412 - Medication Possession Ratio (MPR) and Satisfaction with Oral L-Glutamine (Gln) in Children with Sickle Cell Disease (SCD) with Specialty Pharmacy Services
Resident Physician University of Illinois at Chicago University of Illinois at Chicago College of Medicine Chicago, Illinois, United States
Background: MPR is a central measurement for medication adherence, with a benchmark ratio of 80% for good compliance. Glutamine (Gln) was FDA-approved in 2017 to reduce acute SCD pain and acute chest syndrome. When there are no interventions to enhance adherence, moderate adherence (MPR<80%) is typical among pediatric patients for medications prescribed for SCD: hydroxyurea (60%), folic acid (61%), and penicillin (55%). At the University of Illinois (UI Health), an integrated specialty pharmacy navigates the insurance authorization process and completes monthly patient assessments.
Objective: To compare adherence, number of prescription fills, rate of prior-authorization approval, and patient satisfaction with Gln between pediatric and adult patients in a large academic center with specialty pharmacy services.
Design/Methods: Patients were selected using the following criteria: managed by UI hematologist, new to therapy, and received dispensed medication via UI Specialty Pharmacy from 2018 to 2020. Cases with 1 fill were excluded. A Wilcoxon Rank Sum test (α= 0.05) was performed to evaluate differences in adherence and number of prescription fills. A χ2 test (α=0.05) was used to assess differences in patients’ first fill approval rate and satisfaction with therapy.
Results: 55 cases met selection criteria (n=25, age<18y; n=30, adults), excluding cases with 1 fill (n=6, age<18y; n=9, adults). Children exhibited no significant difference in MPR compared to adults [72% vs. 76%; p=0.587]. Compared to adults, children demonstrated a significantly higher number of fills [9.11 vs. 3.86; p= 0.007] and significantly lower first attempt approval rate [74% vs. 95%; p= 0.0026]. Pediatric and adult satisfaction with Gln therapy showed no significant difference in ratings of 'excellent' [89% vs. 90%; p=0.82]. Conclusion(s): Gln had a higher MPR compared to historical data for other medications prescribed for SCD. There was no significant difference in adherence and satisfaction with Gln therapy between pediatric and adult patients. Pediatric patients had a significantly lower first attempt insurance approval rate, suggesting an initial barrier to access. However, children demonstrated a statistically higher number of fills with Gln compared to adults, which suggests that an interdisciplinary collaboration among physicians, specialty pharmacists, and parents may facilitate sustainable management of a new therapy. Tracking medication adherence metrics could help optimize care in SCD.
Authors/Institutions: Han-Wei Wu, University of Illinois at Chicago College of Medicine, Chicago, Illinois, United States; Khoa Le, University of Illinois at Chicago, Chicago, Illinois, United States; Michael Gannon, University of Illinois at Chicago, Chicago, Illinois, United States; Lewis Hsu, University of Illinois at Chicago College of Medicine, Chicago, Illinois, United States