Length of stay and economic consequences with rivaroxaban vs enoxaparin/vitamin K antagonist in patients with DVT and PE: findings from the North American EINSTEIN clinical trial program

Objective:

Venous thromboembolism (VTE) (deep vein thrombosis [DVT] and pulmonary embolism [(PE]) represents a substantial economic burden to the healthcare system. Using data from the randomized EINSTEIN DVT and PE trials, this North American sub-group analysis investigated the potential of rivaroxaban to reduce the length of initial hospitalization in patients with acute symptomatic DVT or PE.

Methods:

A post-hoc analysis of hospitalization and length-of-stay (LOS) data was conducted in the North American sub-set of patients from the randomized, open-label EINSTEIN trial program. Patients received either rivaroxaban (15?mg twice daily for 3 weeks followed by 20?mg once daily; n?=?405) or dose-adjusted subcutaneous enoxaparin overlapping with (guideline-recommended ‘bridging’ therapy) and followed by a vitamin K antagonist (VKA) (international normalized ratio?=?2.0–3.0; n?=?401). The open-label study design allowed for the comparison of LOS between treatment arms under conditions reflecting normal clinical practice. LOS was evaluated using investigator records of dates of admission and discharge. Analyses were carried out in the intention-to-treat population using parametric tests. Costs were applied to the LOS based on weighted mean cost per day for DVT and PE diagnoses obtained from the Healthcare Cost and Utilization Project dataset.

Results:

Of 382 patients hospitalized, 321 (84%), had acute symptomatic PE; few DVT patients required hospitalization. Similar rates of VTE patients were hospitalized in the rivaroxaban and enoxaparin/VKA treatment groups, 189/405 (47%) and 193/401 (48%), respectively. In hospitalized VTE patients, rivaroxaban treatment produced a 1.6-day mean reduction in LOS (median?=?1 day) compared with enoxaparin/VKA (mean?=?4.5 vs 6.1; median?=?3 vs 4), translating to total costs that were $3419 lower in rivaroxaban-treated patients.

Conclusion:

In hospitalized North American patients with VTE, treatment with rivaroxaban produced a statistically significant reduction in LOS. When treating DVT and PE patients, clinicians should consider newer anti-coagulants with less complex treatment regimens.     

Cost-effectiveness analysis of rivaroxaban for treatment and secondary prevention of venous thromboembolism in the Netherlands

Background: Until recently, standard treatment of venous thromboembolism (VTE) concerned a combination of short-term low-molecular-weight heparin (LMWH) and long-term vitamin-K antagonist (VKA). Risk of bleeding and the requirement for regular anticoagulation monitoring are, however, limiting their use. Rivaroxaban is a novel oral anticoagulant associated with a significantly lower risk of major bleeds (hazard ratio?=?0.54, 95% confidence interval?=?0.37–0.79) compared to LMWH/VKA therapy, and does not require regular anticoagulation monitoring.

Aims: To evaluate the health economic consequences of treating acute VTE patients with rivaroxaban compared to treatment with LMWH/VKA, viewed from the Dutch societal perspective.

Methods: A life-time Markov model was populated with the findings of the EINSTEIN phase III clinical trial to analyze cost-effectiveness of rivaroxaban therapy in treatment and prevention of VTE from a Dutch societal perspective. Primary model outcomes were total and incremental quality-adjusted life years (QALYs), as well as life expectancy and costs.

Results: Over a patient’s lifetime, rivaroxaban was shown to be dominant, with health gains of 0.047 QALYs and cost savings of €304 compared to LMWH/VKA therapy. Dominance was robustly present in all sensitivity analyses. Major drivers of the differences between the two treatment arms were related to anticoagulation monitoring (medical costs, travel costs, and loss of productivity) and the occurrence of major bleeds.

Conclusion: Rivaroxaban treatment of patients with venous thromboembolism results in health gains and cost savings compared to LMWH/VKA therapy. This conclusion holds for the Dutch setting, both for the societal perspective, as well as the healthcare perspective.     

Cost and outcomes associated with rivaroxaban vs enoxaparin for the prevention of postsurgical venous thromboembolism from a US payer’s perspective

Abstract

Objective:

The objective of this analysis was the evaluation of the outcomes and costs associated with rivaroxaban and enoxaparin for the prevention of postsurgical venous thromboembolism (VTE) in patients undergoing total hip replacement (THR) and total knee replacement (TKR) from the US payer perspective.

Methods:

VTE event rates have been reported in three Phase III clinical trials that compared rivaroxaban and enoxaparin for VTE prevention after orthopedic surgery during the prophylaxis (≤35 days for THR patients and 10–14 days for TKR patients) and post-prophylaxis periods (≤90 days following surgery). These data were used in this decision-analytic model to estimate and compare health outcomes and costs associated with rivaroxaban and enoxaparin. The base-case analysis considered the number and costs of symptomatic VTE events during the prophylaxis period only. A 90-day horizon was considered in the sensitivity analysis.

Results:

Following THR, when extended durations of prophylaxis (35 days) were compared, rivaroxaban was associated with lower costs than enoxaparin, with total saving costs of $695/patient. When an extended duration of rivaroxaban prophylaxis (35 days) was compared with a short duration (10–14 days) of enoxaparin prophylaxis, rivaroxaban was estimated to prevent 9.9 additional symptomatic VTE events per 1000 patients, while saving $244/patient (rate/1000 patients). In the TKR population, short duration of rivaroxaban prophylaxis was estimated to prevent 13.1 additional symptomatic VTE events per 1000 patients. It was also less costly than short duration enoxaparin prophylaxis, with a saving of $411/patient (rate/1000 patients).

Limitations:

Only statistically significant differences were captured in the base-case economic analysis, and, therefore, differences in pulmonary embolism (PE) and bleeding events were not captured.

Conclusions:

In this model, rivaroxaban reduced total treatment payer costs vs enoxaparin for the prevention of VTE in THR or TKR patients.     

Cost-effectiveness of rivaroxaban in the prevention of venous thromboembolism: A Canadian analysis using the Ontario Ministry of Health Perspective

Abstract

Objectives:

A cost-effectiveness model for rivaroxaban evaluated the cost-effectiveness of prophylaxis with rivaroxaban (a once-daily, orally administered Factor Xa inhibitor) vs enoxaparin in the prevention of venous thromboembolism (VTE) after total hip replacement (THR) and total knee replacement (TKR). This Canadian analysis was conducted using the Ontario Ministry of Health perspective over a 5-year time horizon. The model combined clinical data and builds upon existing economic models.

Methods:

The model included both acute VTE (represented as a decision tree) and long-term complications (represented as a Markov process with 1-year cycles) phases. The model allowed VTE event rates, quality-adjusted life expectancy and direct medical costs to be estimated over a 5-year time horizon, based on current approved practice patterns in Canada. A number of one-way sensitivity analyses were performed on the baseline assumptions, including a comparison of rivaroxaban with dalteparin, and probabilistic sensitivity analyses were performed to address any uncertainty concerning model inputs.

Results:

When comparing equal durations of therapy, rivaroxaban dominated enoxaparin in the prevention of VTE events in patients undergoing THR and TKR, providing more benefit at a lower cost. Rivaroxaban was cost-effective when comparing 35 days’ prophylaxis with 14 days’ prophylaxis with enoxaparin following THR. One-way and probabilistic sensitivity analyses demonstrated that the results of the economic analysis were robust to variations in key inputs. Rivaroxaban remained dominant during one-way sensitivity analyses comparing rivaroxaban with dalteparin after THR or TKR.

Limitations:

Although clinical trial data were used in the prophylaxis module, assumptions and values used in the post-prophylaxis and long-term complication (LTC) modules were based on several different literature sources; it was not always possible to source Canadian data.

Conclusions:

This economic analysis suggests that the use of rivaroxaban for the prophylaxis of VTE after THR or TKR in Canada was cost-effective.     

Cost-effectiveness of rivaroxaban versus apixaban for the initial treatment of venous thromboembolism and extended prevention of recurrences in the UK

Abstract

Aim: To evaluate the relative cost-effectiveness of using rivaroxaban vs apixaban for the initial treatment plus extended prevention of venous thromboembolism (VTE) in the UK. Extended prevention was assessed using a 10-mg rivaroxaban dose, as the 20-mg dose has already been evaluated.

Methods: A Markov model compared the health outcomes and costs of treating VTE patient cohorts with either rivaroxaban (15?mg twice daily for 3 weeks, followed by 20?mg once daily for 6 months, then extended prevention with 10?mg once daily) or apixaban (10?mg twice daily for 1 week, followed by 5?mg twice daily for 6 months, then extended prevention with 2.5?mg twice daily) over a lifetime horizon. The model included an initial acute treatment and prevention phase (0–6?months) and an extended prevention phase (6–18 months). Efficacy and safety data were derived from two network meta-analyses. Reference treatment comparators were derived from the EINSTEIN-Pooled study and EINSTEIN-CHOICE trial. Healthcare costs and utility data were derived from published literature.

Results: The rivaroxaban regimen was associated with increased quality-adjusted life years (QALYs) and slightly lower total costs compared with apixaban over a lifetime horizon. Deterministic and probabilistic sensitivity analyses demonstrated that rivaroxaban remained a cost-effective alternative to apixaban over a wide range of parameters. Incremental cost-effectiveness ratio estimates were below the £20,000 per QALY threshold in 74.1% of 2,000 model simulations. Scenario analyses further supported that rivaroxaban is a cost-effective alternative to apixaban.

Limitations: Clinical and safety inputs were derived from network meta-analysis, which are subject to inherent limitations whereby small differences between study designs may severely impact efficacy and safety outcomes. Furthermore, these inputs were based on data from clinical trials, which may not reflect real-world data.

Conclusions: Rivaroxaban was associated with a slightly lower total cost and increased QALYs compared with apixaban for VTE management in the UK over a lifetime horizon.     

Costs of hospital visits among patients with deep vein thrombosis treated with rivaroxaban and LMWH/warfarin

Background:

For many years, the standard of care for patients diagnosed with deep vein thrombosis (DVT) has been low-molecular-weight heparin (LMWH) bridging to an oral Vitamin-K antagonist (VKA). The availability of new non-VKA oral anticoagulants (NOAC) agents as monotherapy may reduce the likelihood of hospitalization for DVT patients.

Objective:

To compare hospital visit costs of DVT patients treated with rivaroxaban and LMWH/warfarin.

Methods:

A retrospective claim analysis was conducted using the MarketScan Hospital Drug Database for care provided between January 2011 and December 2013. Adult patients using rivaroxaban or LMWH/warfarin with a primary diagnosis of DVT during the first day of a hospital visit were identified (i.e., index hospital visit). Based on propensity-score methods, historical LMWH/warfarin patients (i.e., patients who received LMWH/warfarin before the approval of rivaroxaban) were matched 4:1 to rivaroxaban patients. The hospital-visit cost difference between these groups was evaluated for the index hospital visit, as well as for total hospital-visit costs (i.e., including index and subsequent hospital visit costs).

Results:

All rivaroxaban users (n?=?134) in the database were well-matched with four LMWH/warfarin users (n?=?536). The mean hospital-visit costs were $5257 for the rivaroxaban cohort and $6764 in the matched-cohort of patients using LMWH/warfarin. The $1508 cost difference was statistically significant between cohorts (95% CI?=?[?$2296; ?$580]; p-value?=?0.002). Total hospital-visit costs were lower for rivaroxaban compared to LMWH/warfarin users within 1, 2, 3, and 6 months after index visit (significantly lower within 1 and 3 months, p-values <0.05)

Limitations:

Limitations were inherent to administrative-claims data, completeness of baseline characteristics, adjustments restricted to observational factors, and lastly the sample size of the rivaroxaban cohort.

Conclusion:

The availability of rivaroxaban significantly reduced the costs of hospital visits in patients with DVT treated with rivaroxaban compared to LMWH/warfarin.     

Clinical and economic benefits of extended treatment with apixaban for the treatment and prevention of recurrent venous thromboembolism in Canada

Background and objective Venous thromboembolism (VTE) is associated with long-term clinical and economic burden. Clinical guidelines generally recommend at least 3 months of anticoagulation, but, in clinical practice, concerns over bleeding risk often limit extended treatment. Apixaban was studied for extended VTE treatment in the AMPLIFY-EXT trial, demonstrating superiority to placebo in VTE reduction without increasing risk of major bleeding. This study assessed the long-term clinical and economic benefits of extending treatment with apixaban when clinical equipoise exists compared to standard of care with enoxaparin/warfarin and other novel oral anti-coagulants (NOACs) for the treatment and prevention of recurrent VTE in Canada.

Methods A Markov model was developed to follow patients with VTE over their lifetimes. Efficacy and safety for apixaban and enoxaparin/warfarin were based on AMPLIFY and AMPLIFY-EXT, while relative efficacy to other NOACs was synthesized by network meta-analysis (NMA). Dosages for NOACs and enoxaparin/warfarin were based on their respective trials and were given up to 18 months and up to 6 months, followed by no treatment, respectively. Patient quality adjusted life years (QALYs) were based on published studies, and costs for resource utilization were from a Ministry of Health perspective, expressed as 2014 CAD ($).

Results Extended treatment with apixaban compared to enoxaparin/warfarin resulted in fewer recurrent VTEs, VTE-related deaths, and bleeding events, but at slightly increased cost. The incremental cost-effectiveness ratio was $4828 per QALY gained. Compared to other NOACs, apixaban had the fewest bleeding events, similar recurrent VTE events, and the lowest overall cost, which was driven by the strong bleeding profile. In scenario analyses of acute and lifetime treatments, apixaban was cost-effective against all strategies.

Conclusions Extended treatment with apixaban can offer substantial clinical benefits and is a cost-effective alternative to enoxaparin/warfarin and other NOACs.     

An indirect comparison,via enoxaparin,of rivaroxaban with dabigatran in the prevention of venous thromboembolism after hip or knee replacement

Abstract

Objective:

To compare the efficacy, in the prevention of venous thromboembolism (VTE), and safety, of rivaroxaban and dabigatran relative to the common comparator enoxaparin.

Methods:

Two randomized clinical trials of dabigatran, one after total hip replacement (THR), RE-NOVATE, and one after total knee replacement (TKR), RE-MODEL, were identified as using the same enoxaparin regimen (40?mg once daily given the evening before surgery) and being of comparable duration to two rivaroxaban trials, RECORD1 and RECORD3. Indirect comparisons were performed on both efficacy and safety endpoints. To enable comparisons, symptomatic VTE results were based on the total study duration period, i.e. including the follow-up period. Major bleeding included surgical-site bleeding events.

Results:

After THR, rivaroxaban 10?mg once daily significantly reduced total VTE and symptomatic VTE relative to dabigatran 220?mg once daily (relative risk 0.34 and 0.19, respectively). After TKR, rivaroxaban significantly reduced total VTE versus dabigatran (relative risk 0.53); symptomatic VTE was not different between dabigatran and rivaroxaban. There was no significant difference in the rates of major bleeding for patients receiving rivaroxaban or dabigatran.

Conclusions:

Based on the indirect comparisons, rivaroxaban was estimated to be more efficacious than dabigatran in the prevention of total VTE after THR and TKR. Our analysis relied upon published data for dabigatran and did not have the advantages of more detailed comparative data obtained directly from a randomized trial, as was the case with rivaroxaban. Further comparative research may be of value, but until available our conclusions represent the best available evidence.     

A cost-analysis model for anticoagulant treatment in the hospital setting

Background:

Rivaroxaban is the first oral factor Xa inhibitor approved in the US to reduce the risk of stroke and blood clots among people with non-valvular atrial fibrillation, treat deep vein thrombosis (DVT), treat pulmonary embolism (PE), reduce the risk of recurrence of DVT and PE, and prevent DVT and PE after knee or hip replacement surgery. The objective of this study was to evaluate the costs from a hospital perspective of treating patients with rivaroxaban vs other anticoagulant agents across these five populations.

Methods:

An economic model was developed using treatment regimens from the ROCKET-AF, EINSTEIN-DVT and PE, and RECORD1-3 randomized clinical trials. The distribution of hospital admissions used in the model across the different populations was derived from the 2010 Healthcare Cost and Utilization Project database. The model compared total costs of anticoagulant treatment, monitoring, inpatient stay, and administration for patients receiving rivaroxaban vs other anticoagulant agents. The length of inpatient stay (LOS) was determined from the literature.

Results:

Across all populations, rivaroxaban was associated with an overall mean cost savings of $1520 per patient. The largest cost savings associated with rivaroxaban was observed in patients with DVT or PE ($6205 and $2742 per patient, respectively). The main driver of the cost savings resulted from the reduction in LOS associated with rivaroxaban, contributing to ～90% of the total savings. Furthermore, the overall mean anticoagulant treatment cost was lower for rivaroxaban vs the reference groups.

Limitations:

The distribution of patients across indications used in the model may not be generalizable to all hospitals, where practice patterns may vary, and average LOS cost may not reflect the actual reimbursements that hospitals received.

Conclusion:

From a hospital perspective, the use of rivaroxaban may be associated with cost savings when compared to other anticoagulant treatments due to lower drug cost and shorter LOS associated with rivaroxaban.     

Healthcare resource utilization and costs associated with venous thromboembolism in cancer patients treated with anticoagulants

Abstract

Objective: The standard of care for cancer-related venous thromboembolism (VTE) has been low molecular weight heparin (LMWH), but oral anticoagulants are also widely prescribed. This study compared VTE-related healthcare resource utilization and costs of cancer patients treated with anticoagulants.

Methods: Claims data from Humana Database (January 1, 2013–May 31, 2015) were analyzed. Based on the first anticoagulant received, patients were classified into LMWH, warfarin, or rivaroxaban cohorts. Characteristics were evaluated during the 6 months pre-index date (i.e. the first VTE); VTE-related resource utilization and costs were evaluated during follow-up. Cohorts were compared using rate ratios, and p-values and 95% confidence intervals were calculated. Healthcare costs were evaluated per-patient-per-year (PPPY) and compared using mean cost differences.

Results: A total of 2,428 patients (LMWH: n?=?660; warfarin: n?=?1,061; rivaroxaban: n?=?707) were included. Compared to patients treated with LMWH, patients treated with rivaroxaban had significantly fewer VTE-related hospitalizations, hospitalization days, and emergency room and outpatient visits, resulting in an increase of $12,000 VTE-related healthcare costs PPPY with LMWH vs rivaroxaban. Patients treated with rivaroxaban had significantly lower VTE-related resource utilization compared to patients treated with warfarin; however, VTE-related costs were similar between cohorts. The higher drug costs ($1,519) were offset by significantly lower outpatient (?$1,039) and hospitalization costs (?$522) in rivaroxaban relative to the warfarin cohort.

Conclusions: Healthcare resource use and costs associated with VTE treatment in cancer patients are highest with LMWH relative to warfarin and rivaroxaban.     

Rivaroxaban for non-valvular atrial fibrillation and venous thromboembolism in the Netherlands: a real-world data based cost-effectiveness analysis

Background: Non-vitamin K antagonist oral anticoagulants (NOACs) have been included in international guidelines as important alternatives to vitamin K antagonists (VKAs) for the treatment of venous thromboembolism (VTE) and stroke prevention in non-valvular atrial fibrillation (NVAF). Meanwhile, in the Netherlands, NOACs are widely used next to VKAs. The objective of this study is to estimate the cost-effectiveness of treatment with rivaroxaban compared to VKAs in NVAF and VTE patients in the Netherlands, using data from international prospective observational phase IV studies.

Methods: Two models were developed to represent NVAF and VTE patients, populated with patients from the XANTUS (NCT01606995) and XALIA (NCT01619007) international prospective observational studies. The 1-year cost-effectiveness of rivaroxaban use, compared to VKAs, was explored in a population consisting of NVAF and VTE patients (base case) as well as for four scenarios with sub-populations: NVAF patients only, VTE patients only, NVAF patients with unstable international normalized ratio (INR), and NVAF patients using an INR self-measuring device.

Results: In the base case, rivaroxaban saved €72,350 and gained 21 quality-adjusted life-years (QALYs) in a simulation of 2,000 patients over the use of VKAs. Ergo, rivaroxaban was dominant over VKAs. The probabilistic sensitivity analysis showed a probability of 85% for rivaroxaban being dominant and 100% at a willingness-to-pay threshold of €20,000/QALY. Rivaroxaban appeared to be dominant in all scenarios as well, except for the NVAF-patients-only scenario where the incremental cost-effectiveness ratio (ICER) was €157/QALY.

Conclusions: In patients with NVAF or VTE, rivaroxaban treatment is likely to be cost-effective and a potentially cost-saving alternative to VKA in the Netherlands.     

Evaluation of medical costs associated with use of new oral anticoagulants compared with standard therapy among venous thromboembolism patients

Objective:

This study evaluated differences in medical costs associated with clinical end-points from randomized clinical trials that compared the new oral anticoagulants (NOACs), dabigatran, rivaroxaban, apixaban, and edoxaban, to standard therapy for treatment of patients with venous thromboembolism (VTE).

Research design and methods:

Event rates of efficacy and safety end-points from the clinical trials (RE-COVER, RE-COVER II, EINSTEIN-Pooled, AMPLIFY, Hokusai-VTE trial) were obtained from published literature. Incremental annual medical costs among patients with clinical events from a US payer perspective were obtained from the literature or healthcare claims databases and inflation adjusted to 2013 costs. Differences in total medical costs associated with clinical end-points for the NOACs vs standard therapy were then estimated. One-way and Monte Carlo sensitivity analyses were carried out.

Results:

A lower rate of major bleedings was associated with use of any of the NOACs vs standard therapy. Except for dabigatran, use of NOACs was also associated with a lower rate of recurrent VTE/death. As a result of the reduction in clinical event rates, the overall medical cost differences were ?$146, ?$482, ?$918, and ?$344 for VTE patients treated with dabigatran, rivaroxaban, apixaban, and edoxaban, respectively, vs patients treated with standard therapy.

Conclusions:

When any of the four NOACs are used instead of standard therapy for acute VTE, treatment medical costs are reduced. Apixaban is associated with the greatest reduction in medical costs, which is driven by medical cost reductions associated with both efficacy and safety end-points. Further evaluation may be needed to validate these results in the real-world setting.     

Cost comparison of continued anticoagulation with rivaroxaban versus placebo based on the 1-year EINSTEIN-Extension trial efficacy and safety results

Aims: The EINSTEIN-Extension trial (EINSTEIN-EXT) found that continued treatment with rivaroxaban for an additional 6 or 12 months (vs placebo) after 6–12 months of initial anticoagulation significantly reduced the risk of recurrent venous thromboembolism (VTE) with a small non-significant increased risk of major bleeding (none fatal or in critical site). This study aimed to compare total healthcare cost between rivaroxaban and placebo, based on the EINSTEIN-EXT event rates.

Methods: Total healthcare cost was calculated as the sum of treatment and clinical event costs from a US managed care perspective. Treatment duration and event rates were obtained from the EINSTEIN-EXT study. Adjustment on treatment duration was made by assuming a 10% non-adherence rate. Drug costs were based on wholesale acquisition costs. Cost estimates for clinical events (i.e. recurrent deep vein thrombosis [DVT], recurrent pulmonary embolism, major bleeding, clinically relevant non-major bleeding) were determined from the literature. Results were examined over a ±20% range of each cost component and over 95% confidence intervals (CIs) of event rate differences in deterministic (one-way) and probabilistic sensitivity analyses (PSA).

Results: Total healthcare cost was $1,454 lower for rivaroxaban-treated (vs placebo-treated) patients in the base-case, with a lower clinical event cost fully offsetting drug cost. The cost savings of recurrent DVT alone (–$3,102) was greater than drug cost ($2,723). Total healthcare cost remained lower for rivaroxaban in the majority (73%) of PSA (cost difference [95% CI]?=?–$1,454 [–$2,396, $1,231]).

Limitations: This study was conducted over the 1-year observation period of the EINSTEIN-EXT trial, which limited “real-world” applicability and examination of long-term economic impact. Assumptions on drug and clinical event costs were US-based and, thus, not applicable to other healthcare systems.

Conclusions: Total healthcare costs were estimated to be lower for patients continuing rivaroxaban therapy compared to those receiving placebo in VTE patients who had completed 6–12 months of VTE treatment.     

Cost-effectiveness model of abiraterone plus prednisone,cabazitaxel plus prednisone and enzalutamide for visceral metastatic castration resistant prostate cancer therapy after docetaxel therapy resistance

Abstract

Aims: Among patients diagnosed with prostate cancer, 10–20% will develop castration-resistant prostate cancer (CRPC) within 5?years; for 70%, CRPC will metastasize, mostly to the lungs and/or liver. We performed a cost-effectiveness model comparing abiraterone plus prednisone (ABI?+?PRD), cabazitaxel plus prednisone (CAB?+?PRD) and enzalutamide (ENZ) for visceral metastatic CRPC post-docetaxel therapy resistance.

Methods: A three-state (Progression-Free, Progression, Death) lifetime Markov model was constructed to compare ABI?+?PRD, CAB?+?PRD, and ENZ from a United States healthcare payer perspective (2019?US$; discount rate 3%/yr.). Effectiveness was measured in life-years (LYs) and quality-adjusted life years (QALYs). Inputs included treatment costs, grade III/IV adverse events with incidence ≥5%, physician follow-up, lab and imaging tests. Phase III trial Kaplan-Meier curves were extrapolated to estimate overall survival and Progression-Free transition probabilities. Incremental cost-effectiveness ratios (ICERs) and utility ratios (ICURs), probabilistic sensitivity analyses (PSAs) and cost-effectiveness acceptability curves at willingness-to-pay (WTP) thresholds were estimated.

Results: Models estimated 3-year overall survival rates of 1.3% for patients treated with ABI?+?PRD, 16.2% for CAB?+?PRD, and 13.2% for ENZ. Estimated Progression-Free rates at 1.5?years were 0.51% for ABI?+?PRD, 0.27% for CAB?+?PRD, and 14.47% for ENZ. LYs and QALYs were 1.20 and 0.58 respectively for ABI?+?PRD, 1.48 and 0.56 for CAB?+?PRD, and 1.58 and 0.79 for ENZ. Total treatment costs were: $115,433 for ABI?+?PRD, $85,337 for CAB?+?PRD and $109,213 for ENZ. CAB?+?PRD and ENZ dominated ABI?+?PRD due to higher LYs gained. Incremental QALYs for ENZ vs. CAB?+?PRD were larger than incremental LYs. The ICUR for ENZ was $103,674/QALY compared to CAB?+?PRD.

Conclusions: This analysis found ENZ provided greater LYs and QALYs than both ABI?+?PRD and CAB?+?PRD, at a lower cost than ABI?+?PRD, but at a higher cost compared to CAB?+?PRD. For patients with visceral mCRPC after docetaxel therapy resistance, ENZ was cost-effective 92% of the time with a WTP threshold of $100,000/QALY.     

Cost-effectiveness of rivaroxaban versus warfarin for stroke prevention in non-valvular atrial fibrillation in the Japanese healthcare setting

Abstract

Aims: This article aimed to examine the cost-effectiveness of rivaroxaban in comparison to warfarin for stroke prevention in Japanese patients with non-valvular atrial fibrillation (NVAF), from a public healthcare payer’s perspective.

Materials and methods: Baseline event risks were obtained from the J-ROCKET AF trial and the treatment effect data were taken from a network meta-analysis. The other model inputs were extracted from the literature and official Japanese sources. The outcomes included the number of ischaemic strokes, myocardial infarctions, systemic embolisms and bleedings avoided, life-years, quality-adjusted life-years (QALYs), incremental costs and incremental cost-effectiveness ratio (ICER). The scenario analysis considered treatment effect data from the same network meta-analysis.

Results: In comparison with warfarin, rivaroxaban was estimated to avoid 0.284 ischaemic strokes per patient, to increase the number of QALYs by 0.535 per patient and to decrease the total costs by ¥118,892 (€1,011.11) per patient (1 JPY = 0.00850638 EUR; XE.com, 7 October 2019). Consequently, rivaroxaban treatment was found to be dominant compared to warfarin. In the scenario analysis, the ICER of rivaroxaban versus warfarin was ¥2,873,499 (€24,446.42) per QALY.

Limitations: The various sources of data used resulted in the heterogeneity of the cost-effectiveness analysis results. Although, rivaroxaban was cost-effective in the majority of cases.

Conclusion: Rivaroxaban is cost-effective against warfarin for stroke prevention in Japanese patients with NVAF, giving the payer WTP of 5,000,000 JPY.     

Cost effectiveness of atazanavir-ritonavir versus lopinavir-ritonavir in treatment-naïve human immunodeficiency virus-infected patients in the United States

Abstract

Objective:

To evaluate lifetime cost effectiveness of atazanavir-ritonavir (ATV?+?r) versus lopinavir-ritonavir (LPV/r), both with tenofovir-emtricitabine, in US HIV-infected patients initiating first-line antiretroviral therapy.

Methods:

A Markov microsimulation model was developed to calculate quality-adjusted life-years (QALYs) based on CD4 and HIV RNA levels, coronary heart disease (CHD), AIDS, opportunistic infections (OIs), diarrhea, and hyperbilirubinemia. A million-member cohort of HIV-1-infected, treatment-naïve adults progressed at 3-month intervals through eight health states. Baseline characteristics, virologic suppression, cholesterol changes, and diarrhea and hyperbilirubinemia rates were based on 96-week CASTLE trial results. HIV mortality, OI rates, adherence, costs, utilities, and CHD risk were from literature and experts.

Limitations:

The incremental cost-effectiveness ratio (ICER) may be overestimated because the ATV?+?r treatment effect was based on an intention-to-treat analysis. The QALY weights used for diarrhea, hyperbilirubinemia, and CHD events are uncertain; however, the ICER remained <$50,000/QALY when these values were varied in sensitivity analyses.

Results:

ATV?+?r patients received first-line therapy longer than LPV/r patients (97.3 vs. 70.7 months), had longer quality-adjusted survival (11.02 vs. 10.76 years), similar overall survival (18.52 vs. 18.51 years), and higher costs ($275,986 vs. 269,160). ATR?+?r patients had lower rates of AIDS (19.08 vs. 20.05 cases/1,000 patient-years), OIs (0.44 vs. 0.52), diarrhea (1.27 vs. 6.26), and CHD events (5.44 vs. 5.51), but higher hyperbilirubinemia rates (6.99 vs. 0.25). ATV?+?r added 0.26 QALYs at a cost of $6826, for $26,421/QALY.

Conclusions:

By more effectively reducing viral load with less gastrointestinal toxicity and a better lipid profile, ATV?+?r lowered rates of AIDS and CHD, increased quality-adjusted survival, and was cost effective (<$50,000/QALY) compared with LPV/r.     

Medical costs in the US of clinical events associated with oral anticoagulant (OAC) use compared to warfarin among non-valvular atrial fibrillation patients ≥75 and <75 years of age,based on the ARISTOTLE,RE-LY,and ROCKET-AF trials

Abstract

Objectives:

Based on clinical trials the oral anticoagulants (OACs) apixaban, dabigatran, and rivaroxaban are efficacious for reducing stroke risk for non-valvular atrial fibrillation (NVAF) patients. Based on the clinical trials, this study evaluated the medical costs for clinical events among NVAF patients ≥75 and <75 years of age treated with individual OACs vs warfarin.

Methods:

Rates for primary and secondary efficacy and safety outcomes (i.e., clinical events) among NVAF patients receiving warfarin or each of the OACs were determined for NVAF populations aged ≥75 years and <75 years of age from the OAC vs warfarin trials. One-year incremental costs among patients with clinical events were obtained from published literature and inflation adjusted to 2010 costs. Medical costs, excluding medication costs, for clinical events associated with each OAC and warfarin were then estimated and compared.

Results:

Among NVAF patients aged ≥75, compared to warfarin, use of either apixaban or rivaroxaban was associated with a reduction in medical costs per patient year (apixaban?=??$825, rivaroxaban?=?$23), while dabigatran use was associated with increased medical costs of $180 per patient year. Among NVAF patients <75 years of age medical costs per patient year were estimated to be reduced ?$254, ?$367, and ?$88, for apixaban, dabigatran, and rivaroxaban, respectively, in comparison to warfarin.

Limitations:

This economic analysis was based on clinical trial data and, therefore, the direct application of the results to routine clinical practice will require further assessment.

Conclusions:

Difference in medical costs between OAC and warfarin treated NVAF patients vary by age group and individual OACs. Although reductions in medical costs for NVAF patients aged ≥75 and <75 were observed for those using either apixaban or rivaroxaban vs warfarin, the reductions were greater per patient year for both the older and younger NVAF populations using apixaban.     

Cost-effectiveness of daclatasvir plus sofosbuvir-based regimen for treatment of hepatitis C virus genotype 3 infection in Canada

Objective:

New regimens for the treatment of chronic hepatitis C virus (HCV) genotype 3 have demonstrated substantial improvement in sustained virologic response (SVR) compared with existing therapies, but are considerably more expensive. The objective of this study was to evaluate the cost-effectiveness of two novel all-oral, interferon-free regimens for the treatment of patients with HCV genotype 3: daclatasvir plus sofosbuvir (DCV?+?SOF) and sofosbuvir plus ribavirin (SOF?+?RBV), from a Canadian health-system perspective.

Methods:

A decision analytic Markov model was developed to compare the effect of various treatment strategies on the natural history of the disease and their associated costs in treatment-naïve and treatment-experienced patients. Patients were initially distributed across fibrosis stages F0–F4, and may incur disease progression through fibrosis stages and on to end-stage liver disease complications and death; or may achieve SVR. Clinical efficacy, health-related quality-of-life, costs, and transition probabilities were based on published literature. Probabilistic sensitivity analysis was performed to assess parameter uncertainty associated with the analysis.

Results:

In treatment-naive patients, the expected quality-adjusted life years (QALYs) for interferon-free regimens were higher for DCV?+?SOF (12.37) and SOF?+?RBV (12.48) compared to that of pINF?+?RBV (11.71) over a lifetime horizon, applying their clinical trial treatment durations. The expected costs were higher for DCV?+?SOF ($170,371) and SOF?+?RBV ($194,776) vs pINF?+?RBV regimen ($90,905). Compared to pINF?+?RBV, the incremental cost-effectiveness ratios (ICER) were $120,671 and $135,398 per QALYs for DCV?+?SOF and SOF?+?RBV, respectively. In treatment-experienced patients, DCV?+?SOF regimen dominated the SOF?+?RBV regimen. Probabilistic sensitivity analysis indicated a 100% probability that a DCV?+?SOF regimen was cost saving in treatment-experienced patients.

Conclusion:

Daclatasvir plus sofosbuvir is a safe and effective option for the treatment of chronic HCV genotype 3 patients. This regimen could be considered a cost-effective option following a first-line treatment of peg-interferon/ribavirin treatment experienced patients with HCV genotype-3 infection.     

Risks and cost burden of venous thromboembolism and bleeding for patients undergoing total hip or knee replacement in a managed-care population

Abstract

Background:

Total hip and total knee replacement (THR/TKR) patients are at increased risk of developing venous thromboembolism (VTE). VTE prevention using anticoagulation therapy increases the risk of bleeding. Therefore, any assessment of the cost of VTE and its prevention should also take into consideration risks and costs of bleeding.

Objective:

To assess the risks of developing VTE and bleeding in patients after THR or TKR given real-world use of thromboprophylaxis, and to quantify the incremental cost associated with each.

Methods:

Analyses of insurance healthcare claims from the Ingenix IMPACT National Managed Care Database^TM from January 2004 to December 2008 were conducted. Subjects were ≥18 years and had ≥1 procedure code for THR or TKR. Patients had to have ≥180 days of observation prior to surgery and were observed for ≤3 months after THR or TKR. VTE was defined as ≥1 diagnosis code for deep vein thrombosis or pulmonary embolism. Bleeding events were classified as major or non-major. Risks of VTE or bleeding events were calculated as number of patients with an event divided by number of patients with the procedure. Incremental all-cause healthcare costs associated with VTE or bleeding were calculated as the difference between cohorts of patients without VTE or bleeding matched 1:1 to patients with VTE or bleeding.

Results:

Of 119,729 patients (43,670 THR and 76,059 TKR), 7974 had a VTE event and 4849 had a bleeding event (2216 major bleeding [a subset of ‘any bleeding’]). The risks of VTE, any bleeding, and major bleeding were 6.7, 4.0, and 1.9 events, respectively, per 100 patients. Up to 3 months after THR/TKR, mean incremental all-cause healthcare costs per patient per month associated with VTE, bleeding, and major bleeding were $2729, $2696, and $4304, respectively. Total monthly costs versus matched controls over 3 months were: VTE: $12,333 vs. $9604; any bleeding: $12,481 vs. $9785; major bleeding: $14,015 vs. $9710; p?<?0.001 for all.

Limitations:

Key limitations included potential inaccuracies or omissions in procedures, diagnoses, or costs of claims data; lack of information on the amount of blood transfused or decreases in the hemoglobin level to evaluate the severity of a bleeding event; and potential biases due to the observational design of the study.

Conclusion:

From the managed-care population perspective, in THR/TKR patients the greater incidence of VTE compared to any bleeding and major bleeding translated into a higher cumulative cost burden.