New data for Roche’s Hemlibra reinforce safety profile in people with haemophilia A

Roche announced results from the final analysis of the phase IIIb STASEY study, which confirm the favourable safety profile of Hemlibra (emicizumab), consistent with the phase III HAVEN clinical programme. In the analysis, no new safety signals were identified with longer-term Hemlibra treatment in adults and adolescents with haemophilia A with inhibitors to factor VIII, the clotting protein that is missing or defective in people with haemophilia A. The data were presented at the virtual International Society on Thrombosis and Haemostasis (ISTH) 2021 Congress, 17-21 July 2021.

“As the treatment landscape evolves, determining the long-term benefit/risk profile of medicines for people living with haemophilia A remains a top priority for the community,” said Levi Garraway, M.D., Ph.D., Roche’s Chief Medical Officer and Head of Global Product Development. “These results provide further confidence in Hemlibra’s favourable safety profile in people with haemophilia A with factor VIII inhibitors, who have historically faced significant treatment challenges.”

Nearly one in three people with haemophilia A develop factor VIII inhibitors, antibodies that bind to and block the efficacy of replacement factor VIII. People with haemophilia A with inhibitors are at greater risk of more frequent bleeding, including life-threatening bleeds, and may face greater challenges in their day-to-day lives than people with haemophilia A who do not have inhibitors. Hemlibra has been approved in more than 100 countries worldwide for the treatment of people with haemophilia A with factor VIII inhibitors.

The final analysis of the STASEY study included data from 193 people with haemophilia A with factor VIII inhibitors, who received Hemlibra prophylaxis once-weekly for up to two years (median treatment duration of 103.1 weeks). The analysis did not show any new cases of thrombotic microangiopathy or serious thrombotic events (adverse events [AEs] that have been observed in people with bleeding disorders) related to Hemlibra. The most common AEs occurring in 10% or more of people in the STASEY study were joint pain (arthralgia; 17.1%), common cold symptoms (nasopharyngitis; 15.5%), headache (15.0%), injection site reaction (ISR; 11.4%) and fever (pyrexia; 10.9%). Thirty-five (18.1%) people reported a Hemlibra-related AE, with ISRs being the most common (9.8%).

In addition, the STASEY study reinforced that Hemlibra is associated with a low incidence of anti-drug antibody (ADA) development. Ten participants (5.2%) tested positive for ADAs, five (2.6%) of whom were classified as having ADAs that were neutralising in vitro. In all ten participants, ADA development did not affect the efficacy or safety of Hemlibra; none of the participants had ADAs that resulted in a decrease in Hemlibra plasma concentration, and none of the ADA-positive participants experienced a treated bleed. In addition, the ADAs disappeared over time, as all study participants tested negative for ADAs at their last visit.

Hemlibra also continued to demonstrate effective bleed control in the STASEY study, with 82.6% of participants experiencing no bleeding episodes that required treatment. Annualised bleeding rates were consistent with previously reported observations from the pivotal HAVEN studies.

Hemlibra is approved to treat people with haemophilia A with factor VIII inhibitors in more than 100 countries worldwide and people with haemophilia A without factor VIII inhibitors in more than 80 countries worldwide, including the US, EU and Japan. Hemlibra has been studied in one of the largest clinical trial programmes in haemophilia A with and without factor VIII inhibitors, including eight phase III studies.