Spark, Pfizer Record Sustained Factor IX Activity Levels In SPK-9001 Trial

(RTTNews) - Spark Therapeutics (ONCE) and Pfizer Inc. (PFE) Monday announced that the ongoing Phase 1/2 clinical trial of SPK-9001 for the treatment of patients with hemophilia B had discontinued routine infusions of factor IX concentrates and shown sustained steady-state factor IX activity levels.

The open-label, non-randomized and multicenter study has recorded no serious adverse events, thrombotic events or factor IX inhibitors. The study had 11 participants.

Hemophilia is a rare genetic bleeding disorder that causes the blood to take a long time to clot. This is due to deficiency in one of several blood clotting factors and is almost exclusively found in males.

The overall annualized bleeding rate was reduced by 97 percent to a mean of 0.3 annual bleeds, compared to a mean of 10.5 bleeds annually before SPK-9001 administration. Overall annualized infusion rate was reduced 99 percent to a mean of 0.8 annual infusions, compared to a mean of 62.5 infusions per year before SPK-9001 administration.