Treatment-Free Interval: A Novel Approach to Assessing Real-World Treatment Effectiveness and Economic Impact Among Patients with Irritable Bowel Syndrome with Diarrhea.

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.e., rifaximin and eluxadoline). Index date was the date of rifaximin or eluxadoline initiation. Entropy-balanced baseline characteristics, TFI (periods of ≥ 30 consecutive days without IBS-D treatment), and healthcare costs were reported. Healthcare costs were compared between cohorts using mean cost differences. RESULTS: There were 7094 and 2161 patients in the rifaximin and eluxadoline cohorts, respectively. After balancing, baseline characteristics (mean age 44.1 years; female 72.4%) were similar between cohorts. A higher proportion of patients treated with rifaximin achieved a TFI of ≥ 30 days (76.2% vs. 66.7%), ≥ 60 days (67.0% vs. 47.0%), ≥ 90 days (61.0% vs. 38.7%), ≥ 180 days (51.7% vs. 31.0%), and ≥ 240 days (47.7% vs. 27.9%) compared to eluxadoline. Among patients with a TFI ≥ 30 days, mean TFI durations were 8.3 and 6.0 months for the rifaximin and eluxadoline cohorts. Mean all-cause healthcare costs were lower for rifaximin vs. eluxadoline ($18,316 vs. $23,437; p = 0.008), primarily driven by pharmacy costs ($7348 vs. $10,250; p < 0.001). In a simulated health plan of one million commercially insured lives, initiating 50% of patients on rifaximin instead of eluxadoline resulted in total cost savings of $2.1 million per year or $0.18 per-member-per-month. CONCLUSIONS: This real-world study suggests that TFI is a meaningful surrogate measure of treatment effectiveness in IBS-D. Patients treated with rifaximin had longer treatment-free periods and lower healthcare costs than patients treated with eluxadoline.

Impact of rifaximin use following an initial overt hepatic encephalopathy hospitalization on rehospitalization and costs.

AIM: To assess the impact of rifaximin (± lactulose) use following discharge of an initial overt hepatic encephalopathy (OHE) hospitalization on OHE rehospitalizations and healthcare costs in a real-world setting. METHODS: Adults (18-64 years) with an OHE hospitalization were identified from MarketScan® Commercial claims (Q4'15-Q2'20), classified into two mutually exclusive treatment cohorts (i.e. rifaximin and no rifaximin treatment), and further stratified into four subgroups based on decreasing quality of care (QoC; i.e. Type 1 - rifaximin without delay post-discharge; Type 2 - rifaximin with delay post-discharge; Type 3 - lactulose only post-discharge; Type 4 - no rifaximin/lactulose treatment post-discharge). The impact of rifaximin use on 30-day and annualized OHE hospitalizations and healthcare costs were assessed between cohorts and by the QoC subgroup. RESULTS: Characteristics were similar between the rifaximin (N = 1,452; Type 1: 1,138, Type 2: 314) and no rifaximin (N = 560; Type 3:337, Type 4: 223) treatment cohorts. The 30-day risk of OHE rehospitalization was lower for the rifaximin vs. no rifaximin treatment cohort (odds ratio 0.56, p < .01) and increased with decreasing QoC. The annual rate of OHE hospitalizations was 59% lower for the rifaximin treatment cohort (incidence rate ratio 0.41, p < .01) and increased with decreasing QoC. Compared to the no rifaximin treatment cohort, the rifaximin treatment cohort had higher pharmacy costs, lower medical costs, and no difference in total healthcare costs. LIMITATIONS: This was a claims-based study subject to common data limitations such as billing inaccuracies or omissions in coded claims. Total healthcare costs were reported from a payer's perspective, which do not capture indirect costs associated with patient burden. CONCLUSIONS: Initiation of rifaximin after an OHE hospitalization was associated with reduced OHE hospitalizations both in the 30-days following and annually. Further, reduced medical costs offset increased pharmacy costs, and no annual cost differences were observed between cohorts.

High rifaximin out-of-pocket costs are associated with decreased treatment retention among patients with hepatic encephalopathy.

BACKGROUND AND AIMS: Hepatic encephalopathy (HE) is associated with significant morbidity and mortality for those with cirrhosis. Despite the known benefits of rifaximin use for HE, treatment retention remains low. This study aimed to evaluate the impact of out-of-pocket (OOP) rifaximin cost on treatment retention among commercially insured patients in the United States. METHODS: Adult patients with cirrhosis and HE were identified from the IBM MarketScan claims database. Those who began rifaximin treatment between January 1, 2011, and December 1, 2021 were included. Regression models were used to analyze the relationship between patients' 30-day OOP rifaximin cost and rifaximin retention (≥80% eligible days with rifaximin supply) at 180, 360, and 540 days. Models were controlled for patient demographic and clinical characteristics including age, sex, comorbid conditions, Charlson comorbidity index (CCI), and lactulose use. RESULTS: A total of 6839 adult patients were included. Most patients were between 55 and 64 years (57.1%), male (60.4%), and living in urban settings (84.6%). Treatment retention was low for all time periods; retention rates for rifaximin were 42%, 25%, and 16% at 180, 360, and 540 days, respectively. In multivariable analysis, 30-day OOP costs of ≥ $150 were associated with a decreased likelihood of rifaximin retention at 180, 360, and 540 days [relative risk (RR) = 0.67, RR = 0.62, and R = 0.60, respectively]. Younger age was associated with reduced treatment retention for all time periods. Metastatic cancer and depression were associated with reduced treatment retention at 180 days (RR = 0.70 and RR = 0.87, respectively). CONCLUSIONS: Rates of rifaximin treatment retention are low despite the known benefits of rifaximin use for breakthrough HE. High 30-day OOP cost is associated with reduced rifaximin treatment retention.

Assessment of small intestinal bacterial overgrowth and methane production in patients on chronic proton-pump inhibitor treatment: prevalence and role of rifaximin in its management in primary care.

BACKGROUND: Although proton pump inhibitor (PPI) drugs have considered able to induce small intestinal bacterial overgrowth (SIBO), no data are so far available from primary care (PC). We assessed the prevalence of SIBO and methane (CH4) production consequent to chronic PPI therapy using Lactulose Breath Test (LBT). Secondary aim was to explore the possible role of rifaximin in treating PPI-induced SIBO patients. METHODS: One hundred twenty-five gastroesophageal reflux disease patients, constantly treated with PPI for at least 6 months and undergoing to LBT, were retrospectively assessed. An age-matched control population (control) of 100 patients, which had not used PPI in the last 6 months, was also enrolled. In the PPI group, SIBO positive patients and CH4 producers were treated with rifaximin 1200 mg/daily for 14 days and re-checked with LBT one month after the end of treatment. The area under the curve (AUC) before and after treatment was also calculated for both SIBO positive patients and CH4 producers. RESULTS: In the PPI group, SIBO prevalence was significantly higher vs. controls (38/125 [30.4%] vs. 27/100 [27%], P<0.05). 77/125 (61.6%) PPI patients were found to be CH4 producers vs. 21/100 (21%) controls (P<0.05). Among SIBO patients in the PPI group, 34 (89.4%) were also CH4 producers vs. 17/27 (63%) controls (P<0.05). After treatment, LBT resulted negative in 15/22 SIBO patients (68.1%) (P<0.05) and in 18/34 CH4 producers (52.9%) (P<0.05). At the AUC analysis, an overall reduction of 54.2% for H2 in SIBO patients and of 47.7% for CH4 was assessed after rifaximin treatment (P<0.05). CONCLUSIONS: Our data showed that chronic use of PPI could be able to increase the prevalence of SIBO and to shift the intestinal microbial composition towards a CH4-producing flora. rifaximin could represent a useful therapeutical option for PPI-induced SIBO and for modulating CH4-producing flora.

Racial and ethnic disparities in rifaximin use and subspecialty referrals for patients with hepatic encephalopathy in the United States.

BACKGROUND & AIMS: Rifaximin use in combination with lactulose is associated with a decreased risk of overt hepatic encephalopathy (HE). We sought to determine whether race and ethnicity were associated with rifaximin prescriptions. METHODS: We examined data for a 20% random sample of United States Medicare enrollees with cirrhosis and hepatic encephalopathy treated with outpatient lactulose and Part D prescription coverage from 2011-2019. Beginning at the time of first diagnosis, we evaluated time to first prescription of rifaximin accounting for competing risks (Fine-Gray, yielding subdistribution hazard ratios [sHRs]) and cumulative rifaximin exposure using a gamma hurdle model (yielding exposure length ratios). We aimed to determine the association of race and ethnicity with each outcome, adjusting for demographics, clinical factors, and other features of clinical management. RESULTS: Overall, 29,095 patients were diagnosed with HE and treated with lactulose, of whom 13,272 were prescribed rifaximin. Compared to White patients, Black patients were least likely to receive any prescription for rifaximin (sHR 0.70; 95% CI 0.65-0.76). Asian and Hispanic patients were also less likely to receive rifaximin compared to White patients. Black patients also received fewer doses of rifaximin (exposure length ratio 0.90; 95% CI 0.82-0.98). Hispanic patients also received fewer doses (0.88; 95% CI 0.80-0.98). Out-of-pocket spending on rifaximin per person-year was higher for Black and Hispanic than White patients. Out-of-pocket medication spending was associated with reduced odds of filling a rifaximin prescription. Black and Hispanic patients were least likely to be referred to a gastroenterologist. CONCLUSION: In a national cohort of patients with HE, we observed stark racial and ethnic disparities in the use of rifaximin, an approved therapy for the improvement of HE-specific outcomes. Access to gastroenterologists and cost controls may reduce disparities. LAY SUMMARY: Hepatic encephalopathy is a serious problem that can affect people with cirrhosis. When someone develops hepatic encephalopathy, there are 2 main treatments. The first-line treatment is called lactulose. If episodes of hepatic encephalopathy happen on lactulose, another treatment called rifaximin is recommended. In this study, we found that compared to White patients, Black and Hispanic patients are less likely to be prescribed rifaximin, receive fewer rifaximin refills, spend more on rifaximin, and have less access to subspecialists who are familiar with rifaximin. We conclude that efforts to address the cost of rifaximin and access to gastroenterologists could help improve these disparities.

Incidence of, Risk Factors for, and Outcomes After Ascites in a Population-Based Cohort of Older Americans.

BACKGROUND: The incidence of, risk factors for, and outcomes after the development of ascites are poorly described for contemporary patients with cirrhosis. METHODS: We examined data for a 20% random sample of US Medicare enrollees with cirrhosis and Part D prescription coverage from 2008 to 2019, excluding patients with heart failure and diuretic use prior to cirrhosis. Among 63,364 persons with cirrhosis, we evaluated the incidence of ascites using an Aalen-Johansen estimator. We evaluated risk factors for ascites, mortality, and mortality after ascites using multistate modeling. We determined the associations with each outcome for an array of medication exposures including nonselective beta-blockers, antiviral therapy, statins, rifaximin, anticoagulants, and metformin. RESULTS: The cumulative incidence of ascites was 5.1%, 9.5%, and 10.7% and 1, 3, and 5 years overall. The corresponding data for ascites requiring paracentesis were 1%, 2.1%, and 2.4%. Persons aged < 65 years, with alcohol-related cirrhosis, varices, or HE, are most likely to develop ascites. The risk of ascites was higher for persons taking any NSBB (including carvedilol) but lower for those taking atorvastatin (but not other statins) and antiviral therapy for Hepatitis C. Incident ascites was associated with increased risk of death, HR 27.6 95%CI(21.7-35.1). Survival following ascites was 1.08 years (interquartile range, IQR, 0.26-2.75), 0.38 years (IQR0.1-1.3) for those requiring paracentesis. Lipophilic statins were the only medications associated with lower mortality after ascites requiring paracentesis. CONCLUSIONS: Ascites is associated with a high risk of death. Very few candidate therapies are associated with the reduction in the risk of ascites and mortality after ascites development.

Comparing Costs and Outcomes of Treatments for Irritable Bowel Syndrome With Diarrhea: Cost-Benefit Analysis.

BACKGROUND: Irritable bowel syndrome (IBS) is one of the most expensive gastroenterological conditions and is an ideal target for developing a value-based care model. We assessed the comparative cost-benefit of treatments for IBS with diarrhea (IBS-D), the most common IBS subtype from insurer and patient perspectives. METHODS: We constructed a decision analytic model assessing trade-offs among guideline-recommended and recently FDA-approved drugs, supplements, low FODMAP diet, cognitive behavioral therapy (CBT). Outcomes and costs were derived from systematic reviews of clinical trials and national databases. Health-gains were represented using quality-adjusted life years (QALY). RESULTS: From an insurer perspective, on-label prescription drugs (rifaximin, eluxadoline, alosetron) were significantly more expensive than off-label treatments, low FODMAP, or CBT. Insurer treatment preferences were driven by average wholesale prescription drug prices and were not affected by health gains in sensitivity analysis within standard willingness-to-pay ranges up to $150,000/QALY-gained. From a patient perspective, prescription drug therapies and neuromodulators appeared preferable due to a reduction in lost wages due to IBS with effective therapy, and also considering out-of-pocket costs of low FODMAP food and out-of-pocket costs to attend CBT appointments. Comparative health outcomes exerted influence on treatment preferences from a patient perspective in cost-benefit analysis depending on a patients' willingness-to-pay threshold for additional health-gains, but health outcomes were less important than out-of-pocket costs at lower willingness-to-pay thresholds. CONCLUSIONS: Costs are critical determinants of IBS treatment value to patients and insurers, but different costs drive patient and insurer treatment preferences. Divergent cost drivers appear to explain misalignment between patient and insurer IBS treatment preferences in practice.

Budget impact of optimizing rifaximin-α use for the prevention of recurrent hepatic encephalopathy in The Netherlands.

AIMS: Rifaximin-α as an adjunct to lactulose is reimbursed in the Netherlands for prevention of the third and subsequent episodes of overt Hepatic Encephalopathy (HE) in cirrhotic patients. However, use of rifaximin-α remains limited. This study evaluates the clinical and economic impact of treating all patients eligible under Dutch reimbursement conditions with rifaximin-α as an adjunct to lactulose for the prevention of overt HE in the Netherlands from a hospital and healthcare payer's perspective. MATERIALS AND METHODS: A budget impact analysis was performed following national and international guidelines. Resource use was based on Dutch real-world data. HE-related cost inputs were based on the declaration codes, Dutch cost manual, and actual drug list prices. Several sensitivity and scenario analyses were conducted to assess model robustness. RESULTS: Treating eligible HE patients with rifaximin-α in addition to lactulose saves €4,487 and costs €249 per patient over a 5-year period compared with lactulose monotherapy from hospital and healthcare payer's perspectives, respectively. In the Netherlands, an estimated 38% of the 2,567 eligible patients are currently being treated with rifaximin-α. Optimizing rifaximin-α use by treating all eligible patients with the rifaximin-α + lactulose could save more than 3,000 hospital admissions, almost 15,000 hospital bed days, and 300 deaths over a 5-year period. Despite increased drug costs, treatment is estimated to result in potential cost savings over a 5-year period of 7.2 million euros from a Dutch hospital perspective. The budget impact is 397,770 euros from a healthcare payer's perspective. CONCLUSIONS: Next to a clinical perspective, also from an economic perspective, wider prescription of rifaximin-α adhering to guidelines could be beneficial to reduce costs from a hospital perspective. From a healthcare payer's perspective, costs increase with addition of rifaximin-α due to relative better survival causing relatively higher drug and liver transplantation-related costs.

Hospitalizations and healthcare costs associated with rifaximin versus lactulose treatment among commercially insured patients with hepatic encephalopathy in the United States.

AIMS: To assess healthcare costs and hospitalization rates associated with rifaximin therapy versus lactulose alone among patients at risk for hepatic encephalopathy (HE). METHODS AND MATERIALS: IBM Marketscan Commercial and Optum's de-identified Clinformatics Data Mart databases were used separately to identify commercially insured HE patients treated with rifaximin or lactulose alone, using an algorithm developed with clinical experts. HE-related hospitalizations were defined based on an algorithm using diagnosis codes and diagnosis-related group codes. HE-related/all-cause hospital admissions/days and healthcare costs were compared between rifaximin and lactulose episodes using incidence rate ratios and adjusted cost differences. RESULTS: In Marketscan, there were 13,515 [Optum: 5,217] rifaximin episodes and 9,946 [4,897] lactulose alone episodes included. Yearly rates of HE-related hospital admissions decreased by 33% [34%] when treated with rifaximin versus lactulose alone, and rates of HE-related hospital days similarly decreased by 43% [57%]. Yearly rates of all-cause hospital admissions decreased by 27% [27%]; rates of all-cause hospital days decreased by 33% [37%] during rifaximin episodes versus lactulose alone. This translated to $2,417 [$2,301] and $173 [$397] lower total mean medical costs and HE-related hospital costs per-patient-per-month, respectively (p < .05). Despite increased pharmacy costs associated with rifaximin, there was no change in total healthcare costs. Patients adherent to rifaximin incurred $2,891 [$2,340] lower total healthcare costs than non-adherent patients. In a simulated plan of 1 million lives, if 50% of HE patients treated with lactulose alone had rifaximin added on and were adherent to rifaximin therapy, the total cost savings would be $7.5 [$6.1] million per year ($0.62 [$0.50] per-member-per-month). CONCLUSIONS: Patients incurred significantly lower rates of HE-related and all-cause hospitalizations during rifaximin versus lactulose episodes, resulting in lower facility and professional costs. Cost savings may be possible if rifaximin adherence is improved in HE patients. LIMITATIONS: The study is subject to limitations common to claims-based analyses.

Cost-Effectiveness of Rifaximin Treatment in Patients with Hepatic Encephalopathy.

BACKGROUND: Hepatic encephalopathy (HE) is a complication of cirrhosis of the liver causing neuropsychiatric abnormalities. Clinical manifestations of overt HE result in increased health care resource utilization and effects on patient quality of life. While lactulose has historically been the mainstay of treatment for acute HE and maintenance of remission, there is an unmet need for additional therapeutic options with a favorable adverse event profile. Compared with lactulose alone, rifaximin has demonstrated proven efficacy in complete reversal of HE and reduction in the incidence of HE recurrence, mortality, and hospitalizations. Evidence suggests the benefit of long-term prophylactic therapy with rifaximin; however, there is a need to assess the economic impact of rifaximin treatment in patients with HE. OBJECTIVE: To assess the incremental cost-effectiveness of rifaximin ± lactulose versus lactulose monotherapy in patients with overt HE. METHODS: A Markov model was developed in Excel with 4 health states (remission, overt HE, liver transplantation, and death) to predict costs and outcomes of patients with HE after initiation of maintenance therapy with rifaximin ± lactulose to avoid recurrent HE episodes. Cost-effectiveness of rifaximin was evaluated through estimation of incremental cost per quality-adjusted life-year (QALY) or life-year (LY) gained. Analyses were conducted over a lifetime horizon. One-way deterministic and probabilistic sensitivity analyses were conducted to assess uncertainty in results. RESULTS: The rifaximin ± lactulose regimen provided added health benefits despite an additional cost versus lactulose monotherapy. Model results showed an incremental benefit of $29,161 per QALY gained and $27,762 per LY gained with rifaximin ± lactulose versus lactulose monotherapy. Probabilistic sensitivity analyses demonstrated that the rifaximin ± lactulose regimen was cost-effective ~99% of the time at a threshold of $50,000 per QALY/LY gained, which falls within the commonly accepted threshold for incremental cost-effectiveness. CONCLUSIONS: The clinical benefit of rifaximin, combined with an acceptable economic profile, demonstrates the advantages of rifaximin maintenance therapy as an important option to consider for patients at risk of recurrent HE. DISCLOSURES: This analysis was funded by Salix Pharmaceuticals, a division of Bausch Health US. Salix and Xcenda collaborated on the methods, and Salix, Xcenda, Jesudian, and Ahmad collaborated on the writing of the manuscript and interpretation of results. Bozkaya and Migliaccio-Walle are employees of Xcenda. Ahmad reports speaker fees from Salix Pharmaceuticals, unrelated to this study. Jesudian reports consulting and speaker fees from Salix Pharmaceuticals, unrelated to this study. The results from this model were presented at AASLD: The Liver Meeting 2014; November 7-11; Boston, MA.

A retrospective study of drug utilization and hospital readmissions among Medicare patients with hepatic encephalopathy.

Hepatic encephalopathy (HE) is a complication occurring in patients with cirrhosis and is associated with neuropsychiatric and motor abnormalities. Symptomatic HE episodes almost always require hospitalization and the frequent recurrence of episodes is associated with poor prognosis and increased medical costs. The utilization of existing therapies for management of HE and adherence to them has yet to be evaluated using real-world claims data.The aim of this study was to evaluate HE drug regimens and adherence and their association with hospital readmissions in Medicare Advantage plan patients.This was a retrospective cohort study of patients discharged from a HE-related hospitalization or emergency room visit. Based on subsequent enrollment in the plan they were categorized into cohorts of 1 month, 3, and 6 months follow-up, and medication regimen was evaluated within the first month. The drugs evaluated included lactulose, rifaximin, and neomycin. Multivariable logistic regression was conducted to evaluate the association of drug regimen and medication adherence measured as proportion of days covered with HE readmissions.There were 347 patients hospitalized for HE with 184 patients having 30-day enrollment and either a drug refill or an outpatient visit in this duration. Medications were not refilled by 67 (36.4%) patients. Various drug regimens had different adherence with mean (standard deviation) proportion of days covered ranging from 0.56 (0.29) to 0.82 (0.16) at 3 months and 0.48 (0.3) to 0.77 (0.15) at 6 months. The results of logistic regression at 3 and 6 months did not show a significant association of medication use or medication adherence with hospital readmissions.Despite availability of therapy, medication utilization was alarmingly low after discharge of patients from HE-related hospitalization. Medication adherence was also low, which may affect the rate of recurrence and costs associated with readmissions. Efforts are needed in both care coordination of these patients to ensure they are prescribed appropriate medications and to enhance adherence to them.

The Health Care Burden of Hepatic Encephalopathy.

Hepatic encephalopathy is a major neuropsychiatric complication of liver disease that affects 30% to 40% of cirrhotic patients. Hepatic encephalopathy is characterized by a brain dysfunction that is associated with neurologic complications. Those complications are associated with cognitive impairments, which negatively impacts patients' physical and mental health. In turn, hepatic encephalopathy poses a substantial economic and use burdens to the health care system. This article reviews the multidimensional aspects of the health care burden posed by hepatic encephalopathy.

Long-Term Management: Modern Measures to Prevent Readmission in Patients with Hepatic Encephalopathy.

Hepatic encephalopathy (HE) is a frequent indication for hospitalization and represents a common manifestation of portal hypertension and decompensated liver disease that contributes to hospital readmissions. Multiple new techniques are being evaluated to assist in preventing readmissions in these high-risk patients. Techniques to improve medication adherence are paramount. The use of telemedicine and on-demand patient assessment is likely to diminish hospitalizations for HE. Wearable technology has the potential to assist in HE diagnosis and prevent HE progression, with an anticipated diminution in hospital readmissions. This article discusses current and potential future techniques to improve outcomes in these vulnerable patients.

Social Impact of Hepatic Encephalopathy.

Hepatic encephalopathy (HE) is a multifaceted disorder, with effects stretching far beyond office visits and hospitalizations. Patients with HE suffer from varying degrees of altered consciousness, intellectual disability, and personality changes. A large social impact exists for patients with HE. Quality of life and activities of daily living, such as work capacity, driving ability, and sleep quality, have been shown to be affected. Additionally, caregiver and financial burdens are highly prevalent. Multiple tools exist to assess quality of life, including the CLD-Q questionnaire. Common treatments for HE, including rifaximin and lactulose, have been shown to improve overall quality of life.

Hepatic Encephalopathy Challenges, Burden, and Diagnostic and Therapeutic Approach.

Hepatic encephalopathy (HE) is an important cause of morbidity and mortality in patients with cirrhosis. The impact of HE on the health care system is similarly profound. The number of hospital admissions for HE has increased in the last 10-year period. HE is a huge burden to the patients, care givers, and the health care system. HE represents a "revolving door" with readmission, severely affects care givers, and has effects on cognition that can persists after liver transplant. This article reviews the current literature to discuss the challenges and diagnostic and therapeutic approaches to HE.

Value-based Pricing for Rifaximin Increases Access of Patients With Irritable Bowel Syndrome With Diarrhea to Therapy.

BACKGROUND & AIMS: Increasing drug prices lead to payer coverage restrictions, which limit access to therapy. We assessed the cost effectiveness of rifaximin in management of patients with irritable bowel syndrome with diarrhea (IBS-D) under common payer coverage restrictions and determined the maximum price at which rifaximin would be cost effective using contemporary cost-effectiveness thresholds. METHODS: A decision analytic model was constructed to evaluate quality of life, cost, and cost effectiveness of rifaximin for patients with IBS-D and complete noncoverage (insurer pays none of the drug cost), unrestricted access (insurer pays 100% of the drug cost), and formulary-restricted access (insurer pays 100% of the drug cost after for patients failed by initial therapy). The maximum cost-effective drug price was determined for each level of drug coverage using threshold analysis adjusted for willingness to pay thresholds from $50,000 to $150,000 per quality-adjusted life year (QALY). Analysis was performed from a payer perspective with a 1-year time horizon. RESULTS: Unrestricted and formulary-restricted access were more effective than complete non-coverage, resulting in additional 0.03 and 0.05 QALYs gained over noncoverage. However, unrestricted and formulary-restricted coverage were more expensive. At current drug prices, unrestricted or formulary-restricted coverage would cost an additional $1,207,136 or $171,850/QALY gained, compared to complete non-coverage. A 12% to 62% price reduction ($18.46 to $26.34/pill) for formulary-restricted access and 84% to 88% price reduction ($3.53 to $4.71/pill) for unrestricted access would be needed for rifaximin to be a cost-effective treatment strategy. Rifaximin retreatment intervals, response rates, and adverse events were important factors in sensitivity analysis. CONCLUSION: Using a decision analytic model, we show that payer coverage for rifaximin for patients with IBS-D exceeds generally accepted cost-effectiveness thresholds at current drug prices. Improved payer coverage could be justified using value-based pricing methods.

Evaluation of the cost-effectiveness of rifaximin-α for the management of patients with hepatic encephalopathy in the United Kingdom.

OBJECTIVE: Rifaximin-α 550 mg twice daily plus lactulose has demonstrated efficacy in reducing recurrence of episodes of overt hepatic encephalopathy (OHE) and the risk of hepatic encephalopathy (HE)-related hospitalizations compared with lactulose alone. This analysis estimated the cost effectiveness of rifaximin-α 550 mg twice daily plus lactulose versus lactulose alone in United Kingdom (UK) cirrhotic patients with OHE. METHOD: A Markov model was built to estimate the incremental cost-effectiveness ratio (ICER). The perspective was that of the UK National Health Service (NHS). Clinical data was sourced from a randomized controlled trial (RCT) and an open-label maintenance study in cirrhotic patients in remission from recurrent episodes of OHE. Health-related utility was estimated indirectly from disease-specific quality of life RCT data. Resource use data describing the impact of rifaximin-α on hospital admissions and length of stay for cirrhotic patients with OHE was from four single-center UK audits. Costs (2012) were derived from published sources; costs and benefits were discounted at 3.5%. The base-case time horizon was 5 years. RESULTS: The average cost per patient was £22,971 in the rifaximin-α plus lactulose arm and £23,545 in the lactulose arm, a saving of £573. The corresponding values for benefit were 2.35 quality adjusted life years (QALYs) and 1.83 QALYs per person, a difference of 0.52 QALYs. This translated into a dominant base-case ICER. Key parameters that impacted the ICER included number of hospital admissions and length of stay. CONCLUSION: Rifaximin-α 550 mg twice daily in patients with recurrent episodes of OHE was estimated to generate cost savings and improved clinical outcomes compared to standard care over 5 years.

Systematic Review of the Economic Burden of Overt Hepatic Encephalopathy and Pharmacoeconomic Impact of Rifaximin.

BACKGROUND: Hepatic encephalopathy (HE), a common neurologic complication in cirrhosis, is associated with substantial disease and economic burden. Rifaximin is a non-systemic antibiotic that reduces the risk of overt HE recurrence and overt HE-related hospitalizations. OBJECTIVE: Our objective was to provide an overview of the direct HE-related costs and cost benefits of rifaximin, lactulose, and rifaximin plus lactulose. METHODS: A systematic review of PubMed and relevant meeting abstracts was conducted to identify publications since 1 January 2007 reporting economic data related to HE and rifaximin and/or lactulose. Further, a public database and published literature were used to estimate current costs of hospitalization for overt HE, and potential cost savings of HE-related hospitalizations with rifaximin. The methodological quality of included studies was evaluated using the Drummond checklist. RESULTS: A total of 16 reports were identified for inclusion in the systematic review. Globally, HE-related direct costs ranged from $US5370 to $US50,120 annually per patient. Rifaximin was associated with shorter hospital stays and reduced healthcare costs. Rifaximin also has the potential to reduce overt HE-related hospitalization risk by 50% compared with lactulose. Rifaximin was shown to have a favourable pharmacoeconomic profile compared with lactulose (based on the incremental cost-effectiveness ratio). CONCLUSIONS: In addition to its clinical benefits (e.g. reduction in the risk of recurrence of overt HE, overt HE-related hospitalizations, favourable adverse event profile), economic data are favourable for the use of rifaximin in patients with a history of overt HE.