Adherence, bleeding outcomes and safety profile of Emicizumab Prophylaxis among Haemophilia a patients attending Muhimbili National Hospital, Dar es-salaam, Tanzania.

Abstract

ABSTRACT Background: Prophylaxis is the global standard of care for people with Haemophilia (PWH). Despite being recommended, only a handful of countries in Sub-Saharan Africa have embraced prophylaxis due to limited access to factor concentrates and an excessive dependence on donor assistance. Tanzania initiated the first prophylaxis program, supported by the World Federation of Haemophilia (WFH) by donating Emicizumab to a select group of patients with Haemophilia A. Emicizumab is a monoclonal antibody that restores haemostasis by cross-linking FIXa and X, resulting in thrombin production. Although this agent has been available for the past three years, no studies had examined adherence patterns, bleeding outcomes, and its safety profile in Tanzania. Aim of the study: To evaluate adherence patterns, bleeding outcomes, and the safety profile of Emicizumab prophylaxis among HA patients attending MNH. Methodology: We undertook a cross-sectional analysis involving HA patients receiving Emicizumab prophylaxis, gathering information on their adherence patterns, self-reported adverse events, and bleeding results, which included an annual bleeding rate (ABR) and the resolution of target joints. Factors linked to breakthrough bleeding were assessed using a comprehensive poison method. Results: Among the 55 individuals who participated in the study, the median age was 8 years, and half of the patients (50%) had severe haemophilia. The median ABR for spontaneous bleeding was 8 prior to treatment and decreased to zero after 12 months of prophylaxis. During the study period, a majority of the patients (78%) exhibited adherence. Bleeding was noted in 63% of the patients, predominantly (61%) due to trauma. Of the 19 (34.6%) patients with target joints, 79% saw resolution during Emicizumab prophylaxis. Age was the sole factor linked to breakthrough bleeding, with those over 18 years being the most at risk. Regarding safety, only 5% of the patients reported adverse events, with injection site reactions being the most frequent. Conclusions: The majority of patients adhered to Emicizumab prophylaxis. Emicizumab prophylaxis proves effective in averting spontaneous bleeding and exhibits a favorable safety profile. Older age was the only significant factor associated with spontaneous bleeding during prophylaxis. Ongoing monitoring and pharmacovigilance are crucial for evaluating long-term outcomes and enhancing patient management strategies.