Cell Therapy and Functional Recovery of Stroke

Stroke is the most common cause of disability. Brain repair mechanisms are often insufficient to allow a full recovery. Stroke damage involve all brain cell type and extracellular matrix which represent the crucial "glio-neurovascular niche" useful for brain plasticity. Regenerative medicine including cell therapies hold great promise to decrease post-stroke disability of many patients, by promoting both neuroprotection and neural repair through direct effects on brain lesion and/or systemic effects such as immunomodulation. Mechanisms of action vary according to each grafted cell type: "peripheral" stem cells, such as mesenchymal stem cells (MSC), can provide paracrine trophic support, and neural stem/progenitor cells (NSC) or neurons can act as direct cells' replacements. Optimal time window, route, and doses are still debated, and may depend on the chosen medicinal product and its expected mechanism such as neuroprotection, delayed brain repair, systemic effects, or graft survival and integration in host network. MSC, mononuclear cells (MNC), umbilical cord stem cells and NSC are the most investigated. Innovative approaches are implemented concerning combinatorial approaches with growth factors and biomaterials such as injectable hydrogels which could protect a cell graft and/or deliver drugs into the post-stroke cavity at chronic stages. Through main publications of the last two decades, we provide in this review concepts and suggestions to improve future translational researches and larger clinical trials of cell therapy in stroke.

Challenges for Economic Evaluations of Advanced Therapy Medicinal Products: A Systematic Review

OBJECTIVES

Advanced therapy medicinal products (ATMPs) are drugs for human use for the treatment of chronic, degenerative, or life-threatening diseases that are based on genes, tissues, or cells. This article aimed to identify and critically review published economic analyses of ATMPs.

METHODS

A systematic review of economic analyses of ATMPs was undertaken. Study characteristics, design, sources of data, resources and unit costs, modeling and extrapolation methods, study results, and sensitivity analyses were assessed.

RESULTS

A total of 46 economic analyses of ATMP (from 45 articles) were included; 4 were cell therapy medicinal products, 33 gene therapy medicinal products, and 9 tissue-engineered products. 30 therapies had commercial marketing approval; 39 studies were cost-utility analysis, 5 were cost-effectiveness analysis, and 2 were cost only studies. Four studies predicted that the ATMP offered a step change in the management of the condition and 10 studies estimated that the ATMP would offer a lower mean cost.

CONCLUSIONS

Comparison with historical controls, pooling of data, and use of techniques such as mixture cure fraction models should be used cautiously. Sensitivity analyses should be used across a plausible range of prices. Clinical studies need to be designed to align with health technology assessment requirements, including generic quality of life, and payers should aim for clarity of criteria. Regulators and national payers should aim for compatibility of registers to allow interchange of data. Given the increasing reliance on industry-funded economic analyses, careful critical review is recommended.

A systematic review of economic evaluations of advanced therapy medicinal products

Aims

Advanced therapy medicinal products (ATMPs) represent a new category of medicinal products with a potential for transformative improvements in health outcomes but at exceptionally high prices. Routine adoption of ATMPs requires robust evidence of their cost‐effectiveness.

Methods

A systematic literature review of economic evaluations of ATMPs, including gene therapies, somatic cell therapies and tissue‐engineered products, was conducted. Literature was searched using MedLine, Embase, PubMed, Cochrane Register, the NHS Economic Evaluation Database and the grey literature of health technology assessment organisations with search terms relating to ATMPs and economic evaluations. Titles were screened independently by 2 reviewers. Articles deemed to meet the inclusion criteria were screened independently on abstract, and full texts reviewed. Study findings were appraised critically.

Results

4514 articles were identified, of which 23 met the inclusion criteria. There was some evidence supporting the cost‐effectiveness of: chimeric antigen receptor T‐cell therapy axicabtagene–ciloleucel (Yescarta), embryonic neural stem cells, tumour infiltrating lymphocytes, in vitro expanded myoblast, autologous chondrocyte implantation, ex vivo gene therapy (Strimvelis) and voretigene neparvovec (Luxturna). However, estimates of cost‐effectiveness were associated with significant uncertainty and high likelihood of bias, resulting from largely unknown long‐term outcomes, a paucity of evidence on health state utilities and extensive modelling assumptions.

Conclusion

There are critical limitations to the economic evidence for ATMPs, most notably in relation to evidence on the durability of treatment effect, and the reliability of opinion‐based assumptions necessary when evidence is absent.

Economic Evaluation of Stem Cell Therapies in Neurological Diseases: A Systematic Review

OBJECTIVES

To examine economic evaluation studies of stem cell therapies (SCTs) in neurological disorders and to provide an overview of the quality of the economic evidence available on this topic.

METHODS

The review examined studies that performed an economic evaluation of the use of stem cells in adult patients with neurological diseases and that were published in English during the period 2007 to 2017. Data analyzed and reported included study population, disease indication, main analytical approaches for the economic analysis and perspective, key assumptions made or tested in sensitivity analyses, cost outcomes, estimates of incremental cost effectiveness, and approaches to quantifying decision uncertainty.

RESULTS

A total of three studies reporting on the findings of the economic evaluation of the use of SCT in stroke, Parkinson disease, and secondary progressive multiple sclerosis, respectively, were identified. All three studies conducted a cost-utility analysis using decision-analytic models and reported an incremental cost per quality-adjusted life-years gained (incremental cost-effectiveness ratio) versus standard care. These studies reported meaningful cost savings in stroke, Parkinson disease, and secondary progressive multiple sclerosis in the base-case scenarios.

CONCLUSIONS

Despite significant progress in clinical research in the use of SCT in neurological diseases, economic evaluation of these therapies is still at a nascent stage. Given the early stage of research inputs (clinical and cost outcomes data) into the models per se, further research is urgently needed to enable meaningful assessment of the cost effectiveness of these advanced therapies and to ensure sustainable access for population groups most likely to benefit in clinical practice.

Cell Therapy in Stroke-Cautious Steps Towards a Clinical Treatment

In the future, stroke patients may receive stem cell therapy as this has the potential to restore lost functions. However, the development of clinically deliverable therapy has been slower and more challenging than expected. Despite recommendations by STAIR and STEPS consortiums, there remain flaws in experimental studies such as lack of animals with comorbidities, inconsistent approaches to experimental design, and concurrent rehabilitation that might lead to a bias towards positive results. Clinical studies have typically been small, lacking control groups as well as often without clear biological hypotheses to guide patient selection. Furthermore, they have used a wide range of cell types, doses, and delivery methods, and outcome measures. Although some ongoing and recent trial programs offer hints that these obstacles are now being tackled, the Horizon2020 funded RESSTORE trial will be given as an example of inconsistent regulatory requirements and challenges in harmonized cell production, logistic, and clinical criteria in an international multicenter study. The PISCES trials highlight the complex issues around intracerebral cell transplantation. Therefore, a better understanding of translational challenges is expected to pave the way to more successful help for stroke patients.

Long-term cost-effectiveness of thrombectomy for acute ischaemic stroke in real life: An analysis based on data from the Swedish Stroke Register (Riksstroke)

Background

Randomised controlled trials have demonstrated substantial clinical benefit for thrombectomy in patients with acute ischaemic stroke and proximal anterior circulation arterial occlusion.

Aim

We investigated the long-term cost-effectiveness of thrombectomy after thrombolysis versus thrombolysis alone using real-world outcome data on need for health care, home help and nursing home care.

Methods

We used real-life resource use and survival data from the Swedish Stroke Register and pooled outcomes from five randomised controlled trials published in 2015 in a newly constructed Markov cost-effectiveness model with a societal perspective. Data were stratified by age (18–64; 65–74; 75–84 years) and modified Rankin scale at three months for patients with an index ischaemic stroke in 2014 fulfilling inclusion criteria NIHSS ≥ 8 before treatment and treated with thrombolysis ( n = 710). Univariate sensitivity analyses explored robustness of results. A life-time perspective and 3% discount rate were applied.

Results

Thrombectomy increases the health care cost per patient (+GBP 9000) mainly because of intervention costs, but the reduced burden on the social services (home help services −GBP 13,000; nursing home care −GBP 26,000) implies overall cost savings. The average patient gain was 1.0 quality-adjusted life year (QALY) with higher gains for younger age groups. Thrombectomy was a dominant strategy in the base case and all sensitivity analyses where social services were considered.

Conclusion

Thrombectomy has a small effect on hospital costs except for the direct intervention cost. However, thrombectomy is highly likely to lead to substantial cost savings in the social service sector, up to four times the increase in health-care costs.

Differences in willingness to pay for an extraction, a filling, and cleaning teeth at various levels of oral health-related quality of life, as measured by oral impacts on daily performance, among older adults in Singapore

OBJECTIVE

To examine the differences in Willingness to pay (WTP) for an extraction, a filling, and cleaning of teeth among older adults with varying levels of Oral Health-related Quality of Life (OHQoL).

BACKGROUND

OHQoL has been used extensively to measure utilities as reported by individuals of interest. Currently there are no reports that examine the WTP of individuals at various levels of OHQoL.

METHODS

A convenience sample of adults 60 years or older were recruited. Besides other domains, questionnaires were used to assess WTP (extraction, filling, and cleaning of teeth), OHQoL (using Oral Impacts on Daily Performance-OIDP), McArthur scale, and access to care.

RESULTS

Tamil ethnicity was related to higher WTP for an extraction (mean ratio, 1.63-3.98; 95% Confidence Interval [CI]), increase of age in years was related to lower WTP for extraction (mean ratio, 0.96-1.00 [95%CI]) and increasing OIDP score was related to lower WTP for extractions (mean ratio, 0.80-0.99 [95%CI]). Tamil ethnicity was associated with higher WTP for fillings (mean ratio, 2.69-6.44 [95%CI]); higher age in years was associated with lower WTP for fillings (mean ratio, 0.94-0.99 [95%CI]), and higher OIDP scores was trending to be associated to lower WTP for filling (mean ratio, 0.80-1.00 [95%CI]). Tamil Ethnicity was also associated with higher WTP for cleaning (mean ratio, 2.14-7.19 [95%CI]), higher age in years was also associated with cleaning (mean ratio, 0.94-0.99 [95%CI]).

CONCLUSION

Individuals with higher OIDP scores tended to have lower WTP for extraction, filling and cleaning; with significant differences reported for extraction.