Long Acting rFactor lX: Interim Phase III data

Interim data from the open-label, international Phase III B-YOND extension trial in 116 patients with severe hemophilia B showed that no inhibitors have been reported with treatment of Alprolix. Patients in B-YOND received 1 of 3 prophylactic dosing options of Alprolix: 20-100 IU/kg Alprolix once weekly (weekly prophylaxis); 100 IU/kg Alprolix every 8-16 days or twice monthly (individualized prophylaxis); and personalized dosing if optimal prophylaxis could not otherwise be achieved (modified prophylaxis). Weekly prophylaxis with Alprolix led to an overall median annualized bleeding rate (ABR) of 2.28; individualized prophylaxis with Alprolix led to an ABR of 2.25; and modified prophylaxis with Alprolix led to an ABR 2.42 vs. 11.27 for on-demand treatment with Alprolix. The median overall ABR was 0 for children ages <6 years who received weekly prophylaxis with Alprolix (n=9). In children ages 6-12, the median overall ABRs were 2.65 for weekly Alprolix, 2.37 for individualized prophylaxis with Alprolix and 3.13 for modified prophylaxis with Alprolix. At the time of interim analysis, the median time on Alprolix during B-YOND was 27.6 months for adults and adolescents (n=93) and 47.7 weeks for children <12 years (n=23).

The most common adverse events reported included headache, common cold and vomiting for adults and adolescents and falls, common cold and seasonal allergy in children ages <12. An episodic treatment arm was also available for adult and adolescents. In B-YOND, patients can change treatment groups at enrollment and at any time during the study. B-YOND enrolled patients who completed the Phase III B-LONG or Kids B-LONG trials of Alprolix. From the beginning of B-LONG or Kids-B-LONG until the B-YOND interim data analysis, the cumulative median time on Alprolix was 171.6 weeks for adults and adolescents and 95.3 weeks for children ages <12. Data were presented at the National Hemophilia Foundation meeting in Dallas. ...