Cost-effectiveness of left atrial appendage occlusion during cardiac surgery in France: An economic evaluation based on the LAAOS III study.

OBJECTIVES: Left atrial appendage occlusion during cardiac surgery is a therapeutic option for stroke prevention in patients with atrial fibrillation. The effectiveness and safety of left atrial appendage occlusion have been evaluated in several studies, including the LAAOS-III trial. While these studies have demonstrated efficacy and safety, the long-term economic impact of this surgical technique has not yet been assessed. Here, we aimed to evaluate the cost-effectiveness and cost-utility of left atrial appendage occlusion during cardiac surgery over a long-term time horizon. METHODS: Our study was based on a model representing an hypothetical cohort with the same characteristics as LAAOS-III trial patients. We modelled the incidence of ischemic strokes and systemic embolisms in each intervention arm: "occlusion" and "no-occlusion," using a one-month cycle length with a 20-year time horizon. Regarding occlusion devices, sutures, staples, or an approved surgical occlusion device (AtriClip™-AtriCure, Ohio, USA) could be used. RESULTS: Our model generated an average cost savings of 607 euros per patient and an incremental gain of 0.062 quality-adjusted life years (QALYs), resulting an incremental cost-utility ratio (ICUR) of €-9,775/QALY. The scenario analysis in which occlusion was systematically performed using the AtriClip™ device generated an ICUR of €3,952/QALY gained. CONCLUSIONS: In the base-case analysis, the strategy proved to be more effective and less costly, confirming left atrial appendage occlusion during cardiac surgery as an economically dominant strategy. The scenario analysis also appeared cost-effective, although it did not result in cost savings. This study provides a new perspective on the assessment of the cost-effectiveness of these techniques.

Potential impact on cost-effectiveness estimates of using immature survival data: a case study based on transcatheter edge-to-edge repair (TEER) used for patients with severe mitral regurgitation at high surgical risk.

OBJECTIVE: To review the survival modelling used in cost-effectiveness studies evaluating an interventional procedure and to discuss implications for decision-makers. DESIGN: A case study of three economic evaluations that each used immature data from the EVEREST II High Surgical Risk (HSR) Study of transcatheter edge-to-edge repair (TEER) for patients with severe mitral regurgitation (MR) who were at high risk of surgery. SETTING: Estimation of patient survival in cost-effectiveness studies. PARTICIPANTS: The EVEREST II HSR Study included 78 patients who had TEER of the mitral valve using the MitraClip device and a retrospectively identified control group of 36 patients who received medical management and were followed up for 12 months. Observed survival (TEER arm only) was updated at 5 years. RESULTS: Two studies used 12-month observed mortality from EVEREST II HSR to model survival over lifetime horizons. Observed and modelled survival were associated with considerable uncertainty due to short follow-up and small numbers of participants. Modelling control patients' survival required an approximate 10-fold extrapolation based on 12-month observation of only 38 patients. Observed 5-year survival in the TEER group differed from that less mature follow-up suggesting that survival modelling based on shorter follow-up was unsatisfactory. No public domain data for the control group are available beyond 12-month follow-up so meaningful estimates using mature data for both arms are currently not possible. A third study developed survival models using incompletely reported transitions between MR grades in EVEREST II HSR and mortality rates observed for different MR grades derived from a study in an unrelated population. CONCLUSIONS: Modelling survival in such small samples followed up for only 12 months is associated with great uncertainty, and cost-effectiveness results based on these analyses should be viewed as premature and used cautiously in reimbursement decisions.

Impact of updated trial data on the cost-effectiveness of percutaneous mitral repair.

When updated clinical trial data becomes available reassessing the cost-effectiveness of technologies may modify estimates and influence decision-making. We investigated the impact of updated trial outcomes on the cost-effectiveness of percutaneous mitral repair (PR) for secondary mitral regurgitation. We updated our previous three-state time-varying Markov model to assess the cost-effectiveness of PR + guideline directed medical treatment (GDMT) versus GDMT alone. Key clinical inputs (overall survival (OS) and heart failure hospitalisations (HFH)) were obtained using the 3-year trial findings from the COAPT (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy) RCT. We calculated incremental cost-effectiveness ratios (ICER) and report how these differ between analyses based on early (2-year) and updated (3-year) evidence. Updated trial data showed an increase in mortality in the intervention arm between two and three years follow-up that was not seen in the control arm. Deterministic and multivariate cost-effectiveness modelling yielded incremental cost effectiveness ratios ICERs of €38,123 and €31,227 /QALY. Compared to our 2-year based estimate (€21,918 / QALY) these results imply an approximate 1.5-fold increase in ICER. The availability of updated survival analyses from the COAPT pivotal trial suggests previous estimates based on 2-year trial findings were over optimistic for the intervention.

Real-world data and evidence in health technology assessment: When are they complementary, substitutes, or the only sources of data compared to clinical trials?

Within the life-cycle assessment of health technologies, real-world data (RWD) have until now been of secondary importance to clinical trial data. The availability of massive, better quality RWD, particularly with the emergence of connected devices, the improvement of methods for characterizing populations, make it possible to have a better insight into the effects of treatment, sometimes on a national scale the importance of RWD is likely to progress in the eyes of health technology assessors, going from being traditionally complementary to possibly replacing clinical trial data. This is the fundamental question that the round table, involving experts from the academic and/or hospital, institutional, and industrial worlds, set out to answer. This work served first to establish the current role of RWD in health technology assessment, by distinguishing the main purposes of RWD, the timing of the evaluation in relation to the life cycle of the technology, and then according to the party commissioning or receiving the outcomes of RWD-based studies. Secondly, the round table proposed six general recommendations for more intensive and decisive use of RWD in the assessment and decision-making process.

Is the assumption of waning of treatment effect applied consistently across NICE technology appraisals? A case-study focusing on disease-modifying therapies for treatment of multiple sclerosis.

OBJECTIVES: Whether the effects of therapies may wane over time is a matter of debate, especially when considering their long-term cost-effectiveness. Here, we examined how the assumption of the waning of treatment effect was applied across the National Institute for Health and Care Excellence (NICE) appraisals for disease-modifying therapies (DMTs) used in multiple sclerosis. METHODS: We undertook a document analysis following a search of the NICE website. The inclusion criteria of the study were as follows: all publicly available documents related to completed appraisals for DMTs (period: January 2000 to July 2021). The exclusion criteria of the study were as follows: all documents that did not meet the inclusion criteria, especially pertaining to drugs used in other disease areas. We extracted information about the waning of treatment effect assumption as considered by companies, assessment groups, and appraisal committees, and we analyzed trends over time. RESULTS: We reviewed fifteen appraisals that reported guidance on sixteen DMTs. Irrespective of the drugs' mechanism of action or their pharmaceutical nature, there was substantial variation in the modalities when the assumption of waning was implemented. We noted the recent preference to use all-cause discontinuation as a proxy. This heterogeneity did not appear to affect acceptance of the DMTs (all but one were recommended for use across the National Health System (NHS)). CONCLUSIONS: Modeling the long-term effect of therapies is challenging, especially given the limited follow-up duration of related trials. This generates recurrent debates on the presence of waning of treatment efficacy and heterogeneity across appraisals. More refined recommendations obtained by consensus among stakeholders could help to achieve greater consistency in decision making.

Percutaneous mitral valve repair in severe secondary mitral regurgitation: Analysis of index hospitalization and economic evaluation based on the MITRA-FR trial.

BACKGROUND: Percutaneous mitral valve repair (pMVR) is reimbursed in France for severe secondary mitral regurgitation (SMR), but French data regarding the hospitalization index stay are lacking. AIMS: Our objectives were to describe the index hospitalization stay and to evaluate the cost of hospital stay for pMVR used in SMR. METHODS: A secondary evaluation based on patients who were randomized to the intervention group of the MITRA-FR study was undertaken. The economic evaluation was conducted according to the French hospital perspective. Medical resource use was estimated using specific data collected from patients enrolled in the MITRA-FR study and non-specific data from national statistics. RESULTS: The population was represented by 144 patients who underwent pMVR at 33 French centres. There was a mean±standard deviation of 7.9±1.5 hospital staff during procedures. The mean procedure duration was 154±68 minutes and increased with the number of implanted clips. Median total length of stay was 8 days. The occurrence of a serious adverse event was not associated with an increased risk of admission to the critical care unit, but was associated with an increased length of stay. The mean total cost was 28,025±3424€, which includes 21,547€ for the cost of medical devices used during pMVR and 6478±3424€ for other costs. CONCLUSION: The cost of pMVR is substantial for patients with SMR, which advocates for further efforts to identify the patients with SMR who are likely to derive a clear clinical benefit from the procedure.

A comparison of published time invariant Markov models with Partitioned Survival models for cost effectiveness estimation; three case studies of treatments for glioblastoma multiforme.

BACKGROUND: Cost-effectiveness analyses of treatments for glioblastoma multiforme (GBM) have mostly used state transition Markov models with time invariant transition probabilities (TIMMs). In three case studies of GBM treatments, we compared Partitioned Survival model (PSM) results with published outputs from TIMMs. METHODS: PSMs used the same RCT data sources, utility values, time horizons, cycle times and annual discounting used in published TIMMs. Reported overall survival and progression-free survival plots were digitised and fitted with a range of parametric models. Economic model outputs were generated in the same form as reported for the TIMMs. PSM output uncertainty was explored in univariate and in multivariate sensitivity analyses. RESULTS: PSMs generated incremental cost-effectiveness ratios that were different to the published TIMMs. The magnitude of difference was substantial in two cases. The PSMs were reasonably robust and in sensitivity analyses were sensitive to variations in the same model inputs as were the TIMMs. When compared to the RCT data, the TIMMs tended to generate underestimates of the likely overall survival gain. TIMM estimates for depletion of individuals from the stable disease state and for accumulation in the dead state had relatively poor resemblance to the source RCT data. CONCLUSION: TIMMs delivered different cost-effectiveness estimates to PSMs; in two cases, TIMMs produced substantially lower ICER values than PSMs. Model output differences appear attributable to less realistic cost-and-benefit estimates generated in TIMMs due to rapid depletion from the stable disease state and/or accumulation in the dead state.