blind, placebo‐controlled multicenter study of Q/LAIV safety and efficacy; subjects aged 7‐18 years were randomized 2:1 to receive Q/LAIV or placebo. Primary efficacy endpoint was laboratory‐confirmed symptomatic influenza infection caused by vaccine‐matched strains; secondary endpoint evaluated efficacy against all strains regardless of match. Both studies reported solicited symptoms, adverse events (AEs), and serious AEs.ResultsIn Study 1, 100 subjects received Q/LAIV. In Study 2, 1301 subjects received Q/LAIV (n = 868) or placebo (n = 433). Treatment‐emergent AEs occurred in 42% of subjects in Study 1, and in 24.3% of subjects in the Q/LAIV arm and in 25.9% of subjects in the placebo arm in Study 2. In Study 2, a single infection by a vaccine‐matched strain was reported in the placebo arm, resulting in a vaccine efficacy estimate of 100% (95% CI: −1875.3, 100.0); efficacy for all strains regardless of match to the vaccine was 27.5% (95% CI: 7.4, 43.0).ConclusionsQuadrivalent live attenuated influenza vaccine did not meet its primary efficacy endpoint as only a single infection by a vaccine‐matched strain was detected; however, efficacy for the secondary endpoint, all strains regardless of match, was achieved. Q/LAIV was generally well tolerated in the Japanese pediatric population.","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":"29573143","pmcid":"PMC6005581","openalex_id":"https://openalex.org/W2794060446","authors":[],"funders":[{"funder_name":"AstraZeneca","grant_id":"","title":null}],"total_grants":1,"fwci":0.9014,"citation_percentile":0.73349851,"influential_citations":0,"citation_trend":[{"year":2018,"count":1},{"year":2019,"count":1},{"year":2020,"count":3},{"year":2021,"count":1},{"year":2022,"count":2},{"year":2023,"count":2},{"year":2024,"count":3},{"year":2025,"count":4},{"year":2026,"count":1}],"oa_status":"gold","license":"cc-by","oa_locations":[{"url":"https://doi.org/10.1111/irv.12555","host_type":"journal"},{"url":"https://doi.org/10.1111/irv.12555","host_type":"publisher"},{"url":"https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Firv.12555","host_type":"publisher"},{"url":"https://onlinelibrary.wiley.com/doi/pdf/10.1111/irv.12555","host_type":"publisher"},{"url":"https://pubmed.ncbi.nlm.nih.gov/29573143","host_type":"repository"},{"url":"http://europepmc.org/pmc/articles/PMC6005581","host_type":"repository"},{"url":"https://www.ncbi.nlm.nih.gov/pmc/articles/6005581","host_type":"repository"},{"url":"https://europepmc.org/articles/PMC6005581","host_type":"Europe_PMC"},{"url":"https://europepmc.org/articles/PMC6005581?pdf=render","host_type":"Europe_PMC"}],"fields_of_study":["Influenza Virus Research Studies","Respiratory viral infections research","SARS-CoV-2 and COVID-19 Research"],"mesh_terms":["Adolescent","Child","Child, Preschool","Double-Blind Method","Female","Humans","Influenza, Human","Influenza Vaccines","Japan","Male"],"keywords":["Live attenuated influenza vaccine","Medicine","Clinical endpoint","Placebo","Adverse effect","Vaccine efficacy","Internal medicine","Influenza vaccine","Randomized controlled trial","Vaccination","Immunology","Pathology","Japan","Pediatric","Seasonal Influenza","Laiv"],"sdg_mappings":[{"sdg_number":0,"sdg_label":"Good health and well-being"}],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[{"name":"nct"}],"source":"live","citation_network_status":"fetched"},"created_at":"2026-08-06T22:48:24.395863Z","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":[]}