David Epstein

Background: Peripheral arterial disease is a major cause of the development of diabetic foot ulcers, lower limb amputation and mortality in patients with diabetes. Diagnosing peripheral arterial disease is of clinical importance but is difficult in this cohort of patients. Several diagnostic bedside tests exist, but there is uncertainty as to which is the most accurate. Objective(s): To determine the diagnostic accuracy of five index tests (audible waveform assessment, visual waveform assessment, toe–brachial pressure index, ankle–brachial pressure index and exercise ankle–brachial pressure index) for the diagnosis of peripheral arterial disease in patients with diabetes as determined by a reference test (computed tomography angiography or magnetic resonance angiography). In selected sites, to evaluate the performance of a sixth test, the Podiatry Ankle Duplex scan, a new point-of-care duplex ultrasound scan. Design and methods: Prospective multicentre diagnostic accuracy study. Setting: Primary (general practice and community clinics) and secondary care National Health Service hospitals (inpatient and outpatient) in the United Kingdom. Participants: Patients were eligible for inclusion if they were aged ≥ 18 years and had a known history of diabetes. Exclusion criteria included contraindications to computed tomography angiography or magnetic resonance angiography, if their peripheral arterial disease status was known on imaging, or they had a known history of peripheral arterial disease intervention. Interventions: Participants underwent all bedside tests (Podiatry Ankle Duplex scan performed in three centres only), which were performed in a logical sequence to reduce the risk of bias. The reference scan was to be performed within 6 weeks of the index tests. Main outcome measures: The primary outcome measure of diagnostic performance is test sensitivity. Secondary outcomes included specificity, likelihood ratios, predictive values and diagnostic odds ratio, as well as patient acceptability of tests, technical success and health economic outcomes. Results: Based on the 573 reference tests performed, 222 (39%) participants had evidence of peripheral arterial disease. All routinely used index tests showed relatively low sensitivities: audible waveform 36%, 99% confidence interval 27% to 45%; visual waveform 42%, confidence interval 33% to 51%; toe–brachial pressure index 55%, confidence interval 46% to 64%; ankle–brachial pressure index 41%, confidence interval 32% to 50%; and exercise ankle–brachial pressure index 41%, confidence interval 31% to 51%. The Podiatry Ankle Duplex scan had a higher sensitivity 89%, confidence interval 74% to 100%, as compared to all other index tests. Limitations: A large proportion of reference scans were performed outside the 6-week time window (45%), although peripheral arterial disease is a chronic condition and is unlikely to have developed/progressed in the time frame. Additionally, the peripheral arterial disease prevalence was lower than anticipated during study design (39% vs. 50%). Lastly, despite efforts to standardise assessment and minimise bias, there is the possibility that one test may have influenced the interpretation of others. Conclusions: Index tests used routinely in clinical practice for diagnosing peripheral arterial disease in patients with diabetes showed poor diagnostic accuracy for peripheral arterial disease and should not be recommended for diagnosing peripheral arterial disease in this population. Future work: A review of peripheral arterial disease diagnostic testing in patients with diabetes should be undertaken. It may be necessary to perform more reliable imaging, such as full lower limb duplex ultrasound as a first-line diagnostic test. Funding: This synopsis presents independent research funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme as award number NIHR131855.

The development of health technologies involves complex, costly, and risky investments, with significant contributions from both public and private sectors. Recent EU pharmaceutical directives propose transparency on public funding to aid pricing negotiations and affordability. However, questions remain regarding how public investments should be measured and their influence on pricing and reimbursement (P&R) decisions. In this paper, we characterise public sector institutions as "payers," "R&D investors," and "regulators". Through a myriad of agencies and decisions, these institutions directly, indirectly or sometime unexpectedly influence risk and return on private research and development (R&D) through P&R, direct investments, and regulatory policy. P&R decisions by payers for innovative therapies influence risk and expected return of future R&D. Value-based pricing offers a more reliable signal of payers' priorities than cost-plus or (international) reference pricing. For greatest impact, public R&D investment should be directed to areas where markets are deficient, such as basic science, translational research, real-world studies, and towards emerging fields like AI and gene editing that will play an increasing role in healthcare and drug development. Applied R&D should be conducted on a financially sustainable basis. Licensing arrangements can be used to recover those investments, while promoting spillover benefits to wider society. Market access regulators are aware of the need for scrupulous transparency and neutrality, but other public sector actors (payers and R&D investors) also must recognise their policies affect the level playing field.

Although the criteria that support reimbursement decisions for medicines are often set by legislation, as is the case in Spain, in many cases neither the definition nor the measurement methods for these criteria are provided. Our goal was to elicit the views of a large sample of Spanish technical specialists on how to evaluate each one of the criteria that inform pricing and reimbursement decisions in Spain. Professionals from various stakeholder groups involved in health economics, health technology assessment, and industry participated in a survey. Participants recommended that reimbursement decisions should take specific account of unmet medical need and rare diseases. Health benefit should be measured using quality-adjusted life-years. There should be an explicit cost-effectiveness threshold, and this threshold should take account of population groups and special situations.

The new European Medical Device Regulation has raised the bar for the clinical evaluation of medical devices to gain marketing authorization by Notified Bodies (NBs) regarding certificates of conformity in Europe. Restrictions applied for High-risk medical devices (HRMD) may require further evidence generation. Some other jurisdictions apply similar schemes that may be useful to the European Union. This systematic review focused on extracting lessons from similar schemes worldwide to the European context. A systematic review of peer-reviewed and gray literature was performed based on 'Device approval' and 'conditional approval' keywords. Databases such as Medline, Embase, and WoS retrieved documents assessed with the AMSTAR-2 checklist. A descriptive and narrative analysis was conducted detailed in CRD42023431233 - PROSPERO. We obtained eight documents where conditional approvals for High-risk medical devices in the United States of America, China, and Canada were subject to generate further evidence. In Europe, NBs impose restrictions or limitations to certificates of conformity instead. Further development of policies, supporting access to HRMD subject to further evidence generation, would help Europe in further defining the appropriate situations for the application of determined regulatory routes, to enhance access to HRMD with promising evidence and further evidence development. PROSPERO (CRD42023431233).

Introduction Abemaciclib is an oral inhibitor of cyclin-dependent kinases 4 and 6 (CDK4/6). Data from the clinical trial monarchE (2023) showed improved survival from invasive disease. The aim of the present article was to conduct an economic assessment of adjuvant treatment with abemaciclib in women with luminal, HER2- and node-positive breast cancer. Methods A Markov model was constructed with four mutually exclusive health states (disease-free, local recurrence, distal recurrence and death). Analyses were based on the clinical trial monarchE which compared an intervention group (abemaciclib + hormone therapy [HT]) with HT alone. The effectiveness measure used was quality-adjusted life years (QALY), with unit costs and utilities being obtained from existing literature. The incremental cost–utility ratio (ICUR) was used to compare the two treatment strategies. Results Total costs were €98,765 and €17,935 for the abemaciclib plus HT group and the HT alone group, respectively. The health outcome was 10.076QALY for the intervention group and 9.495QALY for the control group, with the ICUR being€139,173/QALY. Conclusion Despite the significant gains of abemaciclib as adjuvant treatment in terms of progression-free survival, this treatment is not cost-effective for the Spanish National Health System at published prices. It may be cost-effective with an appropriate discount on the official price.

Homocystinuria (HCU) is a rare metabolic disease that affects many organs, including the eyes. Aims: to assess visual functions, ocular characteristics, visual quality of life and time from the onset of ocular manifestations to HCU-diagnosis in patients with HCU. Eighteen patients underwent ophthalmological examinations and visual quality of life questionnaires. Best corrected decimal visual acuity was median 1.0 (range amaurosis - 1.3) right eye and 1.0 (range amaurosis -1.3) left eye. Five patients presented with severe myopia as first HCU manifestation, duration to HCU diagnosis was mean 13.6 years (range 2-25). Two patients had suffered ectopia lentis as first HCU manifestation, HCU diagnosis was established mean 8.0 years (range 7-9) later. One patient had suffered both from thrombosis and ectopia lentis prior to diagnosis. Another four patients suffered thromboembolic events before diagnosis. Median VFQ-25 composite score was 93 (68-98). The prevalence of myopia, ectopia lentis and monocular blindness was high in HCU-patients, which was reflected in their visual quality of life. Diagnosis was often delayed after the first ocular manifestation, increasing the risk of other severe non-ocular complications.

INES (INteractive model for Extrapolation of Survival and cost) provides an open-access tool powered by R that implements three-state partitioned survival models (PSM). This article describes the properties of the tool, and the situations where INES may or may not be suitable. INES is designed to be used by investigators or healthcare professionals who have a good grasp of the principles of economic evaluation and understand the strengths and weaknesses of partitioned survival models, but are not sufficiently familiar with a statistical package such as Excel or R to be able to construct and test a de-novo PSM themselves. INES is delivered to the user via a batch file. Once downloaded to the user’s hard drive, it interacts with the user via a portable version of R with web interactivity built in Shiny. INES requires absolutely no knowledge of R and the user does not need to have R or any of its dependences installed. Hence the user will deal with a standalone Shiny app. Inputs (digitalized survival curves, unit costs, posology, hazard ratios, discount rate) can be uploaded from a template spreadsheet. The INES application provides a seamlessly integrated package for estimating a set of parametric hazard functions for progression free and overall survival, selecting an appropriate function from this menu, and applying this as an input to a PSM to calculate mean costs and quality-adjusted life years. Examples are given that may serve as a tutorial. INES offers a rapid, flexible, robust and transparent tool for parametric survival analysis and calculating a PSM that can be used in many different contexts.

Background: Peripheral arterial disease is common and associated with increased cardiovascular morbidity and mortality. While patients with peripheral arterial disease are known to benefit from supervised exercise therapy, it is not always available. Neuromuscular electrical stimulation devices may offer a similar benefit. A randomised controlled trial was required to ascertain whether such devices can benefit patients who receive supervised exercise therapy and those who do not. Objective(s): The primary objective was to assess the mean difference in absolute walking distance at 3 months in intermittent claudication patients receiving either a neuromuscular electrical stimulation device and local standard care (intervention), or local standard care alone (control). Design: A pragmatic, multicentre, randomised controlled trial stratified by centre. Setting: Secondary-care National Health Service hospitals in the United Kingdom. Participants: Patients aged ≥18 years, with a diagnosis of intermittent claudication according to the Edinburgh Claudication Questionnaire and ankle–brachial pressure index (or stress test), without contraindications to neuromuscular electrical stimulation were deemed eligible to partake. Interventions: Participants were randomised 1 : 1 to either local standard care or local standard care and neuromuscular electrical stimulation. Due to the nature of the intervention, it was unfeasible to blind the research nurse or participant to the study allocation. Main outcome measures: The primary outcome measure was absolute walking distance measured by treadmill testing at 3 months. Secondary outcomes included change in initial claudication distance, quality of life, compliance with interventions and haemodynamic assessments. Results: Two hundred patients underwent randomisation, with 160 patients having analysable primary outcome data for the intention-to-treat analysis intervention (n = 80); control (n = 80). As the data were right-censored, a Tobit regression model was used to analyse the primary outcome, utilising the square root of the absolute walking distance to accommodate the skewed data. However, as this made the data difficult to interpret, a Tobit regression model using raw absolute walking distance data was used as well. Neuromuscular electrical stimulation improved the difference in absolute walking distance at 3 months but this was not statistically significant (square root of absolute walking distance: 0.835 units, 95% confidence interval −0.67 to 2.34 units; p = 0.28/absolute walking distance raw data: 27.18 m, 95% confidence interval −26.92 to 81.28 m; p = 0.323). Supervised exercise therapy participants showed a markedly improved absolute walking distance compared with patients receiving best medical therapy only at 3 months (square root of absolute walking distance: 3.295 units 95% confidence interval 1.77 to 4.82; p < 0.001/absolute walking distance raw data: 121.71 m, 95% confidence interval 67.32 to 176.10; p ≤ 0.001). Neuromuscular electrical stimulation significantly improved absolute walking distance at 3 months for mild claudicants (square root of absolute walking distance: 2.877 units, 95% confidence interval 0.51 to 5.25; p = 0.019/absolute walking distance raw data: 120.55 m, 95% confidence interval 16.03 to 225.06; p = 0.03) compared to the control arm. This was an unplanned (post hoc) analysis. There were no clear differences in mechanistic measurements between the two treatment groups over the follow-up period. Serious adverse events were evenly reported between the two groups; all being classified as either not related or unlikely to be related to the study device. Limitations: Absolute walking distance was used as the primary outcome measure; there was a large range of baseline distances in both groups with right-skewed distribution. We did not stratify by baseline absolute walking distance for the primary outcome analysis. Additionally, only 160 patients had analysable primary outcome data due to missing treadmill data. Conclusions: Supervised exercise therapy is an effective treatment for intermittent claudication. Neuromuscular electrical stimulation appears to be beneficial as an adjunct to supervised exercise therapy and on its own in mild claudicants. Future work: Further studies are needed to confirm the effectiveness of neuromuscular electrical stimulation in combination with supervised exercise therapy, and in mild to moderate claudicants in a larger sample size. Study registration: This trial is registered as ISRCTN18242823. Funding: This project was funded by the Efficacy and Mechanism Evaluation (EME) Programme, a Medical Research Council (MRC) and National Institute for Health and Care Research (NIHR) partnership (project number 15/180/68). This will be published in full in Efficacy and Mechanism Evaluation; Vol. 10, No. 2. See the NIHR Journals Library website for further project information. Infrastructure support for this research was provided by the NIHR Imperial Biomedical Research Centre (BRC) (with others, e.g. NIHR Imperial CRF, Imperial College ECMC, NIHR Imperial PSTRC, NIHR London MIC, etc.).

Background INES (INteractive model for Extrapolation of Survival and cost) provides an open-access tool powered by R that implements partitioned survival models (PSM). This article describes the properties of the tool, and the situations where INES may or may not be suitable. Methods INES is designed to be used by investigators or healthcare professionals who have a good grasp of the principles of economic evaluation and understand the strengths and weaknesses of partitioned survival models, but are not sufficiently familiar with a statistical package such as Excel or R to be able to construct and test a de-novo PSM themselves. INES is delivered to the user via a batch file. Once downloaded to the user’s hard drive, it interacts with the user via a portable version of R with web interactivity built in shiny. INES requires absolutely no knowledge of R and the user does not need to have R or any of its dependences installed. Hence the user will deal with a standalone shiny app. Inputs (digitalized survival curves, unit costs, posology, hazard ratios, discount rate) can be uploaded from a template spreadsheet. Results An example of the inputs and outputs of INES are given that may serve as a tutorial. Conclusion INES offers a rapid, flexible, robust open access tool for calculating a PSM that can be used in many different contexts.