PB0239 - Malaysia: Long-term real-world experience in clinical outcomes of reduced dose emicizumab in Haemophilila A with inhibitors

Background: Emicizumab is an efficacious prophylaxis for patients with Haemophilia A especially inhibitors; however the cost of remains high. We report our 5-year experience with emicizumab and at reduced dose which is effective and potentially more affordable.

Aims: Demonstrate low dose emicizumab as a cost-effective alternative for poor resource countries

Methods: Retrospective review of patients on emicizumab from June 2018 till Dec 2023 and their journey through dose reduction. The outcomes assessed were breakthrough bleeding, min dose tolerated per subject and adverse events.

Results: Ten Haemophilia A patients with inhibitors received emicizumab; maximum treatment duration of 267 weeks. Eight patients received standard recommended dose of emicizumab with subsequent dose reduction whilst two of them received low dose emicizumab; without loading dose, from the outset. Prior to emicizumab, they received on demand bypassing agents with an annualised bleeding rate of 3 to 92. After emicizumab there was reduction in bleeding events ie 1 bleeding episode which was treated conservatively. Dose reduction was done gradually as shown in table 1; with a lowest dose of 1.5mg/kg every 4 weeks. Patients received single vial dose and per-body weight dose change was due to increase in weight or dosing intervals. At lower dose, 4 patients experienced bleeding; 3 of which were provoked. One had persistent ankle pain and treatment was stopped. One suffered myocardial infarction with failed conservative medical therapy and succumbed to heart failure. Both patients who received low dose emicizumab without loading dose showed no bleeding during treatment. However treatment had to be stopped due to cost; one was recruited into a clinical trial whilist the other had returned to on demand therapy.

Conclusion(s): Even at reduced dose, emicizumab continues to demonstrate favourable efficacy and bleeding outcomes. This provides a cost effective alternative for prophylaxis in Haemophilia A with inhibitors especially from resource limited countries.