FDA approves Hemlibra for hemophilia A
The FDA today approved emicizumab-kxwh to prevent or reduce the frequency of bleeding episodes among patients with hemophilia A who have developed factor VIII inhibitors.
“Reducing the frequency or preventing bleeding episodes is an important part of disease management for patients with hemophilia,” Richard Pazdur, MD, acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research and director of the FDA’s Oncology Center of Excellence, said in a press release. “Today’s approval provides a new preventative treatment that has been shown to significantly reduce the number of bleeding episodes in patients with hemophilia A with factor VIII inhibitors. In addition, patients treated with Hemlibra reported an improvement in their physical functioning.”
Patients with hemophilia A — an inherited blood-clotting disorder that primarily occurs in males — lack a gene that produces factor VIII, a protein the enables blood clotting. Patients with hemophilia A often experience serious bleeds, especially in their joints, which can be severely damaged.
Some patients develop a factor VIII inhibitor, which makes currently available treatments less effective.
Emicizumab-kxwh (Hemlibra, Genentech) — a first-in-class therapy that is given via a weekly subcutaneous injection for bleeding prophylaxis — bridges other factors in the blood to restore clotting in patients.
The agency based their decision on data from two clinical trials.
The first trial included 109 males aged at least 12 years who had hemophilia A and factor VIII inhibitors. In a randomized portion of the trial, researchers compared emicizumab-kxwh with no prophylaxis among 53 patients who had been previous treated with on-demand therapy with a bypassing agent. Patients assigned prophylaxis with emicizumab-kxwh experienced an average of 2.9 treated bleeding episodes a year, compared with 23.3 bleeding episodes among those in the control arm, representing an 87% reduction.
Patient-reported quality-of-life metrics from the trial showed emicizumab-kxwh improved hemophilia-related symptoms and physical functioning.
The second trial included 23 males aged younger than 12 years, all of whom received emicizumab-kxwh. Eighty-seven percent of patients did not experience a bleeding episode that required treatment.
Adverse events associated with emicizumab-kxwh included injection site reactions, headache and arthralgia.
Emicizumab-kxwh’s label includes a boxed warning alerting clinicians and patients that thrombotic microangiopathy and thromboembolism occurred in some patients who received an activated prothrombin complex concentrate to treat bleeds for 24 or more hours.
Emicizumab-kxwh also received priority review and breakthrough therapy and orphan drug designations for this indication.