A real-world evidence analysis of the impact of switching from factor VIII to emicizumab prophylaxis in patients with hemophilia A without inhibitors.

BACKGROUND: This study retrospectively compared annualized billed bleed rates (ABRb) in people with hemophilia A (PwHA) without inhibitors who switched from factor VIII (FVIII) prophylaxis to emicizumab. RESEARCH DESIGN AND METHODS: A real-world comparison study was performed on the effect of switching from FVIII to emicizumab prophylaxis in male, non-inhibitor patients on ABRb using an all-payer claims database (APCD) dataset from 1 January 2014, to 31 March 2021. The identification period was from 1 November 2017, to 30 September 2020. RESULTS: One hundred and thirty-one patients were included with a total of 82 and 45 bleeds in the pre- and post-switch periods, respectively. The average follow-up period pre-switch was 978.37 days (SD 555.03), whereas the average follow-up period post-switch was 522.26 days (SD 191.36). No significant differences in mean ABRb were observed pre-/post-switch (0.25 and 0.20, respectively; P = 0.4456). CONCLUSIONS: The results of this study demonstrate no significant reduction in ABRb, suggesting that switching from FVIII to emicizumab may not deliver incremental benefits to PwHA receiving prophylactic care.