Patients with severe hemophilia A often have to give up even light physical activities due to joint pain, let alone exercise.

However, a recent study has shown that these patients drastically improved their quality of life by reducing the frequency of bleeding and could engage in physical activities one year after receiving Hemlibra (emicizumab).

Hemlibra, introduced by JW Pharmaceutical, is a genetically recombinant drug developed by Japan's Chugai Pharmaceutical. It is a new drug that supplements blood clotting factors for hemophilia A patients who have produced antibodies caused by a deficiency of blood clotting factor 8.

The Cochin Hospital Haemophilia Treatment Center in France investigated the general health and adverse events of 38 patients with severe hemophilia A without antibodies to factor 8 for one year after taking Hemlibra.

The average age of the 38 patients was 45.5±13.21 years, and 37 had hemophilic arthropathy. On average, they had 4.32±1.83 joints with hemophilic arthropathy, and 30 (78.95 percent) were on prophylaxis with existing therapies.

After one year of treatment with Hemlibra in 38 patients with severe hemophilia A, patient self-assessed general health improved to 4.5 out of the full six on Hemlibra from 3.6 on conventional therapy, and the group's general health VAS score as determined by the EQ-5D-3L survey was 69.6 (±19.4) out of 100.

The frequency of spontaneous bleeding, measured by a VAS score of zero (never) to six (very often), improved to 0.41 with Hemlibra compared to 3.05 with conventional treatment. The frequency of post-traumatic bleeding improved significantly (<0.0001) to 0.86 with Hemlibra compared to 3.33 with conventional treatment, demonstrating a reduction in both types of bleeding.

Patients' perceived chronic pain intensity also improved significantly with Hemlibra, from 3.32 pre-treatment to a mean of 0.86 post-treatment.

Regarding physical activity, 15 patients (39.5 percent) resumed activities that they could no longer do, and eight patients (21.1 percent) started new activities, showing a significant improvement in activity after taking Hemlibra.

During the period, 16 adverse events occurred in patients receiving Hemlibra during this period, including 14 injection site reactions (ISRs), none of which led to discontinuation of the drug. There were no deaths or thrombotic microangiopathies.

"These results demonstrate the efficacy and safety of Hemlibra in patients with non-antibody mild to moderate hemophilia A," the researchers said.

The study was published in Haemophilia 2023.