In Australia, patients with hemophilia A or B demonstrated high rates of adherence to prophylactic extended half-life (EHL) factor VIII or IX concentrates, according to a retrospective study. In addition, over 50% of patients reported no spontaneous bleeding events during a 1-year period.
The retrospective study, which was published in the journal Haemophilia, analyzed data from 174 persons with hemophilia (PWH), including 115 patients with hemophilia A and 59 with hemophilia B. Patients were enrolled in the Australian Bleeding Disorders Registry database, which includes data from 18 Hemophilia Treatment Centers.
Among patients with hemophilia A, 93.1% had severe disease, 44.3% were adults, and 18.3% of patients had a history of bleeding in target joints. In the hemophilia B group, there were 88.1% of patients with severe disease, 42.4% were adults and 22.1% had a history of bleeding in target joints.
EHL treatment was adjusted in 12% of adults and 31% of pediatric patients with hemophilia A. For adults, this was weight-based or due to the patient choice or the occurrence of bleeding. For pediatric patients, this was primarily pharmacokinetic-based or due to bleeding events. Among patients with hemophilia B, 5% of adults and 9% of pediatric patients had a dose adjustment for similar reasons as patients with hemophilia A.
During a 1-year period, patients with hemophilia A or B demonstrated an adherence to their EHL treatment of 85.7% and 87.2%, respectively.
No spontaneous bleeds were reported by 63.5% of patients with hemophilia A and 64.4% of patients with hemophilia B. The bleeding events occurred in the joints among 78.6% of patients with hemophilia A and 57.1% with hemophilia B. The most common site of spontaneous bleeding was the ankles.
Spontaneous bleeding was significantly associated with nonadherence to EHL therapy (coefficient, 1.66; 95% CI, 0.653-2.671; P =.02) and a past history of target joint bleeds (coefficient, 1.56; 95% CI, 0.702-2.436; P =.01).
“This 12-month study of EHL usage in Australia has demonstrated excellent treatment adherence and bleeding outcomes,” the authors concluded in their report.
George C, Parikh S, Carter T, et al. Evaluation of treatment and outcome for patients with haemophilia A and haemophilia B on extended half-life (EHL) factor products: A 12-month data analysis. Haemophilia. Published online August 11, 2023. doi: 10.1111/hae.14842