Efficacy, safety and tolerability of recombinant factor VIII (REFACTO®) in patients with haemophilia A: interim data from a postmarketing surveillance study in Germany and Austria

• Published in: Haemophilia : the official journal of the World Federation of Hemophilia Vol. 13; no. 2; pp. 131 - 143
• Main Authors: POLLMANN, H., EXTERNEST, D., GANSER, A., EIFRIG, B., KREUZ, W., LENK, H., PABINGER, I., SCHRAMM, W., SCHWARZ, T. F., ZIMMERMANN, R., ZAVAZAVA, N., OLDENBURG, J., KLAMROTH, R.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01-03-2007
• Subjects: Adolescent; Adult; Adverse Drug Reaction Reporting Systems; Aged; Austria; Child; Child, Preschool; Coagulants - adverse effects; efficacy; Factor VIII - adverse effects; Germany; haemophilia A; Hemophilia A - drug therapy; Humans; Infant; Infant, Newborn; Male; Middle Aged; postmarketing surveillance; Prospective Studies; recombinant factor VIII; REFACTO; Risk Management; tolerability; Treatment Outcome
• ISSN: 1351-8216; 1365-2516
• DOI: 10.1111/j.1365-2516.2006.01416.x

An open‐label, multicentre, postmarketing surveillance study conducted in Germany and Austria with recombinant factor VIII (REFACTO®) has enrolled 217 patients (mean age 26.3 years) from 38 haemophilia centres during the first 4.8 years. Most patients (188/217; 86.6%) had severe to moderately severe haemophilia A, of whom 153 completed sufficient diary information for the main efficacy analysis. These 153 patients experienced a median of 6.6 (interquartile range 1.4–18.6) bleeding episodes per year. Patients treated with prophylaxis experienced a median of 4.4 (1.1–9.3) bleeds per year, while patients treated on‐demand experienced a median of 22.8 (11.3–29.0) bleeds per year. Overall, most physicians (41/43 [95.3%]) were ‘very satisfied’ or ‘satisfied’ with the efficacy of REFACTO in the treatment of bleeding episodes. A total of 137 non‐serious adverse events have been reported in 52/217 patients (24.0%) to date. In addition, 129 serious adverse events in 87 patients (40%) were reported, including 41 cases of ‘less than expected therapeutic effect’ (LETE). Of these, 39 LETE cases were reported in one centre; however, patients in this centre experienced considerably fewer bleeding episodes per year than patients outside this centre. Overall, six patients (2.8%) have developed de novo inhibitors, three of which were considered high titre. Four of these patients were at high risk (0–50 exposure days [ED]) of inhibitor formation, one was at intermediate risk (51–100 ED) and one was at low risk (>100 ED). These results emphasize the benefit of postmarketing surveillance and, overall, this study confirms the efficacy, safety and tolerability of REFACTO in the treatment of patients with haemophilia A.