Hemophilia Burden of Disease: A Systematic Review of the Cost-Utility Literature for Hemophilia

BACKGROUND

Prophylaxis with clotting factor replacement products is recommended by the Medical and Scientific Advisory Council of the National Hemophilia Foundation as the optimal therapy for the prevention of bleeding episodes in individuals with severe hemophilia A or B (< 1 IU per dL endogenous factor VIII or factor IX activity, respectively). Prophylaxis is associated with an improved health-related quality of life and has been shown to be cost-effective compared with on-demand therapy. However, the overall cost of treatment remains high, particularly among patients with a greater propensity to bleed. The overall value of hemophilia treatments and their associated benefits, measured in quality-adjusted life-years (QALYs), and dollar costs compared with other interventions can be evaluated through the use of cost-utility analyses (CUAs). Previous CUA studies in hemophilia have focused primarily on patients with more severe forms of hemophilia and on prophylaxis compared with on-demand treatment. However, to our knowledge, no studies to date have utilized QALYs as a standardized outcome measure to systematically evaluate the relative cost-effectiveness of current hemophilia treatment options.

OBJECTIVE

To systematically review the CUA literature of hemophilia treatments and demonstrate the challenges in producing cost-utility evidence compared with other rare diseases.

METHODS

We conducted a systematic literature review using the Tufts Medical Center Cost-Effectiveness Analysis Registry and the National Health Service Economic Evaluation Database for English-language CUAs published from 2000 through 2015 with the search terms hemophilia, haemophilia, factor VIII, or factor IX. Two trained reviewers independently reviewed every study to extract relevant data. Incremental cost-effectiveness ratios were converted to 2014 U.S. dollars using exchange rates for currency conversion and the Consumer Price Index to adjust for inflation.

RESULTS

Our search yielded 52 studies, 11 of which met our inclusion criteria. The cost-effectiveness of hemophilia treatments varied widely based on variations in the study designs, including differences in time horizon, discount rates, and medical interventions.

CONCLUSIONS

We found the cost-effectiveness of hemophilia treatments to be broadly comparable to that of other orphan drugs. Improved standardization of future CUA studies will be important for further evaluation of the cost-effectiveness of hemophilia treatments.

DISCLOSURES

This research was funded by Biogen, which provided an unrestricted research grant to the Center for the Evaluation of Value and Risk in Health at Tufts Medical Center. Biogen and Sobi reviewed and provided feedback on the manuscript. The authors had full editorial control of the manuscript and provided final approval of all content. The authors report no conflict of interest regarding the material discussed in this article. Neumann and Chambers are employed at the Center for the Evaluation of Value and Risk in Health at Tufts Medical Center. Thorat was an employee of Center for Evaluation Value and Risk in Health, Tufts Medical Center when the analyses were carried out. Chambers has participated on advisory boards for Sanofi and Astellas Pharma.

Is the EQ-5D suitable for use in oncology? An overview of the literature and recent developments

The European Quality of Life-5 Dimensions (EQ-5D) questionnaire is widely used in oncology to generate quality of life weights (utilities). The typical purpose is to inform health economic evaluation studies. The EQ-5D is generally suitable for this purpose; it has shown a reasonable degree of reliability, content validity, construct validity and responsiveness in the majority of the available studies. In situations of doubt, combination with other quality-of-life instruments may be an option. The authors expect that the five-level version of the EQ-5D will gradually replace the three-level version, due to reduced ceiling effects and more appropriate responsiveness. Further research should address the benefits achievable through additional dimensions or patient-based valuation, and the validity of EQ-5D versions for proxy respondents.

When is Genomic Testing Cost-Effective? Testing for Lynch Syndrome in Patients with Newly-Diagnosed Colorectal Cancer and Their Relatives

Varying estimates of the cost-effectiveness of genomic testing applications can reflect differences in study questions, settings, methods and assumptions. This review compares recently published cost-effectiveness analyses of testing strategies for Lynch Syndrome (LS) in tumors from patients newly diagnosed with colorectal cancer (CRC) for either all adult patients or patients up to age 70 along with cascade testing of relatives of probands. Seven studies published from 2010 through 2015 were identified and summarized. Five studies analyzed the universal offer of testing to adult patients with CRC and two others analyzed testing patients up to age 70; all except one reported incremental cost-effectiveness ratios (ICERs) < $ 100,000 per life-year or quality-adjusted life-year gained. Three studies found lower ICERs for selective testing strategies using family history-based predictive models compared with universal testing. However, those calculations were based on estimates of sensitivity of predictive models derived from research studies, and it is unclear how sensitive such models are in routine clinical practice. Key model parameters that are influential in ICER estimates included 1) the number of first-degree relatives tested per proband identified with LS and 2) the cost of gene sequencing. Others include the frequency of intensive colonoscopic surveillance, the cost of colonoscopy, and the inclusion of extracolonic surveillance and prevention options.

A cost-utility analysis of NRG Oncology/Gynecologic Oncology Group Protocol 218: incorporating prospectively collected quality-of-life scores in an economic model of treatment of ovarian cancer

OBJECTIVE

To estimate quality-of-life (QOL)-adjusted cost-utility with addition of bevacizumab (B) to intravenous paclitaxel/carboplatin (PC) for primary treatment of advanced-stage epithelial ovarian cancer.

METHODS

A modified Markov state transition model of 3 regimens evaluated in GOG 218 (PC, PC+concurrent B [PCB], and PCB+maintenance B [PCB+B]) was populated by prospectively collected survival, adverse event, and QOL data from GOG 218. Progression-free survival (PFS) and overall survival (OS) were modeled using primary event data. Costs of grade 4 hypertension, grade 3-5 bowel events, and growth factor support were incorporated. QOL scores were converted to utilities and incorporated into the model. Monte Carlo probabilistic sensitivity analysis was performed to account for uncertainty in estimates.

RESULTS

PC was the least expensive ($4044) and least effective (mean 1.1 quality-adjusted progression-free years [QA-PFY]) regimen. PCB ($43,703 and 1.13 QA-PFY) was dominated by a combination of PC and PCB+B. PCB+B ($122,700 and 1.25 QA-PFY) was the most expensive regimen with an incremental cost-effectiveness ratio of $792,380/QA-PFY compared to PC. In a model not incorporating QOL, the incremental cost-effectiveness ratio (ICER) of PCB+B was $632,571/PFY compared to PC.

CONCLUSIONS

In this cost-utility model, incorporation of QOL into an analysis of GOG 218 led to less favorable ICER (by >$150,000/QA-PFY) in regimens containing B compared with those that do not include B. Continued investigation of populations with ovarian cancer in whom the efficacy of treatment with bevacizumab is expected to be increased (or in whom QOL is expected to increase with use) is critical.

Predicting health utilities for children with autism spectrum disorders

Comparative effectiveness of interventions for children with autism spectrum disorders (ASDs) that incorporates costs is lacking due to the scarcity of information on health utility scores or preference-weighted outcomes typically used for calculating quality-adjusted life years (QALYs). This study created algorithms for mapping clinical and behavioral measures for children with ASDs to health utility scores. The algorithms could be useful for estimating the value of different interventions and treatments used in the care of children with ASDs. Participants were recruited from two Autism Treatment Network sites. Health utility data based on the Health Utilities Index Mark 3 (HUI3) for the child were obtained from the primary caregiver (proxy-reported) through a survey (N = 224). During the initial clinic visit, proxy-reported measures of the Child Behavior Checklist, Vineland II Adaptive Behavior Scales, and the Pediatric Quality of Life Inventory 4.0 (start measures) were obtained and then merged with the survey data. Nine mapping algorithms were developed using the HUI3 scores as dependent variables in ordinary least squares regressions along with the start measures, the Autism Diagnostic Observation Schedule, to measure severity, child age, and cognitive ability as independent predictors. In-sample cross-validation was conducted to evaluate predictive accuracy. Multiple imputation techniques were used for missing data. The average age for children with ASDs in this study was 8.4 (standard deviation = 3.5) years. Almost half of the children (47%) had cognitive impairment (IQ ≤ 70). Total scores for all of the outcome measures were significantly associated with the HUI3 score. The algorithms can be applied to clinical studies containing start measures of children with ASDs to predict QALYs gained from interventions.