Introduction: Objective assessment of treatment effectiveness using real-world claims data is challenging. This study assessed treatment-free intervals (TFI) as a proxy for treatment effectiveness, and all-cause healthcare costs among adult patients with irritable bowel syndrome with diarrhea (IBS-D) treated with rifaximin or eluxadoline in the USA.
Methods: Adult patients (18-64 years) with IBS-D and ≥ 1 rifaximin or eluxadoline prescription were identified in the IQVIA PharMetrics Plus database (10/01/2015-12/31/2021) and classified into two mutually exclusive cohorts (i.