Interim data from phase III study presented at ASH 2022 show Hemlibra achieved meaningful bleed control in infants from birth

The study shows Hemlibra (emicizumab-kxwh) achieved meaningful bleed control with a favorable safety profile in infants (up to 12 months) with severe hemophilia A without factor VIII inhibitors: 77.8% of participants did not have any bleeds that required treatment and 42.6% did not have any treated or untreated bleeds at all. These results help support the use of Hemlibra in this population, in which it is already approved in many countries around the world. The new data were presented at the 64th American Society of Hematology (ASH) Annual Meeting and Exposition taking place in New Orleans from December 10-13, 2022.

The burden of severe hemophilia A in infants and on their parents and caregivers is significant. The World Federation of Hemophilia treatment guidelines consider the standard of care in hemophilia to be regular prophylaxis initiated at a young age, as studies have shown that early prophylaxis improves long-term outcomes, while reducing the risk of intracranial hemorrhage. However, for many infants with hemophilia A, prophylaxis is not started until after the first year of life because of the high treatment burden. Hemlibra provides a flexible treatment option that can be administered subcutaneously from birth at different dosing frequencies.

HAVEN 7 is a Phase III, multi-center, open-label study evaluating the efficacy, safety, pharmacokinetics and pharmacodynamics of Hemlibra in infants with severe hemophilia A without factor VIII inhibitors. The results of this interim analysis, which included data from 54 participants, showed that 77.8% of participants (n=42) did not have any bleeds which required treatment, while 42.6% (n=23) did not have any treated or untreated bleeds at all. There were no treated spontaneous bleeds in any participants, and all treated bleeds were traumatic. A total of 77 bleeds occurred in 31 participants (57.4%); 88.3% were traumatic. Mean model-based annualized bleeding rate (ABR) at the time of interim analysis was 0.4 (95% CI: 0.23–0.65) for treated bleeds.

Hemlibra’s safety profile was consistent with previous studies, with no new safety signals observed. Nine people (16.7%) reported a Hemlibra-related adverse event (AE), all of which were local injection site reactions. Eight participants (14.8%) reported 12 serious AEs, unrelated to Hemlibra. There were no deaths, thromboembolic events or cases of thrombotic microangiopathy, reinforcing Hemlibra’s favorable safety profile. No intracranial hemorrhages occurred.

Primary analysis will be conducted at 52 weeks. The study also has an additional seven-year follow-up period to collect long-term data such as safety and joint health outcomes, further building upon our understanding of the benefit of Hemlibra in this population.

EUHASS Database and ATHN 7 Study: Genentech also presented data from the European Haemophilia Safety Surveillance (EUHASS) database and the prospective observational ATHN 7 study at ASH 2022. Data from EUHASS, which collects real-world safety data on treatments for inherited disorders, showed the safety profile of Hemlibra in people with hemophilia A was favorable and consistent with clinical trial data. Data from ATHN 7, exploring the efficacy of Hemlibra in women with hemophilia A, showed two of the three female participants had no bleeds; the third had one treated bleed associated with a dental procedure and one untreated bleed associated with menses. Ongoing evaluation is vital to further understand the safety and efficacy profile of Hemlibra in this rare and under-represented population.

Hemlibra is approved as a treatment for people with hemophilia A with factor VIII inhibitors in more than 110 countries worldwide, and for people without factor VIII inhibitors in more than 100 countries worldwide. It has been studied in one of the largest clinical trial programs in people with hemophilia A with and without factor VIII inhibitors, including eight Phase III studies.