Work

Bleeding events in people with hemophilia B on prophylactic factor IX treatment: a systematic review and meta-analysis

Year: 2026

Type: review

Study designs: Systematic Review, Meta-Analysis

Abstract: Background: Hemophilia B is a rare, X-linked disorder leading to deficient or dysfunctional clotting factor IX and bleeding complications. Objectives: The 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: A 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: The 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: Results 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.

Source: Research and Practice in Thrombosis and Haemostasis

DOI: 10.1016/j.rpth.2026.106954