Trends in prescribing practices for management of haemophilia: 1999-2021.

INTRODUCTION: People with haemophilia rely on specialists for their care, yet the specific dosing regimens of treatments prescribed by these specialists have not been widely studied.

AIM: The objective of this study is to describe trends in clinician prescribing practices for the management of haemophilia in the United States (US).

METHODS: We administered surveys to members of the Hemostasis and Thrombosis Research Society via paper surveys at its in-person annual symposia in 1999 and 2015, and an online survey in 2021. The surveys collected information on haemophilia treatments including factor dosing, inhibitor therapy and gene therapy.

RESULTS: Clinicians treating haemophilia for more than 50% of their practice time have increased from 37.5% of respondents in 1999 to 46.3% in 2021. Clinicians prescribing factor concentrates at >40 units/kg for routine bleeding events increased from 0% in 1999 to 29.3% in 2021 in haemophilia A (HA) and from 22.5% to 87.8% in haemophilia B (HB). In 2021, the clinicians reported prescribing emicizumab to treat HA patients (>89.5% paediatric, >85.7% adult) with or without inhibitors at least some of the time. Approximately 78.0% of respondents reported that they expected to recommend gene therapy at least some of time.

CONCLUSION: These data indicate changing trends in prescribing practices among US haemophilia specialists during the past 22 years. Preference for high doses of factor (>40 units/kg) has increased during this period. Emicizumab prophylaxis has been prescribed for patients with and without HA inhibitors. Clinicians expect gene therapy to have value for some haemophilia patients.