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Tail Vein Transection Bleeding Model in Fully Anesthetized Hemophilia A Mice
Published on: September 30, 2021
Real-world adherence to and persistence with emicizumab in people with hemophilia A using a national claims database
Janet S Lee1, Robert Schuldt1, Zhiyu Xia1
1Genentech, Inc., South San Francisco, CA.
Background:
Substantial rates of nonadherence are observed among people with hemophilia A (PwHA) receiving standard- or extended-half-life factor (F)VIII replacement products, although better adherence is associated with fewer bleeding events and better quality of life. Emicizumab is the first bispecific FIXa-/FX-directed antibody approved for routine prophylaxis in PwHA. More real-world adherence and persistence data on emicizumab and other new hemophilia treatments are needed to better inform decisions on population health care and individualized treatments for PwHA.
Objective:
To describe real-world emicizumab adherence and persistence among PwHA in the United States.
Methods:
This retrospective, observational cohort study used adjudicated health plan claims data from IQVIA PharMetrics Plus. This study included PwHA with at least 1 claim noting hemophilia A diagnosis between May 1, 2017, and September 30, 2023; at least 2 claims for emicizumab fills between November 1, 2017, and September 30, 2023; and continuous medical and pharmacy insurance benefit coverage for at least 6 months before and at least 12 months after the first emicizumab fill (index date). Adherence to emicizumab was measured during the 12-month post-index period using the proportion of days covered (PDC). Persistence was defined as the proportion of PwHA who did not discontinue emicizumab during the post-index period, where discontinuation was defined as a treatment gap of at least 60 days. Among adherent PwHA (PDC ≥ 80%), the number of post-index claims for FVIII were evaluated.
Results:
A total of 280 PwHA were included in the study, of whom 98% were male and the mean age was 26 (SD = 16) years. Overall, 76% of PwHA were adherent to and 85% of PwHA were persistent with emicizumab. Rates of adherence and persistence were high across age- and geography-based subgroups, ranging from 61% to 97%. Among PwHA adherent to emicizumab (n = 213), 57% had no post-index claims for FVIII.
Conclusions:
In the first year following emicizumab initiation, high adherence and low discontinuation rates were observed among PwHA in a real-world setting.
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