Immune Tolerance Induction With a Recombinant Factor VIII Fc in Haemophilia A: Data From a Chart Review Study.

OBJECTIVE

To report data from an ITI chart review study (NCT03951103) for first-time and rescue ITI with recombinant factor VIII Fc fusion protein (rFVIIIFc) in persons with haemophilia A.

METHODS

Retrospective and prospective real-world data are reported from a non-interventional, multicentre study of patients who had been or were currently being treated with rFVIIIFc ITI. ITI treatment outcome (defined by investigators) and regimens are reported.

RESULTS

Forty-one patients from 16 sites were included. First-time ITI was used in 24 patients; 16 had an ITI outcome at study end. Thirteen patients (81.3%) had ITI success, and three had failure. Median (range) rFVIIIFc consumption was 300 (61-2800) IU/kg/week, and most (70.8%) used ≤ 300 IU/kg/week. The vast majority of patients (87.5%) received less than daily ITI. Rescue ITI was used in 17 patients; 16 had an ITI outcome at study end. Eight patients (50.0%) had ITI success/partial success, seven had failure, and one withdrew early. Median (range) rFVIIIFc consumption was 536 (98-1435) IU/kg/week; 35.3% used ≤ 300 IU/kg/week and 52.9% used > 500 IU/kg/week. Most patients (64.7%) received daily ITI.

CONCLUSION

ITI with rFVIIIFc is likely to be successful in first-time ITI patients and is an effective option for those who have previously experienced ITI failure.

TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03951103.