Idelvion, a coagulation factor-albumin fusion protein product for use in children and adults with haemophilia B, has been approved by the US Food and Drug Administration.
Haemophilia B is a rare inherited bleeding disorder that causes blood not to clot normally because factor IX is deficient or defective. Idelvion provides replacement factor IX and is indicated for the control and prevention of bleeding episodes, management of bleeding following surgery, and as routine prophylaxis to reduce the frequency of bleeding episodes.
Idelvion (CSL Behring) potentially requires less frequent injections than unmodified factor IX when used for prevention because recombinant DNA technology has been used to link factor IX to the blood protein albumin, so that the product remains available longer in the circulation.
Idelvion (coagulation factor IX [recombinant], albumin fusion protein) is the second factor IX fusion protein product approved in the United States that has been modified to last longer in the blood. The first — Alprolix (coagulation factor IX [recombinant], Fc fusion protein) — was approved in March 2014. Less frequent injections are required with Alprolix because the factor IX molecule is linked to a protein fragment, Fc, found in antibodies, which makes the product last longer in circulation.
The safety and efficacy of Idelvion were evaluated in two multicentre studies involving 90 patients with haemophilia B, aged between 1 and 61 years. No safety concerns were identified in the studies. The most common side effect observed was headache.