Interim data from phase III HAVEN 6 study demonstrate favorable safety and efficacy profile of Hemlibra in people with moderate or mild hemophilia A.

The data were presented at the 63rd American Society of Hematology (ASH) Annual Meeting and Exposition as an oral presentation on December 12, 2021.

While the treatment and management of severe hemophilia A are well established, there is less information and treatment guidance on moderate and mild hemophilia A, which can lead to delayed or missed diagnoses of bleeding episodes. Considering this population may not use preventative treatments, these patients may experience worsened clinical burden, with less than 30% of people with moderate or mild hemophilia A living a bleed-free life.

HAVEN 6 is a Phase III study evaluating the safety, efficacy, pharmacokinetics and pharmacodynamics of Hemlibra in people with moderate or mild hemophilia A without factor VIII inhibitors. This interim analysis included data from 71 participants (69 men and two women), 20 of whom had mild hemophilia A without factor VIII inhibitors and 51 of whom had moderate hemophilia A without factor VIII inhibitors. Thirty-seven participants were on factor VIII prophylaxis at baseline. This interim analysis was conducted after 50 participants with moderate hemophilia A completed at least 24 weeks in the study or withdrew. Data cutoff was on April 16, 2021.

These data show Hemlibra demonstrated a favorable safety profile and effective bleed control in the HAVEN 6 study, with 80.3% of participants experiencing no bleeding episodes that required treatment and 90.1% experiencing no joint bleeds that required treatment. Annualized bleeding rates (ABR) remained low, consistent with previously reported observations from the HAVEN 1-4 studies. In addition, of the 50 participants aged 12 years or older who responded to the EmiPref questionnaire, 48 (96.0%) preferred Hemlibra to their previous treatment, one preferred their old treatment, and one expressed no preference.

The most common adverse events (AEs) occurring in 10% or more people in the HAVEN 6 study were headache (14.1%) and local injection site reactions (ISRs) (12.7%). Eleven people (15.5%) reported a Hemlibra-related AE, with ISRs being the most common (12.7%). There were no deaths, or cases of thrombotic microangiopathy (TMA) or serious thrombotic events (TEs) in the study as of the data cutoff, reinforcing Hemlibra’s favorable safety profile.

A separate analysis of TE and TMA events in people taking Hemlibra, including real-world data, will also be presented as a poster at ASH . These results showed that the evaluation of reported events without concomitant activated prothrombin complex concentrate (aPCC) remains similar to previous analyses as exposure increases, and the benefit/risk profile of Hemlibra remains unchanged. These data further confirm the favorable safety profile of Hemlibra, consistent with results from previous HAVEN and STASEY studies.

Hemlibra is approved to treat people with hemophilia A with factor VIII inhibitors in more than 100 countries worldwide and people without factor VIII inhibitors in more than 90 countries worldwide, including the U.S., EU and Japan. Hemlibra 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.