Q-TWiST analysis of lapatinib combined with capecitabine for the treatment of metastatic breast cancer

Quality-Adjusted Survival in Patients with Recurrence of Breast Cancer Diagnosed by Asymptomatic or Symptomatic Opportunities

After radical surgery for breast cancer, screening to diagnose recurrence in asymptomatic patients is not recommended. We retrospectively evaluated quality-adjusted survival. Included were fifty-seven recurrent breast cancer patients who died. Survival was partitioned into 3 health states by two different definitions: definition a) time with toxicities due to chemotherapy before progression (TOX1), time from the diagnosis of recurrence to progression without toxicities (TWiST1), and time from progression to death (REL1); definition b) time from the diagnosis of recurrence to death with toxicities (TOX2), without toxicities or hospitalization (TWiST2), and with hospitalization (REL2). Q-TWiST was calculated by multiplying the time in each health state by its utility (uTOX, uTWiST, and uREL). In threshold analyses, uTOX and uREL ranged from 0.0 to 1.0 whereas uTWiST was maintained at 1.0. We compared the patients with (n=32) and without (n=25) symptoms at the time of the diagnosis of recurrence. There was no difference in overall survival after primary surgery, although survival after the diagnosis of recurrence was significantly longer in the asymptomatic patients (p<0.01). Q-TWiST1 and Q-TWiST2 from the diagnosis of recurrence in the asymptomatic patients were significantly longer. Q-TWiST2 from primary surgery in the asymptomatic patients was significantly longer with some combinations of higher uTOX2 and lower uREL2. In conclusion, the asymptomatic detection of recurrence was associated with significantly longer quality-adjusted survival in comparison to symptomatic detection with some combinations of uTOX2 and uREL2. A prospective evaluation would clarify adequate follow-up methods after radical surgery for breast cancer.

Cost-effectiveness of talazoparib for patients with locally advanced or metastasized breast cancer in Germany

This study evaluated factors that influence the cost-effectiveness of talazoparib, particularly for patients with a germline breast-cancer-gene-(brca)-mutation and locally advanced or metastasized breast cancer within the context of the German healthcare system. We constructed a partitioned survival model to compare medical costs and treatment effectiveness for patients with such cancers over 45 months. Transition probabilities were derived from survival data from a randomized Phase-III EMBRACA trial, utilities based on published reports, and costs in Euros, which included costs for drug acquisition, clinical monitoring, and treatment of adverse events. Willingness-to-pay thresholds were set to be multiples of the current German per capita gross domestic product. Treatment with talazoparib led to a gain of 0.32 life-years (0.22 quality-adjusted life-years). The mean total cost of €84,003 for talazoparib and €12,741 for standard therapy resulted in an incremental cost-effectiveness ratio of €223,246 per life-year and €323,932 per quality-adjusted life-year gained, indicating that talazoparib is unlikely to be cost-effective at current pricing.

Q-TWiST analysis of pembrolizumab combined with chemotherapy as first-line treatment of metastatic triple-negative breast cancer that expresses PD-L1

OBJECTIVE

In the KEYNOTE-355 (KN355) trial, pembrolizumab in combination with chemotherapy demonstrated superior efficacy and manageable safety compared with chemotherapy alone in patients with previously untreated locally recurrent inoperable and metastatic triple-negative breast cancer (mTNBC) with PD-L1 positive (Combined Positive Score [CPS]≥ 10) tumours. This study aimed to evaluate the clinical benefits and risks of pembrolizumab measured by quality-adjusted survival in the trial population.

METHODS

The study used data from the final analysis of KN355. The Quality-adjusted Time Without Symptoms of disease progression or Toxicity of treatment (Q-TWiST) analysis was used to compare treatments of pembrolizumab plus chemotherapy versus chemotherapy alone. Patients' survival time was partitioned into three health states - toxicity before disease progression (TOX), time without symptoms or toxicity before disease progression (TWiST), and relapse (REL). Utilities for these health states were estimated using EuroQol-5 Dimensions, 3 Levels (EQ-5D-3L) data collected in KN355. Q-TWiST was derived as the utility-weighted sum of the mean health state durations.

RESULTS

Patients randomised to pembrolizumab plus chemotherapy had 3.7 months greater Q-TWiST (relative gain of 18%; P = 0.003) compared to those randomised to chemotherapy at the median follow-up of 44 months, and 4.3 months greater Q-TWiST (relative gain of 20%; P = 0.004) at the maximum follow-up of 52 months. The Q-TWiST gain increased with longer follow-up time.

CONCLUSIONS

Pembrolizumab plus chemotherapy was associated with statistically significant and clinically important improvement in Q-TWiST compared to chemotherapy in previously untreated PD-L1-positive mTNBC.

A Systematic Literature Review of Health Utility Values in Breast Cancer

BACKGROUND

Health utility values (HUVs) are important inputs to the cost-utility analysis of breast cancer interventions.

PURPOSE

Provide a catalog of breast cancer-related published HUVs across different stages of breast cancer and treatment interventions.

DATA SOURCES

Systematic searches of MEDLINE, MEDLINE In-Process, EMBASE, Web of Science, CINAHL, PsycINFO, EconLit, and Cochrane databases (2005-2017).

STUDY SELECTION

Studies published in English that reported mean or median HUVs using direct or indirect methods of utility elicitation for breast cancer.

DATA EXTRACTION

Independent reviewers extracted data on a preestablished and piloted form; disagreements were resolved through discussion.

DATA ANALYSIS

Mixed-effects meta-regression using restricted maximum likelihood modeling was conducted for intervention type, stage of breast cancer, and typical clinical and treatment trajectory of breast cancer patients to assess the effect of study characteristics (i.e., sample size, utility elicitation method, and respondent type) on HUVs.

DATA SYNTHESIS

Seventy-nine studies were included in the review. Most articles (n = 52, 66%) derived HUVs using the EQ-5D. Patients with advanced-stage breast cancer (range, 0.08 to 0.82) reported lower HUVs as compared with patients with early-stage breast cancer (range, 0.58 to 0.99). The meta-regression analysis found that undergoing chemotherapy and surgery and radiation, being diagnosed with an advanced stage of breast cancer, and recurrent cancer were associated with lower HUVs. The members of the general public reported lower HUVs as compared with patients.

LIMITATIONS

There was considerable heterogeneity in the study population, health states assessed, and utility elicitation methods.

CONCLUSION

This review provides a catalog of published HUVs related to breast cancer. The substantial heterogeneity in the health utility studies makes it challenging for researchers to choose which HUVs to use in cost-utility analyses for breast cancer interventions.

Cost-Effectiveness Analysis of Adding Palbociclib as a Second-Line Endocrine Therapy for HR+/HER2- Metastatic Breast Cancer From the US and Chinese Perspectives

PURPOSE

As a second-line endocrine therapy for hormone receptor-positive and human epidermal growth factor receptor 2-negative (HR⁺/HER2^-) metastatic breast cancer, palbociclib has demonstrated significant efficacy in prolonging progression-free survival when added to a regimen containing fulvestrant. The objective of this study was to evaluate the cost-effectiveness of palbociclib from the perspectives of the United States and China.

METHODS

We developed a Markov model to estimate lifetime costs, overall life-years gained, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs). One-way and probabilistic sensitivity analyses were performed to predict the uncertainty of the model developed. The time horizon was 10 years, and the perspective was that of the payer.

FINDINGS

Within a 10-year time horizon, the palbociclib-containing strategy provided an additional 0.568 QALY, with an ICER of 88,854 USD/QALY, in the United States. When palbociclib cost 30%, 20%, and 10% of the current price, the ICERs were 185,526, 42,193, and 98,860 USD/QALY, respectively. In China, the ICER was 182,779 USD/QALY. When palbociclib cost 30%, 20%, and 10% of the current price, the ICERs were 79,558, 64,812, and 50,066 USD/QALY, respectively. In order to meet 50% probability of cost-effectiveness, the estimated price would have to be 32.52 USD/100 mg at a willingness-to-pay threshold of 58,480 USD/QALY (3 × per-capita domestic product of Beijing, China).

IMPLICATIONS

Adding palbociclib to a regimen of fulvestrant is unlikely to be cost-effective as a second-line endocrine therapy for HR⁺/HER2^- metastatic breast cancer (MBC) with at the current price in the United States and China. For widely meeting the treatment demands of patients, it may be a better option to decrease the price or provide more patients with a financial assistance program for palbociclib both in the United States and in China.

Systematic review and benchmarking of Quality-Adjusted Time Without Symptoms or Toxicity (Q-TWiST) in oncology

INTRODUCTION

The Quality-Adjusted Time Without Symptoms or Toxicity (Q-TWiST) has been used to evaluate the clinical benefits and risks of oncology treatments. However, limited information is available to interpret and contextualize Q-TWiST results.

AREAS COVERED

A systematic review of Q-TWiST literature was conducted to provide contextualizing benchmarks for future studies. 51 articles with 81 unique Q-TWiST comparisons were identified. The mean (95% CI) and median absolute Q-TWiST gains for treatment versus control arms were 2.78 (1.82-3.73) months and 2.20 months across all cancers, respectively. The mean (median) relative Q-TWiST gains were 7.8% (7.2%) across all cancers. Most (88%) studies reported positive gains. The percentage of studies with relative Q-TWiST gains ≥10% (ie, clinically important difference) and ≥15% (ie, clearly clinically important difference) were 40.0% and 22.7%, respectively

EXPERT COMMENTARY

The relevance of Q-TWiST in assessing net clinical benefits of cancer therapy has not diminished, despite an arguably low number of published studies. The interest in such assessment is highlighted by the recent emergence of oncology value frameworks. The Q-TWiST should be compelling to clinicians as it integrates clinical information (ie, toxicity, relapse/progression, and survival) and patient preferences for each of these states into a single meaningful index.

Health state utility values in locally advanced and metastatic breast cancer by treatment line: a systematic review

INTRODUCTION

For patients with late-stage (metastatic) breast cancer, the impact of treatment on health-related quality of life is a key factor in decision-making. A systematic review was conducted to identify health state utility values (HSUVs) for late-stage breast cancer, derived using methods preferred by health technology assessment (HTA) agencies, by treatment line. The aim was to generate a list of HSUVs, that could help to justify the values used to populate cost-utility models. Areas covered: Ten electronic databases, international congress websites and online HSUV databases were searched (January 1995-May 2014) for HSUVs for adults with late-stage breast cancer that had been derived from methods favoured by HTA agencies. Publications were included only if they reported studies that originated HSUVs. Expert commentary: Large numbers of HSUVs are available for late-stage breast cancer in the published literature. Contrary to expectations, the HSUVs reported in the literature vary greatly for some health states. As a result, the choice of HSUV can have considerable implications for the outcomes of economic evaluations. Standardization of HSUV methodology is expected to reduce variability; however, further research is recommended for assessing the sensitivity of generic preference-based measures in late-stage (metastatic) breast cancer.

A structured review of health utility measures and elicitation in advanced/metastatic breast cancer

BACKGROUND

Health utilities are increasingly incorporated in health economic evaluations. Different elicitation methods, direct and indirect, have been established in the past. This study examined the evidence on health utility elicitation previously reported in advanced/metastatic breast cancer and aimed to link these results to requirements of reimbursement bodies.

METHODS

Searches were conducted using a detailed search strategy across several electronic databases (MEDLINE, EMBASE, Cochrane Library, and EconLit databases), online sources (Cost-effectiveness Analysis Registry and the Health Economics Research Center), and web sites of health technology assessment (HTA) bodies. Publications were selected based on the search strategy and the overall study objectives.

RESULTS

A total of 768 publications were identified in the searches, and 26 publications, comprising 18 journal articles and eight submissions to HTA bodies, were included in the evidence review. Most journal articles derived utilities from the European Quality of Life Five-Dimensions questionnaire (EQ-5D). Other utility measures, such as the direct methods standard gamble (SG), time trade-off (TTO), and visual analog scale (VAS), were less frequently used. Several studies described mapping algorithms to generate utilities from disease-specific health-related quality of life (HRQOL) instruments such as European Organization for Research and Treatment of Cancer Quality of Life Questionnaire - Core 30 (EORTC QLQ-C30), European Organization for Research and Treatment of Cancer Quality of Life Questionnaire - Breast Cancer 23 (EORTC QLQ-BR23), Functional Assessment of Cancer Therapy - General questionnaire (FACT-G), and Utility-Based Questionnaire-Cancer (UBQ-C); most used EQ-5D as the reference. Sociodemographic factors that affect health utilities, such as age, sex, income, and education, as well as disease progression, choice of utility elicitation method, and country settings, were identified within the journal articles. Most submissions to HTA bodies obtained utility values from the literature rather than exploring the HRQOL data obtained during clinical development. This was critiqued by the National Institute for Health and Clinical Excellence (NICE). Furthermore, the impact of age on utilities was highlighted by NICE and it was suggested that an age match of the study population should be attempted.

CONCLUSION

Health utilities are recorded across the globe to varying extents and using differing elicitation methods. Manufacturers seeking reimbursement need to be aware of the country-specific requirements for elicitation of health utilities.

The INTRABEAM® Photon Radiotherapy System for the adjuvant treatment of early breast cancer: a systematic review and economic evaluation

BACKGROUND

Initial treatment for early breast cancer is usually either breast-conserving surgery (BCS) or mastectomy. After BCS, whole-breast external beam radiotherapy (WB-EBRT) is the standard of care. A potential alternative to post-operative WB-EBRT is intraoperative radiation therapy delivered by the INTRABEAM(®) Photon Radiotherapy System (Carl Zeiss, Oberkochen, Germany) to the tissue adjacent to the resection cavity at the time of surgery.

OBJECTIVE

To assess the clinical effectiveness and cost-effectiveness of INTRABEAM for the adjuvant treatment of early breast cancer during surgical removal of the tumour.

DATA SOURCES

Electronic bibliographic databases, including MEDLINE, EMBASE and The Cochrane Library, were searched from inception to March 2014 for English-language articles. Bibliographies of articles, systematic reviews, clinical guidelines and the manufacturer's submission were also searched. The advisory group was contacted to identify additional evidence.

METHODS

Systematic reviews of clinical effectiveness, health-related quality of life and cost-effectiveness were conducted. Two reviewers independently screened titles and abstracts for eligibility. Inclusion criteria were applied to full texts of retrieved papers by one reviewer and checked by a second reviewer. Data extraction and quality assessment were undertaken by one reviewer and checked by a second reviewer, and differences in opinion were resolved through discussion at each stage. Clinical effectiveness studies were included if they were carried out in patients with early operable breast cancer. The intervention was the INTRABEAM system, which was compared with WB-EBRT, and study designs were randomised controlled trials (RCTs). Controlled clinical trials could be considered if data from available RCTs were incomplete (e.g. absence of data on outcomes of interest). A cost-utility decision-analytic model was developed to estimate the costs, benefits and cost-effectiveness of INTRABEAM compared with WB-EBRT for early operable breast cancer.

RESULTS

One non-inferiority RCT, TARGeted Intraoperative radioTherapy Alone (TARGIT-A), met the inclusion criteria for the review. The review found that local recurrence was slightly higher following INTRABEAM than WB-EBRT, but the difference did not exceed the 2.5% non-inferiority margin providing INTRABEAM was given at the same time as BCS. Overall survival was similar with both treatments. Statistically significant differences in complications were found for the occurrence of wound seroma requiring more than three aspirations (more frequent in the INTRABEAM group) and for a Radiation Therapy Oncology Group toxicity score of grade 3 or 4 (less frequent in the INTRABEAM group). Cost-effectiveness base-case analysis indicates that INTRABEAM is less expensive but also less effective than WB-EBRT because it is associated with lower total costs but fewer total quality-adjusted life-years gained. However, sensitivity analyses identified four model parameters that can cause a switch in the treatment option that is considered cost-effective.

LIMITATIONS

The base-case result from the model is subject to uncertainty because the disease progression parameters are largely drawn from the single available RCT. The RCT median follow-up of 2 years 5 months may be inadequate, particularly as the number of participants with local recurrence is low. The model is particularly sensitive to this parameter.

CONCLUSIONS AND IMPLICATIONS

A significant investment in INTRABEAM equipment and staff training (clinical and non-clinical) would be required to make this technology available across the NHS. Longer-term follow-up data from the TARGIT-A trial and analysis of registry data are required as results are currently based on a small number of events and economic modelling results are uncertain.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013006720.

FUNDING

The National Institute for Health Research Health Technology Assessment programme. Note that the economic model associated with this document is protected by intellectual property rights, which are owned by the University of Southampton. Anyone wishing to modify, adapt, translate, reverse engineer, decompile, dismantle or create derivative work based on the economic model must first seek the agreement of the property owners.

Quality-adjusted time without symptoms or toxicity analysis of pazopanib versus sunitinib in patients with renal cell carcinoma

BACKGROUND

In a phase 3, randomized, open-label trial (Pazopanib versus Sunitinib in the Treatment of Locally Advanced and/or Metastatic Renal Cell Carcinoma, COMPARZ; NCT00720941), pazopanib was found to be noninferior to sunitinib in terms of progression-free survival in patients with metastatic renal cell carcinoma with no prior therapy. Overall treatment differences were evaluated in a post hoc analysis with a quality-adjusted time without symptoms or toxicity (Q-TWiST) methodology.

METHODS

Each patient's overall survival was partitioned into 3 mutually exclusive health states: time with grade 3 or 4 toxicity (TOX), time without symptoms of disease or grade 3/4 toxicity of treatment, and time after tumor progression or relapse (REL). The time spent in each state was weighted by a health-state utility associated with that state and summed to calculate the Q-TWiST. A threshold utility analysis was used, and utilities were applied across the range of 0 (similar to death) to 1 (perfect health).

RESULTS

A total of 1110 patients were enrolled (557 on pazopanib and 553 on sunitinib). The mean TOX was 31 days (95% confidence interval, 13-48 days) longer for sunitinib versus pazopanib. In the threshold utility analysis, the difference in the Q-TWiST ranged from -11 days (utility for TOX, 1; utility for REL, 0) to 43 days (utility for TOX, 0; utility for REL, 1) in favor of pazopanib across most utility combinations. Differences were significant in less than half of the utility combinations examined, and this typically occurred when the utility for TOX was lower than the utility for REL.

CONCLUSIONS

Patients randomized to pazopanib had a slightly longer Q-TWiST in comparison with sunitinib patients, and this was primarily due to the reduced length of TOX.

Integration of PKPD relationships into benefit-risk analysis

AIM

Despite the continuous endeavour to achieve high standards in medical care through effectiveness measures, a quantitative framework for the assessment of the benefit-risk balance of new medicines is lacking prior to regulatory approval. The aim of this short review is to summarise the approaches currently available for benefit-risk assessment. In addition, we propose the use of pharmacokinetic-pharmacodynamic (PKPD) modelling as the pharmacological basis for evidence synthesis and evaluation of novel therapeutic agents.

METHODS

A comprehensive literature search has been performed using MESH terms in PubMed, in which articles describing benefit-risk assessment and modelling and simulation were identified. In parallel, a critical review of multi-criteria decision analysis (MCDA) is presented as a tool for characterising a drug's safety and efficacy profile.

RESULTS

A definition of benefits and risks has been proposed by the European Medicines Agency (EMA), in which qualitative and quantitative elements are included. However, in spite of the value of MCDA as a quantitative method, decisions about benefit-risk balance continue to rely on subjective expert opinion. By contrast, a model-informed approach offers the opportunity for a more comprehensive evaluation of benefit-risk balance before extensive evidence is generated in clinical practice.

CONCLUSIONS

Benefit-risk balance should be an integral part of the risk management plan and as such considered before marketing authorisation. Modelling and simulation can be incorporated into MCDA to support the evidence synthesis as well evidence generation taking into account the underlying correlations between favourable and unfavourable effects. In addition, it represents a valuable tool for the optimization of protocol design in effectiveness trials.

Clinical experience with temsirolimus in the treatment of advanced renal cell carcinoma

Temsirolimus is an inhibitor of the mammalian target of rapamycin (mTOR) kinase, a protein that has been shown to be particularly active in metastatic renal cell carcinoma (mRCC) with poor prognosis. Therefore, temsirolimus should be considered as the first-line treatment indicated in mRCC patients classified as poor risk. The benefits of temsirolimus are not limited to an increased survival but are also related to a better quality of life, which is certainly one of the most important aspects in the clinical management of these frail patients. Temsirolimus is a well-tolerated treatment, and the most frequent adverse events are manageable with supportive care. To this end, the identification of predictive factors of response to temsirolimus could help us to better select patients and obtain a more tailored clinical management of mRCC.

Quality-adjusted time without symptoms or toxicity (Q-TWiST): patient-reported outcome or mathematical model? A systematic review in cancer

OBJECTIVE

Successful cancer treatment is defined as an increase in overall survival and/or progression-free survival. Despite their importance, these metrics omit patient quality of life. Quality-adjusted time without symptoms or toxicity (Q-TWiST) was developed to adjust survival gained, accounting for quality of life. The purpose of this systematic review was to assess the methods reported in cancer literature to determine Q-TWiST values and how these are currently translated to the clinic.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were used to conduct a systematic review of studies indexed on MEDLINE and Web of Science through April 2013. Cancer studies that measured Q-TWiST either as a primary outcome or retrospectively and determined utility coefficients from a patient population were identified, and their methods reviewed to determine how the utility coefficient was calculated. Additionally, other relevant factors such as definitions of health states and significant findings were collected and summarized.

RESULTS

Out of 284 studies, 11 were identified that calculated patient-defined utility coefficients. Several methods to determine utility coefficients were reported, and multiple definitions of health state toxicity were applied. Of these studies, seven reported significant differences (p < 0.05) in quality-adjusted survival. No studies, however, directly discussed the clinical relevance of their findings.

CONCLUSIONS

Currently, Q-TWiST is utilized as a mathematical theory rather than a clinical tool. Standardization of terminology plus reliability and validity testing of determining both utility coefficients and time frame definitions must be performed before Q-TWiST can become clinically useful to physicians and patients alike for making treatment decisions.

Cost-Effectiveness of Lapatinib plus Letrozole in Post-Menopausal Women with Hormone Receptor-and HER2-Positive Metastatic Breast Cancer

BACKGROUND

In the EGF30008 and TAnDEM (TrAstuzumab in Dual HER2 ER-positive Metastatic breast cancer) trials, anti-HER2 therapy plus an aromatase inhibitor (lapatinib + letrozole (LAP + LET) and trastuzumb + anastrozole (TZ + ANA), respectively) improved time to progression versus aromatase inhibitor monotherapy (LET and ANA, respectively) in post-menopausal women with previously untreated hormone receptor-positive (HR+) and HER2-positive (HER2+) metastatic breast cancer.

METHODS

A partitionedsurvival analysis model using data from EGF30008 and published results of TAnDEM and other literature was used to evaluate the incremental direct medical cost per quality-adjusted life year (QALY) gained with LAP + LET versus LET, ANA, and TZ + ANA in post-menopausal women with previously untreated HR+ and HER2+ metastatic breast cancer from the UK National Health Service (NHS) perspective.

RESULTS

Incremental costs for LAP + LET are £ 34,737 versus LET, £ 35,995 versus ANA, and £ 5,513 versus TZ + ANA. Corresponding QALYs gained are 0.467, 0.601, and 0.252 years. Cost/QALY gained with LAP + LET is £ 74,448 versus LET, £ 59,895 versus ANA, and £ 21,836 versus TZ + ANA. Given a threshold of £ 30,000/QALY, the estimated probability that LAP + LET is cost-effective is 1.4% versus LET, 9.2% versus ANA, and 51% versus TZ + ANA.

CONCLUSIONS

Based on criteria for the evaluation of health technologies in the UK (£ 30,000/QALY), LAP + LET is not likely to be cost-effective versus aromatase inhibitor monotherapy but may be cost-effective versus TZ + ANA, although the latter comparison is associated with substantial uncertainty.

A framework for organizing and selecting quantitative approaches for benefit-harm assessment

BACKGROUND

Several quantitative approaches for benefit-harm assessment of health care interventions exist but it is unclear how the approaches differ. Our aim was to review existing quantitative approaches for benefit-harm assessment and to develop an organizing framework that clarifies differences and aids selection of quantitative approaches for a particular benefit-harm assessment.

METHODS

We performed a review of the literature to identify quantitative approaches for benefit-harm assessment. Our team, consisting of clinicians, epidemiologists, and statisticians, discussed the approaches and identified their key characteristics. We developed a framework that helps investigators select quantitative approaches for benefit-harm assessment that are appropriate for a particular decisionmaking context.

RESULTS

Our framework for selecting quantitative approaches requires a concise definition of the treatment comparison and population of interest, identification of key benefit and harm outcomes, and determination of the need for a measure that puts all outcomes on a single scale (which we call a benefit and harm comparison metric). We identified 16 quantitative approaches for benefit-harm assessment. These approaches can be categorized into those that consider single or multiple key benefit and harm outcomes, and those that use a benefit-harm comparison metric or not. Most approaches use aggregate data and can be used in the context of single studies or systematic reviews. Although the majority of approaches provides a benefit and harm comparison metric, only four approaches provide measures of uncertainty around the benefit and harm comparison metric (such as a 95 percent confidence interval). None of the approaches considers the actual joint distribution of benefit and harm outcomes, but one approach considers competing risks when calculating profile-specific event rates. Nine approaches explicitly allow incorporating patient preferences.

CONCLUSION

The choice of quantitative approaches depends on the specific question and goal of the benefit-harm assessment as well as on the nature and availability of data. In some situations, investigators may identify only one appropriate approach. In situations where the question and available data justify more than one approach, investigators may want to use multiple approaches and compare the consistency of results. When more evidence on relative advantages of approaches accumulates from such comparisons, it will be possible to make more specific recommendations on the choice of approaches.

Low or undetectable TPO receptor expression in malignant tissue and cell lines derived from breast, lung, and ovarian tumors

BACKGROUND

Numerous efficacious chemotherapy regimens may cause thrombocytopenia. Thrombopoietin receptor (TPO-R) agonists, such as eltrombopag, represent a novel approach for the treatment of chemotherapy-induced thrombocytopenia. The TPO-R MPL is expressed on megakaryocytes and megakaryocyte precursors, although little is known about its expression on other tissues.

METHODS

Breast, lung, and ovarian tumor samples were analyzed for MPL expression by microarray and/or quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and for TPO-R protein expression by immunohistochemistry (IHC). Cell line proliferation assays were used to analyze the in vitro effect of eltrombopag on breast, lung, and ovarian tumor cell proliferation. The lung carcinoma cell lines were also analyzed for TPO-R protein expression by Western blot.

RESULTS

MPL mRNA was not detectable in 118 breast tumors and was detectable at only very low levels in 48% of 29 lung tumors studied by microarray analysis. By qRT-PCR, low but detectable levels of MPL mRNA were detectable in some normal (14-43%) and malignant (3-17%) breast, lung, and ovarian tissues. A comparison of MPL to EPOR, ERBB2, and IGF1R mRNA demonstrates that MPL mRNA levels were far lower than those of EPOR and ERBB2 mRNA in the same tissues. IHC analysis showed negligible TPO-R protein expression in tumor tissues, confirming mRNA analysis. Culture of breast, lung, and ovarian carcinoma cell lines showed no increase, and in fact, showed a decrease in proliferation following incubation with eltrombopag. Western blot analyses revealed no detectable TPO-R protein expression in the lung carcinoma cell lines.

CONCLUSIONS

Multiple analyses of breast, lung, and ovarian tumor samples and/or cell lines show no evidence of MPL mRNA or TPO-R protein expression. Eltrombopag does not stimulate growth of breast, lung, or ovarian tumor cell lines at doses likely to exert their actions on megakaryocytes and megakaryocyte precursors.

Q-TWiST analysis to estimate overall benefit for patients with metastatic renal cell carcinoma treated in a phase III trial of sunitinib vs interferon-α

Background:

In a randomised phase III trial of treatment-naive patients with metastatic renal cell carcinoma, sunitinib showed significant improvement in progression-free survival (PFS) compared with interferon (IFN)-α. We assessed between-treatment differences in overall benefit using a quality-adjusted Time Without Symptoms of disease progression or Toxicity of treatment (TWiST; Gelber and Goldhirsch) analysis.

Methods:

In this analysis, in which only grade 3/4 treatment-related toxicities were included, overall survival was partitioned into three health states: toxicity (time with toxicity after randomisation and before progression), time without symptoms of disease progression or toxicity, and time from progression until death. Between-treatment differences in the mean duration of each state were calculated. A threshold utility analysis was used to assess quality-adjusted TWiST (Q-TWiST) outcomes.

Results:

Q-TWiST scores showed that quality-adjusted survival time was greater with sunitinib than with IFN-α, even though certain grade 3/4 toxicities occurred more frequently with sunitinib. For both treatments, the mean number of days with toxicity was small compared with PFS. This effect was more pronounced with sunitinib in which time spent without progression or toxicity was 151 days greater than with IFN-α.

Conclusion:

Patients randomised to sunitinib had longer clinical benefit, defined as Q-TWiST scores, than patients randomised to IFN-α.

Quality-adjusted survival analysis of first-line treatment of hormone-receptor-positive HER2+ metastatic breast cancer with letrozole alone or in combination with lapatinib

AIM

Compare first-line lapatinib plus letrozole (L + Let) versus letrozole monotherapy (Let) in hormone-receptor-positive HER2 + metastatic breast cancer, employing Q-TWiST (quality-adjusted time without symptoms and toxicity) analysis to account for differences in progression times, with offsets for the impact of adverse events during the treatment period.

METHODS

The area under survival curves for each treatment group was partitioned into distinct health states of varying utility: toxicity (TOX), time without toxicity or disease progression (TWiST), and the period following disease progression until death or end of follow-up (REL). The utility-weighted sum of the mean health state durations was derived for each group. The threshold utility analysis evaluates how varying utility values across the states affects Q-TWiST differences between groups, although the method is limited by not varying utilities within each health state.

RESULTS

The primary analysis population was the HER2 + subgroup (n = 219). There was no significant difference between treatments in mean duration of grade 3/4 adverse events prior to progression (L + Let = 1.95 weeks; Let = 2.14 weeks; P = 0.90). Using utility weights of 0.5 for TOX and REL, L + Let was favored for quality-adjusted survival by 8.8 weeks (P = 0.09). The Q-TWiST difference between treatment groups ranged from 8 to 9.5 weeks, favoring combination therapy for all hypothetical utility levels, but none of the comparisons were statistically significant at P = 0.05.

CONCLUSIONS

No significant differences were found between L + Let versus Let in mean duration of severe adverse events. Quality-adjusted survival was favored for the combination treatment arm for all utility levels examined when toxicity was defined by grade 3/4 AEs, but differences between groups were not statistically significant.

Statistical aspects in comparative benefit-risk assessment: challenges and opportunities for pharmaceutical statisticians

Benefit-risk assessment is a fundamental element of drug development with the aim to strengthen decision making for the benefit of public health. Appropriate benefit-risk assessment can provide useful information for proactive intervention in health care settings, which could save lives, reduce litigation, improve patient safety and health care outcomes, and furthermore, lower overall health care costs. Recent development in this area presents challenges and opportunities to statisticians in the pharmaceutical industry. We review the development and examine statistical issues in comparative benefit-risk assessment. We argue that a structured benefit-risk assessment should be a multi-disciplinary effort involving experts in clinical science, safety assessment, decision science, health economics, epidemiology and statistics. Well planned and conducted analyses with clear consideration on benefit and risk are critical for appropriate benefit-risk assessment. Pharmaceutical statisticians should extend their knowledge to relevant areas such as pharmaco-epidemiology, decision analysis, modeling, and simulation to play an increasingly important role in comparative benefit-risk assessment.

A Q-TWiST analysis comparing panitumumab plus best supportive care (BSC) with BSC alone in patients with wild-type KRAS metastatic colorectal cancer

Background:

Panitumumab+best supportive care (BSC) significantly improved progression-free survival (PFS) vs BSC alone in patients with chemo-refractory wild-type KRAS metastatic colorectal cancer (mCRC). We applied the quality-adjusted time without symptoms of disease or toxicity (Q-TWiST) analysis to provide an integrated measure of clinical benefit, with the objective of comparing quality-adjusted survival between the two arms. As the trial design allowed patients on BSC alone to receive panitumumab after disease progression, which confounded overall survival (OS), the focus of this analysis was on PFS.

Methods:

For each treatment group, the time spent in the toxicity (grade 3 or 4 adverse events; TOX), time without symptoms of disease or toxicity (TWiST), and relapse (after disease progression; REL) states were estimated by the product-limit method, and adjusted using utility weights derived from patient-reported EuroQoL 5-dimensions measures. Sensitivity analyses were performed in which utility weights (varying from 0 to 1) were applied to time in the TOX and REL health states.

Results:

There was a significant difference between groups favouring panitumumab+BSC in quality-adjusted PFS (12.3 weeks vs 5.8 weeks, respectively, P<0.0001) and quality-adjusted OS (P=0.0303).

Conclusion:

In patients with chemo-refractory wild-type KRAS mCRC, panitumumab+BSC significantly improved quality-adjusted survival compared with BSC alone.

The cost-effectiveness of bortezomib in relapsed/refractory multiple myeloma: Swedish perspective

OBJECTIVES

To estimate the cost-effectiveness of bortezomib (BTZ) compared with dexamethasone (DEX) and lenalidomide plus dexamethasone (LEN/DEX) for the treatment of relapsed/refractory multiple myeloma in Sweden.

METHODS

We used partitioned survival analysis to assess survival data decomposed into three states: (i) alive before disease progression; (ii) alive after progression; and (iii) dead. The effects of treatment on time to progression and overall survival (OS) were obtained from published reports of the APEX, MM-009, and MM-010 randomized clinical trials. Costs included drug and administration costs, adverse events, treatment of relapses, and end-of-life costs. Utility estimates were derived from the literature.

RESULTS

BTZ mean OS was 57.4 months compared with 44.6 and 54.1 months for DEX and LEN/DEX, respectively. Mean lifetime direct medical costs per patient were approximately 2010 SEK 1,904,462, 1,278,854, and 2,450,588 for BTZ, DEX, and LEN/DEX, respectively. Mean incremental cost per quality-adjusted life-year of BTZ compared to DEX was 2010 SEK 902,874 (€95,073) (95% CI: 514,791, 962,416) and was dominant with respect to LEN/DEX.

CONCLUSION

BTZ and LEN/DEX are projected to prolong survival relative to DEX. From a Swedish perspective, BTZ is cost-effective compared to DEX and LEN/DEX.

Quality of life in hormone receptor-positive HER-2+ metastatic breast cancer patients during treatment with letrozole alone or in combination with lapatinib

This paper presents analyses evaluating quality of life in patients with hormone receptor–positive human epidermal growth factor receptor 2–positive tumors receiving letrozole alone or in combination with lapatinib in clinical trial EGF30008.

Background.

A phase III trial compared lapatinib plus letrozole (L + Let) with letrozole plus placebo (Let) as first-line therapy for hormone receptor (HR)⁺ metastatic breast cancer (MBC) patients. The primary endpoint of progression-free survival (PFS) in patients whose tumors were human epidermal growth factor receptor (HER)-2⁺ was significantly longer for L + Let than for Let (8.2 months versus 3 months; p = .019). This analysis focuses on quality of life (QOL) in the HER-2⁺ population.

Methods.

QOL was assessed at screening, every 12 weeks, and at withdrawal using the Functional Assessment of Cancer Therapy–Breast (FACT–B). Changes from baseline were analyzed and the proportions of patients achieving minimally important differences in QOL scores were compared. Additional exploratory analyses evaluated how QOL changes reflected tumor progression status.

Results.

Among the 1,286 patients randomized, 219 had HER-2⁺ tumors. Baseline QOL scores were comparable in the two arms. Mean changes in QOL scores were generally stable over time for patients who stayed on study. The average change from baseline on the FACT-B total score in both arms was positive at all scheduled visits through week 48. There was no significant difference between the two treatment arms in the percentage of QOL responders.

Conclusion.

The addition of lapatinib to letrozole led to a significantly longer PFS interval while maintaining QOL during treatment, when compared with letrozole alone, thus confirming the clinical benefit of the combination therapy in the HR⁺ HER-2⁺ MBC patient population. This all oral regimen provides an effective option in this patient population, delaying the need for chemotherapy and its accompanying side effects.

A review of quantitative risk-benefit methodologies for assessing drug safety and efficacy-report of the ISPOR risk-benefit management working group

OBJECTIVE

Although regulatory authorities evaluate the risks and benefits of any new drug therapy during the new drug-approval process, quantitative risk-benefit assessment (RBA) is not typically performed, nor is it presented in a consistent and integrated framework when it is used. Our purpose is to identify and describe published quantitative RBA methods for pharmaceuticals.

METHODS

Using MEDLINE and other Internet-based search engines, a systematic literature review was performed to identify quantitative methodologies for RBA. These distinct RBA approaches were summarized to highlight the implications of their differences for the pharmaceutical industry and regulatory agencies.

RESULTS

Theoretical models, parameters, and key features were reviewed and compared for the 12 quantitative RBA methods identified in the literature, including the Quantitative Framework for Risk and Benefit Assessment, benefit-less-risk analysis, the quality-adjusted time without symptoms and toxicity, number needed to treat (NNT), and number needed to harm and their relative-value-adjusted versions, minimum clinical efficacy, incremental net health benefit, the risk-benefit plane (RBP), the probabilistic simulation method, multicriteria decision analysis (MCDA), the risk-benefit contour (RBC), and the stated preference method (SPM). Whereas some approaches (e.g., NNT) rely on subjective weighting schemes or nonstatistical assessments, other methods (e.g., RBP, MCDA, RBC, and SPM) assess joint distributions of benefit and risk.

CONCLUSIONS

Several quantitative RBA methods are available that could be used to help lessen concern over subjective drug assessments and to help guide authorities toward more objective and transparent decision-making. When evaluating a new drug therapy, we recommend the use of multiple RBA approaches across different therapeutic indications and treatment populations in order to bound the risk-benefit profile.

Impact of lapatinib monotherapy on QOL and pain symptoms in patients with HER2+ relapsed or refractory inflammatory breast cancer

OBJECTIVE

EGF103009 (ClinicalTrials.gov identifier: NCT00105950) was a phase 2, open-label, multicenter study that showed lapatinib monotherapy to be clinically active in women with relapsed or refractory HER2+ (ErbB2+) inflammatory breast cancer that progressed following prior therapy with anthracyclines, taxanes, and trastuzumab. The objective of the present study was to assess the impact of lapatinib on quality of life (QOL) and pain symptoms in these patients.

RESEARCH DESIGN AND METHODS

QOL and pain assessments were added during a study amendment and hence only 33 of 126 HER2+ patients were available for baseline assessment. QOL and pain were assessed using the EORTC QLQ-C30 and Brief Pain Inventory-Short Form (BPI-SF) questionnaires, respectively. Both questionnaires were completed at baseline and every 4 weeks thereafter. Change from baseline in QOL and pain scores were summarized by visit. In a post hoc analysis, scores were compared between patients with different clinical response status.

RESULTS

Over 60% of the 33 HER2+ patients with the baseline assessments completed the first three postbaseline assessments (week 4, n = 26; week 8, n = 21; week 12, n = 20). At week 8, improvement from baseline in mean EORTC QLQ-C30 scores was observed for global QOL (delta = 14.5; 95% CI: 4.0, 25.0), role functioning (delta = 15; 95% CI: 0.9, 29.1), social functioning (delta = 14.9; 95% CI: -0.5, 30.3), and physical functioning subscales (delta = 9.0; 95% CI: 1.2, 16.8). All symptom scales (except diarrhea) improved from baseline at most scheduled visits during the 20-week follow-up period. Mean scores for all four BPI-SF summary pain scores at week 8 suggested improvement in pain severity and pain interference. Clinical responders had improved scores on most aspects of QOL, compared with declining scores among nonresponders to treatment.

CONCLUSIONS

The QOL improvement among the small number of patients with QOL data indicates that lapatinib monotherapy may improve level of functioning/QOL and provide relief from symptoms, including pain, in the short term. These QOL benefits add to the clinical improvement associated with lapatinib therapy in heavily pretreated patients with an aggressive form of breast cancer.

Quality-of-life and quality-adjusted survival (Q-TWiST) in patients receiving lapatinib in combination with paclitaxel as first-line treatment for metastatic breast cancer

BACKGROUND

In a phase 3 randomized, multicenter, double-blind, placebo-controlled study, first-line therapy with lapatinib plus paclitaxel significantly improved clinical outcomes based on a pre-planned analysis of ErbB2+ metastatic breast cancer patients (GSK Study #EGF30001; ClinicalTrials.gov identifier: NCT00075270). Patients with ErbB2- or untested did not significantly benefit. This article focuses on the quality of life (QOL) and quality-adjusted survival outcomes (Q-TWiST) in the study.

METHODS

QOL was assessed using the Functional Assessment of Cancer Therapy-Breast (FACT-B). Changes from baseline were analyzed using ANCOVAs, repeated measures and pattern mixture modeling. The Q-TWiST method was used to examine the trade-off between toxicities and delayed progression.

RESULTS

The study included 579 subjects, of whom 86 were ErbB2+. In the ITT population, no significant differences in QOL or Q-TWiST scores were observed. In the ErbB2+ subgroup, the lapatinib plus paclitaxel (L + P) arm demonstrated stable FACT-B scores over the first year, while average scores for patients on P + placebo (P + pla) monotherapy decreased (change from baseline: L + P, p = 0.99; P + pla, p = 0.01). Clinically meaningful differences were observed between treatment arms on the FACT-B, Trial Outcome Index and breast cancer subscale scores. Pattern mixture models suggested more QOL differentiation between treatments among patients who progressed or withdrew early. Q-TWiST differences between the arms in the ErbB2+ subgroup ranged from 2 to 15 weeks with an L + P advantage across all utility weight combinations.

CONCLUSIONS

In the ITT population, results provide no evidence of QOL differences between treatment groups. In a small, prospectively-defined subgroup of ErbB2+ patients, L + P resulted in more stable QOL and more quality-adjusted survival than paclitaxel monotherapy, representing clinically important differences between treatments.

Lapatinib: a review of its use in the treatment of HER2-overexpressing, trastuzumab-refractory, advanced or metastatic breast cancer

Lapatinib (Tyverb, Tykerb) is an orally active, small molecule, reversible, dual tyrosine kinase inhibitor of human epidermal growth factor receptor type 1 (HER1) and type 2 (HER2). In the EU, lapatinib in combination with capecitabine is indicated for the treatment of women with HER2-overexpressing, advanced or metastatic breast cancer that has progressed after treatment with regimens that include anthracyclines, taxanes and, in the metastatic setting, trastuzumab. The orally administered combination of lapatinib and capecitabine was a more effective treatment than capecitabine alone, and was a generally well tolerated, conveniently administered combination for women with trastuzumab-refractory, HER2-positive advanced or metastatic breast cancer in a clinical trial. Lapatinib combined with capecitabine provides an effective therapeutic option for a group of patients who currently have few treatment choices.

Q-TWiST analysis of patients receiving temsirolimus or interferon alpha for treatment of advanced renal cell carcinoma

BACKGROUND AND OBJECTIVES

For patients with advanced cancers, it is important that treatment improves the quality as well as the quantity of survival. This quality-adjusted time without symptoms of progression or toxicity (Q-TWiST) analysis provides a combined measure of both the overall survival interval and the quality of survival for patients with advanced renal cell carcinoma (RCC) receiving temsirolimus, interferon (IFN)-alpha or the combination of these agents, using data from a phase III clinical trial.

METHODS

Overall survival was partitioned into three distinct health states: time with serious toxicity (TOX), time after progression (REL) and time without symptoms of progression or toxicity (TWiST). Health states were quality weighted by patient-reported EQ-5D measures collected while receiving treatment.

RESULTS

All 626 patients from the trial were included in computation of health-state durations. EQ-5D questionnaires were obtained from 260 patients upon progression and from 230 after a grade 3 or 4 adverse event, and from 278 patients in the TWiST state. Patients receiving temsirolimus had 38% longer TWiST than those receiving IFNalpha (6.5 vs 4.7 months, respectively; p = 0.0005). Patients receiving temsirolimus had 25% longer quality-adjusted survival in terms of Q-TWiST than those receiving IFNalpha (7.0 vs 5.6 months, respectively; p = 0.0015). Differences between the combination (temsirolimus + IFNalpha) and IFNalpha groups were not statistically significant. Threshold utility analysis indicated that temsirolimus was the preferred alternative for all possible utility weights for REL and TOX health states.

CONCLUSION

Temsirolimus resulted in significantly longer Q-TWiST (quality-adjusted survival) in patients with advanced RCC than IFNalpha therapy.