Abstract
INTRODUCTION: Continuous treatment with rifaximin 550 mg (hereafter rifaximin) is associated with lower hospitalization rates in patients with hepatic encephalopathy (HE); however, access barriers may exist. This study assessed gaps in rifaximin access and the impact of treatment gaps, particularly those resulting from claim rejections, on hospitalizations and healthcare costs among patients with HE in the United States. METHODS: The IQVIA PharMetrics(®) Plus database linked with Longitudinal Access and Adjudicated Data (2015-2022) were used to identify adults with HE who had ≥ 1 paid rifaximin prescription fill. Rifaximin treatment gaps were assessed during the 12-month period from the first observed attempt at receiving rifaximin (index date). Adjusted number of overt HE (OHE) hospitalizations and healthcare costs were compared over the 6 months following the index date between Cohort 1, who had no gap due to claim rejection and had < 7 days of treatment gap due to other reasons, and Cohort 2, who had ≥ 1 rejection gap or had ≥ 7 days of non-rejection gap. RESULTS: During the year following the index date, 94.7% of the 1711 patients experienced a treatment gap, including 34.8% with initiation gaps from first attempt at receiving rifaximin to first paid claim (77.7% of initiation gaps due to rejected claims) and 72.0% with gaps in access during active treatment (14.8% of active treatment gaps due to rejected claims). Compared with Cohort 1 (n = 432; mean age 56.3 years), Cohort 2 (n = 679; mean age 54.8 years) had 1.55 times the incidence rate of OHE hospitalizations [adjusted incidence rate ratio: 1.55 (95% confidence interval: 1.10-2.20)] and incurred US$1579 more in healthcare-associated costs per-patient-per-month (all p < 0.05). CONCLUSION: Prescription claim rejections frequently led to delays in rifaximin initiation and gaps in access during active treatment. Access barriers to rifaximin were associated with increased hospitalizations and healthcare costs in patients with HE.