Are health states 'timeless'? A case study of an acute condition: post-chemotherapy nausea and vomiting

Cost-effectiveness of adding daratumumab or bortezomib to lenalidomide plus dexamethasone for newly diagnosed multiple myeloma

BACKGROUND: Multiple myeloma survival rates are steadily increasing due to availability of new drug classes used in combination with corticosteroids and chemotherapy. The latest treatments are daratumumab or bortezomib in combination therapy with lenalidomide and dexamethasone (Rd). Daratumumab, a CD38-targeted, human IgG1k monoclonal antibody, and bortezomib, a proteasome inhibitor, are both approved as regimens for transplant-ineligible relapsed/refractory multiple myeloma (RRMM). There have been cost-effectiveness analyses for daratumumab and bortezomib use in RRMM, but there are limited data regarding cost-effectiveness for daratumumab or bortezomib use in newly diagnosed multiple myeloma patients who are ineligible for stem cell transplantation. OBJECTIVE: To compare the cost-effectiveness of 3 separate regimens-(1) daratumumab, lenalidomide, and dexamethasone triple therapy (DRd); (2) bortezomib and lenalidomide plus dexamethasone triple therapy (VRd); and (3) lenalidomide plus dexamethasone (Rd)-in patients with multiple myeloma ineligible for autologous stem cell transplant. METHODS: A 2-state Markov model was developed using a US health system perspective and lifetime time horizon. Transition probabilities were calculated from the latest progression-free survival data reported in two phase 3 randomized controlled trials-MAIA and SWOG S0777-and extrapolated using a Weibull distribution based on the Hoyle Henley method. National data sources were used to obtain costs in 2019 US dollars, discounted by 3%. Health state utilities from available literature were applied to each health state. Utility decrements for adverse events were individualized in each choice branch with utility decrement weighted by the percentage of patients who experienced the adverse event in the MAIA and SWOG S0777 trials. We assumed a treatment would be cost-effective at a willingness to pay (WTP) of $150,000 per progression-free quality-adjusted life-year ($/PFQALY). One-way and probabilistic sensitivity analyses were conducted. RESULTS: Rd standard therapy had the lowest overall cost at $329,867, followed by VRd at $385,434 and DRd with the highest overall total cost at $626,900. Rd was estimated to result in the least amount (1.24) of PFQALYs, followed by VRd at 1.35 PFQALYs and DRd at 1.52 PFQALYs. With a WTP threshold of $150,000 per PFQALY, VRd was not cost-effective compared with Rd standard therapy, with an incremental cost-effectiveness ratio (ICER) of $530,256 per PFQALY. DRd was not cost-effective compared with VRd (ICER = $1,396,318 per PFQALY), nor as compared with Rd standard therapy (ICER = $1060,832). One-way sensitivity analysis showed that our model was sensitive to cost of DRd, VRd, and Rd drugs. Probabilistic sensitivity analysis showed that only at a WTP threshold of $550,000 was VRd cost-effective for 40% of iterations. There were no reasonable WTP thresholds, up to $800,00, where DRd became more cost-effective than VRd. CONCLUSIONS: This study is the first analysis to directly compare the cost-effectiveness of 3 acceptable chemotherapy treatment regimens for patients with multiple myeloma ineligible for autologous stem cell transplant. Neither DRd nor VRd triple therapy were found to be cost-effective vs Rd. Further cost-effectiveness analyses that include overall survival data for daratumumab and bortezomib triple therapies are needed to demonstrate an ICER in QALYs. DISCLOSURES: No funding was received for this study. At the time of this study, Narsipur was a UCSF-Actelion Clinical Research and Medical Communications Fellow, unrelated to this study. The other authors have nothing to disclose.

Fluorouracil plasma monitoring: systematic review and economic evaluation of the My5-FU assay for guiding dose adjustment in patients receiving fluorouracil chemotherapy by continuous infusion

BACKGROUND

5-Fluorouracil (5-FU) is a chemotherapy used in colorectal, head and neck (H&N) and other cancers. Dose adjustment is based on body surface area (BSA) but wide variations occur. Pharmacokinetic (PK) dosing is suggested to bring plasma levels into the therapeutic range to promote fewer side effects and better patient outcomes. We investigated the clinical effectiveness and cost-effectiveness of the My5-FU assay for PK dose adjustment to 5-FU therapy.

OBJECTIVES

To systematically review the evidence on the accuracy of the My5-FU assay compared with gold standard methods [high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS)]; the effectiveness of My5-FU PK dosing compared with BSA; the effectiveness of HPLC and/or LC-MS compared with BSA; the generalisability of published My5-FU and PK studies; costs of using My5-FU; to develop a cost-effectiveness model.

DATA SOURCES

We searched MEDLINE, EMBASE, Science Citation Index and other databases between January and April 2014.

METHODS

Two reviewers independently screened titles and abstracts with arbitration and consensus agreement. We undertook quality assessment. We reconstructed Kaplan-Meier plots for progression-free survival (PFS) and overall survival (OS) for comparison of BSA and PK dosing. We developed a Markov model to compare My5-FU with BSA dosing which modelled PFS, OS and adverse events, using a 2-week cycle over a 20 year time horizon with a 3.5% discount rate. Health impacts were evaluated from the patient perspective, while costs were evaluated from the NHS and Personal Social Services perspective.

RESULTS

A total of 8341 records were identified through electronic searches and 35 and 54 studies were included in the clinical effectiveness and cost-effectiveness reviews respectively. There was a high apparent correlation between My5-FU, HPLC and LC-MS/mass spectrometer but upper and lower limits of agreement were -18% to 30%. Median OS were estimated as 19.6 [95% confidence interval (CI) 17.0 to 21.0] months for PK versus 14.6 (95% CI 14.1 to 15.3) months for BSA for 5-FU+folinic acid (FA); and 27.4 (95% CI 23.2 to 38.8) months for PK versus 20.6 (95% CI 18.4 to 22.9) months for BSA for FOLFOX6 in metastatic colorectal cancer (mCRC). PK versus BSA studies were generalisable to the relevant populations. We developed cost-effectiveness models for mCRC and H&N cancer. The base case assumed a cost per My5-FU assay of £ 61.03. For mCRC for 12 cycles of a oxaliplatin in combination with 5-fluorouracil and FA (FOLFOX) regimen, there was a quality-adjusted life-year (QALY) gain of 0.599 with an incremental cost-effectiveness ratio of £ 4148 per QALY. Probabilistic and scenario analyses gave similar results. The cost-effectiveness acceptability curve showed My5-FU to be 100% cost-effective at a threshold of £ 20,000 per QALY. For H&N cancer, again, given caveats about the poor evidence base, we also estimated that My5-FU is likely to be cost-effective at a threshold of £ 20,000 per QALY.

LIMITATIONS

Quality and quantity of evidence were very weak for PK versus BSA dosing for all cancers with no randomised controlled trials (RCTs) using current regimens. For H&N cancer, two studies of regimens no longer in use were identified.

CONCLUSIONS

Using a linked evidence approach, My5-FU appears to be cost-effective at a willingness to pay of £ 20,000 per QALY for both mCRC and H&N cancer. Considerable uncertainties remain about evidence quality and practical implementation. RCTs are needed of PK versus BSA dosing in relevant cancers.

A systematic review of utility values for chemotherapy-related adverse events

BACKGROUND

Chemotherapy offers cancer patients the potential benefits of improved mortality and morbidity but may cause detrimental outcomes due to adverse drug events (ADEs), some of which requiring time-consuming, resource-intensive and costly clinical management. To appropriately assess chemotherapy agents in an economic evaluation, ADE-related parameters such as the incidence, (dis)utility and cost of ADEs should be reflected within the model parameters. To date, there has been no systematic summary of the existing literature that quantifies the utilities of ADEs due to healthcare interventions in general and chemotherapy treatments in particular.

OBJECTIVE

This review aimed to summarize the current evidence base of reported utility values for chemotherapy-related ADEs.

METHODS

A structured electronic search combining terms for utility, utility valuation methods and generic terms for cancer treatment was conducted in MEDLINE and EMBASE in June 2011. Inclusion criteria were: (1) elicitation of utility values for chemotherapy-related ADEs and (2) primary data. Two reviewers identified studies and extracted data independently. Any disagreements were resolved by a third reviewer.

RESULTS

Eighteen studies met the inclusion criteria from the 853 abstracts initially identified, collectively reporting 218 utility values for chemotherapy-related ADEs. All 18 studies used short descriptions (vignettes) to obtain the utility values, with nine studies presenting the vignettes used in the valuation exercises. Of the 218 utility values, 178 were elicited using standard gamble (SG) or time trade-off (TTO) approaches, while 40 were elicited using visual analogue scales (VAS). There were 169 utility values of specific chemotherapy-related ADEs (with the top ten being anaemia [34 values], nausea and/or vomiting [32 values], neuropathy [21 values], neutropenia [12 values], diarrhoea [12 values], stomatitis [10 values], fatigue [8 values], alopecia [7 values], hand-foot syndrome [5 values] and skin reaction [5 values]) and 49 of non-specific chemotherapy-related adverse events. In most cases, it was difficult to directly compare the utility values as various definitions and study-specific vignettes were used for the ADEs of interest.

LIMITATIONS

This review was designed to provide an overall description of existing literature reporting utility values for chemotherapy-related ADEs. The findings were not exhaustive and were limited to publications that could be identified using the search strategy employed and those reported in the English language.

CONCLUSIONS

This review identified wide ranges in the utility values reported for broad categories of specific chemotherapy-related ADEs. There were difficulties in comparing the values directly as various study-specific definitions were used for these ADEs and most studies did not make the vignettes used in the valuation exercises available. It is recommended that a basic minimum requirement be developed for the transparent reporting of study designs eliciting utility values, incorporating key criteria such as reporting how the vignettes were developed and presenting the vignettes used in the valuation tasks as well as valuing and reporting the utility values of the ADE-free base states. It is also recommended, in the future, for studies valuing the utilities of chemotherapy-related ADEs to define the ADEs according to the National Cancer Institute (NCI) definitions for chemotherapy-related ADEs as the use of the same definition across studies would ease the comparison and selection of utility values and make the overall inclusion of adverse events within economic models of chemotherapy agents much more straightforward.

Assessment of respondent acceptability for preference measures in stuttering

PURPOSE

To assess the feasibility of using one or more of four standard economic preference measures to assess health-related quality of life in stuttering, by assessing respondents' views of the acceptability of those measures.

METHOD AND RESULTS

A graphic positioning scale approach was used with 80 adults to assess four variables previously defined as reflecting the construct of respondent acceptability (difficulty of decision making, clarity of text, reasonableness for decision making, and comfort in decision making) for four types of preference measurement approaches (rating scale, standard gamble, time trade-off, and willingness to pay). A multivariate repeated measures analysis of variance (p<.001) and follow-up univariate repeated measures analyses of variance (all p<.01) were all significant, indicating that respondents perceived differences among the preference measurement methods on all four acceptability variables.

CONCLUSION

The rating scale was perceived as the easiest, clearest, most reasonable, and most comfortable tool, but it is not a measure of utility (an economic term for desirability or worth). If utility is the objective, such as for cost-utility analyses in stuttering, then the present results suggest the use of standard gamble (rather than time trade-off). These results also support the use of willingness to pay assessments for cost-benefit analyses in stuttering. These findings supplement results previously obtained for other chronic conditions.

LEARNING OUTCOMES

The reader will be able to: (1) describe how four standard economic preference measures [rating scale (RS), time trade-off (TTO), standard gamble (SG), and willingness to pay (WTP)] can be used in economic analyses; (2) describe how RS, TTO, SG and WTP can be measured; and (3) describe how respondents perceive the use of RS, TTO, SG and WTP in measuring changes in stuttering.

Empirical validation of patient versus population preferences in calculating QALYs

A fundamental assumption of the quality-adjusted life year model is mutual utility independence between life years and health status. However, this assumption may not hold for severe health states: living in a severe health state may cause disutility beyond a so-called maximal endurable time (MET). It is unknown, however, whether persons without experience of a disease, who are often used in health state valuation exercises, account for MET. Using data from 159 respondents from two convenience samples in Germany who were presented a health state description of depression, this study shows that persons without experience of depression had a lower rate of MET than persons with a history of depression. Furthermore, they had more preference reversals in case of MET, thus violating a fundamental principle of rational choice theory. While these findings suggest that severe health states should be assessed by patients rather than the community, confirmation in additional studies outside Germany and based on other health-state valuation techniques and diseases is recommended.

Health-state utility values in breast cancer

Health-related quality of life is an important issue in the treatment of breast cancer and health-state utility values are essential for cost-utility analysis. A literature review was conducted to identify published values for common health states for breast cancer. In total, 13 databases were searched and 49 articles were identified providing 476 unique utility values. Where possible mean utility estimates were pooled using ordinary least squares with utilities clustered within study group and weighted by both number of respondents and inverse of the variance of each utility. Regressions included controls for disease state, utility assessment method and other features of study design. Utility values found in the review were summarized for six categories: screening-related states; preventative states; adverse events in breast cancer and its treatment; nonspecific breast cancer; metastatic breast cancer states; and early breast cancer states. The large number of values identified for metastatic breast cancer and early breast cancer states enabled data to be synthesized by meta-regression. Utilities were found to vary significantly between valuation methods and depending on who conducted the valuation. For metastatic breast cancer, values significantly varied by severity of condition, treatment and side-effects. Despite the numerous studies it is not feasible to generate a definitive list of health-state utility values that can be used in future economic evaluations owing to the complexity of the health states involved and the variety of methods used to obtain values. Future research into quality of life in breast cancer should make greater use of validated generic preference-based measures for which public preferences exist.

The duration effect: a link between TTO and VAS values

The value of a health state may depend on how long an individual has had to endure the health state (i.e. hedonic load). In this paper, we test the constant proportionality (CP) assumption and determine the sign of relationship between duration and health state value for 42 health states using the nationally representative data from the United Kingdom Measurement and Valuation of Health study. The results reject the CP assumption and suggest that the relationship is negative for optimal health (i.e. fair innings argument) and that the relationship is positive for poorer health states (i.e. adaptation). We find no evidence of the maximum endurable time hypothesis using these data. This evidence on the duration effect has important implications for outcomes research and the economic evaluation of interventions.

Estimating Preference Scores in Conventional and Home Nocturnal Hemodialysis Patients

Previous studies have reported higher quality of life in patients who receive home nocturnal hemodialysis (HNHD) than conventional in-center hemodialysis (IHD). The optimal method for eliciting preferences from dialysis patients remains undefined, and there may be unique methodologic concerns in this population. Patients' preferences for IHD (n = 20) and HNHD (n = 24) were studied using the standard gamble (SG), time trade-off (TTO), and modified willingness to pay (WTP) methods. This report describes experience with operationalizing these three techniques in this population. A higher preference for HNHD was found with all measures, with significant differences observed with the SG (HNHD: median 0.79 [interquartile range (IQR) 0.67 to 0.95]; IHD: median 0.60 [IQR 0.20 to 0.82]; P = 0.031) and WTP (HNHD: median 0.50 [IQR 0.40 to 0.68]; IHD: median 0.20 [IQR 0.20 to 0.38]; P < 0.001). SG and TTO scores were moderately correlated but not with WTP. In addition, qualitative issues arose during TTO and WTP interviews that seemed to influence the interpretation of these preference scores. In the TTO, time willing to trade became oriented toward the next pivotal life event, with a failure of the requirement for a constant proportional time trade-off. WTP preferences were oriented toward the smallest survival stipend. These issues represent range restriction biases. No significant issues arose during the SG interviews. HNHD patients expressed a greater preference for current health than IHD patients. The operational performance of SG was good in this study, whereas biases and methodologic concerns were identified with the TTO and WTP in this population.

Can differences in breast cancer utilities explain disparities in breast cancer care?

BACKGROUND

Black, older, and less affluent women are less likely to receive adjuvant breast cancer therapy than their counterparts. Whereas preference contributes to disparities in other health care scenarios, it is unclear if preference explains differential rates of breast cancer care.

OBJECTIVE

To ascertain utilities from women of diverse backgrounds for the different stages of, and treatments for, breast cancer and to determine whether a treatment decision modeled from utilities is associated with socio-demographic characteristics.

PARTICIPANTS

A stratified sample (by age and race) of 156 English-speaking women over 25 years old not currently undergoing breast cancer treatment.

DESIGN AND MEASUREMENTS

We assessed utilities using standard gamble for 5 breast cancer stages, and time-tradeoff for 3 therapeutic modalities. We incorporated each subject's utilities into a Markov model to determine whether her quality-adjusted life expectancy would be maximized with chemotherapy for a hypothetical, current diagnosis of stage II breast cancer. We used logistic regression to determine whether socio-demographic variables were associated with this optimal strategy.

RESULTS

Median utilities for the 8 health states were: stage I disease, 0.91 (interquartile range 0.50 to 1.00); stage II, 0.75 (0.26 to 0.99); stage III, 0.51 (0.25 to 0.94); stage IV (estrogen receptor positive), 0.36 (0 to 0.75); stage IV (estrogen receptor negative), 0.40 (0 to 0.79); chemotherapy 0.50 (0 to 0.92); hormonal therapy 0.58 (0 to 1); and radiation therapy 0.83 (0.10 to 1). Utilities for early stage disease and treatment modalities, but not metastatic disease, varied with socio-demographic characteristics. One hundred and twenty-two of 156 subjects had utilities that maximized quality-adjusted life expectancy given stage II breast cancer with chemotherapy. Age over 50, black race, and low household income were associated with at least 5-fold lower odds of maximizing quality-adjusted life expectancy with chemotherapy, whereas women who were married or had a significant other were 4-fold more likely to maximize quality-adjusted life expectancy with chemotherapy.

CONCLUSIONS

Differences in utility for breast cancer health states may partially explain the lower rate of adjuvant therapy for black, older, and less affluent women. Further work must clarify whether these differences result from health preference alone or reflect women's perceptions of sources of disparity, such as access to care, poor communication with providers, limitations in health knowledge or in obtaining social and workplace support during therapy.

Using preference-based measures to assess quality of life in stuttering

PURPOSE

The purpose of this study was to determine whether standard pharmaco-economic preference methods can be used to assess perceived quality of life in stuttering.

METHOD

Seventy-five nonstuttering adults completed a standardized face-to-face interview that included a rating scale, standard gamble, and time trade-off preference measures for 4 health states (your health and mild, moderate, and severe stuttering) in the context of 2 anchor states (perfect health and death).

RESULTS

Results showed mean utility values between .443 for severe stuttering estimated using the rating scale technique and .982 for respondents' own current health estimated using a standard gamble technique. A two-way repeated measures analysis of variance and post hoc tests showed significant effects for method, health state, and the interaction.

CONCLUSIONS

These results confirm that utility estimates can differentiate between stuttering severity levels and that utility scores for stuttering conform to the known properties of data obtained using these standard measurement techniques. These techniques, therefore, can and should be further investigated as potential contributors to complete measurement protocols for the study and treatment of stuttering.

Quality-adjusted life years was a poor predictor of women's willingness to pay in acute and chronic conditions: results of a survey

OBJECTIVE

We investigated the relationship between quality-adjusted life years (QALYs) and willingness to pay (WTP) in acute and chronic conditions.

STUDY DESIGN AND SETTING

Face-to-face interviews were used to collect data in a convenience sample of women. Participants completed one interview evaluating preferences for an acute condition, post-chemotherapy nausea and vomiting (PCNV), and the other interview for a chronic condition (breast cancer). Preferences were elicited for QALYs using visual analogue scale (VAS), and standard gamble in addition to WTP. Because QALYs and WTP are purportedly based on the same underlying theoretical foundations, WTP was regressed onto change in QALYs, age, income, and health status.

RESULTS

Regression analysis reported statistically significant models for all breast cancer (P < .001) and PCNV (P < .05) conditions tested. However, QALY was not a significant predictor of WTP.

CONCLUSION

The results of this study indicate QALYs was a poor predictor of WTP for the conditions tested. Linear combinations of change in QALYs, age, income, and health status were a better predictor of WTP for chronic than acute conditions. This can be attributed to violations of underlying assumptions in measurement of QALYs with acute conditions and to problems with the use of WTP with chronic conditions.

Assessment of respondent acceptability of preference measures: discriminatory power of graphic positioning scale versus traditional scaling measures

OBJECTIVE

The objective of this study was to compare discriminatory power of two different measures-graphic positioning scale (GPS) versus traditional scale (TS)-in assessing respondent acceptability of three preference measures: visual analog scale (VAS), standard gamble (SG), and willingness to pay (WTP).

METHODS

Two face-to-face interviews were conducted at least 1 week apart in a convenience sample of women aged 22 to 50 years with no history of breast cancer or cancer requiring chemotherapy. Study participation required completion of two surveys: one evaluating health preferences for an acute condition (chemotherapy-induced nausea and vomiting) and one evaluating a chronic condition (breast cancer). Data were collected from March 2000 to June 2000 at Ohio State University. Respondents were randomized to either GPS or TS surveys. Data analysis was a two-step process. First, a four-way multivariate repeated-measures analysis of variance (MANOVA) was conducted to assess respondent acceptability of three-preference metrics-VAS, SG, and WTP-in health-care decision making. Each of the four dependent variables, difficulty, clarity, reasonableness, and comfort in use in decision making, was measured on 9-point Likert scale. Second, a mixed design univariate analysis of variance (ANOVA) was performed for each dependent variable to optimize MANOVA analysis. Univariate ANOVAs, 2 x (2 x 3), were composed of three independent variables: assessment (GPS/TS), condition (acute and chronic), and preferences (VAS, SG, WTP).

RESULTS

Of 126 respondents, 119 were usable and complete. MANOVA results showed (P <.05) for two main effects, condition (F4,114 = 6.375) and preferences (F8,110 = 9.290), and two significant interactions, condition x assessment (F4,114 = 3.421) and condition x preferences (F8,110 = 2.087).

CONCLUSION

GPS has higher discriminatory power than TS in assessing respondent attitudes toward health preference measures. Results showed that respondents had more difficulty and less comfort when making decisions for chronic than for acute conditions. Results also show that respondents regard WTP as a more reasonable decision-making tool when assessing acute interventions in preference to SG and vice versa for chronic conditions. Of VAS, SG, and WTP methods, VAS was perceived as being the easiest to understand. These results can be explained by direct versus indirect comparisons made with GPS and TS methods, respectively.