Abstract Number: PB1248
Meeting: ISTH 2020 Congress
Background: The American Thrombosis and Hemostasis Network’s (ATHN) ATHN 8: PUPs Matter Study is the first U.S. cohort study of previously untreated patients (PUPs) with congenital hemophilia. Children with baseline factor VIII or IX levels ≤5% born after January 1, 2010 that are followed at ATHN-affiliated hemophilia treatment centers (HTCs) are enrolled in this multi-center study. The primary objective is to determine the percentage of PUPs with confirmed inhibitors within the first 50 exposure days (ED).
Aims: To provide an interim analysis of the ATHN 8: PUPs Matter Study 2010-2019 birth cohorts.
Methods: The study was approved by each HTC’s institutional review board and informed consent was obtained prior to implementing study procedures. Demographic, laboratory, and clinical data are being collected. All participants are being followed until 50 exposure days or until inhibitor development. Descriptive statistics are used to analyze participant characteristics for an interim analysis through August 31, 2019.
Results: Nineteen HTCs have enrolled 79 male participants thus far. The majority have severe hemophilia A. [Table 1] Family history for hemophilia at diagnosis was present in 52%. Age at first product exposure is known for 56 (71%). Forty-nine (88%) had their first treatment within the first year of life, with 20 (25%) receiving treatment within the first month. Most participants (59%) received recombinant factor at first exposure. [Table 2] One or more inhibitor titer test is documented for 59 (75%), and, to date, 14 (18%) have met the primary endpoint for inhibitor development.
Conclusions: The interim analysis provides clinical information for PUPs born between 2010-2019. Planned enrollment is 250 participants. This study will provide important information regarding inhibitor development and the changing treatment landscape.
| N=79 | Birth Cohort 2010-2019 |
| Age, years (median, range) | 4.2 (0.3-9.1) |
| Birth year, N (%) 2010-2012, 2013-2015, 2016-2018, 2019- | 15 (19), 29 (37), 33 (42), 2 (3) |
| Race, N (%) White, Black/African American, Asian, Mixed Race, Unknown | 66 (84), 6 (8), 3 (4), 3 (4) 1 (1) |
| Ethnicity, N (%) Non-Hispanic | 63 (80) |
| Primary Diagnosis, N (%) Hemophilia A, moderate; Hemophilia A, severe; Hemophilia B, moderate; Hemophilia B, severe | 8 (10), 60 (76), 2 (3), 9 (11) |
| Prenatal Diagnosis, N (%) Yes | 3 (4) |
| Reason for diagnostic testing, N (%) Bleeding symptoms, Mother known carrier, Other family history, Abnormal pre-operative screening, Other Unknown | 43 (54), 16 (20), 10 (13), 1 (1), 3 (4), 6 (8) |
| Gene variant identified, N (%) Hemophilia A (N=68); Hemophilia B (N=11) | 43 (63), 7 (64) |
[Table 1. Demographic and Diagnostic Characteristics]
| N = 79 | |
| Primary treatment type, N (%) Prophylaxis (continuous), Prophylaxis (event-based), Episodic, None, Unknown | 39 (49), 2 (3), 23 (29), 1 (1), 14 (18) |
| Primary treatment product type, N (%) Recombinant factor, Plasma-derived factor, Bypassing therapy, Non-factor therapy, None Unknown | 52 (66), 9 (11), 2 (3), 1 (1), 1 (1), 14 (18) |
| Home infusion, N (%) | 56 (71) |
| Age at first home infusion (N=56), <1 y, 1-1.99 y, 2+y | 27 (48), 21 (38), 8 (14) |
[Table 2. Treatment Characteristics]
To cite this abstract in AMA style:
Carpenter S, He C, Malec L, Payne A, van den Berg M, Watson C, Thornburg C. U.S. Cohort Study of Previously Untreated Patients with Congenital Hemophilia (ATHN 8: PUPS Matter Study) Interim Analysis of the 2010-2019 Birth Cohort [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/u-s-cohort-study-of-previously-untreated-patients-with-congenital-hemophilia-athn-8-pups-matter-study-interim-analysis-of-the-2010-2019-birth-cohort/. Accessed November 29, 2023.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/u-s-cohort-study-of-previously-untreated-patients-with-congenital-hemophilia-athn-8-pups-matter-study-interim-analysis-of-the-2010-2019-birth-cohort/