Jerzy Windyga MD, PhD, Oleksandra Stasyshyn MD, PhD, Toshko Lissitchkov MD, PhD, Vasily Mamonov MD, PhD, Margit Serban MD, PhD, Luminita Rusen MD, PhD, Bettina Ploder MSc, and Srilatha Tangada PhD
This phase 3, prospective, open-label, multicenter, continuation study (NCT01286779) investigated the use of a recombinant factor IX (FIX), nonacog gamma (BAX 326, RIXUBIS ® ) in patients with severe or moderately severe hemophilia B. The study population included 85 patients transitioning from a phase 1/3 pivotal study (NCT01174446), a pediatric study (NCT01488994), and 30 newly recruited patients, naïve to nonacog gamma. Patients received nonacog gamma as prophylaxis treatment (standard, modified or PK-tailored) or on-demand, as determined by the investigator. Treatment was assessed for safety, immunogenicity, hemostatic efficacy and consumption. In this study, after ≥100 exposure days, nonacog gamma resulted in no treatment-related serious adverse events, and no patients developed inhibitory antibodies to FIX. Nonacog gamma was efficacious at controlling bleeding episodes, with an 89.1% overall hemostatic efficacy rating of excellent or good, and 56% of bleeds resolved with one infusion. The annualized bleeding rate was considerably lower during prophylactic treatment (median ABR of 1.3 in 108 patients) than during on-demand treatment (median ABR of 16.5 in 13 patients). These results show that in previously treated patients and nonacog gamma-naïve patients, long-term use of nonacog gamma had acceptable safety and tolerability, and was efficacious as a prophylactic treatment for the management of bleeding episodes. NCT01286779, EudraCT: 2010-022726-33