Effect of Pharmacogenetic-Based Decision Support Tools in Improving Depression Outcomes: A Systematic Review

Evidence supporting the utility of pharmacogenetic (PGX) tests in depression is scarce. The main objectives of this study were to summarize, update, and assess the quality of the available evidence regarding PGX testing in depression as well as estimating the impact of using PGX testing tools in depression outcomes in the Middle East/North Africa (MENA) region.

Scientific databases were systematically searched from inception to June 30, 2020 for systematic reviews and randomized controlled trials (RCTs) assessing the clinical utility of PGX tests in the treatment of depression. Meta-analyses only and RCTs that were included in eligible systematic reviews were excluded. The quality of the eligible studies was assessed using the Crowe Critical Appraisal Tool (CCAT).

Six systematic reviews and three RCTs met the inclusion criteria and were included in this study. The results of the systematic reviews provided weak evidence on the efficacy of PGX testing, especially in patients with moderate-severe depression at 8 weeks. In addition, there was a lack of evidence regarding safety outcomes. Newer RCTs with better quality showed clinical promise regarding efficacy outcomes, especially in patients with gene-drug interactions. No evidence was found regarding PGX testing impact in the MENA region.

This systematic review is an update and summary of the available literature on the clinical utility of PGX testing in depression. The findings of this study demonstrate that PGX testing prior to treatment initiation or during the course of therapy may improve efficacy outcomes. Further studies are warranted to assess the impact of PGX testing on safety outcomes.