BACKGROUND: Irritable bowel syndrome with diarrhea (IBS-D) is a chronic disorder of gut-brain interaction that negatively affects work productivity and health-related quality of life (HRQOL). IBS-D therapeutic options are limited and include loperamide, an over-the-counter μ-opioid receptor agonist commonly used as an antidiarrheal agent, and eluxadoline, a mixed μ- and κ-opioid receptor agonist and δ-opioid receptor antagonist approved in the United States for the treatment of IBS-D in adults. OBJECTIVE: To characterize the effect of eluxadoline on work productivity and HRQOL in patients with IBS-D with previous inadequate response to loperamide. METHODS: The Work Productivity and Activity Impairment Questionnaire for IBS-D (WPAI:IBS-D), Centers for Disease Control and Prevention Healthy Days Core Module (CDC HRQOL-4), and EuroQoL-5 Dimension (EQ-5D) instruments were administered at baseline and week 12 of a phase 4 clinical trial (RELIEF), assessing the efficacy and safety of eluxadoline treatment in adults with IBS-D reporting previous inadequate response to loperamide. Changes from baseline to week 12 for each assessment were evaluated using an analysis of covariance model. Indirect costs were calculated by converting overall work productivity losses into monetary values. RESULTS: A total of 346 patients were randomized to either eluxadoline (n = 172) or placebo (n = 174). From baseline to week 12, compared with placebo, twice-daily treatment with eluxadoline resulted in significantly greater reductions in absenteeism (2.6%; P = 0.046). Numerically greater decreases in presenteeism, overall work productivity loss, and daily activity impairment were also observed in patients receiving eluxadoline compared with those receiving placebo (P = not significant for each). Numerical reductions in overall work productivity loss from baseline to week 12 translate to approximately 2.4 hours per patient per week (123 hours annually) and correspond to an avoided overall work loss of $4,503 annually for an employee with IBS-D treated with eluxadoline. In addition, from baseline to week 12, treatment with eluxadoline led to a significantly greater reduction in the number of unhealthy days experienced (-1.7 days; P = 0.042), as well as numerical improvements in EQ-5D measures in comparison with placebo (P = not significant for each). CONCLUSIONS: In patients with IBS-D reporting inadequate response to loperamide, eluxadoline treatment was associated with significant reductions in absenteeism and the number of unhealthy days experienced. Eluxadoline treatment of IBS-D may lead to significant cost savings via mitigation of losses in work productivity. DISCLOSURES: This study was sponsored by Allergan plc (before acquisition by AbbVie, Inc.). Allergan plc and/or AbbVie, Inc., was involved in the study design, collection, analysis, interpretation of the data, writing of the report, and the decision to submit the report for publication. Abel and Burslem are employees of AbbVie, Inc., and own stock/stock options. Brenner has served as a consultant, speaker, and/or advisor for Allergan plc (before acquisition by AbbVie, Inc.), Alnylam, Alpha Sigma, Arena, Bayer, Ironwood Pharmaceuticals, Salix Pharmaceuticals, Shire, Synergy, and Takeda Pharmaceuticals. He is also supported in research by an unrestricted gift from the Irene D. Pritzker Foundation. Sayuk has served as a consultant and speaker for Allergan plc (before acquisition by AbbVie, Inc.), Gi Health Foundation, Ironwood Pharmaceuticals, Salix Pharmaceuticals, and Synergy. Portions of the current work were presented at AMCP Nexus; October 22-25, 2018; Orlando, FL.