{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T11:35:22Z","timestamp":1788348922572,"version":"build-2803163510"},"reference-count":32,"publisher":"Georg Thieme Verlag KG","issue":"05","license":[{"start":{"date-parts":[[2025,7,28]],"date-time":"2025-07-28T00:00:00Z","timestamp":1753660800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100004331","name":"Johnson & Johnson","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100004331","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Am J Perinatol"],"published-print":{"date-parts":[[2026,4]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Nipocalimab, a neonatal Fc receptor blocker, inhibits transplacental transfer of maternal immunoglobulin G (IgG) and lowers circulating maternal IgG levels. In a phase 2 study, nipocalimab demonstrated evidence of safety and efficacy in delaying or preventing fetal anemia in early-onset severe hemolytic disease of the fetus and newborn, suggesting a potential benefit in other IgG alloantibody-mediated perinatal diseases, including fetal and neonatal alloimmune thrombocytopenia (FNAIT). The phase 3 FREESIA-1 study aims to evaluate the safety and efficacy of nipocalimab in at-risk FNAIT pregnancies.<\/jats:p>\n                  <jats:p>This multicenter, placebo-controlled, double-blind, phase 3 study will enroll human platelet antigen (HPA)-1a-alloimmunized pregnant individuals with an HPA-1a-positive fetus and prior FNAIT-affected pregnancy without intracranial hemorrhage or severe bleeding in the fetus\/newborn. Participants will be randomized 2:1 to weekly intravenous nipocalimab or placebo at 13 to 18 weeks of gestation until delivery. Maternal participants will receive ultrasound monitoring approximately every 2 weeks during treatment. Neonates will receive a cranial ultrasound scan, platelet count assessment, and, if needed, platelet transfusion. Maternal participants will be followed for 24 weeks and neonates\/infants for 104 weeks.<\/jats:p>\n                  <jats:p>The primary endpoint is an adverse outcome of fetal death or adjudicated severe bleeding in utero up to 1 week postbirth, or neonatal platelet count at birth\u2009&lt;\u200930\u2009\u00d7\u2009109\/L. Key secondary endpoints include adjudicated bleeding in utero up to the first week postbirth in fetuses\/neonates and platelet count at birth in neonates. Additional secondary endpoints in fetuses\/neonates include death; platelet count at birth &lt;10, &lt;30, &lt;50, and &lt;150\u2009\u00d7\u2009109\/L; nadir platelet count over the first week postbirth; platelet transfusion; adjudicated severe bleeding up to the first week postbirth; and postnatal intravenous immunoglobulin for thrombocytopenia. Other assessments include safety, patient\/caregiver-reported outcomes, pharmacokinetics, pharmacodynamics, and immunogenicity of nipocalimab.<\/jats:p>\n                  <jats:p>FREESIA-1 is the first placebo-controlled, randomized, multicenter trial designed to evaluate the safety and efficacy of nipocalimab in at-risk FNAIT pregnancies. (ClinicalTrials.gov Identifier: NCT06449651. Accessed at: https:\/\/clinicaltrials.gov\/study\/NCT06449651. Date of registration: June 10, 2024.)<\/jats:p>","DOI":"10.1055\/a-2666-5642","type":"journal-article","created":{"date-parts":[[2025,7,28]],"date-time":"2025-07-28T22:43:00Z","timestamp":1753742580000},"page":"648-656","source":"Crossref","is-referenced-by-count":12,"title":["Design of a Phase 3, Multicenter, Randomized, Placebo-Controlled, Double-Blind Study of Nipocalimab in Pregnancies at Risk for Fetal and Neonatal Alloimmune Thrombocytopenia"],"prefix":"10.1055","volume":"43","clinical-trial-number":[{"clinical-trial-number":"nct06449651","registry":"10.18810\/clinical-trials-gov"}],"author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3250-0750","authenticated-orcid":false,"given":"Heidi","family":"Tiller","sequence":"additional","affiliation":[{"name":"Department of Clinical Medicine, UiT The Arctic University of Norway, Troms\u00f8, Norway"},{"name":"Department of Obstetrics and Gynecology, University Hospital of North Norway, Troms\u00f8, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eleonor","family":"Tiblad","sequence":"additional","affiliation":[{"name":"Clinical Epidemiology Division, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pamela","family":"Baker","sequence":"additional","affiliation":[{"name":"Johnson & Johnson, Spring House, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hillary","family":"Van Valkenburgh","sequence":"additional","affiliation":[{"name":"Johnson & Johnson, Spring House, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dirk","family":"Heerwegh","sequence":"additional","affiliation":[{"name":"Johnson & Johnson, Beerse, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Babajide","family":"Keshinro","sequence":"additional","affiliation":[{"name":"Johnson & Johnson, Biologics BV, Leiden, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2025,8,20]]},"reference":[{"issue":"04","key":"ref1","doi-asserted-by":"crossref","first-page":"715","DOI":"10.1542\/peds.2013-3320","article-title":"Incidence and consequences of neonatal alloimmune thrombocytopenia: a systematic review","volume":"133","author":"M M Kamphuis","year":"2014","journal-title":"Pediatrics"},{"issue":"01","key":"ref2","doi-asserted-by":"crossref","first-page":"102704","DOI":"10.1016\/j.transci.2019.102704","article-title":"Epidemiology and management of fetal and neonatal alloimmune thrombocytopenia","volume":"59","author":"T W de Vos","year":"2020","journal-title":"Transfus Apher Sci"},{"issue":"11","key":"ref3","doi-asserted-by":"crossref","first-page":"1538","DOI":"10.1182\/blood-2016-10-739656","article-title":"Antenatal management in fetal and neonatal alloimmune thrombocytopenia: a systematic review","volume":"129","author":"D 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