Hemophilia A Drug Successful in Phase 3 Trial

Hemophilia Reports, June 2015, Volume 2, Issue 2

A new drug from Baxter has been found safe and efficacious for hemophilia A patients aged 12 years or older in a phase 3 trial.

BAX 855, an extended half life recombinant factor VIII treatment for hemophilia A, is safe and efficacious, according to findings presented at the 8th Annual Congress of the European Association for Hemophilia and Allied Disorders in Helsinki, Finland.

The drug is based on Advate, which is a recombinant anti-hemophilic factor used for perioperative management, standard prophylaxis to prevent or reduce bleeding episode frequency, and control and prevent bleeding episodes in hemophilia A patients. Advate has 11 years of real world patient experience, the company statement noted.

The phase 3 trial encompassed 137 previously untreated hemophilia A patients aged 12 years or older. The patients were assigned either to the twice weekly prophylaxis group or on demand treatment. Participants enrolled in the twice weekly prophylaxis group experienced a 95 percent reduction in median annualized bleeding rate (ABR) compared to those in the on demand treatment arm. Nearly all (96 percent) or bleeding episodes were controlled with one or 2 infusions at a median dose, and the treatment was rated excellent or good in 96.2 percent of all episodes. Forty percent of patients in the prophylactic group, which included 101 participants, experienced no bleeds.

These findings were aligned with the December 2014 Baxter submission of approval of BAX 855 to the US Food and Drug Administration. The phase 3 trial results also supported the phase 1 findings, in which BAX 855 pharmacokinetics offered a 1.4-1.5 fold extended half life compared to Advate with a median infusion internal of 3.6 days.

“These pivotal trial results provide evidence to support the efficacy profile of BAX 855 in controlling, preventing, or reducing the frequency of bleeding episodes when administered prophylactically twice weekly,” John Orloff, MD, vice president and global head of research and development for Baxter BioScience said in a press release. “Our goal with BAX 855 is to extend the interval between infusions while maintaining a similar efficacy profile to Advate.”

There were no patients in the study who developed inhibitors to BAX 855. The researchers reported no treatment related serious adverse events, including hypersensitivity. However, 7 adverse reactions in 6 patients were reported, such as headache, diarrhea, nausea, and flushing.

Baxter has ongoing trials for hemophilia A patients under the age of 12 years. Once the pediatric study is completed, the company plans to file for marketing authorization with the European Medicines Agency in August 2016.