OBJECTIVES: The objective of this study was to conduct a systematic literature review (SLR) and meta-analysis on the impact of long-acting therapeutics on medication adherence, specifically to compare adherence to different schedules and between long-acting injectables and oral long-acting treatments.

METHODS: Systematic searches were conducted in the MEDLINE and Embase literature databases to identify English-language articles published between January 2002 and May 2020 that compared adherence and persistence outcomes between dosing schedules in patients receiving osteoporosis treatment. The SLR was conducted following PRISMA guidelines, and dual-independent screening was used. Data were captured from each included study by a single reviewer with validation by a second reviewer. Following assessment of the comparability of study designs, outcome definitions, and timepoints, an indirect treatment comparison (ITC) using 12-month data was deemed feasible comparing intravenous every 3 months (quarterly) and subcutaneous every 6 months (biannual) dosing schedules via a link to weekly oral treatment. The analytic approach involved Bucher ITC on the proportion of patients achieving adherence and persistence, expressed as odds ratios (OR).

RESULTS: The SLR identified 12 randomized controlled trials (RCT) and 26 observational studies with comparative data for the outcomes of interest. Of these, three publications on two RCTs had sufficient data to contribute to an analysis network comparing 12 month adherence and persistence outcomes. Both the quarterly and biannual schedules had statistically significant better adherence and persistence results versus the weekly oral treatment. ITC results found no notable differences in performance between quarterly and biannual schedules; with an OR of 1.24 (95% confidence interval [CI] 0.56, 2.76) for adherence and 0.77 (95% CI 0.32, 1.83) for persistence. Analysis of results from observational studies had similar findings.

CONCLUSIONS: The evidence suggests that the longer duration schedules have advantages for adherence and persistence compared with weekly oral treatment in patients receiving osteoporosis therapy.