CSL Behring’s investigational long-acting fusion protein linking recombinant coagulation factor IX with recombinant albumin (rIX-FP) might be able to be infused at longer intervals of every 14 days, says new research, in people with hemophilia B.
MedicalResearch.com Interview with:
Dr. Elena Santagostino, MD PhD
Angelo Bianchi Bonomi Hemophilia and Thrombosis Center
Ca’ Granda Foundation
Maggiore Hospital Policlinico, Milan, Italy
Medical Research: What is the background for this study? What are the main findings?
Dr. Santagostino: Two of our abstracts presented at the 57th ASH Annual Meeting are part of the PROLONG-9FP clinical program evaluating the efficacy and safety of CSL Behring’s investigational long-acting fusion protein linking recombinant coagulation factor IX with recombinant albumin (rIX-FP). The first is an oral presentation on results from two Phase III studies and an ongoing extension study of rIX-FP for routine prophylaxis in previously-treated people with hemophilia B.
The two Phase III studies included adolescents and adults (ages 12 to 61) treated with dosing intervals of up to 14 days for 12 to 18 months, and children (ages 1 to 11) who received seven-day prophylaxis treatment for approximately 12 months. Overall, the median annualized spontaneous bleeding rate (AsBR) was 0.00 for all treatment intervals. The extension study is examining longer treatment intervals, including 10- and 14-day intervals in patients younger than 12 and more prolonged treatment intervals in patients older than 18, and so far has reported favorable long-term tolerability with no serious adverse reactions such as the development of inhibitors to factor IX or antibodies to rIX-FP.
A second abstract reported on a surgical sub-study in these trials found that a single pre-operative dose of rIX-FP maintained hemostasis during surgery with responses rated by investigators as “excellent” or “good.” Oven a 14-day perioperative period, patients needed six or seven infusions, and none developed inhibitors to factor IX or antibodies to rIX-FP.
Medical Research: What should clinicians and patients take away from your report?
Dr. Santagostino: These latest results are promising and confirm the data we saw in our pivotal studies, with prolonged dosing intervals of up to 14 days with rIX-FP for routine prophylaxis. This is an important attribute for patients who require a prophylactic regimen but don’t want treatment to disrupt their active lives.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Santagostino: rIX-FP has been developed with a pharmacokinetic profile that allows for less frequent dosing. Through the ongoing extension study, we are continuing to evaluate longer treatment intervals and the potential impact on preventing bleeding in select patients.