FDA approves Hemlibra for hemophilia A without factor VIII inhibitors
The FDA expanded the approval emicizumab-kxwh to include routine prophylaxis to prevent or reduce the frequency of bleeding episodes among patients with hemophilia A without factor VIII inhibitors.
Emicizumab-kxwh (Hemlibra, Genentech) — a bispecific factor IXa- and factor X-directed antibody — is now indicated for patients with hemophilia A with or without factor VIII inhibitors. The antibody can be self-administered subcutaneously once weekly, every 2 weeks or every 4 weeks.
The FDA based the latest approval on results from the phase 3 HAVEN 3 and HAVEN 4 studies, which assessed emicizumab-kxwh among adults and adolescents aged 12 years or older.
In the HAVEN 3 study, researchers assigned 36 patients to once-weekly emicizumab-kxwh, 35 patients to emicizumab-kxwh every 2 weeks and 18 patients to no prophylaxis.
Results showed a 96% (95% CI, 92.5-98) reduction in treated bleeds among those treated weekly and a 97% (95% CI, 93.4-98.3) reduction among those treated every 2 weeks.
In the HAVEN 4 study, researchers assessed dosing every 4 weeks among 36 patients without factor VIII inhibitors and five with factor VIII inhibitors. All patients had previously received factor VIII or bypassing agents, on-demand or as prophylaxis.
Results showed 56.1% (95% CI, 39.7-71.5) of patients experienced zero treated bleeds and 90.2% (95% CI, 76.9-97.3) experienced three or fewer treated bleeds.
“Many preventative treatment options for people with hemophilia A without factor VIII inhibitors require intravenous infusions several times a week. Even then, people can still experience bleeds, and there has been a need for more treatment options,” Michael Callaghan, MD, hematologist at Children’s Hospital of Michigan, said in a company-issued press release. “The approval of Hemlibra is an important advancement for the entire hemophilia A community, as we now have a new class of medicine for the first time in nearly 20 years. Hemlibra can reduce bleeds, and it offers a new subcutaneous administration once weekly, every 2 weeks or every 4 weeks.”
In both studies, the most common adverse reactions occurring in 10% or more of treated patients (n = 391) included injection site reactions (n = 85), headache (n = 57) and arthralgia (n = 59).
“Today’s approval of Hemlibra reflects our commitment to groundbreaking science and the development of medicines with the potential to redefine the standard of care,” Sandra Horning, MD, chief medical officer and head of global product development at Genentech, said in the release. “Hemlibra is now the only FDA-approved medicine for people with hemophilia A with and without factor VIII inhibitors, based on the efficacy and safety profile demonstrated across four pivotal studies.”
The FDA granted breakthrough therapy designation and priority review to emicizumab-kxwh for hemophilia A without factor VIII inhibitors.