Abstract
Background: Digital communication, including digital refill reminders, is an innovative channel for pharmacy providers to communicate with patients about their medications and improve adherence and persistence on their prescribed medications.
Objectives: The objective of this study was to compare length of HIV pre-exposure prophylaxis (PrEP) utilization and adherence among those who received digital refill reminders to those who did not over a one-year period.
Methods: This retrospective, observational cohort study used administrative claims data from Walgreens, a large, U.S. pharmacy chain. The study sample included PrEP recipients aged 18+ with at least 90 days of PrEP supply in 2016; each patient was followed for up to 12-months from their first fill in the study period. The intervention group was matched 1:1 to the control group based on the following baseline characteristics: age group, gender, payer, copay, new to therapy, and use of a specialized pharmacy. Logistic regression was used to estimate the difference in persistence and adherence between the intervention and control groups. The independent variable, digital refill reminder, was measured as users who received any digital refill reminders in 2016. The dependent variables were persistence and adherence. Persistence was defined as having 9 months of PrEP medication coverage (yes or no) over a 12-month period. Adherence was measured as the modified proportion of days covered (mPDC), which is defined as total days with medication divided by total length of medication use (last fill – first fill).
Results: Propensity score matching resulted in 11,363 PrEP users in each group. After adjusting for covariates, PrEP recipients who received digital refill reminders were 1.8 times more likely to persist on therapy for at least 9 months than those did not (95% CI [1.7, 1.9]; p < .001). Furthermore, PrEP recipients who received digital refill reminders were 1.3 times more likely to achieve an mPDC of at least .90 (95% CI [1.2, 1.4]; p < .001).
Conclusions: The results showed that PrEP users who received digital refill reminders compared to those who did not were more likely to achieve 90% adherence and persist on therapy one year post-index. Limitations of the study include its observational design and a reliance on administrative data from one pharmacy chain. Digital refill reminder tools may help extend length of therapy and improve adherence for HIV PrEP users.
Presenter:
Poster abstracts from the Annual Meeting and Educational Conference for NASP (the National Association of Specialty Pharmacy), September 24–26, 2018, Washington, DC.