The Food and Drug Administration has approved the first hemophilia B treatment designed to decrease frequency of injections to prevent the excessive bleeding the clotting disorder causes.
 

The medicine, Alprolix (all-PRO'licks), is for preventing or shortening bleeding episodes in adults and children with hemophilia B, the second-most common type. It affects about 3,300 Americans, mostly males.

Manufacturer Biogen Idec Inc. of Cambridge, Mass., calls it the first major advance for hemophilia B in almost two decades.

The disorder, usually inherited, is due to a genetic defect that causes deficiency of clotting proteins called Factor IX. Severity varies, but patients bleed longer than normal after cuts or surgery, and can have significant, painful internal bleeding. That can damage eyes and joints over time. After severe injuries, patients can bleed to death.