Eptacog Beta Effectively Treats Bleeds in Children With Hem A or B
Eptacog beta was safe and almost 100% effective at stopping bleeds within 24 hours in boys ages 12 and younger with hemophilia A or B, according to final data from the Phase 3 PERSEPT 2 trial.
According to researchers, this bypass agent may be an important option for patients and caregivers in treating bleeding episodes in children.
The study, “Eptacog beta efficacy and safety in the treatment and control of bleeding in paediatric subjects (<12 years) with haemophilia A or B with inhibitors,” was published in the journal Haemophilia.
Hemophilia is caused by a deficiency in certain blood clotting factors necessary to prevent excessive bleeding. People with hemophilia A lack clotting factor VIII (FVIII), and those with hemophilia B have a shortage of factor IX (FIX).
Replacement therapy is a current standard of care for both types of hemophilia, providing patients with a version of the clotting factor they are missing. However, regular treatment can lead to the development of neutralizing antibodies, or inhibitors, against these factors that lower their effectiveness.
Eptacog beta is a bypassing agent designed to enhance blood clotting in hemophilia patients with inhibitors against FVIII or FIX. It is approved for those ages 12 and older in the U.S. and sold under the brand name Sevenfact.
The open-label Phase 3 PERSEPT 2 trial (NCT02448680) tested the safety and on-demand efficacy of this bypassing agent in young children with hemophilia A or B and inhibitors.
It enrolled 25 boys, between the ages of 1 and 11; among them, 23 had hemophilia A and two had hemophilia B. Twelve boys were randomly assigned to an initial dose of eptacog beta at 75 micrograms per kilogram (mcg/kg), and 13 to a higher 225 mcg/kg dose. Patients switched between these dosing regimens every three months.
Parents or caregivers were instructed to start an intravenous infusion at the assigned dose as soon as possible after a bleeding episode. Assessments of efficacy and the need for an additional, 75 mcg/kg dose were made three hours after treatment for those receiving the lower dose, and after nine hours for those in the higher dose group.
Bleeding episodes were characterized as mild, moderate, or severe. The trial’s primary goal was to successfully treat mild or moderate bleeding episodes within 12 hours of an infusion.
Boys in the lower dose group experienced 239 mild or moderate bleeds, while those in the high dose group reported 307 episodes. Most (92%) bleeds were treated at home.
A similar proportion of successful treatments was reported in the lower and higher dose groups at 12 hours (65.4% vs. 60.3%) and 24 hours (97.4% vs. 98%). Similar results were also found when data from both dosing regimens were combined.
Treatment effectiveness in these younger patients was lower than that seen in adolescents and adults treated at the same doses in the Phase 3 PERSEPT 1 trial (NCT02020369). Low-dose efficacy at 12 hours after initial treatment in PERSEPT 1 was 84.9% and 93.2% at high dose.
Researchers noted that a lack of parent or caregiver clarity regarding the end of a bleeding episode, an issue in treating children with hemophilia, “would contribute towards conservative estimates of treatment success proportions at the 12-[hour] timepoint.”
Bleeding into the joints accounted for 68% of the 546 total mild or moderate bleeding episodes, and recurrent episodes in the same joint represented 19.9% of all joint bleeds. A median of three 75 mcg/kg doses and two 225 mcg/kg doses was needed to control bleeding.
Parents or caregivers rated the proportion of ‘excellent’ or ‘good’ bleeding episode treatments to be 64.3% at 12 hours and 97.6% at 24 hours.
Using a visual analog scale (VAS), patients or caregivers rated pain relief after 12 hours as achieved for 92.8% of bleeds occurring in the 75 mcg/kg dose group and 90.8% of those in the 225 mcg/kg dose group. The mean percent decrease in VAS pain scores 12 hours after treatment was 70.9% with the low dose and 64.5% with the high dose.
Eptacog beta was well tolerated, with no reports of abnormal blood clotting events, allergic reactions, inhibitors, or treatment-related side effects.
“Both eptacog beta [doses] (75 and 225 μg/kg) provided safe and effective treatment and control of bleeding by 24 [hours] to the trial subjects,” the scientists wrote. “As such, eptacog beta potentially offers an important therapeutic option to patients, caregivers and health care providers” to treat bleeding episodes.