Spark reports new Factor VIII activity data for hemophilia A gene therapy

Spark Therapeutics Inc. (NASDAQ:ONCE) reported new Phase I/II data showing that the highest tested dose of hemophilia A gene therapy SPK-8011 led to lower than expected Factor VIII activity levels in two patients.

Spark's open-label, international Phase I/II trial has enrolled 12 patients to receive one of three doses of a single IV infusion of SPK-8011: 5x10¹¹ (n=2), 1x10¹² (n=3) and 2x10¹² (n=7) vector genomes per kg (vg/kg)...