AlphaNine SD for Hemophilia B

AlphaNine SD is an injectable, high purity, plasma-derived form of coagulation factor IX, marketed by Grifols to prevent and control bleeding in adults with hemophilia B. It was approved for use by the U.S. Food and Drug Administration (FDA) in 1996.

How AlphaNine works

People who have hemophilia B have missing or defective coagulation factor IX, an important player in the coagulation cascade. The cascade is a series of chain reactions that culminate in the formation of fibrin, the protein that clumps to form a clot when a blood vessel is injured. Without sufficient levels of functional factor IX, clots are slower to form and bleeding episodes more frequent and prolonged, especially in the joints and soft tissues.

Called a factor IX replacement therapy, AlphaNine SD replaces the deficient or missing factor IX to improve clotting and prevent or lessen excessive or uncontrolled bleeding.

AlphaNine in clinical trials

AlphaNine SD was approved by the FDA more than 20 years ago based on clinical trials that showed it effectively controlled bleeding in 13 patients undergoing surgery.  Its safety profile was positive and, importantly, AlphaNine SD administration did not lead to an increased the risk of unwanted blood clots — a problem that can arise in patients on coagulant factor replacement therapy.

More recent studies re-affirm that AlphaNine SD is a safe and effective substitution therapy for hemophilia B patients. One, a multicenter and non-randomized trial of 25 patients, ages 12 or older — with results published in a 2011 issue of the journal Haemophilia — showed that AlphaNine SD controlled close to 90 percent of bleeding episodes after the first infusion, with no adverse events attributed to the medication’s use.

Additional information

AlphaNine SD is a human biologic product, made from plasma (clear portion of the blood) that is purified, treated with detergents, and filtered to remove contaminants, including viruses. However, there is always a small chance of viral contamination.

Factor IX therapies have been associated with abnormal clotting (thrombosis).  The purification process used to make AlphaNine SD makes the occurrence of blood clots rare, but it is still important to strictly adhere to the recommended dose to minimize thrombosis risk.

AlphaNine SD is not approved for use in children ages 16 or younger, or for use as prophylaxis (routine administration to prevent bleeding).


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