PB0625 - Emicizumab Prophylaxis in People with Hemophilia A Aged ≥50 Years with Comorbidities: Experience From the ATHN 7 Hemophilia Natural History Study

Background: ATHN 7 (NCT03619863) collects real-world data describing long-term safety and effectiveness of therapies for the prevention/treatment of bleeding in people with hemophilia A (PwHA) and other bleeding disorders in the US.

Aims: This analysis examines the characteristics and real-world safety of emicizumab prophylaxis in PwHA aged ≥50 years with comorbidities from ATHN 7.

Methods: ATHN 7 is a longitudinal, observational cohort study; ethics approval and informed consent were obtained. PwHA aged ≥50 years receiving emicizumab were eligible for this analysis, which was supported by Genentech, Inc. Participants were considered to have a comorbidity if they had cardiovascular (CV) risk factors (history of CV disease or current hypertension, diabetes, hyperlipidemia, or obesity), or hepatitis C virus (HCV) and/or human immunodeficiency virus (HIV) infection. Clinical information was collected at baseline and quarterly through participant interview and medical record review. Adverse events (AEs) were documented.

Results: As of 30-Apr-2022, 15 PwHA aged ≥50 years and treated with emicizumab were enrolled in ATHN 7, representing 22.4 patient-years of exposure to emicizumab. Eleven (73.3%) participants had severe HA and 4 (26.7%) had moderate HA; 5 (33.3%) participants had FVIII inhibitors (Table). Ten (66.7%) participants had ≥1 CV risk factor(s) and 6 (40%) had ≥2 CV risk factors. Five (33.3%) participants had HCV infection alone and 9 (60.0%) had HIV/HCV co-infection. Median emicizumab exposure was 84.4 weeks. Three participants reported a total of four AEs: a malignancy in one participant, a subdural hematoma in one participant, and one case of hemorrhagic shock secondary to a presumed gastrointestinal bleed, which resulted in death (previously reported). None were considered emicizumab-related.

Conclusion(s): No thromboses or emicizumab-related AEs were recorded in PwHA aged ≥50 years with pre-existing comorbidities. Continuous data collection is ongoing in the ATHN Transcends study to further evaluate the effectiveness and safety of emicizumab prophylaxis in PwHA.