Sobi Swedish Orphan Biovitrum and its partner Biogen have announced the publication of the interim results of a clinical study that showed low rates of bleeding in individuals with hemophilia treated with rFVIIIFc (fusion protein, consisting of the recombinant factor VIII linked to the Fc domain of human IgG1) in prophylaxis regimen at extended intervals of administration. Patients who completed the Phase III studies A-LONG and Kids A-LONG were enrolled the Phase III ASPIRE. The results obtained to date indicate that the majority of study participants ASPIRE maintained or extended intervals of drug administration than studies A-LONG and Kids A-LONG. At the time of the interim analysis, the median of treatment in the study ASPIRE was 80.9 weeks in the adult and adolescent participants who completed the A-LONG study, and 23.9 weeks in those in children who completed the study Kids A-LONG. The primary endpoint of ASPIRE is the development of inhibitory antibodies, whose onset is not however been reported in any of the groups. For the period of analysis considered interim ASPIRE, the number of bleeding on an annual basis (annualized bleeding rates or ABR) in adults and adolescents in arms prophylaxis regimen customized, changed weekly and were 0.66, 2 .03 and 1.97. Even children in prophylaxis regimen custom were recorded lower rates of bleeding, with an overall median of 0.0 ABR in children under 6 and 1.54 in children aged between 6 and 12 years. These findings are consistent with those obtained in the Phase III studies A-LONG and Kids A-LONG. In addition to the results of efficacy and safety, the publication also contains data on the frequency of infusions in prophylaxis regimen throughout the period considered from the end of the study A-LONG. Of adults and adolescents treated in prophylaxis and who continued the study (n = 128), 72% maintained the same dosing interval, 22% of those stretched between administration and the next, while 6% has reduced intervals. Participants in the extension study could change the treatment group at any time.