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

A Prospective Randomized Controlled Trial Comparing Enoxaparin & Rivaroxaban for Venous Thromboembolism Prophylaxis in Orthopaedic Trauma

OBJECTIVES

To determine whether there is a difference in orthopaedic trauma patient medication satisfaction and adherence using an oral versus subcutaneous injectable anticoagulant for venous thromboembolism chemoprophylaxis.

DESIGN

Randomized controlled trial.

SETTING

Single academic Level 1 trauma center.

PARTICIPANTS

One hundred twenty adult orthopaedic trauma patients with operative pelvic or lower extremity fractures were randomized and completed the study.

INTERVENTION

Three weeks of either the service standard 40 mg once daily enoxaparin versus trial medication 10 mg once daily rivaroxaban postoperatively.

MAIN OUTCOME MEASURES

Patient satisfaction as measured by the Treatment Satisfaction Questionnaire for Medication (TSQM-9). Medication adherence as measured by the Morisky Medication Adherence Scale (MMAS-8).

RESULTS

Medication adherence was similar in both groups. Medication satisfaction was significantly higher in the oral rivaroxaban group based on the TSQM-9 and patient-reported data. Secondary outcomes found no significant difference in the incidence of bleeding events or clinically relevant venous thromboembolism. The enoxaparin group experienced more adverse medication-related events. The rivaroxaban medication regimen costs 7.5-10× less out of pocket for uninsured patients.

CONCLUSION

The results of this randomized controlled trial demonstrate that patients with surgical orthopaedic trauma prefer an oral anticoagulant for postoperative venous thromboembolism chemoprophylaxis and suggest that rivaroxaban may be a viable option. Furthermore, large-scale studies are needed to confirm safety and efficacy for rivaroxaban in this population as a potential alternative to enoxaparin and aspirin.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Economic Evaluation of New Oral Anticoagulants in Prevention of Venous Thrombosis Following Joint Replacement Surgery: A Systematic Review

PURPOSE

The main purpose of prescribing oral anticoagulants in patients undergoing total knee and total hip replacement surgery is to prevent venous thromboembolism (VTE). The present study aimed to summarize evidence from economic evaluations regarding new oral anticoagulants (NOACs) used in VTE prophylaxis after joint replacement surgery.

METHODS

To obtain relevant literature on economic evaluations of NOACs used in the prevention of VTE following joint replacement surgery, we searched the Cochrane Library, PubMed, Web of Science, Embase, and Scopus, as well as specialized economic evaluation databases, for articles published from January 2008 to December 2019. Next, 2 reviewers screened the titles and abstracts of studies, extracted data from the full-text articles, and assessed the quality of the methodologies using the Quality of Health Economic Studies checklist.

FINDINGS

Twenty-eight studies of economic evaluations met the inclusion criteria of the research. The quality assessment showed that 20 articles had scores within the range of 75 to 100 (high quality), and 9 studies had scores within the range of 50 to 74 (moderate quality). All of the identified studies had been carried out based on modelling, and 23 studies used decision trees to model acute events after surgery. In addition, 20 studies utilized a Markov model to capture long-term complications of VTE. The results showed that rivaroxaban was more cost-effective than apixaban and dabigatran from a perspective of the health care system in the prevention of VTE after total knee and total hip replacement surgery. In addition, apixaban was associated with a lower risk for bleeding events than other NOACs, making it the most cost-effective NOAC from the perspective of the payer.

IMPLICATIONS

The results suggest that NOACs are cost-effective alternatives to low-molecular-weight heparins. Rivaroxaban and dabigatran were assessed as the most and least cost-effective prophylaxis options, respectively, after joint replacement surgery for the prevention of VTE. It is recommended that future research be conducted on economic evaluations of edoxaban.

Systematic review of prophylaxis for venous thromboembolism after knee arthroplasty: enoxaparin versus rivaroxaban

Total knee arthroplasty is an elective procedure performed on relatively healthy individuals. However, due to the inherent risk of venous thromboembolism, drugs are used for its prophylaxis. The objective of the present study was to conduct a systematic review of the literature to compare the efficacy of enoxaparin and rivaroxaban in preventing this complication and the risk of intraoperative bleeding. We reviewed the SciELO, Pubmed and Cochrane databases with the descriptors knee arthroplasty, rivaroxaban and enoxaparin through the PICO search strategy. Inclusion criteria were the articles during the study period comparing both drugs in knee arthroplasty. Relevant criteria to study eligibility were articles published since 2010 and with a sample of more than 20 patients; studies obtained in their entirety; and studies with follow-up of more than 12 months. The variables used to compare the articles were the most common postoperative complications of knee arthroplasties: venous thromboembolism and bleeding. We used the Review Man software, version 5.3, for structuring the review. In the studies analyzed, considering symptomatic venous thromboembolism, rivaroxaban resulted in higher benefits when compared to enoxaparin.

Rivaroxaban versus enoxaparin for the prevention of venous thromboembolism after total knee arthroplasty: A meta-analysis

OBJECTIVE

This article analyzed the clinical efficacy and tolerability of rivaroxaban and enoxaparin in patients undergoing total knee arthroplasty (TKA) surgery.

METHODS

Five randomized, controlled clinical trials on rivaroxaban versus enoxaparin in patients who underwent TKA were identified and included in this meta-analysis.

RESULTS

The meta-analysis indicated that rivaroxaban prophylaxis was associated with lower rates of symptomatic venous thromboembolism (VTE) (relative risk[RR]:0.55; 95% confidence interval [CI]: 0.35-0.86; P = .009), symptomatic deep vein thrombosis (DVT) (RR 0.44, 95% CI 0.25-0.80, P = .007), asymptomatic DVT (RR: 0.57; 95% CI: 0.37-0.89; P = .01), distal DVT (RR: 0.62; 95% CI: 0.45-0.85; P = .003) and proximal DVT (RR: 0.42; 95% CI: 0.24-0.75; P = .004). Compared with the enoxaparin group, the incidence of symptomatic pulmonary embolism (PE) (RR: 0.48; 95% CI: 0.19-1.24; P = .13) in the rivaroxaban group was not significantly different. A nonsignificant trend towards all-cause death (RR: 0.38; 95% CI: 0.03-4.92; P = .46) or major bleeding (RR: 1.59; 95% CI: 0.77-3.27; P = .21) risk between rivaroxaban and enoxaparin prophylaxis was found.

CONCLUSION

Compared with the enoxaparin group, the group using rivaroxaban after TKA had a significantly lower rate of symptomatic VTE, symptomatic DVT, asymptomatic DVT, distal DVT, and proximal DVT. Our study shows that rivaroxaban after TKA is more effective than enoxaparin and did not increase major bleeding or all-cause mortality.

Cost-Effectiveness Analysis of Rivaroxaban for Treatment of Deep Vein Thrombosis and Pulmonary Embolism in Greece

BACKGROUND AND OBJECTIVE

Venous thromboembolism (VTE), comprising deep-vein thrombosis (DVT) and pulmonary embolism (PE), is a major healthcare concern that results in substantial morbidity and mortality with great economic burden for healthcare systems. Hence, the need for effective and efficient treatment of patients with VTE is important for both clinical and economic reasons. The objective of this study was to evaluate the cost effectiveness of rivaroxaban compared to standard of care (SoC) with enoxaparin followed by dose-adjusted vitamin-K antagonists for the treatment of DVT and PE in Greece.

METHODS

An existing Markov model was locally adapted from a third-party payer perspective to reflect the management and complications of DVT and PE in the course of 3-month cycles, up to death. The clinical inputs and utility values were extracted from published studies. Direct medical costs, obtained from local resources, were incorporated in the model and refer to year 2017. Both costs and outcomes were discounted at 3.5%. The incremental cost-effectiveness ratio (ICER) per quality-adjusted life year (QALY) gained was calculated. Probabilistic sensitivity analysis (PSA) was carried out to deal with uncertainty.

RESULTS

The base-case analysis showed that rivaroxaban in 3- and 6-month treatment duration for DVT and PE, respectively, as this is the common clinical practice in Greece, was associated with a 0.02 and 0.01 increment in QALYs compared to SoC, respectively. Rivaroxaban was associated with a reduced total cost in DVT (€85) but with an additional total cost in PE (€2) compared to SoC. Therefore, rivaroxaban was a dominant (less costly, more effective) and cost-effective (ICER: €177) alternative over SoC for the management of DVT and PE, respectively. PSA revealed that the probability of rivaroxaban being cost effective at a threshold of €34,000 per QALY gained was 99% and 81% for DVT and PE, respectively.

CONCLUSION

Rivaroxaban may represent a cost-effective option relative to SoC for the management of DVT and PE in Greece.

Economic Evaluations of New Oral Anticoagulants for the Prevention of Venous Thromboembolism After Total Hip or Knee Replacement: A Systematic Review

BACKGROUND

Total hip replacement (THR) and total knee replacement (TKR) surgeries are being performed with increasing regularity and are associated with a high risk of developing a venous thromboembolism (VTE). New oral anticoagulants (NOACs) may be more effective at preventing VTEs but are associated with more bleeding events versus traditional anticoagulants.

OBJECTIVE

The objective of this systematic review was to identify published economic analyses of NOACs for primary VTE prophylaxis following THR and TKR surgeries, and to summarise the modelling techniques used and the cost-effectiveness results.

METHODS

Electronic searches of MEDLINE, EconLit and The Cochrane Library were performed from January 2008 to February 2015. Reference lists of included articles and reviews were examined for relevant studies.

RESULTS

Sixteen relevant economic analyses were identified, all of which used decision-tree structures to model acute events after surgery; 13 included a chronic-phase Markov module to capture long-term complications of VTE and recurrent VTE events. All studies included prophylaxis-related major bleeding events and captured both symptomatic and asymptomatic VTE-related events; nine studies distinguished between distal and proximal deep vein thrombosis events. Overall, rivaroxaban dominated enoxaparin in eight of 11 studies and dalteparin in one study, dabigatran dominated enoxaparin in five of seven studies and apixaban dominated enoxaparin in two of two studies. Rivaroxaban dominated dabigatran in four of four studies, apixaban dominated dabigatran in two of two studies and rivaroxaban dominated apixaban in one study.

CONCLUSIONS

The economic analyses showed reasonable consistency in the model structures used and the events captured. The results strongly suggested that NOACs are cost effective alternatives to low molecular-weight heparin. Dabigatran appeared to be the least cost effective NOAC. More research is needed to assess the cost effectiveness of apixaban and edoxaban.

Rivaroxaban: an oral factor Xa inhibitor

BACKGROUND

Currently available anticoagulants utilized for venous thromboembolism (VTE) treatment and prevention and stroke prevention in patients with atrial fibrillation (AF) have proven effectiveness but are not optimally utilized because of barriers such as the need for subcutaneous administration and requisite routine laboratory monitoring. Rivaroxaban, a novel oral Xa inhibitor, is an alternative to standard therapies utilized for VTE prevention after elective orthopedic surgery, primary and secondary stroke prevention in nonvalvular AF, VTE treatment after an acute VTE event, and secondary prevention after the acute coronary syndromes (ACS).

OBJECTIVE

This article reviews the pharmacology, efficacy, and tolerability of rivaroxaban for VTE prophylaxis in post-orthopedic surgery and medically ill patients, stroke prevention in nonvalvular AF, adjunctive therapy in patients with ACS, and VTE treatment.

METHODS

International Pharmaceutical Abstracts and EMBASE were searched for English-only clinical trials and reviews published between 1970 and March 15, 2012. PubMed was searched for articles published between 1970 and June 30, 2012. Additional trials and reviews were identified from the citations of published articles.

RESULTS

Eighty-nine publications were identified: 10 clinical trials and 1 meta-analysis were used to obtain efficacy and tolerability data, and 1 analysis of pooled data from the clinical trials was included; 17 pharmacokinetic, pharmacodynamic, and drug-drug interaction studies were included; and 5 cost-analyses were reviewed. These data showed rivaroxaban to be noninferior to enoxaparin for thromboprophylaxis of VTE after total knee and total hip replacement surgery. It was also shown to be noninferior to vitamin K antagonist therapy for primary and recurrent stroke prevention in nonvalvular AF as well as for the treatment of VTE after an acute deep vein thrombosis or pulmonary embolism. It also showed benefit in lowering the risk for major adverse cardiovascular events after ACS. Differences in major bleeding rates were not statistically significant between rivaroxaban and comparators across the various studies, with the exception of ACS, in which there were higher rates of non-coronary artery bypass graft surgery related bleeding and intracranial hemorrhage.

CONCLUSIONS

Based on the findings of the studies reported in this review, rivaroxaban is an effective option for the prevention of VTE after orthopedic surgery, stroke prevention for nonvalvular AF, and treatment of VTE. At this time, rivaroxaban cannot be recommended for secondary risk reduction after ACS because of the increased bleeding risk.

Venous thromboembolism: annualised United States models for total, hospital-acquired and preventable costs utilising long-term attack rates

Healthcare reform is upon the United States (US) healthcare system. Prioritisation of preventative efforts will guide necessary transitions within the US healthcare system. While annual deep-vein thrombosis (DVT) costs have recently been defined at the US national level, annual pulmonary embolism (PE) and venous thromboembolism (VTE) costs have not yet been defined. A decision tree and cost model were developed to estimate US health care costs for total PE, total hospital-acquired PE, and total hospital-acquired "preventable" PE. The previously published DVT cost model was modified, updated and combined with the PE cost model to elucidate the same three categories of costs for VTE. Direct and indirect costs were also delineated. For VTE in the base model, annual cost ranges in 2011 US dollars for total, hospital- acquired, and hospital-acquired "preventable" costs and were $13.5-$27.2, $9.0-$18.2, and $4.5-$14.2 billion, respectively. The first sensitivity analysis, with higher incidence rates and costs, demonstrated annual US total, hospital-acquired, and hospital-acquired "preventable" VTE costs ranging from $32.1-$69.3, $23.7-$51.5, and $11.9-$39.3 billion, respectively. The second sensitivity analysis with long-term attack rates (LTAR) for recurrent events and post-thrombotic syndrome and chronic pulmonary thromboembolic hypertension demonstrated annual US total, hospital-acquired, and hospital-acquired "preventable" VTE costs ranging from $15.4-$34.4, $10.3-$25.4, and $5.1-$19.1 billion, respectively. PE costs comprised a majority of the VTE costs. Prioritisation of effective VTE preventative strategies will reduce significant costs, morbidity and mortality within the US healthcare system. The cost models may be utilised to estimate other countries' costs or VTE-specific disease states.