BUSINESS
Comparing Medical Cost of Care for Patients with Metastatic Breast Cancer Receiving Taxane Therapy: Claims Analysis Rex W. Force, PharmD; Brooke A. Pugmire, PharmD; Vaughn L. Culbertson, PharmD Stakeholder Perspective, page 284
Background: It has been estimated that more than $8 billion is spent annually on the management of breast cancer in the United States. The taxane chemotherapeutic agents are cornerstones in the treatment of breast cancer, yet no study has assessed whether the choice of a taxane affects the economic outcomes of metastatic breast cancer treatment. Objective: To determine if differences exist in the medical cost of care in patients receiving taxane-based chemotherapy for metastatic breast cancer, and to compare the use of ancillary medications (for neutropenia, anemia, and nausea and vomiting) and their associated costs among taxanes. Method: We identified women with metastatic breast cancer based on diagnosis codes and the women’s previous adjuvant chemotherapeutic regimens. Paid medical insurance claims were captured for the 24-month study period, from January 1, 2006, through December 31, 2007. The groups were determined according to the specific taxane administered. Total medical costs were captured from the date of first taxane administration to the end of data availability. Outpatient pharmacy costs were not available. A multivariate analysis was used to evaluate the total medical costs in each group. Median total medical costs per patient per month during the study period were adjusted using a multiple regression analysis. Utilization and cost of medications administered in the office or hospital for chemotherapy-induced adverse effects were captured and adjusted with Tobit models. Results: Of the 2245 study participants, 1035 received docetaxel, 997 received generic paclitaxel, and 213 received nab-paclitaxel. On average, patients in the nab-paclitaxel group received more doses (9.6) than those in the generic paclitaxel (6.0) or docetaxel (4.8) groups. The multivariate analysis was robust, explaining 72% of the variability in total medical costs across the 3 taxane groups. Median per-patient per-month total medical costs for study participants were within approximately $800 of each other among the groups. Generic paclitaxel had the lowest total medical costs. The total costs for docetaxel and nab-paclitaxel were not significantly different. Nab-paclitaxel had the lowest utilization and lowest costs associated with colony-stimulating factors. The proportion of patients receiving erythropoiesis-stimulating agents was not significantly different among the 3 drugs, but the costs for these agents were significantly lower in patients receiving nab-paclitaxel than in those receiving docetaxel. Antiemetic use was highest in the docetaxel group, but the costs for antiemetics were not different among the 3 taxane groups. Conclusion: The differences in total medical costs among the 3 taxanes were modest. Total medical costs were lowest for patients receiving generic paclitaxel and comparable between the docetaxel and nab-paclitaxel groups. Patients taking nab-paclitaxel received more doses than patients taking the other taxanes. Nab-paclitaxel was associated with lower utilization and costs for colony-stimulating factors compared with generic paclitaxel and docetaxel.
Rex W. Force
Am Health Drug Benefits. 2010;3(4):276-284. www.AHDBonline.com Disclosures are at end of text
Dr Force is Professor and Director of Research, Family Medicine and Pharmacy Practice, Idaho State University, and Partner, improveRX, LLC; Dr Pugmire is Clinical Assistant Professor, Pharmacy Practice, Idaho State University, and Clinical Project Manager, improveRX; Dr Culbertson is Professor, Pharmacy Practice, Idaho State University, and Partner, improveRX; all at Pocatello, ID.
276
American Health & Drug Benefits
l
www.AHDBonline.com
July/August 2010
l
Vol 3, No 4
Comparing Medical Cost of Care for MBC
B
reast cancer is the most frequently diagnosed cancer in US women, and ranks second among cancer-related deaths in women, after lung cancer.1 It is estimated that $8.1 billion (in 2004 $US) in total healthcare costs are spent annually on breast cancer diagnosis and treatment in the United States.2 Chemotherapeutic agents represent a significant portion of the cost of breast cancer treatment, and health plans are managing these costs with care pathways and other utilization management strategies.
The Taxanes Taxanes are among the most frequently used forms of systemic therapy for the treatment of breast cancer.3 These chemotherapeutic agents can be prescribed alone or in combination with other systemic therapies or with local treatment, such as surgery and/or radiation. Taxanes are mitotic inhibitors originally isolated from the bark of the Pacific yew tree, Taxus brevifolia. Three taxanes are currently available in the United States, although this is an area of active drug development. The first of these agents to be marketed in the United States, paclitaxel injection (Taxol), was approved by the US Food and Drug Administration (FDA) in 1992 as an injectable formulation dissolved in a proprietary version of polyethoxylated castor oil called Cremophor EL and ethanol as a delivery agent.4 The second agent—docetaxel (Taxotere)—received FDA approval in 1996; docetaxel is a semisynthetic taxane dissolved in polysorbate 80 and 13% ethanol and water for injection.5 The toxicity of these 2 solvent-based taxanes includes bone marrow suppression (principally neutropenia), alopecia, and hypersensitivity reactions.6 Irizarry and colleagues reviewed 171 reported cases of anaphylaxis associated with the Cremophor EL–based paclitaxel. A total of 34% were fatal reactions, although the authors suggested that this adverse event (AE) is underreported.7 Although neurotoxicity and myalgias/ arthralgias have been cited as potential AEs with paclitaxel and docetaxel, these events are of greater clinical concern with paclitaxel—again, likely because of the Cremophor EL solvent.6 However, docetaxel has been associated with the development of significant fluid retention (eg, edema, ascites, pleural effusions), the incidence and severity of which appear to be reduced by premedication with corticosteroids.6 These toxicities may result in dose reductions, delays in continuation of treatment, or even discontinuation of chemotherapy. In an attempt to reduce the significant toxicity associated with the solvent-based taxanes, a new formulation of paclitaxel was developed—nab-paclitaxel (Abraxane)—in which the active drug is bound to albumin.8 Nab-paclitaxel received FDA approval in 2005.
Vol 3, No 4
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July/August 2010
KEY POINTS ➤
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Medication costs for oncology continue to increase dramatically. The treatment of metastatic breast cancer consists of several treatment modalities, including a taxane. Taxane use in metastatic breast cancer should be evaluated with cost of care analyses to account for differences in ancillary medication use, costs of complications, and other chemotherapeutic strategies. These factors contribute to total medical cost, which may be used as the primary outcome measure in a pharmacoeconomic evaluation rather than simply drug acquisition cost alone. This is the first study to evaluate the total cost of care for metastatic breast cancer from the perspective of taxane choice among the 3 available taxanes—generic paclitaxel, docetaxel, and nabpaclitaxel. Per-patient per-month medical costs for women receiving 1 of the 3 taxanes were within $800 of each other. As can be expected, generic paclitaxel was the least expensive. The overall costs of breast cancer management are related to the entire chemotherapeutic regimen, potential side effects, and costs of hospitalization. In this study, women receiving nab-paclitaxel had the lowest expenditures for colony-stimulating factors.
This albumin-bound paclitaxel has demonstrated superior efficacy over the solvent-based paclitaxel in the treatment of metastatic breast cancer (MBC), as well as a more favorable AE profile.9,10 Although the solvent-based taxanes—paclitaxel and docetaxel—have lower drug acquisition costs than nabpaclitaxel, nab-paclitaxel offers potential clinical advantages, such as better tumor responses with lower rates of severe neutropenia and infusion-related reactions.9,10 Systematic reviews have indicated that taxanes are among the most active regimens in MBC.11 However, differences in the toxicity and efficacy of the taxanes exist. Gradishar and colleagues found that nab-paclitaxel was associated with better response rates compared with the solvent-based generic paclitaxel in MBC (33% vs 19%, respectively; P = .001), with a longer time to tumor progression (23.0 weeks vs 16.9 weeks, respectively; P = .006).10 In addition, the rates of severe neutropenia were significantly lower in the nab-paclitaxel group (9% vs 22%, respectively; P
Comparing Medical Cost of Care for Patients with Metastatic Breast Cancer Receiving Taxane Therapy: Claims Analysis Rex W. Force, PharmD; Brooke A. Pugmire, PharmD; Vaughn L. Culbertson, PharmD Stakeholder Perspective, page 284
Background: It has been estimated that more than $8 billion is spent annually on the management of breast cancer in the United States. The taxane chemotherapeutic agents are cornerstones in the treatment of breast cancer, yet no study has assessed whether the choice of a taxane affects the economic outcomes of metastatic breast cancer treatment. Objective: To determine if differences exist in the medical cost of care in patients receiving taxane-based chemotherapy for metastatic breast cancer, and to compare the use of ancillary medications (for neutropenia, anemia, and nausea and vomiting) and their associated costs among taxanes. Method: We identified women with metastatic breast cancer based on diagnosis codes and the women’s previous adjuvant chemotherapeutic regimens. Paid medical insurance claims were captured for the 24-month study period, from January 1, 2006, through December 31, 2007. The groups were determined according to the specific taxane administered. Total medical costs were captured from the date of first taxane administration to the end of data availability. Outpatient pharmacy costs were not available. A multivariate analysis was used to evaluate the total medical costs in each group. Median total medical costs per patient per month during the study period were adjusted using a multiple regression analysis. Utilization and cost of medications administered in the office or hospital for chemotherapy-induced adverse effects were captured and adjusted with Tobit models. Results: Of the 2245 study participants, 1035 received docetaxel, 997 received generic paclitaxel, and 213 received nab-paclitaxel. On average, patients in the nab-paclitaxel group received more doses (9.6) than those in the generic paclitaxel (6.0) or docetaxel (4.8) groups. The multivariate analysis was robust, explaining 72% of the variability in total medical costs across the 3 taxane groups. Median per-patient per-month total medical costs for study participants were within approximately $800 of each other among the groups. Generic paclitaxel had the lowest total medical costs. The total costs for docetaxel and nab-paclitaxel were not significantly different. Nab-paclitaxel had the lowest utilization and lowest costs associated with colony-stimulating factors. The proportion of patients receiving erythropoiesis-stimulating agents was not significantly different among the 3 drugs, but the costs for these agents were significantly lower in patients receiving nab-paclitaxel than in those receiving docetaxel. Antiemetic use was highest in the docetaxel group, but the costs for antiemetics were not different among the 3 taxane groups. Conclusion: The differences in total medical costs among the 3 taxanes were modest. Total medical costs were lowest for patients receiving generic paclitaxel and comparable between the docetaxel and nab-paclitaxel groups. Patients taking nab-paclitaxel received more doses than patients taking the other taxanes. Nab-paclitaxel was associated with lower utilization and costs for colony-stimulating factors compared with generic paclitaxel and docetaxel.
Rex W. Force
Am Health Drug Benefits. 2010;3(4):276-284. www.AHDBonline.com Disclosures are at end of text
Dr Force is Professor and Director of Research, Family Medicine and Pharmacy Practice, Idaho State University, and Partner, improveRX, LLC; Dr Pugmire is Clinical Assistant Professor, Pharmacy Practice, Idaho State University, and Clinical Project Manager, improveRX; Dr Culbertson is Professor, Pharmacy Practice, Idaho State University, and Partner, improveRX; all at Pocatello, ID.
276
American Health & Drug Benefits
l
www.AHDBonline.com
July/August 2010
l
Vol 3, No 4
Comparing Medical Cost of Care for MBC
B
reast cancer is the most frequently diagnosed cancer in US women, and ranks second among cancer-related deaths in women, after lung cancer.1 It is estimated that $8.1 billion (in 2004 $US) in total healthcare costs are spent annually on breast cancer diagnosis and treatment in the United States.2 Chemotherapeutic agents represent a significant portion of the cost of breast cancer treatment, and health plans are managing these costs with care pathways and other utilization management strategies.
The Taxanes Taxanes are among the most frequently used forms of systemic therapy for the treatment of breast cancer.3 These chemotherapeutic agents can be prescribed alone or in combination with other systemic therapies or with local treatment, such as surgery and/or radiation. Taxanes are mitotic inhibitors originally isolated from the bark of the Pacific yew tree, Taxus brevifolia. Three taxanes are currently available in the United States, although this is an area of active drug development. The first of these agents to be marketed in the United States, paclitaxel injection (Taxol), was approved by the US Food and Drug Administration (FDA) in 1992 as an injectable formulation dissolved in a proprietary version of polyethoxylated castor oil called Cremophor EL and ethanol as a delivery agent.4 The second agent—docetaxel (Taxotere)—received FDA approval in 1996; docetaxel is a semisynthetic taxane dissolved in polysorbate 80 and 13% ethanol and water for injection.5 The toxicity of these 2 solvent-based taxanes includes bone marrow suppression (principally neutropenia), alopecia, and hypersensitivity reactions.6 Irizarry and colleagues reviewed 171 reported cases of anaphylaxis associated with the Cremophor EL–based paclitaxel. A total of 34% were fatal reactions, although the authors suggested that this adverse event (AE) is underreported.7 Although neurotoxicity and myalgias/ arthralgias have been cited as potential AEs with paclitaxel and docetaxel, these events are of greater clinical concern with paclitaxel—again, likely because of the Cremophor EL solvent.6 However, docetaxel has been associated with the development of significant fluid retention (eg, edema, ascites, pleural effusions), the incidence and severity of which appear to be reduced by premedication with corticosteroids.6 These toxicities may result in dose reductions, delays in continuation of treatment, or even discontinuation of chemotherapy. In an attempt to reduce the significant toxicity associated with the solvent-based taxanes, a new formulation of paclitaxel was developed—nab-paclitaxel (Abraxane)—in which the active drug is bound to albumin.8 Nab-paclitaxel received FDA approval in 2005.
Vol 3, No 4
l
July/August 2010
KEY POINTS ➤
➤
➤
➤
➤
Medication costs for oncology continue to increase dramatically. The treatment of metastatic breast cancer consists of several treatment modalities, including a taxane. Taxane use in metastatic breast cancer should be evaluated with cost of care analyses to account for differences in ancillary medication use, costs of complications, and other chemotherapeutic strategies. These factors contribute to total medical cost, which may be used as the primary outcome measure in a pharmacoeconomic evaluation rather than simply drug acquisition cost alone. This is the first study to evaluate the total cost of care for metastatic breast cancer from the perspective of taxane choice among the 3 available taxanes—generic paclitaxel, docetaxel, and nabpaclitaxel. Per-patient per-month medical costs for women receiving 1 of the 3 taxanes were within $800 of each other. As can be expected, generic paclitaxel was the least expensive. The overall costs of breast cancer management are related to the entire chemotherapeutic regimen, potential side effects, and costs of hospitalization. In this study, women receiving nab-paclitaxel had the lowest expenditures for colony-stimulating factors.
This albumin-bound paclitaxel has demonstrated superior efficacy over the solvent-based paclitaxel in the treatment of metastatic breast cancer (MBC), as well as a more favorable AE profile.9,10 Although the solvent-based taxanes—paclitaxel and docetaxel—have lower drug acquisition costs than nabpaclitaxel, nab-paclitaxel offers potential clinical advantages, such as better tumor responses with lower rates of severe neutropenia and infusion-related reactions.9,10 Systematic reviews have indicated that taxanes are among the most active regimens in MBC.11 However, differences in the toxicity and efficacy of the taxanes exist. Gradishar and colleagues found that nab-paclitaxel was associated with better response rates compared with the solvent-based generic paclitaxel in MBC (33% vs 19%, respectively; P = .001), with a longer time to tumor progression (23.0 weeks vs 16.9 weeks, respectively; P = .006).10 In addition, the rates of severe neutropenia were significantly lower in the nab-paclitaxel group (9% vs 22%, respectively; P
