A Prospective, Noninterventional Study to Evaluate the Impact of Emicizumab in the Management of Hemophilia A

Abstract

Background and objective Hemophilia A (HA) is a genetic bleeding disorder caused by a lack of factor VIII (FVIII) and is associated with frequent bleeding and joint damage. Traditional intravenous treatments for this condition are cumbersome and can lead to complications. Emicizumab, a bispecific monoclonal antibody, offers a promising subcutaneous alternative with potential safety and efficacy-related benefits. This study aimed to evaluate the impact of emicizumab prophylaxis on bleeding rates, joint health, functional activity, and quality of life (QoL) in patients with congenital HA. Methods A noninterventional, prospective observational study was conducted at the Assam Medical College, a tertiary care center in northeastern India, involving 40 patients with HA (PwHA), who were either on FVIII therapy or newly on emicizumab. Emicizumab was given subcutaneously at 3 mg/kg weekly for the first month, followed by 6 mg/kg every four weeks. Endpoints included changes in annual bleeding rate (ABR), Hemophilia Joint Health Score (HJHS), Functional Independence Score in Hemophilia (FISH), and QoL via European Quality of Life 5-Dimensions 5-Levels (EQ-5D-5L) and visual analog scale (VAS) scores at 24 weeks. Results At 24 weeks, HJHS improved from 12.8 to 4.8 (p<0.001), FISH from 27.5 to 30.6 (p<0.001), and ABR decreased from 11.36 to 0.195. Quality of life scores also improved (EQ-5D-5L index from 0.79 to 0.96, VAS from 72.18 to 92.75, both p<0.001). All 30 patients with target joints had resolved bleeds, and adherence to emicizumab was 100%. Conclusions Based on our findings, emicizumab significantly reduces bleeding, enhances joint health, and improves the quality of life in PwHA. It is associated with high adherence, suggesting its feasibility as a treatment, especially in resource-limited settings. However, long-term studies are needed to validate these results.

Keywords: bleeding rate; coagulation factor viii; emicizumab; functional independence; hemophilia a; quality of life; visual analog score.

Figure 1. Schematic flow diagram illustrating the study methodology

ABR: annual bleeding rate; AE: adverse event; EQ-5D-5L: European Quality of Life 5‐Dimensions 5‐levels; EQ-VAS: European Quality Visual Analog Scale; FISH: Functional Independence Score in Hemophilia; HJHS: Hemophilia Joint Health Score; PwHA: people with hemophilia A Image credit: Anupam Dutta

Figure 2. Individual comparison of HJHS at baseline and after 24 weeks

HJHS: Hemophilia Joint Health Score

Figure 3. Individual comparison of FISH at baseline and after 24 weeks

FISH: Functional Independence Score in Hemophilia

Figure 4. Comparative analyses of ABR and mean no. of target joints at baseline and after 24 weeks

ABR: annual bleeding rate

Figure 5. Incidence of bleeding episodes in patients after emicizumab prophylaxis

Figure 6. Comparison of individual EQ-5D-5L score index (A) and VAS score (B) between baseline and the first visit after emicizumab therapy

EQ-5D-5L: European Quality of Life 5-Dimensions 5-Levels; VAS: visual analog scale

Figure 7. HJHS questionnaire

https://www.hemophilink.fr/wp-content/uploads/2019/01/Hemophilia-joint-health-score-HJHS.pdf HJHS: Hemophilia Joint Health Score

Figure 8. FISH questionnaire

https://elearning.wfh.org/resource/functional-independence-score-in-hemophilia-fish/ FISH: Functional Independence Score in Hemophilia

Figure 9. EQ VAS score questionnaire

https://www.sciencedirect.com/science/article/pii/S1279770723010667 EQ-VAS: European Quality Visual Analog Scale