New Exploratory Analysis Results from Fitusiran, an Investigational RNAi Therapeutic for the Treatment of Hemophilia and Rare Bleeding Disorders

We reported new results from an exploratory analysis of our Phase 1 study with fitusiran, an investigational RNAi therapeutic, in patients with hemophilia A or B with or without inhibitors at the 10th Annual Congress of the European Association of Haemophilia and Allied Disorders (EAHAD) held February 1 – 3, 2017 in Paris, France.

New analyses examined 21 total bleed events in 41 patients after being treated with fitusiran and achieving >75% antithrombin lowering. Results showed that dosing of agents was generally within the normal dose range for replacement Factor VIII and Factor IX as well as for the bypassing agent rFVIIa, while at the lower end of the dose range for the bypassing agent aPCC. Importantly, treatment of all breakthrough bleed events resulted in successful hemostasis without any thromboembolic events.

Further, results presented from stability studies of fitusiran support a greater than two-year shelf life at room temperature storage conditions and demonstrated resistance to thermal stress that may occur during real world storage and handling of the product. We are encouraged by these results, as the robust stability profile of fitusiran could enable convenient transportation and storage, including in parts of the world where cold chain delivery is a challenge.

We believe fitusiran represents an innovative and differentiated approach to the treatment of hemophilia and other rare bleeding disorders, with the potential to transform disease management and improve the lives of patients.