OBJECTIVES: To review and outline the status of current Real-World Evidence (RWE) demonstrating adherence advantages and effectiveness of LAIs in schizophrenia treatment.

METHODS: A comprehensive review of literature (2010-present) was undertaken by two reviewers with articles retrieved from Embase, PubMed/Medline, EBSCO, ScienceDirect, PsycINFO, and Cochrane Library databases, employing appropriate adherence and utilization-specific search terms for LAI use in schizophrenia. Selected articles were classified according to the type of data sourced (primary, secondary, patient-reported, observational, etc.), research design employed to generate RWD (RCT, cohort & case-control, mirror-image studies, and others), and effectiveness outcomes that were targeted (primary adherence outcome and other).

RESULTS: 37 studies (both domestic and international) met the study inclusion criteria and the data needed to address the research objectives. Majority of the studies (n=26) involved a direct comparison with oral antipsychotics (OAPs) in which LAIs exhibited a clear superiority with respect to the primary outcome of adherence (n=19). Utilization-related outcomes in which LAIs showed improvement included, among other factors, time to discontinuation, relapse, rehospitalization, LOS, functional status, and cognitive functioning. Proportion of Days Covered (PDC), time until initial nonadherence, discontinuation rates, and Medication Gap were the most frequently used adherence tools. The reported improvement in medication adherence with LAI use across multiple studies varied with respect to the population studied, care setting, data type, and study design (a range of 30.90%-82.0%). Only two studies reported evidence to the contrary.

CONCLUSIONS: More RWD from RCTs and observational studies are needed than is reported in the literature. Although not conclusive or adequate, evidence mostly supports LAI’s positive impact on adherence in maintenance treatment, health outcomes, and hospitalization. Some evidence documenting the effectiveness of early-use LAIs is beginning to emerge, but uncertainties remain regarding the effectiveness of newer LAIs over first-generation LAIs.