Abstract Number: PB1161
Meeting: ISTH 2020 Congress
Theme: Hemophilia and Rare Bleeding Disorders » Novel Biotherapeutics in Hemophilia
Background: Emicizumab, a humanized bispecific antibody factor VIII mimetic, has improved convenience for hemophilia A prophylaxis with decreased annualized bleeding rates (ABR). However, the functional impact of emicizumab on joint outcomes has been less explored.
Aims: To explore joint physical exam outcomes and physical activity in a cohort of persons with hemophilia A (PwHA) on emicizumab.
Methods: Data regarding age, inhibitor status, prior treatment, physical activity, ABR, and Hemophilia Joint Health Scores (HJHS) on PwHA on emicizumab for >6 months were extracted from a consented, single-center cohort study (HemoPICS). Joint ABR (J-ABR) and HJHS progression (annualized change in 6-joint average scores) for each participant were compared before and after starting emicizumab using a related-samples Wilcoxon Signed Rank test.
Results: Data from 58 PwHA, with baseline FVIII levels < 1% to 6%, were analyzed. Median age of emicizumab start was 12.8 (range 0.6-79.8) years. Median time on emicizumab was 10.9 (range 6.2-44.2) months. Twelve school-aged children participated in 1 or more sports, including soccer, baseball, tennis, cross-country track, swimming, and alpine skiing, without regular FVIII prophylaxis. At emicizumab start, 9 participants had active inhibitors, and 49 did not, including 39 (80%) on FVIII prophylaxis. J-ABR decreased in all patients (p=0.03), including in patients without an inhibitor (80% previously on FVIII prophylaxis) (Figure 1) HJHS progression slowed in the overall group (p=0.03), but this was not significant in subgroup analyses (Figure 2). Surprisingly, neither pre-emicizumab J-ABR nor rate of HJHS progression predicted subsequent outcomes.
Conclusions: Following adoption of emicizumab by PwHA, HJHS and bleeding rates were stable or improved, including in those previously on full prophylaxis with FVIII, and including a few school-aged children who participated in sports. Emicizumab may improve bleeding and progression of arthropathy in PwHA with active inhibitors, those using episodic therapy and also in those on FVIII prophylaxis.
[Figure 1: J-ABR before and after emicizumab (Emi)]
[Figure 2: Annualized change in average HJHS before and after emicizumab (Emi).]
To cite this abstract in AMA style:
Warren BB, Thornhill D, Smith J, Shearer R, Moyer G, Fox L, O'Connell M, Horton R, Funk S, Chan A, Gibson E, Ng C, Buckner TW, Branchford B, Manco-Johnson MJ, Wang M. Emicizumab, beyond Annualized Bleeding Rates: Real World Joint Health and Physical Activity Data [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/emicizumab-beyond-annualized-bleeding-rates-real-world-joint-health-and-physical-activity-data/. Accessed March 21, 2024.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/emicizumab-beyond-annualized-bleeding-rates-real-world-joint-health-and-physical-activity-data/