Introduction:Prophylaxis with factor VIII (FVIII) concentrates in children with haemophilia A (HA) is current standard of care. The benefit of prophylactic treatment for adult HA patients is not commonly accepted. Aim:To investigate the benefit of prophylaxis over on-demand treatment in adult and elderly patients with severe or non-severe HA in a real-life setting. Methods: Data from 163 patients comprising 1202 patient-years were evaluated for 7.5 (±5.3) years. The effects on the annual bleeding rate (ABR, including spontaneous and traumatic bleeds) of treatment with a plasma-derived FVIII concentrate, the patient's age and disease severity were investigated. The effect of changing the treatment from on demand to continuous prophylaxis on the patients' ABRs was further analysed. Results: Prophylaxis had the greatest effect on the ABRs of patients of any age with severe or non-severe HA. The difference in ABR of all patients treated on demand (median 31.4; interquartile range (IQR) 27.6; N = 83) compared with those treated prophylactically (median 1.3; IQR 3.6; N = 122) was statistically significant (P < .05), even for patients with non-severe HA (median 8.4; IQR 15.5; N = 11) vs median 1.5; IQR 4.2 (N = 17), P < .05). Patients, aged up to 88 years, switching from on demand to continuous prophylaxis showed the lowest median ABR (1.1; N = 51) after their regimen change.Conclusion: Any (even low-frequency) prophylaxis results in lower ABR than on-demand treatment. Patients switching to prophylaxis benefitted the most, irrespective of age or HA severity. Prophylactic treatment-even tertiary-is the regimen of choice for patients of any age, including elderly patients, with severe or non-severe HA. K E Y W O R D Sadult and elderly patients, annual bleeding rate, effectiveness, haemophilia A, plasma-derived factor VIII concentrate, prophylaxis

We describe the results of the (to our knowledge) longest long-term noninterventional study so far performed to obtain real-life data on the treatment of hemophilia A patients with a single plasma-derived FVIII concentrate containing von Willebrand factor (pdFVIII; Haemoctin/Faktor VIII SDH Intersero). A total of 198 patients (146 in Germany and 52 in Hungary), of whom 160 had severe and 38 nonsevere hemophilia A, representing all age groups (0–88 years; mean ∼25 years at inclusion) were analyzed during prophylactic or on-demand treatment over 18 years (overall 1,418 patient-years; mean >7 years). pdFVIII was very effective and well tolerated. The mean annual bleeding rate, including spontaneous and traumatic bleeds, was considerably lower for patients treated prophylactically (mean 5.4; median 3.1) than for patients treated on demand (mean 26.1; median 21.9). Inhibitors were found in 13% (3/23) and high-titer inhibitors in 4% (1/23) of previously untreated patients with severe hemophilia A. Four previously treated patients with severe hemophilia A developed inhibitors, thereof three high-titer inhibitors (3.3 and 2.5 high-titer inhibitors in 1,000 patient-years). No unexpected adverse effect on the health of the patients, no pdFVIII-related thrombosis, thromboembolic event, or hypersensitivity reaction, and no suspected viral transmission related to pdFVIII were documented.