Results of a prospective observation on the use of a coagulation factor concentrate VIII concentrate (Octanate®) for the induction of immunological tolerance in patients with an inhibitory form of hemophilia A

Relevance. Immune tolerance induction (ITI) is the only approach proven to eradicate inhibitors in hemophilia A patients. ITI with Octanate® (human VWF-stabilized FVIII) has been shown to be effective at eradicating inhibitors, even in poor-prognosis patients. Here we report interim data from two observational, prospective studies on the use of Octanate® for ITI in patients in Russia. Purposes of research. The primary objective was to assess the efficacy of ITI. Secondary objectives included assessment of time to ITI success and inhibitor eradication. Patients and methods. Patients of any age with any severity of hemophilia A and a FVIII inhibitor 0.6 BU/mL were eligible. The ITI regimen was at the discretion of the treating physician. Results. The analysis included 73 patients. ITI outcomes were assessed in 63 patients who had completed the study, of whom 56 (89 %) had 1 poor prognostic factors. Inhibitor eradication was achieved by 77.1 % (37/48) of primary ITI patients and 71.4 % (45/63) of all patients, in a median of 2.4 months (range – 0.0–27.4) for both groups. Complete success was achieved by 72.9 % (35/48) of primary ITI patients in a median of 8.9 months (range – 2.4–28.0) and 66.7 % (42/63) of all patients in a median of 10.5 months (range – 2.4–28.0). No relapses were reported after complete or partial ITI success. Of the patients with 1 poor prognostic factors, 67.9 % achieved inhibitor eradication and 62.5 % complete success. Conclusions. ITI with Octanate® in a real-world setting showed rapid and sustained success, even in patients with poor prognostic factors.