Cost-effectiveness analysis of selexipag for the combined treatment of pulmonary arterial hypertension

Objective: Adding selexipag to the combined treatment of endothelin receptor antagonists (ERA) and phosphodiesterase 5 inhibitor (PDE5i) reduces the risk of clinical worsening events in patients with pulmonary arterial hypertension (PAH) but at a considerably higher cost. This study evaluated the cost-effectiveness of adding selexipag to the combined treatment of ERA and PDE5i in patients with PAH from a Chinese healthcare system perspective. Methods: A Markov model was developed to assess costs and quality-adjusted life years (QALYs) of macitentan + tadalafil + selexipag vs. macitentan + tadalafil for the treatment of PAH. Markov states included WHO Functional Class (FC) (I-IV) and death. Transition probabilities were based on data from the TRITON trial. Mortality rates, costs, and utilities were obtained from published literature and public databases. Results: In the base case analysis, compared with macitentan + tadalafil, selexipag + macitentan + tadalafil increased costs ($357,807.588 vs. $116,534.543, respectively) and QALYs (7.234 QALYs vs. 6.666 QALYs, respectively). The resulting incremental cost-effectiveness ratio was $424,746.070 per QALY, which was higher than the willingness-to-pay (WTP) of $38,223.339 per QALY. The results were most sensitive to HR for mortality of patients with FC IV relative to the general population, discount rate, and the cost of selexipag. The probability was greater than 50% for the selexipag + macitentan + tadalafil only if the WTP was more significant than $426,019.200 per QALY. Conclusion: In China, adding selexipag may not be cost-effective for patients with PAH who failed to control their condition after combined treatment of ERA and PDE5i. Results of the analysis can aid discussions on the value and position of selexipag for the combined treatment of PAH.

Economic evaluation of bailing capsules for patients with diabetic nephropathy in China

Background: Diabetic nephropathy is a major microvascular complication and the main cause of end-stage renal disease in diabetic patients. The therapeutic effects of Bailing capsules for diabetic nephropathy have already been demonstrated; however, the cost-effectiveness of Bailing capsules remains controversial. This study aimed to evaluate the cost-effectiveness of Bailing capsules combined with Western medicine compared with Western medicine alone in diabetic nephropathy from a Chinese healthcare system perspective. Methods: A Markov model was established to simulate the disease process of patients over a 20-year period. Clinical efficacy data were obtained from a meta-analysis, and transition probability was estimated based on microsimulation. Direct costs and utility values were collected from the Chinese Drug Bidding Database (https://www.shuju.menet.com.cn) and published literature. The incremental cost-effectiveness ratio (ICER) was measured, and one-way and probabilistic sensitivity analyses were performed to observe model stability. Results: A total of 34 randomized controlled trials involving 3,444 patients with diabetic nephropathy were selected for the meta-analysis. Compared to Western medicine alone, the addition of Bailing capsules resulted in an increase of 0.39 quality-adjusted life-years (QALYs) and additional costs of Chinese Yuan (CNY) 24,721, yielding an ICER of CNY 63,001 per QALY gained. The ICER was lower than the threshold of willingness-to-pay of CNY 80,976 (The GDP per Capita in China). The reliability and stability of the results were confirmed by the sensitivity analysis. Conclusion: We found that Bailing capsules may be a cost-effective treatment choice for patients with diabetic nephropathy in the Chinese population.

Cost-effectiveness of a new ACI technique for the treatment of articular cartilage defects of the knee compared to regularly used ACI technique and microfracture

AIMS

For patients with cartilage defects of the knee, a new biocompatible and in situ cross-linkable albumin-hyaluronan-based hydrogel has been developed for matrix-associated autologous chondrocyte implantation (M-ACI) - NOVOCART® Inject plus (NInject)1. We aimed to estimate the potential cost-effectiveness of NInject, that is not available on the market, yet compared to spheroids of human autologous matrix-associated chondrocytes (Spherox^®)2 and microfracture.

MATERIALS AND METHODS

An early Markov model was developed to estimate the cost-effectiveness in the United Kingdom (UK) from the payer perspective. Transition probabilities, response rates, utility values and costs were derived from literature. Since NInject has not yet been launched and no prices are available, its costs were assumed equal to those of Spherox^®. Cycle length was set at one year and the time horizon chosen was notional patients' remaining lifetime. Model robustness was evaluated with deterministic and probabilistic sensitivity analyses (DSA; PSA) and value of information (VOI) analysis. The Markov model was built using TreeAge Pro Healthcare.

RESULTS

NInject was cost-effective compared to microfracture (ICER: ₤5,147) while Spherox® was extendedly dominated. In sensitivity analyses, the ICER exceeded conventional WTP threshold of ₤20,000 only when the utility value after successful first treatment with NInject was decreased by 20% (ICER: ₤69,620). PSA corroborated the cost-effectiveness findings of NInject, compared to both alternatives, with probabilities of 60% of NInject undercutting the aforementioned WTP threshold and being the most cost-effective alternative. The VOIA revealed that obtaining additional evidence on the new technology will likely not be cost-effective for the UK National Health Service.

LIMITATIONS AND CONCLUSION

This early Markov model showed that NInject is cost-effective for the treatment of articular cartilage defects in the knee, compared to Spherox and microfracture. However, as the final price of NInject has yet to be determined, the cost-effectiveness analysis performed in this study is provisional, assuming equal prices for NInject and Spherox.

Presumptive treatment or serological screening for schistosomiasis in migrants from Sub-Saharan Africa could save both lives and money for the Italian National Health System: results of an economic evaluation

BACKGROUND

Schistosomiasis can lead to severe irreversible complications and death if left untreated. Italian and European guidelines recommend serological screening for this infection in migrants from Sub-Saharan Africa (SSA). However, studies on clinical and economic impact of this strategy in the Italian and European settings are lacking. This study aims to compare benefits and costs of different strategies to manage schistosomiasis in migrants from SSA to Italy.

METHODS

A decision tree and a Markov model were developed to assess the health and economic impacts of three interventions: (i) passive diagnosis for symptomatic patients (current practice in Italy); (ii) serological screening of all migrants and treating those found positive and (iii) presumptive treatment for all migrants with praziquantel in a single dose. The time horizon of analysis was one year to determine the exact expenses, and 28 years to consider possible sequelae, in the Italian health-care perspective. Data input was derived from available literature; costs were taken from the price list of Careggi University Hospital, Florence, and from National Hospitals Records.

RESULTS

Assuming a population of 100 000 migrants with schistosomiasis prevalence of 21·2%, the presumptive treatment has a greater clinical impact with 86.3% of the affected being cured (75.2% in screening programme and 44.9% in a passive diagnosis strategy). In the first year, the presumptive treatment and the screening strategy compared with passive diagnosis prove cost-effective (299 and 595 cost/QALY, respectively). In the 28-year horizon, the two strategies (screening and presumptive treatment) compared with passive diagnosis become dominant (less expensive with more QALYs) and cost-saving.

CONCLUSION

The results of the model suggest that presumptive treatment and screening strategies are more favourable than the current passive diagnosis in the public health management of schistosomiasis in SSA migrants, especially in a longer period analysis.

Toripalimab plus chemotherapy vs. chemotherapy in patients with advanced non-small-cell lung cancer: A cost-effectiveness analysis

Background: The potency and safety of toripalimab combination with chemotherapy (TC) as the first-line therapy for advanced non-small cell lung cancer (NSCLC) have been demonstrated in the CHOICE-01 study. Our research explored whether TC was cost-effective compared to chemotherapy alone from the Chinese payer perspective. Materials and methods: Clinical parameters were obtained from a randomized, multicenter, registrational, placebo-controlled, double-blind, phase III trial. Standard fee databases and previously published literature were used to determine costs and utilities. A Markov model with three mutually exclusive health statuses (progression-free survival (PFS), disease progression, and death) was used to predict the disease course. The costs and utilities were discounted at 5% per annum. The main endpoints of the model included cost, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER). Univariate and probabilistic sensitivity analyses were performed to investigate the uncertainty. Subgroup analyses were performed to verify the cost-effectiveness of TC in patients with squamous and non-squamous cancer. Results: TC combination therapy yielded an incremental 0.54 QALYs with an incremental cost of $11,777, compared to chemotherapy, giving rise to ICERs of $21,811.76/QALY. Probabilistic sensitivity analysis revealed that TC was not favorable at 1 time GDP per capita. With a prespecified willingness-to-pay threshold (WTP) of three times the GDP per capita, combined treatment had a 100% probability of being cost-effective and had substantial cost-effectiveness in advanced NSCLC. Probabilistic sensitivity analyses showed that TC was more likely to be accepted with a WTP threshold higher than $22,195 in NSCLC. Univariate sensitivity analysis showed that the utility of PFS state, crossover proportions of the chemotherapy arm, cost per cycle of pemetrexed treatment, and discount rate were the dominant influencing factors. Subgroup analyses found that in patients with squamous NSCLC, the ICER was $14,966.09/QALY. In the non-squamous NSCLC, ICER raised to $23,836.27/QALY. ICERs were sensitive to the variance of the PFS state utility. TC was more likely to be accepted when WTP increases exceeded $14,908 in the squamous NSCLC subgroup and $23,409 in the non-squamous NSCLC subgroup. Conclusion: From the perspective of the Chinese healthcare system, TC may be cost-effective in individuals with previously untreated advanced NSCLC at the prespecified WTP threshold compared to chemotherapy, and more significant in individuals with squamous NSCLC, which will provide evidence for clinicians to make the best decisions in general clinical practice.

Cost-Effectiveness Analysis of Universal Screening for Biliary Atresia in Japan

OBJECTIVE

To evaluate the cost-effectiveness of universal newborn screening using stool color card or direct bilirubin (DB) testing when comparing with no screening for biliary atresia in Japanese setting.

STUDY DESIGN

A decision analytic Markov microsimulation model was developed to evaluate the universal screening for biliary atresia. Our screening strategies included stool color card, DB, or no screening. The outcomes of all newborns undergoing 3 strategies were simulated to analyze event-free life-years defined as liver transplant-free survival, costs, and incremental cost-effectiveness ratio (ICER) over a 25-year period with an annual discount rate of 2% applied for both costs and outcomes. A 1-way sensitivity analysis was performed to assess the uncertainty.

RESULTS

There were 941 000 newborn infants in our cohort and 114 cases of biliary atresia. The base case analysis showed that the stool color card strategy was $14 927 337 higher than no screening with an increase in 44 more event-free life-years gained, resulting in an ICER of $339 258 per event-free life-year gained. The DB screening strategy compared with stool color card was $138 994 060 higher with an increase in 271 more event-free life-years gained and an ICER of $512 893 per event-free life-year gained. The DB screening strategy compared with no screening resulted in an ICER of $488 639 per event-free life-year gained. The DB screening resulted in 16 fewer liver transplants than stool color card and stool color card had 2 fewer liver transplants than no screening.

CONCLUSIONS

Universal screening for biliary atresia could be cost-effective depending on the willingness to pay thresholds for health benefits.

Performance Analysis of IEEE 802.11p MAC with Considering Capture Effect under Nakagami-m Fading Channel in VANETs

Vehicular ad hoc networks (VANETs) have recently drawn a large amount of attention because of their enormous potential in road safety improvement and traffic management as well as infotainment service support. As the standard of medium access control (MAC) and physical (PHY) layers for VANETs, IEEE 802.11p has been proposed for more than a decade. Though performance analyses of IEEE 802.11p MAC have been performed, the existing analytical methods still need to be improved. In this paper, to assess the saturated throughput and the average packet delay of IEEE 802.11p MAC in VANETs, a two-dimensional (2-D) Markov model is introduced by considering the capture effect under Nakagami-m fading channel. Moreover, the closed-form expressions of successful transmission, collided transmission, saturated throughput, and average packet delay are carefully derived. Finally, the simulation results are demonstrated to verify the accuracy of the proposed analytical model, which also proves that this analytical model is more precise than the existing ones in terms of saturated throughput and average packet delay.

Markov Cohort State-Transition Model: A Multinomial Distribution Representation

HIGHLIGHTS

A Markov model simulates the average experience of a cohort of patients.Monte Carlo simulation, the standard approach for estimating the variance, is computationally expensive.A multinomial distribution provides an exact representation of a Markov model.Using the known formulas of a multinomial distribution, the mean and variance of a Markov model can be readily calculated.

Network meta-analysis and cost-effectiveness analysis of infliximab, cyclosporine and tacrolimus for ulcerative colitis

BACKGROUND

Assess the efficiency and cost-effectiveness of infliximab, cyclosporine and tacrolimus for the treatment of ulcerative colitis (UC).

METHODS

A literature search identified studies that investigated infliximab, cyclosporine or tacrolimus compared with placebo in UC patients. Short-term, long-term remission rates and response rates were employed to assess efficacy. Odds ratios with 95% confidence intervals were analyzed. A Markov model was constructed to simulate the progression in a cohort of patients with UC, with an over 10 years of time horizon, with a discount rate of 3%, and established threshold of €30,000/quality-adjusted life-year (QALY) or ¥82442/QALY.

RESULTS

Results of network meta-analysis showed that the order was cyclosporine, tacrolimus, infliximab and placebo from high rate to low with regard to short-term clinical response. The comparison between infliximab versus cyclosporine achieved an incremental cost effectiveness ratio (ICER) of €184435/QALY and ¥531607/QALY, with a 0.34893 QALYs difference of efficacy, and an incremental cost of €64355 and ¥185494. Tacrolimus versus cyclosporine reached an ICER of €44236/QALY and ¥57494/QALY, with a difference of 0.40963 QALYs in efficacy, and a raising cost to €18120 and ¥23551. The probabilistic sensitivity analysis shows that cyclosporine would be cost-effective in the 75.8% of the simulations, tacrolimus in the 24.2%, and infliximab for the 0%.

CONCLUSION

Infliximab, cyclosporine and tacrolimus as salvage therapies are efficacious. For long-term of clinical remission, the order of pharmacological agents was tacrolimus, infliximab and cyclosporine from high efficacy to low while no significant difference is seen. In cost-effectiveness analysis, the cyclosporine versus infliximab or tacrolimus is expected to be at best.

The Kenevo microprocessor-controlled prosthetic knee compared with non-microprocessor-controlled knees in individuals older than 65 years in Sweden: A cost-effectiveness and budget-impact analysis

BACKGROUND

Growing evidence suggests that individuals with transfemoral amputation or knee disarticulation using a prosthesis equipped with a microprocessor-controlled knee (MPK) benefit from enhanced mobility and safety, including less falls. In elderly individuals, high mortality rates are assumed to reduce the expected useful life of MPKs, and this raises concerns regarding their economic effectiveness.

OBJECTIVE

To investigate the cost-effectiveness and budget impact of the Kenevo/MPK (Ottobock, Germany) compared with non-microprocessor-controlled knees (NMPKs) in people older than 65 years at the time of transfemoral amputation/knee disarticulation, from a Swedish payer's perspective.

METHODS

A decision-analytic model was developed to conduct the economic analysis of the Kenevo/MPK. Model parameters were derived from Swedish databases and published literature. Univariate and probabilistic sensitivity analyses were performed to explore parameter uncertainty.

RESULTS

Compared with NMPKs, the Kenevo/MPK reduced the frequency of hospitalizations by 137 per 1,000 person years while the frequency of fatal falls was reduced by 19 per 1,000 person-years in the simulation. Over a 25-year time horizon, the incremental cost-effectiveness ratio was EUR11,369 per quality-adjusted life year. The probability of the MPK being cost-effective at a threshold of EUR40,000 per quality-adjusted life year was 99%. The 5-year budget impact model predicted an increase in payer expenditure of EUR1.76 million if all new patients received a Kenevo/MPK, and 50% of current NMPK users switched to the MPK.

CONCLUSIONS

Results of the modeling suggest that the Kenevo/MPK is likely to be cost-effective for elderly individuals, primarily because of a reduction in falls.

Cost-Effectiveness of Pembrolizumab Plus Chemotherapy as First-Line Therapy for Advanced Oesophageal Cancer

Objective: Pembrolizumab plus chemotherapy is recommended as the first-line treatment for advanced oesophageal cancer. The objective of this study is to evaluate the cost-effectiveness of pembrolizumab plus chemotherapy as first-line therapy for advanced oesophageal cancer from the healthcare system perspective in China.

Methods: Based on the KEYNOTE-590 trial, a Markov model was constructed to estimate the cost and effectiveness of pembrolizumab plus chemotherapy and placebo plus chemotherapy, respectively. Total costs, life years (LYs), quality-adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICERs) were calculated. One-way, probabilistic sensitivity analyses (PSA), and subgroup analyses were adapted to test the model robustness.

Result: Compared with the placebo group, pembrolizumab group obtained an additional 1.05 QALY, but the cost was also increased by $121,478.76. The ICER was $115,391.84 per QALY gained, which was higher than the willingness-to-pay (WTP) of $31,304.31. The results of One-way sensitivity analyses showed that the ICER was sensitive to the hazard ratio of PFS and per cycle cost of pembrolizumab. At a WTP threshold of $31,304.31, the probability of pembrolizumab plus chemotherapy being cost-effective was 0%.

Conclusion: From the perspective of China healthcare system, pembrolizumab plus chemotherapy as first-line treatment is not cost-effective for patients with advanced oesophageal cancer compared with placebo plus chemotherapy.

Sintilimab Plus Bevacizumab Biosimilar Versus Sorafenib as First-Line Treatment for Unresectable Hepatocellular Carcinoma: A Cost-Effectiveness Analysis

Objective: The ORIENT-32 clinical trial revealed that sintilimab plus bevacizumab biosimilar significantly improved the median progression-free survival and median overall survival (OS) compared with sorafenib. This analysis evaluated the cost-effectiveness of sintilimab plus bevacizumab biosimilar as a first-line treatment for unresectable hepatocellular carcinoma from the Chinese perspective of healthcare system.

Materials and methods: A Markov model with three mutual health states was constructed to evaluate the economic outcome of sintilimab plus bevacizumab biosimilar. The model cycle was 21 days, and the simulation time horizon was a lifetime. The output parameters of the model were the total cost, life-year (LY), quality-adjusted LY (QALY), and incremental cost-effectiveness ratio (ICER). Sensitivity analyses were conducted to assess the robustness of the results.

Results: The base-case results found that sintilimab plus bevacizumab biosimilar provided an improvement of 1.27 QALYs and 1.84 LYs compared with sorafenib, and the ICER was $23,352/QALY. The hazard ratio for OS had the greatest influence on the ICER. The probability of sintilimab plus bevacizumab biosimilar was 85% at willingness-to-pay thresholds of $30,552/QALY.

Conclusion: The findings of this analysis suggested that sintilimab plus bevacizumab biosimilar was a cost-effective first-line therapy for patients with unresectable hepatocellular carcinoma.

Estimating Treatment-Switching Bias in a Randomized Clinical Trial of Ovarian Cancer Treatment: Combining Causal Inference with Decision-Analytic Modeling

BACKGROUND

Bevacizumab is efficacious in delaying ovarian cancer progression and controlling ascites. The ICON7 trial showed a significant benefit in overall survival for bevacizumab, whereas the GOG-218 trial did not. GOG-218 allowed control group patients to switch to bevacizumab upon progression, which may have biased the results. Lack of data on switching behavior prevented the application of g-methods to adjust for switching. The objective of this study was to apply decision-analytic modeling to estimate the impact of switching bias on causal treatment-effect estimates.

METHODS

We developed a causal decision-analytic Markov model (CDAMM) to emulate the GOG-218 trial and estimate overall survival. CDAMM input parameters were based on data from randomized clinical trials and the published literature. Overall switching proportion was based on GOG-218 trial information, whereas the proportion switching with and without ascites was estimated using calibration. We estimated the counterfactual treatment effect that would have been observed had no switching occurred by denying switching in the CDAMM.

RESULTS

The survival curves generated by the CDAMM matched well with the ones reported in the GOG-218 trial. The survival curve correcting for switching showed an estimated bias such that 79% of the true treatment effect could not be observed in the GOG-218 trial. Results were most sensitive to changes in the proportion progressing with severe ascites and mortality.

LIMITATIONS

We used a simplified model structure and based model parameters on published data and assumptions. Robustness of the CDAMM was tested and model assumptions transparently reported.

CONCLUSIONS

Medical-decision science methods may be merged with empirical methods of causal inference to integrate data from other sources where empirical data are not sufficient. We recommend collecting sufficient information on switching behavior when switching cannot be avoided.

Budget Impact Analysis of Treatment Flow Optimization in Epilepsy Patients: Estimating Potential Impacts with Increased Referral Rate to Specialized Care

Objectives: We developed a Markov model to simulate a treatment flow of epilepsy patients who refer to specialized care from non-specialized care, and to surgery from specialized care for estimation of patient distributions and expenditures caused by increasing the referral rate for specialized care. Methods: This budget impact analysis of treatment flow optimization in epilepsy patients was performed as a long-term simulation using the Markov model by comparing the current treatment flow and the optimized treatment flow. In the model, we simulated the prognosis of new onset 5-year-old epilepsy patients (assuming to represent epilepsy occurring between 0 and 10 years of age) treated over a lifetime period. Direct costs of pharmacotherapies, management fees and surgeries are included in the analysis to evaluate the annual budget impact in Japan. Results: In the current treatment flow, the number of refractory patients treated with four drugs by non-specialized care were estimated as 8766 and yielded JPY5.8 billion annually. However, in the optimized treatment flow, the number of patients treated with four drugs by non-specialized care significantly decreased and who continued the monotherapy increased. The costs for the four-drug therapy by non-specialized care were eliminated. Hence cost-saving of JPY9.5 billion (-5% of the current treatment flow) in total national expenditures would be expected. Conclusion: This study highlights that any policy decision-making for referral optimization to specialized care in appropriate epilepsy patients would be feasible with a cost-savings or very few budget impacts. However, important information in the decision-making such as transition probability to the next therapy or excuse for sensitive limitations is not available currently. Therefore, further research with reliable data such as big data analysis or a national survey with real-world treatment patterns is needed.

Utilization of Time Series Tools in Life-sciences and Neuroscience

Time series tools are part and parcel of modern day research. Their usage in the biomedical field; specifically, in neuroscience, has not been previously quantified. A quantification of trends can tell about lacunae in the current uses and point towards future uses. We evaluated the principles and applications of few classical time series tools, such as Principal Component Analysis, Neural Networks, common Auto-regression Models, Markov Models, Hidden Markov Models, Fourier Analysis, Spectral Analysis, in addition to diverse work, generically lumped under time series category. We quantified the usage from two perspectives, one, information technology professionals', other, researchers utilizing these tools for biomedical and neuroscience research. For understanding trends from the information technology perspective, we evaluated two of the largest open source question and answer databases of Stack Overflow and Cross Validated. We quantified the trends in their application in the biomedical domain, and specifically neuroscience, by searching literature and application usage on PubMed. While the use of all the time series tools continues to gain popularity in general biomedical and life science research, and also neuroscience, and so have been the total number of questions asked on Stack overflow and Cross Validated, the total views to questions on these are on a decrease in recent years, indicating well established texts, algorithms, and libraries, resulting in engineers not looking for what used to be common questions a few years back. The use of these tools in neuroscience clearly leaves room for improvement.

Cost-Effectiveness of the Use of Gold Anchor™ Markers in Prostate Cancer

Introduction

A common treatment for prostate cancer is external beam radiation therapy. A way to target the radiation is to use implantable gold fiducial markers (GFMs). The GFMs serve as reference points enabling tumor localization during treatment. Today, there are several GFMs available on the market but no clinical guidelines as to which one to use. The aim of this study was to estimate the cost-effectiveness of Gold Anchor GFMs (Naslund Medical AB, Huddinge, Sweden) implanted with a 22G needle, compared to other GFMs implanted with a 17-18G needle, in the prostate gland of patients with prostate cancer.

Methods

Costs, life years, and quality-adjusted life years (QALYs) were estimated over a lifelong time horizon for each treatment strategy using a decision-analytic model. Data used in the model were obtained from published literature or were estimated by an expert elicitation technique. The primary outcome measure was an incremental cost-effectiveness ratio (ICER).

Results

Gold Anchor GFM was found to be a dominant alternative with both lower costs [-8.7 US Dollars (USD)] and a gain in QALYs (0.015) when compared with other GFMs. The lower cost was achieved by fewer visits for imaging in treatment planning, and by reduced risk of infections and sepsis. The QALY gain was driven by a reduced risk of sepsis.

Conclusion

The use of Gold Anchor GFMs as reference points to target radiation is a cost-effective alternative when compared to other GFMs. However, this analysis is based on expert elicitation regarding some crucial parameters, and further clinical studies of the use of GFMs are needed.

Cost-utility model of brivaracetam in the adjunctive treatment of patients with epilepsy in Spain

OBJECTIVE

This study aims to assess the cost utility of Brivaracetam compared with the third-generation anti-epileptic drugs used as standard care.

METHODS

A cost utility analysis of Brivaracetam was carried out with other third-generation comparators. The treatment pathway of a hypothetical cohort over a period of 2 years was simulated using the Markov model. Data for effectiveness and the QALYs of each health status for epilepsy, as well as for the disutilities of adverse events of treatments, were analyzed through a studies review. The cost of the anti-epileptics and the use of medical resources linked to the different health statuses were taken into consideration. A probabilistic sensitivity analysis was performed using a Monte Carlo simulation.

RESULTS

Brivaracetam was shown to be the dominant alternative, with Incremental Cost Utility Ratio (ICUR) values from -11,318 for Lacosamide to -128,482 for Zonisamide. The probabilistic sensitivity analysis validates these results. The ICUR sensitivity is greater for increases in the price of Brivaracetam than for decreases, and for Eslicarbizapine over the other adjunctives considered in the analysis.

CONCLUSIONS

Treatment with Brivaracetam resulted in cost effective and incremental quality adjusted life years come at an acceptable cost.

Update of Markov Model on the Cost-effectiveness of Nonpharmacologic Interventions for Chronic Low Back Pain Compared to Usual Care

STUDY DESIGN

Markov model.

OBJECTIVE

Further validity test of a previously published model.

SUMMARY OF BACKGROUND DATA

The previous model was built using data from ten randomized trials and examined the 1-year effectiveness and cost-effectiveness of 17 nonpharmacologic interventions for chronic low back pain (CLBP), each compared to usual care alone. This update incorporated data from five additional trials.

METHODS

Based on transition probabilities that were estimated using patient-level trial data, a hypothetical cohort of CLBP patients transitioned over time among four defined health states: high-impact chronic pain with substantial activity limitations; higher (moderate-impact) and lower (low-impact) pain without activity limitations; and no pain. As patients transitioned among health states, they accumulated quality-adjusted life-years, as well as healthcare and productivity costs. Costs and effects were calculated incremental to each study's version of usual care.

RESULTS

From the societal perspective and assuming a typical patient mix (25% low-impact, 35% moderate-impact, and 40% high-impact chronic pain), most interventions-including those newly added-were cost-effective (<$50,000/QALY) and demonstrated cost savings. From the payer perspective, fewer were cost-saving, but the same number were cost-effective. Results for the new studies generally mirrored others using the same interventions-for example, cognitive behavioral therapy (CBT) and physical therapy. A new acupuncture study had similar effectiveness to other acupuncture studies, but higher usual care costs, resulting in higher cost savings. Two new yoga studies' results were similar, but both differed from those of the original yoga study. Mindfulness-based stress reduction was similar to CBT for a typical patient mix but was twice as effective for those with high-impact chronic pain.

CONCLUSION

Markov modeling facilitates comparisons across interventions not directly compared in trials, using consistent outcome measures after balancing the baseline mix of patients. Outcomes also differed by pain impact level, emphasizing the need to measure CLBP subgroups.

LEVEL OF EVIDENCE

N/A.

Cortical encoding of melodic expectations in human temporal cortex

Humans engagement in music rests on underlying elements such as the listeners' cultural background and interest in music. These factors modulate how listeners anticipate musical events, a process inducing instantaneous neural responses as the music confronts these expectations. Measuring such neural correlates would represent a direct window into high-level brain processing. Here we recorded cortical signals as participants listened to Bach melodies. We assessed the relative contributions of acoustic versus melodic components of the music to the neural signal. Melodic features included information on pitch progressions and their tempo, which were extracted from a predictive model of musical structure based on Markov chains. We related the music to brain activity with temporal response functions demonstrating, for the first time, distinct cortical encoding of pitch and note-onset expectations during naturalistic music listening. This encoding was most pronounced at response latencies up to 350 ms, and in both planum temporale and Heschl's gyrus.

A Trial-Based Cost-Utility Analysis of Metastasis-Directed Therapy for Oligorecurrent Prostate Cancer

The optimal management of patients with oligorecurrent prostate cancer (PCa) is unknown. There is growing interest in metastasis-directed therapy (MDT) for this population. The objective was to assess cost-utility from a Belgian healthcare payer’s perspective of MDT and delayed androgen deprivation therapy (ADT) in comparison with surveillance and delayed ADT, and with immediate ADT. A Markov decision-analytic trial-based model was developed, projecting the results over a 5-year time horizon with one-month cycles. Clinical data were derived from the STOMP trial and literature. Treatment costs were derived from official government documents. Probabilistic sensitivity analyses showed that MDT is cost-effective compared to surveillance (ICER: €8393/quality adjusted life year (QALY)) and immediate ADT (dominant strategy). The ICER is most sensitive to utilities in the different health states and the first month MDT cost. At a willingness-to-pay threshold of €40,000 per QALY, the cost of the first month MDT should not exceed €8136 to be cost-effective compared to surveillance. The Markov-model suggests that MDT for oligorecurrent PCa is potentially cost-effective in comparison with surveillance and delayed ADT, and in comparison with immediate ADT.

Cost-Effectiveness Analysis and Decision Modelling: A Tutorial for Clinicians

Cost-effectiveness analysis (CEA) provides information on how much extra do we need to spend per unit gain in health outcomes with introduction of any new healthcare intervention or treatment as compared to the alternative. This information is crucial to make decision regarding funding any new drug, diagnostic test or determining standard treatment protocol. It becomes even more important to consider this evidence in resource constrained low-income and middle-income country settings. Generating evidence on costs and consequences of a treatment or intervention could be performed in the setting of a randomized controlled trial, which is the perfect platform to evaluate efficacy or effectiveness. However, we argue that randomized controlled trial (RCT) offers an incomplete setting to generate comprehensive data on all costs and consequences for the purpose of a CEA. Hence, it is needed to use a decision model, either in combination with the evidence from RCT or alone. In this article, we demonstrate the application of decision model-based economic evaluation using 2 separate techniques - a decision tree and a Markov model. We argue that application of a decision model allows computation of health benefits in terms of utility-based measure such as a quality-adjusted life year or disability-adjusted life year which is preferred for a CEA, measure distal costs and consequences which are much more downstream to the application of intervention, allows comparison with multiple intervention and comparators, and provides opportunity of making use of evidence from multiple sources rather than a single RCT which may have limited generalizability. This makes the use of such evidence much more acceptable for clinical use and policy relevant.

Are Nonpharmacologic Interventions for Chronic Low Back Pain More Cost Effective Than Usual Care? Proof of Concept Results From a Markov Model

STUDY DESIGN

Markov model.

OBJECTIVE

Examine the 1-year effectiveness and cost-effectiveness (societal and payer perspectives) of adding nonpharmacologic interventions for chronic low back pain (CLBP) to usual care using a decision analytic model-based approach.

SUMMARY OF BACKGROUND DATA

Treatment guidelines now recommend many safe and effective nonpharmacologic interventions for CLBP. However, little is known regarding their effectiveness in subpopulations (e.g., high-impact chronic pain patients), nor about their cost-effectiveness.

METHODS

The model included four health states: high-impact chronic pain (substantial activity limitations); no pain; and two others without activity limitations, but with higher (moderate-impact) or lower (low-impact) pain. We estimated intervention-specific transition probabilities for these health states using individual patient-level data from 10 large randomized trials covering 17 nonpharmacologic therapies. The model was run for nine 6-week cycles to approximate a 1-year time horizon. Quality-adjusted life-year weights were based on six-dimensional health state short form scores; healthcare costs were based on 2003 to 2015 Medical Expenditure Panel Survey data; and lost productivity costs used in the societal perspective were based on reported absenteeism. Results were generated for two target populations: (1) a typical baseline mix of patients with CLBP (25% low-impact, 35% moderate-impact, and 40% high-impact chronic pain) and (2) high-impact chronic pain patients.

RESULTS

From the societal perspective, all but two of the therapies were cost effective (<$50,000/quality-adjusted life-year) for a typical patient mix and most were cost saving. From the payer perspective fewer were cost saving, but the same number was cost-effective. Assuming all patients in the model have high-impact chronic pain increases the effectiveness and cost-effectiveness of most, but not all, therapies indicating that substantial benefits are possible in this subpopulation.

CONCLUSION

Modeling leverages the evidence produced from clinical trials to provide more information than is available in the published studies. We recommend modeling for all existing studies of nonpharmacologic interventions for CLBP.

LEVEL OF EVIDENCE

4.

Cost-effectiveness analysis of positron-emission tomography-computed tomography in preoperative staging for nonsmall-cell lung cancer with resected monometastatic disease

BACKGROUND

The aim of this study was, from the Chinese healthcare perspective, to assess the cost-effectiveness of positron-emission tomography-computed tomography (PET-CT) with F-fluorodeoxyglucose (F-FDG) in preoperation staging for nonsmall-cell lung cancer (NSCLC) with resected monometastatic disease based on a retrospective study. This study was conducted from January 2017 to February 2019 at an academic hospital.

METHODS

A Markov model and 3 decision-tree models were designed to calculate the long-term medical costs, outcomes, and incremental cost-effectiveness ratios (ICERs) of the 2 diagnostic strategies (PET-CT and conventional CT). Model robustness was assessed in sensitivity analyses.

RESULTS

For the base-case analysis, preoperative PET-CT evaluation for NSCLC with resected monometastatic disease provided an additional 1.475, 2.129, and 2.412 life-years (LYs), in the time horizon of 10-, 20-, and 30-year, respectively, and the ICERs for the PET-CT group compared with the conventional CT group were $1153, $1393, and $1430 per LY, separately. The acceptability curves demonstrated that when the willingness-to-pay (WTP) thresholds ranged from $500 to $3000/LY, the probability of cost-effectiveness changed varied dramatically, and at WTP > $3000, the probability that the PET-CT group achieved cost-effectiveness was 100%. Sensitivity analyses suggested that the models we designed were robust.

CONCLUSION

Compared with conventional CT scan, preoperative F-FDG PET-CT evaluation for patients with resected monometastatic NSCLC is cost-effective from the Chinese healthcare perspective. Preoperative F-FDG PET-CT evaluation should be popularized for patients with resected monometastatic NSCLC.

Assessing the Lifetime Cost-Effectiveness of Low-Protein Infant Formula as Early Obesity Prevention Strategy: The CHOP Randomized Trial

Background: Although there is a growing number of early childhood obesity prevention programs, only a few of them are effective in the long run. Even fewer reports exist on lifetime cost-effectiveness of early prevention strategies. This paper aimed to assess the lifetime cost-effectiveness of infant feeding modification aiming at reducing risk of later obesity. Methods: The simulation model consists of two parts: (a) Model I used data from the European Childhood Obesity Project (CHOP) trial (up to 6 years) and the German Interview and Examination Survey for Children (KiGGS) (6–17 years) to evaluate BMI trajectories of infants receiving either lower protein (LP) or higher protein (HP) content formula; and (b) Model II estimated lifetime cost-effectiveness based on Model I BMI trajectories. Compared to HP formula, LP formula feeding would incur lower costs that are attributable to childhood obesity across all decades of life. Results: Our analysis showed that LP formula would be cost-effective in terms of a positive net monetary benefit (discounted 3%) as an obesity prevention strategy. For the 19% of infants fed with formula in Germany, the LP strategy would result in cost savings of € 2.5 billion. Conclusions: Our study is one of the first efforts to provide much-needed cost-effectiveness evidence of infant feeding modification, thereby potentially motivating interventionists to reassess their resource allocation.

Model-based evaluation of the long-term cost-effectiveness of systematic case-finding for COPD in primary care

Introduction

‘One-off’ systematic case-finding for COPD using a respiratory screening questionnaire is more effective and cost-effective than routine care at identifying new cases. However, it is not known whether early diagnosis and treatment is beneficial in the longer term. We estimated the long-term cost-effectiveness of a regular case-finding programme in primary care.

Methods

A Markov decision analytic model was developed to compare the cost-effectiveness of a 3-yearly systematic case-finding programme targeted to ever smokers aged ≥50 years with the current routine diagnostic process in UK primary care. Patient-level data on case-finding pathways was obtained from a large randomised controlled trial. Information on the natural history of COPD and treatment effects was obtained from a linked COPD cohort, UK primary care database and published literature. The discounted lifetime cost per quality-adjusted life-year (QALY) gained was calculated from a health service perspective.

Results

The incremental cost-effectiveness ratio of systematic case-finding versus current care was £16 596 per additional QALY gained, with a 78% probability of cost-effectiveness at a £20 000 per QALY willingness-to-pay threshold. The base case result was robust to multiple one-way sensitivity analyses. The main drivers were response rate to the initial screening questionnaire and attendance rate for the confirmatory spirometry test.

Discussion

Regular systematic case-finding for COPD using a screening questionnaire in primary care is likely to be cost-effective in the long-term despite uncertainties in treatment effectiveness. Further knowledge of the natural history of case-found patients and the effectiveness of their management will improve confidence to implement such an approach.

Cost effectiveness of Gene Expression Profiling in Patients with Early-Stage Breast Cancer in a Middle-Income Country, Turkey: Results of a Prospective Multicenter Study

Objective

Breast cancer is a heterogenous disease, and genetic profiling helps to individualize adjuvant treatment. The Oncotype DX is a validated test to predict benefit of adjuvant systemic treatment. The aims of this study are to determine the costs of chemotherapy in government hospitals in Turkey and evaluate the cost-effectiveness of the Oncotype DX from the national insurance perspective.

Materials and Methods

A Markov model was developed to make long term projections of distant recurrence, survival, quality adjusted life expectancy, and direct costs for patients with ER+, HER2-, node-negative or up to 3 node-positive early stage breast cancer. Turkish decision impact study patient data were captured for model reference. In that study, ten academic centers across Turkey participated in a prospective trial. Of 165 patients with pT1-3, pN0-N1mic, ER-positive, and HER-2 negative tumors, 57% had low recurrence score (RS), 35% had intermediate RS, and 8% had high RS, respectively. The overall rate of change in chemotherapy treatment decisions following Oncotype DX was 33%.

Results

The cost of adjuvant chemotherapy in public hospitals was estimated at $3.649, and Oncotype Dx test was $5.141. Based on the cost-effectiveness analysis, Oncotype DX testing was estimated to improve life expectancy (+0.86 years) and quality-adjusted life expectancy (+0.68 QALYs) versus standard care. The incremental cost-effectiveness ratio (ICERs) of Oncotype DX was estimated to be $7207.9 per QALY gained and $5720.6 per LY gained versus current clinical practice.

Conclusion

As Oncotype DX was found both cost-effective and life-saving from a national perspective, the test should be introduced to standard care in patients with ER+, HER-2 negative early-stage breast cancer in Turkey.

Markov Models for Detection of Ventricular Arrhythmia

The advent of portable cardiac monitoring devices has enabled real-time analysis of cardiac signals. These devices can be used to develop algorithms for real-time detection of dangerous heart rhythms such as ventricular arrhythmias. This paper presents a Markov model based algorithm for real-time detection of ventricular tachycardia, ventricular flutter, and ventricular fibrillation episodes. The algorithm does not rely on any noise removal pre-processing or peak annotation of the original signal. When evaluated using ECG signals from three publicly available databases, the model resulted in an AUC of 0.96 and F1-score of 0.91 for 5-second long signals and an AUC of 0.97 and F1-score of 0.93 for 2-second long signals.

Alternative Conversion Methods for Transition Probabilities in State-Transition Models: Validity and Impact on Comparative Effectiveness and Cost-Effectiveness

Background. In state-transition models (STMs), decision problems are conceptualized using health states and transitions among those health states after predefined time cycles. The naive, commonly applied method (C) for cycle length conversion transforms all transition probabilities separately. In STMs with more than 2 health states, this method is not accurate. Therefore, we aim to describe and compare the performance of method C with that of alternative matrix transformation methods. Design. We compare 2 alternative matrix transformation methods (Eigenvalue method [E], Schure-Padé method [SP]) to method C applied in an STM of 3 different treatment strategies for women with breast cancer. We convert the given annual transition matrix into a monthly-cycle matrix and evaluate induced transformation errors for the transition matrices and the long-term outcomes: life years, quality-adjusted life-years, costs and incremental cost-effectiveness ratios, and the performance related to the decisions. In addition, we applied these transformation methods to randomly generated annual transition matrices with 4, 7, 10, and 20 health states. Results. In theory, there is no generally applicable correct transformation method. Based on our simulations, SP resulted in the smallest transformation-induced discrepancies for generated annual transition matrices for 2 treatment strategies. E showed slightly smaller discrepancies than SP in the strategy, where one of the direct transitions between health states was excluded. For long-term outcomes, the largest discrepancy occurred for estimated costs applying method C. For higher dimensional models, E performs best. Conclusions. In our modeling examples, matrix transformations (E, SP) perform better than transforming all transition probabilities separately (C). Transition probabilities based on alternative conversion methods should therefore be applied in sensitivity analyses.

Identification via Numerical Computation of Transcriptional Determinants of a Cell Phenotype Decision Making

Complex cellular processes, such as phenotype decision making, are exceedingly difficult to analyze experimentally, due to the multiple-layer regulation of gene expression and the intercellular variability referred to as biological noise. Moreover, the heterogeneous experimental approaches used to investigate distinct macromolecular species, and their intrinsic differential time-scale dynamics, add further intricacy to the general picture of the physiological phenomenon. In this respect, a computational representation of the cellular functions of interest can be used to extract relevant information, being able to highlight meaningful active markers within the plethora of actors forming an active molecular network. The multiscale power of such an approach can also provide meaningful descriptions for both population and single-cell level events. To validate this paradigm a Boolean and a Markov model were combined to identify, in an objective and user-independent manner, a signature of genes recapitulating epithelial to mesenchymal transition in-vitro. The predictions of the model are in agreement with experimental data and revealed how the expression of specific molecular markers is related to distinct cell behaviors. The presented method strengthens the evidence of a role for computational representation of active molecular networks to gain insight into cellular physiology and as a general approach for integrating in-silico/in-vitro study of complex cell population dynamics to identify their most relevant drivers.

Impact of surveillance for hepatocellular carcinoma on survival in patients with compensated cirrhosis

Surveillance for hepatocellular carcinoma (HCC) has been recommended in patients with cirrhosis. In this study, we examined the extent to which the competing risk of hepatic decompensation influences the benefit of HCC surveillance by investigating the impact of availability of liver transplantation (LTx) and the rate of progression of hepatic decompensation on survival gain from HCC surveillance. A multistate Markov model was constructed simulating a cohort of 50-year-old patients with compensated cirrhosis. The primary outcome of interest was all-cause and HCC-specific mortality. The main input data included incidence of HCC, sensitivity of screening test, and mortality from hepatic decompensation. Treatment modalities modeled included LTx, resection, and radiofrequency ablation. In the base case scenario, LTx would be available to prevent death in a certain proportion of patients. In the absence of surveillance, 68.2% of the cohort members died within 15 years; of these decedents, 25.1% died from HCC and 43.6% died from hepatic decompensation. With surveillance, the median survival improved from 10.4 years to 11.2 years. The number of subjects under surveillance needed to reduce one all-cause and one HCC-specific death over 15 years was 28 and 18, respectively. In sensitivity analyses, incidence of HCC and progression of cirrhosis had the strongest effect on the benefit of surveillance, whereas LTx availability had a negligible effect.

CONCLUSION

HCC surveillance decreases all-cause and tumor-specific mortality in patients with compensated cirrhosis regardless of LTx availability. In addition, incidence of HCC and sensitivity of surveillance test also had a substantial impact on the benefits of surveillance. (Hepatology 2018;68:78-88).

Transplanting hepatitis C virus-positive livers into hepatitis C virus-negative patients with preemptive antiviral treatment: A modeling study

Under current guidelines, hepatitis C virus (HCV)-positive livers are not transplanted into HCV-negative recipients because of adverse posttransplant outcomes associated with allograft HCV infection. However, HCV can now be cured post-LT (liver transplant) using direct-acting antivirals (DAAs) with >90% success; therefore, HCV-negative patients on the LT waiting list may benefit from accepting HCV-positive organs with preemptive treatment. Our objective was to evaluate whether and in which HCV-negative patients the potential benefit of accepting an HCV-positive (i.e., viremic) organ outweighed the risks associated with HCV allograft infection. We developed a Markov-based mathematical model that simulated a virtual trial of HCV-negative patients on the LT waiting list to compare long-term outcomes in patients: (1) willing to accept any (HCV-negative or HCV-positive) liver versus (2) those willing to accept only HCV-negative livers. Patients receiving HCV-positive livers were treated preemptively with 12 weeks of DAA therapy and had a higher risk of graft failure than those receiving HCV-negative livers. The model incorporated data from published studies and the United Network for Organ Sharing (UNOS). We found that accepting any liver regardless of HCV status versus accepting only HCV-negative livers resulted in an increase in life expectancy when Model for End-Stage Liver Disease (MELD) was ≥20, and the benefit was highest at MELD 28 (0.172 additional life-years). The magnitude of clinical benefit was greater in UNOS regions with higher HCV-positive donor organ rates, that is, Regions 1, 2, 3, 10, and 11. Sensitivity analysis demonstrated that model outcomes were robust.

CONCLUSION

Transplanting HCV-positive livers into HCV-negative patients with preemptive DAA therapy could improve patient survival on the LT waiting list. Our analysis can help inform clinical trials and minimize patient harm. (Hepatology 2018;67:2085-2095).

Robotic Versus Open Renal Transplantation in Obese Patients: Protocol for a Cost-Benefit Markov Model Analysis

Background

Recent studies have reported a significant decrease in wound problems and hospital stay in obese patients undergoing renal transplantation by robotic-assisted minimally invasive techniques with no difference in graft function.

Objective

Due to the lack of cost-benefit studies on the use of robotic-assisted renal transplantation versus open surgical procedure, the primary aim of our study is to develop a Markov model to analyze the cost-benefit of robotic surgery versus open traditional surgery in obese patients in need of a renal transplant.

Methods

Electronic searches will be conducted to identify studies comparing open renal transplantation versus robotic-assisted renal transplantation. Costs associated with the two surgical techniques will incorporate the expenses of the resources used for the operations. A decision analysis model will be developed to simulate a randomized controlled trial comparing three interventional arms: (1) continuation of renal replacement therapy for patients who are considered non-suitable candidates for renal transplantation due to obesity, (2) transplant recipients undergoing open transplant surgery, and (3) transplant patients undergoing robotic-assisted renal transplantation. TreeAge Pro 2017 R1 TreeAge Software, Williamstown, MA, USA) will be used to create a Markov model and microsimulation will be used to compare costs and benefits for the two competing surgical interventions.

Results

The model will simulate a randomized controlled trial of adult obese patients affected by end-stage renal disease undergoing renal transplantation. The absorbing state of the model will be patients' death from any cause. By choosing death as the absorbing state, we will be able simulate the population of renal transplant recipients from the day of their randomization to transplant surgery or continuation on renal replacement therapy to their death and perform sensitivity analysis around patients' age at the time of randomization to determine if age is a critical variable for cost-benefit analysis or cost-effectiveness analysis comparing renal replacement therapy, robotic-assisted surgery or open renal transplant surgery. After running the model, one of the three competing strategies will result as the most cost-beneficial or cost-effective under common circumstances. To assess the robustness of the results of the model, a multivariable probabilistic sensitivity analysis will be performed by modifying the mean values and confidence intervals of key parameters with the main intent of assessing if the winning strategy is sensitive to rigorous and plausible variations of those values.

Conclusions

After running the model, one of the three competing strategies will result as the most cost-beneficial or cost-effective under common circumstances. To assess the robustness of the results of the model, a multivariable probabilistic sensitivity analysis will be performed by modifying the mean values and confidence intervals of key parameters with the main intent of assessing if the winning strategy is sensitive to rigorous and plausible variations of those values.

Exploratory search during directed navigation in C. elegans and Drosophila larva

Many organisms—from bacteria to nematodes to insect larvae—navigate their environments by biasing random movements. In these organisms, navigation in isotropic environments can be characterized as an essentially diffusive and undirected process. In stimulus gradients, movement decisions are biased to drive directed navigation toward favorable environments. How does directed navigation in a gradient modulate random exploration either parallel or orthogonal to the gradient? Here, we introduce methods originally used for analyzing protein folding trajectories to study the trajectories of the nematode Caenorhabditis elegans and the Drosophila larva in isotropic environments, as well as in thermal and chemical gradients. We find that the statistics of random exploration in any direction are little affected by directed movement along a stimulus gradient. A key constraint on the behavioral strategies of these organisms appears to be the preservation of their capacity to continuously explore their environments in all directions even while moving toward favorable conditions.

Cost-effectiveness of milk powder fortified with potassium to decrease blood pressure and prevent cardiovascular events among the adult population in China: a Markov model

OBJECTIVE

To model the long-term cost-effectiveness of consuming milk powder fortified with potassium to decrease systolic blood pressure (SBP) and prevent cardiovascular events.

DESIGN

A best case scenario analysis using a Markov model was conducted.

PARTICIPANTS

8.67% of 50-79 year olds who regularly consume milk in China, including individuals with and without a prior diagnosis of hypertension.

INTERVENTION

The model simulated the potential impact of a daily intake of two servings of milk powder fortified with potassium (+700 mg/day) vs the consumption of a milk powder without potassium fortification, assuming a market price equal to 0.99 international dollars (intl$; the consumption of a milk powder without potassium fortification, assuming a market price equal to intl$0.99 for the latter and to intl$1.12 for the first (+13.13%). Both deterministic and probabilistic sensitivity analyses were conducted to test the robustness of the results.

MAIN OUTCOME MEASURES

Estimates of the incidence of cardiovascular events and subsequent mortality in China were derived from the literature as well as the effect of increasing potassium intake on blood pressure. The incremental cost-effectiveness ratio (ICER) was used to determine the cost-effectiveness of a milk powder fortified with potassium taking into consideration the direct medical costs associated with the cardiovascular events, loss of working days and health utilities impact.

RESULTS

With an ICER equal to int$4711.56 per QALY (quality-adjusted life year) in the best case scenario and assuming 100% compliance, the daily consumption of a milk powder fortified with potassium shown to be a cost-effective approach to decrease SBP and reduce cardiovascular events in China. Healthcare savings due to prevention would amount to intl$8.41 billion. Sensitivity analyses showed the robustness of the results.

CONCLUSION

Together with other preventive interventions, the consumption of a milk powder fortified with potassium could represent a cost-effective strategy to attenuate the rapid rise in cardiovascular burden among the 50-79 year olds who regularly consume milk in China.

A policy model of cardiovascular disease in moderate-to-advanced chronic kidney disease

OBJECTIVE

To present a long-term policy model of cardiovascular disease (CVD) in moderate-to-advanced chronic kidney disease (CKD).

METHODS

A Markov model with transitions between CKD stages (3B, 4, 5, on dialysis, with kidney transplant) and cardiovascular events (major atherosclerotic events, haemorrhagic stroke, vascular death) was developed with individualised CKD and CVD risks estimated using the 5 years' follow-up data of the 9270 patients with moderate-to-severe CKD in the Study of Heart and Renal Protection (SHARP) and multivariate parametric survival analysis. The model was assessed in three further CKD cohorts and compared with currently used risk scores.

RESULTS

Higher age, previous cardiovascular events and advanced CKD were the main contributors to increased individual disease risks. CKD and CVD risks predicted by the state-transition model corresponded well to risks observed in SHARP and external cohorts. The model's predictions of vascular risk and progression to end-stage renal disease were better than, or comparable to, those produced by other risk scores. As an illustration, at age 60-69 years, projected survival for SHARP participants in CKD stage 3B was 13.5 years (10.6 quality-adjusted life years (QALYs)) in men and 14.8 years (10.7 QALYs) in women. Corresponding projections for participants on dialysis were 7.5 (5.6 QALYs) and 7.8 years (5.4 QALYs). A non-fatal major atherosclerotic event reduced life expectancy by about 2 years in stage 3B and by 1 year in dialysis.

CONCLUSIONS

The SHARP CKD-CVD model is a novel resource for evaluating health outcomes and cost-effectiveness of interventions in CKD.

TRIAL REGISTRATION NUMBER

NCT00125593 and ISRCTN54137607; Post-results.

An economic analysis of high-dose imatinib, dasatinib, and nilotinib for imatinib-resistant chronic phase chronic myeloid leukemia in China: A CHEERS-compliant article

BACKGROUND

The aim of the study was to test the cost-effectiveness of dasatinib compared to high-dose imatinib and nilotinib in Chinese patients who were diagnosed with imatinib-resistant chronic myeloid leukemia in the chronic phase (CML-CP).

METHODS

A Markov model combined with clinical effectiveness, utility, and cost data was used. The sensitivity analyses were conducted to determine the robustness of the model outcomes. The impact of patient assistance programs (PAPs) was assessed.

RESULTS

Treatment with dasatinib is expected to produce 3.65, 0.59, and 0.15 more quality-adjusted life years (QALYs) in comparison with high-dose imatinib (600 and 800 mg) and nilotinib, respectively. When a PAP was available, dasatinib yielded an incremental cost of $16,417 per QALY compared to imatinib (600 mg) and was cost-saving compared to imatinib (800 mg) and nilotinib.

CONCLUSION

When PAP is available in the Chinese setting, dasatinib is likely to be a cost-effective strategy for patients with CML-CP standard-dose imatinib resistance. The results should be carefully explained due to the assumptions and limitations used in the study.

Cost-effectiveness of Catheter Ablation Versus Antiarrhythmic Drug Therapy for the Treatment of Atrial Fibrillation: A Canadian Perspective

Background: Atrial fibrillation (AF) affects approximately 350,000 Canadians and has an estimated annual economic burden exceeding $800 million dollars. Anti-arrhythmic drug (AAD) therapy and catheter ablation (CA) are the two common treatments for paroxysmal AF. However, the upfront costs of CA are quite substantial. Objective: The objective of this study was to assess the cost-effectiveness of CA compared to AAD for AF based on community practice. Methods: A Markov simulation model was developed for a hypothetical cohort of 55-year-old patients with paroxysmal AF and a low stroke risk. Patients received either CA or AAD. Costs and quality-adjusted life years (QALYs) were computed over lifetime, 10-year, and 5-year time horizons. Model inputs were obtained from a large, prospectively collected, single-center Canadian registry and augmented with the published literature, using Canadian cost estimates for disease states. Threshold values of $25,000, $50,000, and $100,000 per QALY, respectively, were used to determine cost-effectiveness. All costs were expressed in 2012 Canadian dollars. Results: The incremental cost-effectiveness ratio for CA versus AAD therapy was $1,228, $22,879, and $63,647 for the lifetime, 10-year, and 5-year time horizons, respectively. Over a lifetime horizon, the probability of achieving cost-effectiveness was 100% for all 3 cost per QALY thresholds. The 10-year probability of achieving cost-effectiveness was 74%, 100%, and 100% at the $25,000, $50,000, and $100,000 thresholds, respectively. The 5-year probability of achieving cost-effectiveness was 0%, 0.9%, and 100% at the 3 cost per QALY thresholds. Results were most sensitive to time horizon, probability of repeat AF ablation, and stroke rate. Conclusions: From the perspective of the Canadian Healthcare system, CA is a potentially cost-effective treatment compared to AAD therapy in a low stroke risk population using real-world data when examining a time horizon of greater than 5 years.

Cost-effectiveness of currently recommended direct-acting antiviral treatments in patients infected with genotypes 1 or 4 hepatitis C virus in the US

OBJECTIVE

This study compared the cost-effectiveness of direct-acting antiviral therapies currently recommended for treating genotypes (GT) 1 and 4 chronic hepatitis C (CHC) patients in the US.

METHODS

A cost-effectiveness analysis of treatments for CHC from a US payer's perspective over a lifelong time horizon was performed. A Markov model based on the natural history of CHC was used for a population that included treatment-naïve and -experienced patients. Treatment alternatives considered for GT1 included ombitasvir/paritaprevir/ritonavir + dasabuvir ± ribavirin (3D ± R), sofosbuvir + ledipasvir (SOF/LDV), sofosbuvir + simeprevir (SOF + SMV), simeprevir + pegylated interferon/ribavirin (SMV + PR) and no treatment (NT). For GT4 treatments, ombitasvir/paritaprevir/ritonavir + ribavirin (2D + R), SOF/LDV and NT were compared. Transition probabilities, utilities and costs were obtained from published literature. Outcomes included rates of compensated cirrhosis (CC), decompensated cirrhosis (DCC), hepatocellular carcinoma (HCC) and liver-related death (LrD), total costs, life-years and quality-adjusted life-years (QALYs). Costs and QALYs were used to calculate incremental cost-effectiveness ratios.

RESULTS

In GT1 patients, 3D ± R and SOF-containing regimens have similar long-term outcomes; 3D ± R had the lowest lifetime risks of all liver disease outcomes: CC = 30.2%, DCC = 5.0 %, HCC = 6.8%, LT = 1.9% and LrD = 9.2%. In GT1 patients, 3D ± R had the lowest cost and the highest QALYs. As a result, 3D ± R dominated these treatment options. In GT4 patients, 2D + R had lower rates of liver morbidity and mortality, lower cost and more QALYs than SOF/LDV and NT.

LIMITATIONS

While the results are based on input values, which were obtained from a variety of heterogeneous sources-including clinical trials, the findings were robust across a plausible range of input values, as demonstrated in probabilistic sensitivity analyses.

CONCLUSIONS

Among currently recommended treatments for GT1 and GT4 in the US, 3D ± R (for GT1) and 2D + R (for GT4) have a favorable cost-effectiveness profile.

Clinical and economic benefits of extended treatment with apixaban for the treatment and prevention of recurrent venous thromboembolism in Canada

Background and objective Venous thromboembolism (VTE) is associated with long-term clinical and economic burden. Clinical guidelines generally recommend at least 3 months of anticoagulation, but, in clinical practice, concerns over bleeding risk often limit extended treatment. Apixaban was studied for extended VTE treatment in the AMPLIFY-EXT trial, demonstrating superiority to placebo in VTE reduction without increasing risk of major bleeding. This study assessed the long-term clinical and economic benefits of extending treatment with apixaban when clinical equipoise exists compared to standard of care with enoxaparin/warfarin and other novel oral anti-coagulants (NOACs) for the treatment and prevention of recurrent VTE in Canada. Methods A Markov model was developed to follow patients with VTE over their lifetimes. Efficacy and safety for apixaban and enoxaparin/warfarin were based on AMPLIFY and AMPLIFY-EXT, while relative efficacy to other NOACs was synthesized by network meta-analysis (NMA). Dosages for NOACs and enoxaparin/warfarin were based on their respective trials and were given up to 18 months and up to 6 months, followed by no treatment, respectively. Patient quality adjusted life years (QALYs) were based on published studies, and costs for resource utilization were from a Ministry of Health perspective, expressed as 2014 CAD ($). Results Extended treatment with apixaban compared to enoxaparin/warfarin resulted in fewer recurrent VTEs, VTE-related deaths, and bleeding events, but at slightly increased cost. The incremental cost-effectiveness ratio was $4828 per QALY gained. Compared to other NOACs, apixaban had the fewest bleeding events, similar recurrent VTE events, and the lowest overall cost, which was driven by the strong bleeding profile. In scenario analyses of acute and lifetime treatments, apixaban was cost-effective against all strategies. Conclusions Extended treatment with apixaban can offer substantial clinical benefits and is a cost-effective alternative to enoxaparin/warfarin and other NOACs.

Stochastic modeling of central apnea events in preterm infants

A near-ubiquitous pathology in very low birth weight infants is neonatal apnea, breathing pauses with slowing of the heart and falling blood oxygen. Events of substantial duration occasionally occur after an infant is discharged from the neonatal intensive care unit (NICU). It is not known whether apneas result from a predictable process or from a stochastic process, but the observation that they occur in seemingly random clusters justifies the use of stochastic models. We use a hidden-Markov model to analyze the distribution of durations of apneas and the distribution of times between apneas. The model suggests the presence of four breathing states, ranging from very stable (with an average lifetime of 12 h) to very unstable (with an average lifetime of 10 s). Although the states themselves are not visible, the mathematical analysis gives estimates of the transition rates among these states. We have obtained these transition rates, and shown how they change with post-menstrual age; as expected, the residence time in the more stable breathing states increases with age. We also extrapolated the model to predict the frequency of very prolonged apnea during the first year of life. This paradigm-stochastic modeling of cardiorespiratory control in neonatal infants to estimate risk for severe clinical events-may be a first step toward personalized risk assessment for life threatening apnea events after NICU discharge.

Cost-effectiveness analysis of a vaccination program for the prevention of herpes zoster and post-herpetic neuralgia in adults aged 50 and over in Germany

Herpes zoster (HZ; shingles) is a common viral disease that affects the nerves and surrounding skin causing a painful dermatomal rash and leading to debilitating complications such as, mainly, post-herpetic neuralgia (PHN). Currently, there is no effective treatment for HZ and PHN. The objective of this study was to assess the cost-effectiveness of a HZ vaccination program in Germany. An existing Markov Model was adapted to the German healthcare setting to compare a vaccination policy to no vaccination on a lifetime time-horizon, considering 2 scenarios: vaccinating people starting at the age of 50 or at the age of 60 years, from the perspective of the statutory health insurance (SHI) and the societal perspective. According to the perspective, vaccinating 20% of the 60+ German population resulted in 162,713 to 186,732 HZ and 31,657 to 35,793 PHN cases avoided. Corresponding incremental cost-effectiveness ratios (ICER) were 39,306 €/QALY from the SHI perspective and 37,417 €/QALY from a societal perspective. Results for the 50+ German population ranged from 336,468 to 394,575 HZ and from 48,637 to 56,087 PHN cases avoided from the societal perspective. Corresponding ICER were 39,782 €/QALY from a SHI perspective and 32,848 €/QALY from a societal perspective. Sensitivity analyses showed that results are mainly impacted by discount rates, utility values and use of alternative epidemiological data.The model indicated that a HZ vaccination policy in Germany leads to significant public health benefits and could be a cost-effective intervention. The results were robust and consistent with local and international existing literature.

Cost-effectiveness of new antiviral regimens for treatment-naïve U.S. veterans with hepatitis C

Recently approved, interferon-free medication regimens for treating hepatitis C are highly effective, but extremely costly. We aimed to identify cost-effective strategies for managing treatment-naïve U.S. veterans with new hepatitis C medication regimens. We developed a Markov model with 1-year cycle length for a cohort of 60-year-old veterans with untreated genotype 1 hepatitis C seeking treatment in a typical year. We compared using sofosbuvir/ledipasvir or ombitasvir/ritonavir/paritaprevir/dasabuvir to treat: (1) any patient seeking treatment; (2) only patients with advanced fibrosis or cirrhosis; or (3) patients with advanced disease first and healthier patients 1 year later. The previous standard of care, sofosbuvir/simeprevir or sofosbuvir/pegylated interferon/ribavirin, was included for comparison. Patients could develop progressive fibrosis, cirrhosis, or hepatocellular carcinoma, undergo transplantation, or die. Complications were less likely after sustained virological response. We calculated the incremental cost per quality-adjusted life year (QALY) and varied model inputs in one-way and probabilistic sensitivity analyses. We used the Veterans Health Administration perspective with a lifetime time horizon and 3% annual discounting. Treating any patient with ombitasvir-based therapy was the preferred strategy ($35,560; 14.0 QALYs). All other strategies were dominated (greater costs/QALY gained than more effective strategies). Varying treatment efficacy, price, and/or duration changed the preferred strategy. In probabilistic sensitivity analysis, treating any patient with ombitasvir-based therapy was cost-effective in 70% of iterations at a $50,000/QALY threshold and 65% of iterations at a $100,000/QALY threshold.

CONCLUSION

Managing any treatment-naïve genotype 1 hepatitis C patient with ombitasvir-based therapy is the most economically efficient strategy, although price and efficacy can impact cost-effectiveness. It is economically unfavorable to restrict treatment to patients with advanced disease or use a staged treatment strategy. (Hepatology 2016;63:428-436).

Subgroup Economic Evaluation of Radiotherapy for Breast Cancer After Mastectomy

BACKGROUND

A recent meta-analysis by the Early Breast Cancer Trialists' Collaborative Group found significant improvements achieved by postmastectomy radiotherapy (PMRT) for patients with breast cancer with 1 to 3 positive nodes (pN1-3). It is unclear whether PMRT is cost-effective for subgroups of patients with positive nodes.

OBJECTIVE

To determine the cost-effectiveness of PMRT for subgroups of patients with breast cancer with positive nodes.

METHODS

A semi-Markov model was constructed to estimate the expected lifetime costs, life expectancy, and quality-adjusted life-years for patients receiving or not receiving radiation therapy. Clinical and health utilities data were from meta-analyses by the Early Breast Cancer Trialists' Collaborative Group or randomized clinical trials. Costs were estimated from the perspective of the Chinese society. One-way and probabilistic sensitivity analyses were performed.

FINDINGS

The incremental cost-effective ratio was estimated as $7984, $4043, $3572, and $19,021 per quality-adjusted life-year for patients with positive nodes (pN+), patients with pN1-3, patients with pN1-3 who received systemic therapy, and patients with >4 positive nodes (pN4+), respectively. According to World Health Organization recommendations, these incremental cost-effective ratios were judged as cost-effective. However, the results of one-way sensitivity analyses suggested that the results were highly sensitive to the relative effectiveness of PMRT (rate ratio).

IMPLICATIONS

We determined that the results were highly sensitive to the rate ratio. However, the addition of PMRT for patients with pN1-3 in China has a reasonable chance to be cost-effective and may be judged as an efficient deployment of limited health resource, and the risk and uncertainty of PMRT are relatively greater for patients with pN4+.

Cost-effectiveness analysis of axitinib through a probabilistic decision model

INTRODUCTION

The Oncology field is characterised by a steady increase in demand and a consistent launching of innovative and expensive products. Therefore, cost-effectiveness analysis can contribute as a significant decision-making tool by elucidating the most economically efficient ways to satisfy compelling health needs.

AREAS COVERED

The scope of this study is to estimate the cost-effectiveness of axitinib versus sorafenib, for the second-line treatment of renal cell carcinoma. A literature review for evidence synthesis was performed and a probabilistic Markov Model was employed to simulate disease progression. This study will also assess Value of Information.

EXPERT OPINION

Compared to sorafenib, axitinib resulted in an incremental cost of 87,936 euro per quality adjusted life year. The probability of axitinib to being cost-effective at the willingness-to-pay threshold of 60,000 euro was 13%, while the corresponding probability of being cost-effective at the highest recommended willingness-to-pay threshold of 100,000 euro was 69.9%. Uncertainty was primarily attributed to the price of the product, the utility values, the progression-free survival and to a lesser degree to the overall survival. Axitinib can be considered as a cost-effective therapeutic option for second-line treatment of renal cell carcinoma.

Cost-effectiveness of smoking cessation treatment initiated during psychiatric hospitalization: analysis from a randomized, controlled trial

OBJECTIVE

We examined the cost-effectiveness of smoking cessation treatment for psychiatric inpatients.

METHOD

Smokers, regardless of intention to quit, were recruited during psychiatric hospitalization and randomized to receive stage-based smoking cessation services or usual aftercare. Smoking cessation services, quality of life, and biochemically verified abstinence from cigarettes were assessed during 18 months of follow-up. A Markov model of cost-effectiveness over a lifetime horizon was constructed using trial findings and parameters obtained in a review of the literature on quit and relapse rates and the effect of smoking on health care cost, quality of life, and mortality.

RESULTS

Among 223 smokers randomized between 2006 and 2008, the mean cost of smoking cessation services was $189 in the experimental treatment group and $37 in the usual care condition (P < .001). At the end of follow-up, 18.75% of the experimental group was abstinent from cigarettes, compared to 6.80% abstinence in the usual care group (P < .05). The model projected that the intervention added $43 in lifetime cost and generated 0.101 additional quality-adjusted life-years (QALYs), an incremental cost-effectiveness ratio of $428 per QALY. Probabilistic sensitivity analysis found the experimental intervention was cost-effective against the acceptance criteria of $50,000/QALY in 99.0% of the replicates.

CONCLUSIONS

A cessation intervention for smokers identified in psychiatric hospitalization did not result in higher mental health care costs in the short-run and was highly cost-effective over the long-term. The stage-based intervention was a feasible and cost-effective way of addressing the high smoking prevalence in persons with serious mental illness.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00136812.

Cost-effectiveness of sofosbuvir-based treatments for chronic hepatitis C in the US

BACKGROUND

The standard care of treatment of interferon plus ribavirin (plus protease inhibitor for genotype 1) are effective in 50 % to 70 % of patients with CHC. Several new treatments including Harvoni, Olysio + Sovaldi, Viekira Pak, Sofosbuvir-based regimens characterized with potent inhibitors have been approved by the Food and Drug Administration (FDA) providing more options for CHC patients. Trials have shown that the new treatments increased the rate to 80% to 95%, though with a substantial increase in cost. In particular, current market pricing of a 12-week course of sofosbuvir is approximately US$84,000. We determine the cost-effectiveness of new treatments in comparison with the standard care of treatments.

METHODS

A Markov simulation model of CHC disease progression is used to evaluate the cost-effectiveness of different treatment strategies based on genotype. The model calculates the expected lifetime medical costs and quality adjusted life years (QALYs) of hypothetical cohorts of identical patients receiving certain treatments. For genotype 1, we compare: (1) peginterferon + ribavirin + telaprevir for 12 weeks, followed by 12 or 24 weeks treatment of peginterferon + ribavirin dependent on HCV RNA level at week 12; (2) Harvoni treatment, 12 weeks; (3) Olysio + Sovaldi, 12 weeks for patients without cirrhosis, 24 weeks for patients with cirrhosis; (4) Viekira Pak + ribavirin, 12 weeks for patients without cirrhosis, 24 weeks for patients with cirrhosis; (5) sofosbuvir + peginterferon + ribavirin, 12 weeks for patients with or without cirrhosis. For genotypes 2 and 3, treatment strategies include: (1) peginterferon + ribavirin, 24 weeks for treatment-naïve patients; (2) sofosbuvir + ribavirin, 12 weeks for patients with genotype 2, 24 weeks for genotype 3; (3) peginterferon + ribavirin as initial treatment, 24 weeks for patients with genotype 2/3, follow-up treatment with sofosbuvir + ribavirin for 12/16 weeks are performed on non-responders and relapsers.

RESULTS

Viekira Pak is cost-effective for genotype 1 patients without cirrhosis, whereas Harvoni is cost-effective for genotype 1 patients with cirrhosis. Sofosbuvir-based treatments for genotype 1 in general are not cost-effective due to its substantial high costs. Two-phase treatments with 12-week and 16-week follow-ups are cost-effective for genotype 3 patients and for genotype 2 patients with cirrhosis. The results were shown to be robust over a broad range of parameter values through sensitivity analysis.

CONCLUSIONS

For genotype 1, sofosbuvir-based treatments are not cost-effective compared to Viekira Pak and Harvoni, although a 30% reduction in sofosbuvir price would change this result. Sofosbuvir + ribavirin are cost-effective as second-phase treatments following peginterferon + ribavirin initial treatment for genotypes 2 and 3. However, there is limited data on sofosbuvir-involved treatment, and the results obtained in this study must be interpreted within the model assumptions.

Cost-utility of cognitive behavioral therapy for low back pain from the commercial payer perspective

STUDY DESIGN

Markov cost-utility model.

OBJECTIVE

To evaluate the cost-utility of cognitive behavioral therapy (CBT) for the treatment of persistent nonspecific low back pain (LBP) from the perspective of US commercial payers.

SUMMARY OF BACKGROUND DATA

CBT is widely deemed clinically effective for LBP treatment. The evidence is suggestive of cost-effectiveness.

METHODS

We constructed and validated a Markov intention-to-treat model to estimate the cost-utility of CBT, with 1-year and 10-year time horizons. We applied likelihood of improvement and utilities from a randomized controlled trial assessing CBT to treat LBP. The trial randomized subjects to treatment but subjects freely sought health care services. We derived the cost of equivalent rates and types of services from US commercial claims for LBP for a similar population. For the 10-year estimates, we derived recurrence rates from the literature. The base case included medical and pharmaceutical services and assumed gradual loss of skill in applying CBT techniques. Sensitivity analyses assessed the distribution of service utilization, utility values, and rate of LBP recurrence. We compared health plan designs. Results are based on 5000 iterations of each model and expressed as an incremental cost per quality-adjusted life-year.

RESULTS

The incremental cost-utility of CBT was $7197 per quality-adjusted life-year in the first year and $5855 per quality-adjusted life-year over 10 years. The results are robust across numerous sensitivity analyses. No change of parameter estimate resulted in a difference of more than 7% from the base case for either time horizon. Including chiropractic and/or acupuncture care did not substantively affect cost-effectiveness. The model with medical but no pharmaceutical costs was more cost-effective ($5238 for 1 yr and $3849 for 10 yr).

CONCLUSION

CBT is a cost-effective approach to manage chronic LBP among commercial health plans members. Cost-effectiveness is demonstrated for multiple plan designs.

LEVEL OF EVIDENCE

2.

Early health economic evaluation of the future potential of next generation artificial vision systems for treating blindness in Germany

The next generation of artificial vision devices (AVDs), which is currently developed in pre-clinical settings, has the potential to improve the vision of blind patients with retinitis pigmentosa (RP) in a manner that they will be categorized as visual impaired but no more as blind. This unprecedented vision improvement will result in a mentionable quality of life gain which poses the question at which costs the next generation AVDs are to be regarded as cost-effective, from a German healthcare payer perspective. In order to answer this research question a Markov model was developed to simulate and to compare the costs and effects of next generation AVDs versus best supportive care (BSC). Applying the base case settings resulted in incremental costs of 107,925, in 2.03 incremental quality-adjusted life years (QALYs) and in a cost-effectiveness ratio of 53,165 per QALY gained. Probabilistic and deterministic sensitivity analyses as well as scenario analyses for the effect size and the AVD costs were performed in order to investigate the robustness of results. In these scenario analyses a strong variation of the cost-effectiveness results was obtained ranging from 23,512 (best case) to 176,958 (worst case) per QALY gained by AVD therapy. This early health economic evaluation has to handle with three main uncertainty factors: the effect size of next generation AVDs, the costs of next generation AVDs and the WTP threshold that might be applied in RP patients, which reflect the main limitations of the presented assessment. In conclusion the presented early cost-effectiveness evaluation has obtained that next generation AVDs have the potential to be a cost-effective therapy option in patients with RP in Germany. The innovative nature, the high unmet medical need and the expected unprecedented efficacy of next generation AVDs will highly likely lead to the case that even relatively high incremental cost-effectiveness ratios, that have been obtained when simulating various effect and pricing scenarios, will be regarded as acceptable from a German healthcare payer perspective.

Cost effectiveness of primary care referral to a commercial provider for weight loss treatment, relative to standard care: a modelled lifetime analysis

BACKGROUND

Because of the high prevalence of overweight and obesity, there is a need to identify cost-effective approaches for weight loss in primary care and community settings.

OBJECTIVE

To evaluate the long-term cost effectiveness of a commercial weight loss programme (Weight Watchers) (CP) compared with standard care (SC), as defined by national guidelines.

METHODS

A Markov model was developed to calculate the incremental cost-effectiveness ratio (ICER), expressed as the cost per quality-adjusted life year (QALY) over the lifetime. The probabilities and quality-of-life utilities of outcomes were extrapolated from trial data using estimates from the published literature. A health sector perspective was adopted.

RESULTS

Over a patient's lifetime, the CP resulted in an incremental cost saving of AUD 70 per patient, and an incremental 0.03 QALYs gained per patient. As such, the CP was found to be the dominant treatment, being more effective and less costly than SC (95% confidence interval: dominant to 6225 per QALY). Despite the CP delaying the onset of diabetes by ∼10 months, there was no significant difference in the incidence of type 2 diabetes, with the CP achieving <0.1% fewer cases than SC over the lifetime.

CONCLUSION

The modelled results suggest that referral to community-based interventions may provide a highly cost-effective approach for those at high risk of weight-related comorbidities.

A gating model for wildtype and R1448H Nav1.4 channels in paramyotonia

We studied the consequences of the Nav1.4 mutation R1448H that is situated in the fourth voltage sensor of the channel and causes paramyotonia, a cold-induced myotonia followed by weakness. Previous work showed that the mutation uncouples inactivation from activation. We measured whole-cell Na(+) currents at 10, 15, 20, and 25°C using HEK293 cells stably transfected with wildtype (WT) and R1448H Na(+) channels. A Markov model was developed the parameters of which reproduced the data measured on WT and R1448H channels in the whole voltage and temperature range. It required an additional transient inactivated state and an additional closed-state inactivation transition not previously described. The model was used to predict single-channel properties, free energy barriers and temperature dependence of rates. It allowed us to draw the following conclusions: i) open-state inactivation results from a two-step process; ii) the channel re-openings that cause paramyotonia originate from enhanced deactivation/reactivation and not from destabilized inactivation; iii) the closed-state inactivation of R1448H is strikingly enhanced. We assume that latter explains the episodic weakness following cold-induced myotonia.