Pediatric patients with hemophilia A with factor VIII (FVIII) inhibitors have not seen lower annualized bleeding rates (ABRs) with current standard treatments, highlighting a need for novel, effective treatments, according to research published in Pediatric Blood & Cancer.
Pediatric patients with hemophilia A and FVIII inhibitors can face frequent, difficult to treat bleeding episodes, with a consequent higher risk for severe bleeds and the implications thereof, compared with patients with hemophilia without FVIII inhibitors. The condition is typically diagnosed in patients aged 3 years or younger, which can further complicate treatment.
Two frequently used treatments in this setting are immune tolerance induction, which involves FVIII infusion to remove inhibitors, and bypassing agents, which may help to manage bleeding incidents prophylactically. However, neither treatment assures a positive outcome, highlighting a need for novel treatments in this area.
In an effort to describe the clinical characteristics of PwHA, which may, in turn, help inform the development and use of novel treatments, researchers conducted a multicenter, noninterventional study of patients with or without FVIII inhibitors. The findings from data collection on bleeding events, treatment, safety, and health-related quality of life (HRQoL) among children with hemophilia A and FVIII inhibitors treated at local clinical practices were outlined in the present paper.
Overall, data from 24 patients were included in this study. The median patient age was 7.5 years (range, 2-11), 12 (50%) had previously received immune tolerance induction, and the mean number of bleeds in the preceding 6 months was 7.5. In addition, 10 (41.7%) patients were treated in an episodic manner and 14 (58.3%) were treated prophylactically.
In the episodic treatment group, 121 of 185 bleeding incidents were treated with activated prothrombin complex concentrate (aPCC), sometimes in conjunction with recombinant activated FVII (rFVIIa). ABRs for treated vs all bleeds were 19.4 and 32.7, respectively.
In the prophylaxis group, 101 of 186 (54.3%) bleeding incidents were treated with aPCC and/or rFVIIa. ABRs for treated vs all bleeds were 18.5 and 33.1, respectively. Of the 92.9% of patients in the prophylactic cohort who were prescribed aPCC, only 50% of adhered to their medication regimen.
Hemarthrosis (12.5%), mouth hemorrhage (12.5%), and viral upper respiratory tract infection (12.5%) were the more frequently noted serious and nonserious adverse events.
HRQoL was low at baseline and maintained a steady level throughout the study period.
“These children experienced a high treatment burden with numerous weekly infusions and notable incidence of hemarthrosis, as well as concomitant impairments in HRQoL, suggesting that there remains a substantial unmet need for improved treatment options in this patient population,” the authors concluded.
Disclosures: Some authors have declared affiliations with or received funding from the pharmaceutical industry. Please refer to the original study for a full list of disclosures.
Oldenburg J, Shima M, Kruse-Jarres R, et al. Outcomes in children with hemophilia A with inhibitors: Results from a noninterventional study. Pediatr Blood Cancer. Published online August 9, 2020. doi:10.1002/pbc.28474