{
  "abstract": "Background\n\nHemophilia B is a rare, X-linked disorder leading to deficient or dysfunctional clotting factor IX and bleeding complications.Objectives\n\nThe objective of this systematic review and meta-analysis was to summarize bleeding events in people with hemophilia B of any severity without inhibitors receiving prophylactic factor IX replacement therapies to better understand disease burden and unmet needs.Methods\n\nA systematic search was conducted to identify clinical trials and observational studies reporting annualized bleeding rate (ABR), annualized joint bleeding rate, spontaneous bleeding events, traumatic bleeding events, and percentage of patients with zero-bleeding events. Bleeding outcomes were specified as total, treated, or unspecified and analyzed using the random-effects model. Subgroup meta-analyses assessed differences by age, treatment type, follow-up duration, and publication date, when feasible.Results\n\nThe search yielded 5684 citations; 24 clinical trials and 53 observational studies were included in the meta-analysis. Treated ABR was 2.23 (95% CI, 1.52-3.27) in 13 trials; treated or unspecified ABR was 2.25 (95% CI, 1.67-3.03) in 22 trials. In 48 observational studies, treated or unspecified ABR was 2.08 (95% CI, 1.62-2.66). ABR was generally lower for patients <12 years of age (vs ≥12 years of age) and patients treated with extended half-life (vs standard half-life).Conclusion\n\nResults from this meta-analysis reflect advances in hemophilia B treatment, but also highlight unmet needs, with many patients experiencing ≥2bleeding events per year. Inconsistent ABR definitions and variability in follow-up times may introduce heterogeneity in the combined estimates.",
  "abstract_shown": true,
  "affiliations": [
    "Evidence Synthesis, IQVIA, Falls Church, Virginia, USA.",
    "Evidence Synthesis, IQVIA, San Mateo, California, USA.",
    "Pfizer, New York City, New York, USA.",
    "Pfizer, Montreal, Quebec, Canada.",
    "Pfizer, Collegeville, Pennsylvania, USA.",
    "Departments of Pediatrics and Pathology, University of Michigan, Ann Arbor, Michigan, USA.",
    "Hemostasis and Thrombosis Center, Cancer and Blood Disease Institute, Children's Hospital Los Angeles, Los Angeles, California, USA."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 10,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Kristina Lindsley"
    },
    {
      "affs": [
        1
      ],
      "name": "Arianna Nevo"
    },
    {
      "affs": [
        2
      ],
      "name": "Carmine Colavecchia"
    },
    {
      "affs": [
        3
      ],
      "name": "Lisa J Wilcox"
    },
    {
      "affs": [
        2
      ],
      "name": "Priya Patel"
    },
    {
      "affs": [
        4
      ],
      "name": "Carlos Estevez"
    },
    {
      "affs": [
        3
      ],
      "name": "Cynthia Khanji"
    },
    {
      "affs": [
        1
      ],
      "name": "Jennifer Uyei"
    },
    {
      "affs": [
        5
      ],
      "name": "Steven W Pipe"
    },
    {
      "affs": [
        6
      ],
      "name": "Guy Young"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/950p7q35zf7ac.bib",
  "cited_by": 0,
  "doi": "10.1016/j.rpth.2026.106954",
  "fulltext_url": "https://europepmc.org/articles/PMC13685439",
  "id": "950p7q35zf7ac",
  "issns": [
    "2475-0379"
  ],
  "landing_url": "https://europepmc.org/article/MED/42910129",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2720|Hemophilia Treatment and Research"
    ]
  ],
  "openalex": "W7211987813",
  "pdf_url": "https://europepmc.org/articles/PMC13685439?pdf=render",
  "pmcid": "PMC13685439",
  "pmid": "42910129",
  "published": "2026-09-09",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/950p7q35zf7ac.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:20:14Z",
      "native_id": "MED:42910129",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42910129"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2720|Hemophilia Treatment and Research",
      "subfield": "general"
    }
  ],
  "title": "Bleeding events in people with hemophilia B on prophylactic factor IX treatment: a systematic review and meta-analysis.",
  "title_text": "Bleeding events in people with hemophilia B on prophylactic factor IX treatment: a systematic review and meta-analysis.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:20:14Z",
  "url": "https://research.draconitic.com/paper/950p7q35zf7ac",
  "venue": "Research and practice in thrombosis and haemostasis",
  "versions": []
}