Real-World Unmet Needs of Patients With Haemophilia A and Haemophilia B With or Without Inhibitors: End-of-Study Results From the explorer6 Non-Interventional Study.

Introduction: Haemophilia is associated with high disease and treatment burdens. Prospective evaluation of data from patients with haemophilia helps understand and define unmet needs, optimise treatment and improve healthcare outcomes.

Aim: To present end-of-study data from explorer6 (NCT03741881), a prospective, non-interventional study across multiple countries in patients with haemophilia (haemophilia A or B without [HA or HB] or with inhibitors [HAwI or HBwI]).

Methods: Patients ≥12 years old with severe HA, severe/moderate HB or HAwI/HBwI of any severity were treated according to the local standard of care (SoC). The number of bleeding episodes from enrolment up to a maximum of 115 weeks, physical activity based on data collected by a wrist-worn physical activity tracker, target joints and Haemophilia Joint Health Score (HJHS) measurements were assessed.

Results: A total of 231 patients across 33 countries were enrolled. The mean annualised bleeding rate (ABR) (standard deviation) for treated bleeding episodes was investigated for patients receiving prophylaxis (HA: 4.7 [5.9]; HB: 2.2 [3.0]; HAwI: 10.3 [8.5]; HBwI: 12.4 [14.1]) and those receiving on-demand (OnD) treatment (HA: 21.5 [17.7]; HB: 10.5 [8.6]; HAwI: 15.2 [14.8]; HBwI: 9.3 [13.3]). Physical activity levels were lowest among patients with HBwI. Target joints were similar among haemophilia types and treatments. Overall, mean and median HJHS total scores were lower for patients receiving prophylaxis compared with OnD treatment.

Conclusion: The explorer6 study assessed a large haemophilia patient population in a real-world setting across 33 countries. The results indicate that an unmet need remains among patients receiving OnD treatment and those with inhibitors.

Trial registration: ClinicalTrials.gov identifier: NCT03741881.