Safety of Recombinant Human Factor IX, Nonacog Alfa, for Usual Use In Pediatric Patients: Results From a Prospective Registry of European Hemophilia B Patients.

To evaluate the long-term safety of nonacog alfa in pediatric hemophilia B patients during usual use.

An open-label, multicenter, prospective registry was conducted in 9 European countries to evaluate the safety of nonacog alfa in patients with hemophilia B in a usual-use setting. The registry was initiated in March 2002, with a period of enrollment of 7 years. Patients had received at least 1 dose of the original formulation of BeneFIX or a newer, reformulated version of the product. Of 218 patients enrolled in the registry, 66 (30.3%) were pediatric patients <18 years of age.

A total of 41 (62.1%) of the pediatric patients completed the registry per protocol. Seven events of special interest (ESIs) occurred in 6 (9%) patients. Allergic reaction was the sole ESI in 2 patients, lack of drug effect/low FIX recovery occurred in 3 patients, and 1 patient had an allergic reaction and developed a factor IX inhibitor. Two (3.0%) patients withdrew from the registry due to an ESI and/or a serious adverse event. Both were patients who developed an allergic reaction and one was the patient who also developed an inhibitor.

The events reported for pediatric patients participating in this long-term prospective study demonstrated an acceptable safety profile for nonacog alfa in the pediatric population. The events did not differ in type, frequency, or severity from those previously observed in pediatric hemophilia B patients treated with nonacog alfa.

Rendo:Pfizer: Employment. Keeling:Boehringer-Ingelheim:; Bayer: Membership on an entity's Board of Directors or advisory committees, lecture fee. Kollmer:Pfizer: Employment. Baumann:Pfizer: contract. Charnigo:Pfizer: Employment.