{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T00:59:51Z","timestamp":1760057991801,"version":"build-2065373602"},"reference-count":48,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,3,5]],"date-time":"2025-03-05T00:00:00Z","timestamp":1741132800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Pfizer, Inc."}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background: Assessing the real-world safety of preventive products against respiratory syncytial virus (RSV) in pregnant women holds significant public health implications, especially as vaccination programs become more widespread. This generic protocol describes a post-authorisation safety study (PASS) to evaluate the safety of RSV vaccination in pregnant women using a target trial emulation framework. Methods: This generic protocol, adapted from an ongoing PASS, is designed using the target trial emulation framework to evaluate the safety of an RSV vaccine in pregnant women. Emulating target trial conditions have the ability to minimise confounding and bias. In this pragmatic real-world observational study, RSV-vaccinated pregnant women are matched (1:N) with unexposed women based on gestational age, calendar time, maternal age, immunocompromised status, and high-risk pregnancy. Key adverse outcomes include preterm birth, stillbirth, hypertensive disorders of pregnancy, Guillain-Barr\u00e9 Syndrome (GBS), low birth weight (LBW), and small for gestational age (SGA). Future studies may add additional outcomes per vaccine risk profile and Global Alignment of Immunization safety Assessment (GAIA) recommendations. Distinguishing outcomes measured during pregnancy from those assessed at or after birth is crucial for analysis and interpretation. Conclusions: This protocol offers a structured approach to evaluating the safety of RSV vaccines in pregnant women. It aims to guide researchers in designing studies and should be adapted to specific settings and data availability.<\/jats:p>","DOI":"10.3390\/vaccines13030272","type":"journal-article","created":{"date-parts":[[2025,3,5]],"date-time":"2025-03-05T03:18:22Z","timestamp":1741144702000},"page":"272","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Post-Authorisation Safety Study of a Respiratory Syncytial Virus Vaccine in Pregnant Women and Their Offspring in a Real-World Setting: Generic Protocol for a Target Trial Emulation"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6295-3411","authenticated-orcid":false,"given":"Odette","family":"de Bruin","sequence":"first","affiliation":[{"name":"Department of Data Science & Biostatistics, Julius Global Health, University Medical Center Utrecht (UMCU), 3584CG Utrecht, The Netherlands"},{"name":"Department of Obstetrics, Division Woman and Baby, Wilhelmina Children\u2019s Hospital, University Medical Center Utrecht (UMCU), 3584CG Utrecht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Linda","family":"Nab","sequence":"additional","affiliation":[{"name":"Department of Data Science & Biostatistics, Julius Global Health, University Medical Center Utrecht (UMCU), 3584CG Utrecht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jungyeon","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Data Science & Biostatistics, Julius Global Health, University Medical Center Utrecht (UMCU), 3584CG Utrecht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Oisin","family":"Ryan","sequence":"additional","affiliation":[{"name":"Department of Data Science & Biostatistics, Julius Global Health, University Medical Center Utrecht (UMCU), 3584CG Utrecht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4195-7872","authenticated-orcid":false,"given":"Hae-Won","family":"Uh","sequence":"additional","affiliation":[{"name":"Department of Data Science & Biostatistics, Julius Global Health, University Medical Center Utrecht (UMCU), 3584CG Utrecht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6261-9445","authenticated-orcid":false,"given":"Fariba","family":"Ahmadizar","sequence":"additional","affiliation":[{"name":"Department of Data Science & Biostatistics, Julius Global Health, University Medical Center Utrecht (UMCU), 3584CG Utrecht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shahar","family":"Shmuel","sequence":"additional","affiliation":[{"name":"Safety Surveillance Research Worldwide Medical and Safety, Pfizer, Inc., New York, NY 10001-2192, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Heather","family":"Rubino","sequence":"additional","affiliation":[{"name":"Safety Surveillance Research Worldwide Medical and Safety, Pfizer, Inc., New York, NY 10001-2192, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kitty","family":"Bloemenkamp","sequence":"additional","affiliation":[{"name":"Department of Obstetrics, Division Woman and Baby, Wilhelmina Children\u2019s Hospital, University Medical Center Utrecht (UMCU), 3584CG Utrecht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cynthia","family":"de Luise","sequence":"additional","affiliation":[{"name":"Safety Surveillance Research Worldwide Medical and Safety, Pfizer, Inc., New York, NY 10001-2192, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Miriam","family":"Sturkenboom","sequence":"additional","affiliation":[{"name":"Department of Data Science & Biostatistics, Julius Global Health, University Medical Center Utrecht (UMCU), 3584CG Utrecht, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2047","DOI":"10.1016\/S0140-6736(22)00478-0","article-title":"Global, regional, and national disease burden estimates of acute lower respiratory infections due to respiratory syncytial virus in children younger than 5 years in 2019: A systematic analysis","volume":"399","author":"Li","year":"2022","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e2","DOI":"10.1016\/S1473-3099(22)00291-2","article-title":"Respiratory syncytial virus prevention within reach: The vaccine and monoclonal antibody landscape","volume":"23","author":"Mazur","year":"2023","journal-title":"Lancet Infect. 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