Objectives:
The longer-term clinical outcomes of patients using emicizumab in real world settings are not well documented. This study examined hemophilia patient clinical outcomes, specifically bleed rate, emergency room visits/hospitalizations, nurse resource use, adherence and emicizumab wastage in the 6 months before and after initiating emicizumab.
Methods:
This is a retrospective cohort study of patients in the United States who received an emicizumab prescription between July 1, 2018 and July 1, 2019 from a single specialty pharmacy. Patients with moderate (1% to 5% factor activity) to severe (<1% factor activity) hemophilia were included if they took emicizumab for at least 6 months and had 6 months prior use of a prophylactic factor product. Self-reported bleeds, emergency room visits, hospital admissions and nurse visits (a visit by a nurse to provide administration, education and/or infusion of the drug) were obtained from the patient’s electronic medical record. Medication adherence was assessed by calculating proportion of days covered (PDC) (the number of days in period treated divided by number of days in period) using medication dispense date and quantity from the pharmacy dispensing system. Paired Wilcoxon signed-rank and McNemar’s tests were used to assess changes in outcomes. A one-way ANOVA was used to compare emicizumab waste (the amount of drug (mg) not used per month, across the 6 months after initiating emicizumab).
Summary:
The median participant age was 15 years (range 3-53) (N=35); all were male. After initiating emicizumab, patients reported 55% fewer bleeds (m=2.9 vs. 1.3; p=0.001), 83% fewer nurse visits (m=15.5 vs. 2.8; p=0.01) and 15% greater medication adherence (m=0.84 vs. 0.97; p=0.04). When stratifying by age, the reduction in nurse visits was only significant among patients under age 18 (p = 0.01) and the increase in medication adherence was only significant among adults 18+ (p=0.01). There was no difference in emergency room/hospital visits after initiating emicizumab (m=0.40 vs. 0.23; p = 0.4). Most patients (51.4%) reported emicizumab wastage in the first month. After the initial loading dose (month 1), there was a decreasing proportion of emicizumab waste across months 2-6, though comparisons were not statistically significant (13.8%, 13.3%, 12.1%. 12.4% and 10.9%; p>0.6). Although the intent was not to assess cost savings, our study did find a 9.1% savings in drug cost over the course of one year, when comparing factor utilization pre-emicizumab.
Conclusions:
In this study, taking emicizumab was associated with a significant reduction in bleeds and nursing visits which may reduce operational costs and increase medication adherence. No significant change in emergency room/hospital visits were observed. Future prospective studies with larger samples and a control group are needed to assess long-term clinical outcomes, health-related quality of life, and total cost and quality of care among patients using emicizumab.