AUTHORS
Fernando Corrales-Medina, MD, Nana Ama Afari-Dwamena, MPH2, Brian Branchford, MD3, Shannon L. Carpenter, MD MS4, Daisy Cortes, MD5, Beng Fuh, MD, PhD6, Jianzhong Hu, PhD7, Tammuella Chrisentery-Singleton, MD8
AFFILIATIONS
1 University of Miami-Hemophilia and Thrombosis Treatment Center, Miami, Florida, United States, University of Miami-Miller School of Medicine, Miami, Florida, United States
2 American Thrombosis & Hemostasis, Hickory, North Carolina, United States
3 Versiti Blood Research Institute, Blood Center of Wisconsin, Milwaukee, Wisconsin, United States
4 Kansas City Regional Hemophilia Center, The Children’s Mercy Hospital, Kansas City, Missouri, United States
5 Hemostasis & Thrombosis Center of Nevada, Las Vegas, Nevada, United States
6 East Carolina University Health, Greenville, North Carolina, United States
7 American Thrombosis & Hemostasis, Hickory, North Carolina, United States
8 American Thrombosis & Hemostasis, Hickory, North Carolina, United States, Ochsner Clinic Foundation, New Orleans, Louisiana, United States
ABSTRACT
Background
Historically, females with hemophilia have been underdiagnosed and underrepresented in clinical research despite increasing recognition that they may also experience clinically significant bleeding symptoms regardless of baseline factor activity level. However, real-world data describing their collective clinical characteristics, treatment patterns, and healthcare resource utilization remain limited.
Aim
To describe the baseline clinical characteristics of females with hemophilia enrolled in the ATHN Transcends study.
Methods
ATHN Transcends is an ongoing, multicenter, prospective natural history study initiated in September 2020 across more than 70 ATHN-affiliated hemophilia treatment centers (HTCs) in the United States. Females with hemophilia A (HA) or hemophilia B (HB), including carriers of pathogenic F8 or F9 variants regardless of factor activity, are eligible for enrollment. Female participants enrolled through March 2, 2026, were included in this analysis. Demographic characteristics, disease severity, baseline factor activity, bleeding history, treatment regimen, procedures, healthcare utilization, and patient-reported outcomes were analyzed with descriptive statistics.
Results
A total of 48 females with hemophilia were enrolled, including 30 (62.5%) with HA and 18 (37.5%) with HB. The mean age at enrollment was 23.9 ± 19.3 years (median, 16 years; range, 2–78). Among participants with HA, 2 (6.7%) had severe disease, 1 (3.3%) had moderate disease, 19 (63.3%) had mild disease, and 8 (26.7%) had baseline FVIII activity >40 IU/dL, with a mean FVIII activity of 33.1 ± 16.0 IU/dL. Among participants with HB, 1 (5.6%) had moderate disease, 16 (88.9%) had mild disease, and 1 (5.6%) had baseline FIX activity >40 IU/dL, with a mean FIX activity of 28.8 ± 12.1 IU/dL.
Among the 28 participants with available bleeding history, the mean age at first bleeding event was 10 ± 10.98 years (median, 6.5 years; range, 0-49). No participant had a documented history of inhibitors, and only one participant with HA had a documented target joint (ankle).
Baseline hemostatic treatment data were available for 45 participants. Episodic therapy was the predominant treatment strategy, reported in 36 (80.0%), whereas prophylaxis was reported in 5 (11.1%) participants (4 HA and 1 HB). The 2 participants with severe HA were receiving emicizumab prophylaxis. The remaining 3 participants reported clotting factor concentrate (CFC)-based prophylaxis with standard half-life (SHL) FVIII, ultra-extended half-life (UHL) FVIII, and extended half-life (EHL) FIX concentrates, respectively. Additionally, 6 participants (13.3%) received routine tranexamic acid for management of heavy menstrual bleeding.
For acute bleeding management, antifibrinolytics were the most commonly prescribed hemostatic agents (26, 57.8%), followed by SHL FVIII (15, 33.3%), SHL FIX (13, 28.9%), EHL FIX (5, 11.1%), desmopressin (5, 11.1%), and UHL FVIII (1, 2.2%). One HA participant (2.2%) had a plasma-derived FVIII concentrate prescribed. Most participants prescribed antifibrinolytics also had a CFC available for breakthrough bleeding management.
Despite generally favorable self-perceived health (mean EQ-5D visual analog scale score, 76.7/100), participants demonstrated substantial historical healthcare resource utilization, reporting 186 procedures prior to enrollment, including 12 (6.5%) associated with perioperative bleeding complications. Most participants (47, 97.9%) reported at least 1 comprehensive HTC visit prior to enrollment.
Conclusions
Females with hemophilia currently enrolled in ATHN Transcends are predominantly characterized by mild disease or residual factor activity >40 IU/dL. Substantial healthcare resource utilization and reliance on specialized HTC care remain common within this population. These baseline findings highlight that females with hemophilia represent a clinically heterogeneous population and support continued efforts toward earlier recognition and individualized multidisciplinary management. These findings should be interpreted in the context of a cohort enrolled through federally funded HTCs and may not be representative of all females with hemophilia.
DISCLOSURES
Fernando Corrales-Medina, MD: Octapharma - Research Funding; Sanofi - Consultancy (Includes expert testimony); Bayer - Consultancy (Includes expert testimony); Takeda - Consultancy (Includes expert testimony); Octapharma - Consultancy (Includes expert testimony); Genentech - Consultancy (Includes expert testimony); Novo Nordisk - Consultancy (Includes expert testimony)