Biogen and Swedish Orphan Biovitrum have started two paediatric trials of the companies' long-lasting recombinant Factor VIII and Factor IX Fc fusion proteins (rFVIIIFc and rFIXFc) in haemophilia A and B.
The open-label, multicentre studies are designed to evaluate the safety, pharmacokinetics and efficacy of rFVIIIFc and rFIXFc in previously treated children under the age of 12 years with severe haemophilia A or B.
Glenn Pierce, Biogen's haemophilia therapeutic area chief medical officer and global medical affairs senior vice president, said: "The paediatric clinical trials are an important complement to the ongoing adult studies and further demonstrate our commitment to develop new treatments for the haemophilia community."
The first patients have already been dosed in the rFIXFc paediatric study, and the rFVIIIFc paediatric study is now actively recruiting patients.
The Kids A-LONG study will evaluate rFVIIIFc in the prevention and treatment of bleeding episodes in previously treated paediatric patients with haemophilia A.
The frequency of inhibitor development over an approximately 26-week treatment period and at least 50 exposure days to rFVIIIFc are the primary outcome measures. The number of annualised bleeding episodes and assessments of response to treatment over the same time period are the secondary outcome measures of the paediatric study.
Similarly, rFIXFc will be evaluated in the Kids B-LONG study for the prevention and treatment of bleeding episodes in previously-treated paediatric patients with haemophilia B.
The primary outcome measure is the frequency of inhibitor development over an approximately 50-week treatment period and at least 50 exposure days to rFIXFc.
Secondary outcome measures include the number of annualised bleeding episodes and assessments of response to treatment over the same time period.
Clinical development head at Swedish Orphan Biovitrum, An van Es-Johansson, said: "With these studies, we extend the clinical development of rFVIIIFc and rFIXFc to address a broader patient population including children with haemophilia."