Cost effectiveness of tinzaparin sodium versus unfractionated heparin in the treatment of proximal deep vein thrombosis

Low-molecular-weight heparins for the prevention of recurrent venous thromboembolism in patients with cancer: A systematic literature review of efficacy and cost-effectiveness

Background

Patients with cancer have an elevated risk of venous thromboembolism. Importantly, patients with cancer, who have metastatic disease, renal insufficiency, or are receiving anticancer therapy, have an even higher risk of a recurrent event. Similarly, the risk of recurrent venous thromboembolism is higher than the risk of an initial event. To reduce the risk, extended duration of prophylaxis for up to six months with low-molecular-weight heparins such as dalteparin, enoxaparin, nadroparin, and tinzaparin is recommended by international guidelines. In this paper, the clinical and economic literature is reviewed to provide evidenced based recommendations based on clinical benefit and economic value.

Methods

A systematic review of major databases was conducted from January 1996 to October 2016 for randomized controlled trials evaluating the four distinct low-molecular-weight heparins against a vitamin K antagonists control group for the prevention of recurrent venous thromboembolism in patients with active cancer. This was then followed by the application of the National Institute of Health and Clinical Excellence guidance to assess the quality of all trials that met the inclusion criteria. Finally, the cost-effectiveness literature supporting the value proposition of each product was reviewed.

Results

Six randomized trials met the inclusion criteria. There were one, two, and three trials that compared dalteparin, tinzaparin, and enoxaparin to a vitamin K antagonists control group. However, there were no trials for nadroparin in the setting of secondary venous thromboembolism prevention. In addition, only the dalteparin and one of the tinzaparin trials were of high quality and adequately powered. Of the two studies, only the dalteparin trial reported a statistically significant benefit in terms of venous thromboembolism absolute risk reduction when compared to a vitamin K antagonists control group (HR = 0.48; p = 0.002). In addition, there was robust pharmacoeconomic data from Canada, the Netherlands, France, and Austria supporting the cost-effectiveness of dalteparin for this indication. There were no such studies for any of the other agents.

Conclusions

The totality of high-quality clinical and cost-effectiveness data supports the use of dalteparin over other low-molecular-weight heparins for preventing recurrent venous thromboembolism in patients with cancer.

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.

Economic evaluation of using a genetic test to direct breast cancer chemoprevention in white women with a previous breast biopsy

BACKGROUND

Tamoxifen therapy reduces the risk of breast cancer but increases the risk of serious adverse events including endometrial cancer and thromboembolic events.

OBJECTIVES

The cost effectiveness of using a commercially available breast cancer risk assessment test (BREVAGen™) to inform the decision of which women should undergo chemoprevention by tamoxifen was modeled in a simulated population of women who had undergone biopsies but had no diagnosis of cancer.

METHODS

A continuous time, discrete event, mathematical model was used to simulate a population of white women aged 40-69 years, who were at elevated risk for breast cancer because of a history of benign breast biopsy. Women were assessed for clinical risk of breast cancer using the Gail model and for genetic risk using a panel of seven common single nucleotide polymorphisms. We evaluated the cost effectiveness of using genetic risk together with clinical risk, instead of clinical risk alone, to determine eligibility for 5 years of tamoxifen therapy. In addition to breast cancer, the simulation included health states of endometrial cancer, pulmonary embolism, deep-vein thrombosis, stroke, and cataract. Estimates of costs in 2012 US dollars were based on Medicare reimbursement rates reported in the literature and utilities for modeled health states were calculated as an average of utilities reported in the literature. A 50-year time horizon was used to observe lifetime effects including survival benefits.

RESULTS

For those women at intermediate risk of developing breast cancer (1.2-1.66 % 5-year risk), the incremental cost-effectiveness ratio for the combined genetic and clinical risk assessment strategy over the clinical risk assessment-only strategy was US$47,000, US$44,000, and US$65,000 per quality-adjusted life-year gained, for women aged 40-49, 50-59, and 60-69 years, respectively (assuming a price of US$945 for genetic testing). Results were sensitive to assumptions about patient adherence, utility of life while taking tamoxifen, and cost of genetic testing.

CONCLUSIONS

From the US payer's perspective, the combined genetic and clinical risk assessment strategy may be a moderately cost-effective alternative to using clinical risk alone to guide chemoprevention recommendations for women at intermediate risk of developing breast cancer.

International recommendations for the prevention and treatment of venous thromboembolism associated with cancer

Venous thromboembolism (VTE) is a common complication and a leading cause of death in oncological patients. Recent guidelines have been established for the treatment and prevention of VTE in oncological patients in various clinical situations. These guidelines recommend: (a) prophylactic anticoagulation in all hospitalized oncological patients in whom there are no contraindications; (b) prophylactic anticoagulation in patients scheduled for major oncological surgery in whom there are no contraindications; (c) prolonged (>or=6 months) anticoagulant therapy in oncological patients with manifest VTE in order to prevent a new episode; (d) no routine prophylactic anticoagulation in ambulatory patients without VTE receiving chemotherapy, except when they are receiving treatment with anti-cancer agents with a high risk of thrombogenicity, such as thalidomide- or lenalidomide-based chemotherapeutic regimens; and (e) no use of prophylactic anticoagulants to improve survival in patients with cancer without manifest VTE. Although vitamin K antagonists, unfractionated heparin and in some cases fondaparinux sodium could be used for the treatment of VTE, low molecular weight heparins are recommended for initial and continuous anticoagulant treatment in oncological patients with VTE, as well as for its prevention.

Hospital-based costs associated with venous thromboembolism treatment regimens

INTRODUCTION

Venous thromboembolism (VTE) poses a significant health and economic burden in US hospitals. Clinical guidelines for acute VTE treatment recommend antithrombotic therapy (at least 5 days) with low molecular weight heparin (LMWH) or unfractionated heparin (UFH). With upcoming US national performance measures requiring successful implementation of evidence-based therapy, cost considerations for anticoagulant choice are of increasing importance to hospitals.

METHODS

This retrospective cohort analysis utilizes discharge records from a large real-world US population (January 2002 to December 2006) to provide total, direct, inpatient medical costs associated with LMWH and UFH for acute VTE treatment. Furthermore, for both LMWH and UFH discharges, we compare VTE-related readmission rates at 30 and 90 days after discharge.

RESULTS

In total, 57 131 discharges were identified (57.7% LMWH; 42.3% UFH). After adjustment for covariates, including age, severity of illness, and length of stay, total direct medical costs per hospital discharge for UFH were $3476.22 vs. $3056.42 for LMWH (P < 0.0001; difference $420). Costs were significantly higher in the UFH group for most cost categories. Notably, drug acquisition cost was higher for LMWH. LMWH treatment was 12% [odds ratio (OR) 0.876; P < 0.001] and 10% (OR 0.895; P = 0.0006) less likely to result in VTE readmission within 30 and 90 days, respectively.

CONCLUSIONS

This study provides the first large, real-world analysis of the total direct medical costs of treating VTE in-hospital. It confirms that, despite higher drug acquisition costs, LMWH is cost-saving compared with UFH in the inpatient setting, and is associated with a lower VTE readmission rate at 30 and 90 days than is UFH.

Trends in cost effectiveness analyses in orthopaedic surgery

Worldwide, programs dealing with musculoskeletal health are required to set priorities and allocate resources within the constraint of limited funding. There is increasing pressure for medical technology assessment, which traditionally has involved evaluating safety and effectiveness, to also include consideration of cost effectiveness. We updated our database of orthopaedic cost-effectiveness studies, critically reviewed their methods, and examined trends over time. Current analyses have numerous shortcomings, such as the inclusion of relatively few studies, inconsistent methodologic approaches, and lack of transparency. The wide variation in cost-effectiveness ratios observed among current interventions suggests efficiency can be improved. Despite reimbursement authorities in many other countries formally considering cost-effectiveness when determining coverage of new technologies, Medicare has been resistant to considering costs of treatments. Regardless of this policy deficiency, conducting cost-effectiveness analyses represents a prudent step forward in illuminating the tradeoffs involved in difficult resource allocation decisions, and there is an urgent need to consider economic impact in future studies using standardized and transparent methods.

Pharmacoeconomic considerations in anticoagulant drug use

Anticoagulants are used for the prevention and treatment of venous thromboembolism and for the secondary prevention of stroke and myocardial infarction. The list of available anticoagulants includes unfractionated heparin, low molecular weight heparins, fondaparinux, warfarin and the direct thrombin inhibitors. Numerous randomised controlled trials have pitted one anticoagulant against another to ascertain superiority in terms of safety and efficacy. Differences in these outcomes are assessed using appropriate statistical tests. When a statistically significant difference is found, it is generally accepted that one option is superior to another. There is also an interest in whether there is a clinically significant difference between two or more treatments, even when there may not be a statistically significant difference. This decision is reached through clinical judgment based on logical and ethical considerations. Another important way to judge the difference between alternative treatment strategies is to test for economically significant differences. This is accomplished through pharmacoeconomic analysis. This paper reviews the evidence gathered from published studies designed to detect an economically significant difference between two or more anticoagulants used for the same clinical indication.

A study on the safety, efficacy, and efficiency of sulodexide compared with acenocoumarol in secondary prophylaxis in patients with deep venous thrombosis

This study was carried out to study the safety and efficacy of a fixed dosage of sulodexide compared to adjusted dosages (INR) of acenocoumarol as secondary prophylaxis in patients with deep vein thrombosis (DVT) in lower limbs. An economic evaluation based on the criteria of use in normal clinical practice was also performed. One hundred and fifty patients of both sexes were included, all over 18 years of age and diagnosed with proximal DVT of the lower limbs by color echo-Doppler, and with clinical evolution of less than 1 month. The patients were initially treated with low-molecular-weight heparin (LMWH) and urokinase in accordance with the established protocol. They were then randomized to continue treatment with acenocoumarol and INR adjustments every 30 days, or with sulodexide. Treatment was extended for 3 months with monthly follow-up visits and a final visit at 3 months posttreatment. No differences between the groups were detected concerning demographic or basal characteristics in clinical evolution or adverse reactions. In the group treated with sulodexide, no major/minor hemorrhagic complications were detected. On the other hand, in the acenocoumarol group, 1 major hemorrhage and 9 minor hemorrhages were produced (13.3%), reaching statistical difference in relation to the sulodexide group (p = 0.014; CI from 95% of 4.7% to 19.4%). Regarding the economic impact, treatment costs with sulodexide are much less than those with acenocoumarol, the data confirmed by the sensitivity analyses performed. The results prove the efficacy, safety, and efficiency of sulodexide as a secondary prophylaxis in thromboembolic disease, avoiding hemorrhagic risks and the monitoring of patients, and providing significant savings to the health system.

Cost effectiveness of bemiparin sodium versus unfractionated heparin and oral anticoagulants in the acute and long-term treatment of deep vein thrombosis

INTRODUCTION

Low-molecular-weight heparins (LMWHs) are at least as effective and well tolerated as unfractionated heparin (UFH) in the treatment of deep vein thrombosis (DVT), offering easier administration and obviating the need for anticoagulant monitoring, but have a higher acquisition cost than UFH.

OBJECTIVE

To quantify the potential economic impact of two regimens of subcutaneous bemiparin 115 IU/kg/day for 7-10 days (plus oral anticoagulants [OAC] or followed by long-term bemiparin 3500IU) versus dose-adjusted intravenous UFH for 7 days plus OAC for 3 months in the acute and long-term treatment of DVT. The representative patient was a 62-year-old, 77 kg male with proximal DVT of the lower limbs.

METHODS

A cost-effectiveness analysis was performed using a decision-tree modelling approach. The results were expressed in terms of costs (euro, 2002 values) and incremental cost effectiveness. The treatment costs (hospital stay, physician services, drug administration) and costs incurred due to complications (pulmonary embolism, recurrent DVT, bleeding events, thrombocytopenia and deaths) during the 3-month study period were considered for the primary analysis. Life expectancy and QALYs were considered for the secondary analysis. The study was performed in the setting of the Spanish National Health System.

RESULTS

Bemiparin plus OAC or long-term bemiparin for 3 months provided net cost savings of euro 769 and euro 908 per patient, respectively, compared with UFH plus OAC (UFH plus OAC euro 4128 vs bemiparin plus OAC euro 3359 vs long-term bemiparin euro 3220). Bemiparin plus OAC and long-term bemiparin for 3 months were calculated to avoid 27 and 7 additional VTE events, respectively, per 1000 patients treated. Bemiparin plus OAC or long-term bemiparin increased quality-adjusted life expectancy by approximately 1.72 and 0.74 years, respectively, compared with UFH plus OAC. The univariate sensitivity analysis supported the cost effectiveness of bemiparin in all the ranges tested for complications and costs.

CONCLUSIONS

Our model suggests that bemiparin plus OAC or long-term bemiparin for 3 months may be dominant strategies over UFH plus OAC in the treatment of DVT from the Spanish National Health System perspective, offering better outcomes and cost savings. Long-term bemiparin may be a cost-neutral alternative to bemiparin plus OAC.

Implementation of outpatient treatment of deep-vein thrombosis in private practices in Germany

OBJECTIVE

Implementation of outpatient treatment (OT) of deep-vein thrombosis (DVT) is slow despite clear evidence that it is effective, safe and cost-efficient.

DESIGN AND METHOD

An initiative was launched with the help of the Professional Association of Phlebologists of Germany and the industry to familiarize physicians in private practice who had no prior experience with OT of DVT. Data on quality of treatment with the low-molecular-weight heparin tinzaparin and phenprocoumon, compliance, clinical outcome, venous ultrasound, patients' satisfaction and quality of life were collected in a registry, which was open from July 1999 to December 2000. The results were published and their impact on further management of patients was assessed in second survey reported here. Patients of both series were followed-up clinically and with ultrasound over the 1st month of treatment.

RESULTS

Of 67 physicians entering 827 patients into the registry 26 answered a questionnaire on how they treated further patients. Their case load had increased by 450% and data were provided on 540 consecutive patients managed between January and June 2002. OT increased overall from 76 to 92%, that of popliteo-femoral DVT from 71 to 92%, and that of pelvic DVT from 38 to 65%. Medical reasons to decide against OT decreased from 89 to 56% (p<.01). Immediate leg compression was changed from bandaging to medical compression stockings in 20 of the 26 centres (p<.05). In total, data were gathered from OT of 1124 patients. No secondary hospitalisations were required and only one patient had a documented progression of the DVT.

CONCLUSIONS

OT was successfully implemented in private practices through the initiative of individual physicians with support of the professional association and sponsoring by the industry-to the benefit of the providers but as much of the patients and their cost bearers.

Tinzaparin in the treatment of venous thromboembolism

Low molecular weight heparin (LMWH) has been widely used for the initial treatment of patients presenting with venous thromboembolism. The LMWH, tinzaparin, has been shown in randomised clinical trials to be as effective and safe as unfractionated heparin for the initial treatment of venous thromboembolism and in clinical trials, it has been used in place of warfarin for the long-term treatment of deep vein thrombosis. Tinzaparin can safely be given to patients with significant renal impairment (creatinine clearance of > or = 20 ml/min) and the dose of tinzaparin does not need to be altered in patients with a body mass index of > 25.

Tinzaparin sodium: a review of its pharmacology and clinical use in the prophylaxis and treatment of thromboembolic disease

Tinzaparin sodium (tinzaparin; innohep) is a low molecular weight heparin (LMWH) formed by the enzymatic degradation of porcine unfractionated heparin (UFH). In clinical trials, once-daily subcutaneous (SC) tinzaparin was effective and generally well tolerated in the prophylaxis and treatment of thromboembolic disease. SC tinzaparin 75 anti-Xa IU/kg/day showed similar thromboprophylactic efficacy to adjusted-dosage oral warfarin in patients undergoing total hip arthroplasty; in patients undergoing knee replacement, the incidence of deep vein thrombosis (DVT) was significantly lower with tinzaparin. The drug had similar efficacy to equivalent-dosage SC enoxaparin sodium in orthopaedic surgery. In patients undergoing general surgery, SC tinzaparin 3500 anti-Xa IU/day was of equivalent thromboprophylactic efficacy to SC UFH 5000IU twice daily. Encouraging preliminary results have been obtained with tinzaparin in the prevention of DVT in patients with complete motor paralysis. In the initial treatment of acute proximal DVT and pulmonary embolism, SC tinzaparin 175 anti-Xa IU/kg/day was at least as effective as adjusted-dosage intravenous (IV) UFH. In the outpatient treatment of venous thromboembolism, tinzaparin has demonstrated similar efficacy to dalteparin sodium (dalteparin) and warfarin. Tinzaparin was effective in preventing clotting in haemodialysis circuits; the anticoagulant efficacy of tinzaparin in patients undergoing haemodialysis was similar to that of SC dalteparin and similar to or less than (although in this case the tinzaparin dose was too low for sufficient anticoagulant efficacy) that of IV UFH. Advantages of tinzaparin over UFH and warfarin include ease of administration and lack of need for laboratory monitoring. Tinzaparin is more cost effective than UFH in the treatment of established thromboembolic disease, and home-based treatment with tinzaparin may offer greater cost benefits than hospital-based therapy. Tinzaparin is well tolerated, including in elderly patients and those with renal impairment receiving long-term treatment. Incidences of major bleeding complications were low and reports of heparin-induced thrombocytopenia were infrequent in clinical studies. In conclusion, tinzaparin is a valuable LMWH in the prophylaxis and management of thromboembolic disease.

A systematic review of economic analyses of low-molecular-weight heparin for the treatment of venous thromboembolism

INTRODUCTION

Public concerns about the increase in health care expenditure have prompted investigators to analyze the costs and benefits of health care interventions. We conducted a systematic review of economic analyses of venous thromboembolism treatment focusing on studies evaluating low-molecular-weight heparin.

MATERIALS AND METHODS

We identified studies by a MEDLINE search and a review of bibliographies of retrieved articles. From each eligible study, we extracted data on the study characteristics, the effectiveness, and the cost of managing the venous thromboembolism with respect to treatment. We critically appraised the studies according to the framework from the Users' Guides to the Medical Literature XIII: How to Use an Article on Economic Analysis of Clinical Practice.

RESULTS

Six of these eight economic analyses of venous thromboembolism treatment that met the inclusion criteria for this review showed that low-molecular-weight heparin is associated with less recurrent venous thromboembolism and is less costly than treatment with unfractionated heparin. Although discrete recurrent venous thromboembolism event rates were not included in the seventh study, these investigators concluded that the cost of low-molecular-weight heparin for the treatment of venous thromboembolism treatment was offset by the savings associated with fewer hospital admissions when low-molecular-weight heparin was used. In the eighth study, although the cost of treatment with low-molecular-weight heparin was higher than treatment with unfractionated heparin, the investigators concluded that low-molecular-weight heparin is cost-effective for inpatient management.

CONCLUSIONS

Low-molecular-weight heparin treatment may confer economic advantages over unfractionated heparin therapy because it does not require anticoagulant monitoring and it facilitates outpatient therapy.

Tinzaparin: considerations for use in clinical practice

OBJECTIVE

To evaluate the safety and effectiveness of tinzaparin for the prevention and treatment of venous thromboembolism (VTE).

DATA SOURCES

A MEDLINE and PubMed database search (1980-December 2002) was conducted. Only articles written in English were reviewed.

STUDY SELECTION AND DATA EXTRACTION

Articles reporting the safety, efficacy, and cost-effectiveness of tinzaparin in humans were evaluated. Emphasis was placed on randomized, controlled trials.

DATA SYNTHESIS

Tinzaparin sodium is a low-molecular-weight heparin (LMWH) that exerts its anticoagulant effect through inhibition of factors Xa and IIa and release of tissue factor pathway inhibitor from the vascular epithelium. Tinzaparin is indicated for treatment of acute symptomatic deep-vein thrombosis (DVT), with or without pulmonary embolism. Clinical studies suggest that tinzaparin is also effective for VTE prophylaxis, as well as other indications. Once-daily subcutaneous tinzaparin is equally or more effective than intravenous unfractionated heparin (UFH) for prevention and treatment of VTE, at least as safe as UFH for bleeding complications, and requires little or no monitoring. No dose "cap" is required for obese patients, and no initial dosing adjustments are necessary in elderly and/or renally impaired patients, although some monitoring is recommended. The few comparative data available suggest that tinzaparin efficacy may be comparable to that of other LMWHs; more comparative studies are needed. Pharmacoeconomic studies indicate a favorable cost-benefit ratio.

CONCLUSIONS

Tinzaparin is safe and effective for prevention and treatment of DVT. Consistent once-daily dosing may facilitate self-administration of tinzaparin in the outpatient setting.