<p>The impact of increased post-progression survival on the cost-effectiveness of interventions in oncology</p>

Abstract

Purpose: Cost-effectiveness analyses (CEA) of new technologies typically include “background” costs (eg, all “related” health care costs other than the specific technology under evaluation) as well as drug costs. In oncology, these are often expensive. The marginal cost-effectiveness ratio (ie, the extra costs and QALYs associated with each extra period of survival) calculates the ratio of background costs to QALYs during post-progression. With high background costs, the incremental cost-effectiveness ratio (ICER) can become less favorable as survival increases and the ICER moves closer to the marginal cost-effectiveness ratio, making cost-effectiveness prohibitive. This study assessed different methods to determine whether high ICERs are caused by high drug costs, high “background costs” or a combination of both and how different approaches can alter the impact of background costs on the ICER where the marginal cost-effectiveness ratio is close to, or above, the cost-effectiveness threshold. Methods: The National Institute for Health and Care Excellence oncology technology appraisals published or updated between October 2012 and October 2017 were reviewed. A case study was selected, and the CEA was replicated. Three modeling approaches were tested on the case study model. Results: Applying one-off “transition” costs during post-progression reduced the ongoing “incremental” costs of survival, which meant that the marginal cost-effectiveness ratio was substantially reduced and problems associated with additional survival were less likely to impact the ICER. Similarly, the use of two methods of additional utility weighting for end-of-life cases meant that the marginal cost-effectiveness ratio was reduced proportionally, again lessening the impact of increased survival. Conclusion: High ICERs can be caused by factors other than the cost of the drug being assessed. The economic models should be correct and valid, reflecting the true nature of marginal survival. Further research is needed to assess how alternative approaches to the measurement and application of background costs and benefits may provide an accurate assessment of the incremental benefits of life-extending oncology drugs. If marginal survival costs are incorrectly calculated (ie, by summing total post-progressed costs and dividing by the number of baseline months in that state), then the costs of marginal survival are likely to be overstated in economic models.

Methodological challenges and potential solutions for economic evaluations of palliative and end-of-life care: A systematic review

“…The majority were published in the past 10 years ( N = 59 (70%)). The largest group of first authors (41%) was affiliated with institutions in the UK, 15,16,20,22,26,34 –61 followed by the USA (13%). 62 –71 Study types and their focus varied widely, including systematic reviews and meta-analyses, 17,26,41,52 –54,72,73 qualitative studies 35,36,40,44,49,50,51,58,74 and studies describing, for example, the development and/or concept of an outcome measure, testing its validity.…”

“…In total, we identified challenges that can be grouped into nine themes, with most of the studies relating to three of them: ambiguity in the selection of outcomes, 16,17,20 –22,26,34 –50,62,63,72,74–88 , non-standardised measurement and valuation of costs, 15,17,26,40 –42,47,51 –57,61,64,65,73,85,89 –93 and narrow costing perspective app-lied. 17,20,…”

“…65 Nevertheless, distinguishing these costs from other health care costs, such as managing adverse events and providing follow-on treatments, can still be difficult, especially in severe health states characterised by natural deterioration. 61 Recommendations. Valid comparisons across studies, countries and health care systems, require standardised, locally validated and contextually relevant cost items 16,41,73 and definitions.…”

“…Additionally, natural health status deterioration in advanced disease stages may result in high resource use and costs unrelated to the intervention. 61 Our systematic review fills an important gap in the literature by offering an initial overview of methodological considerations in economic evaluations for palliative and end-of-life care. Our findings will inform the economic evaluation of palliative and end-of-life care interventions in the iLIVE project, 27 guide future evaluations and promote transparency and comparability.…”

A Cost-Effectiveness Framework for Amyotrophic Lateral Sclerosis, Applied to Riluzole

“…Cost categorization into RCs and TCs is typically not described with ALS and is uncommonly reported in other conditions. 45 Distinguishing RC and TC can be difficult. For instance, in the case of ALS, it is expected that hospitalization in late stages for respiratory symptoms results in the establishment of a home respiratory care or palliation plan that would prevent future hospital admissions, but that is not guaranteed; categorizing hospitalization as an RC instead, at the rate of $1903/month 8 inflates model I ICER to $110 847.…”