The cost utility of autologous chondrocytes implantation using ChondroCelect® in symptomatic knee cartilage lesions in Belgium

Efficacy and safety of mesenchymal stem cell-derived microvesicles in mouse inflammatory arthritis

OBJECTIVE

To determine the effective and safe intravenous doses of mesenchymal stem cells (MSCs)-derived microvesicles (MVs) and to elucidate the possible causes of death in mice receiving high-dose MVs.

METHODS

MVs were isolated from human MSCs by gradient centrifugation. Mice with collagen-induced arthritis were treated with different doses of intravenous MVs or MSCs. Arthritis severity, white blood cell count, and serum C-reactive protein levels were measured. To assess the safety profile of MSCs and MVs, mice were treated with different doses of MSCs and MVs, and LD50 was calculated. Mouse lungs and heart were assessed by live fluorescence imaging, histopathological measurements, and immunohistochemistry to explore the possible causes of death. Serum concentrations of cTnT, cTnI, and CK-MB were determined by ELISA. With the H9C2 cardiomyocyte cell line,  cellular uptake of MVs was observed using confocal microscopy and cell toxicity was assessed by CCK-8 and flow cytometry.

RESULTS

Intravenous treatment with MSCs and MVs alleviated inflammatory arthritis, while high doses of MSCs and MVs were lethal. Mice receiving a maximum dose of MSCs (0.1 mL of MSCs at 109/mL) died immediately, while mice receiving a maximum dose of MVs (0.1 mL of MVs at 1012/mL) exhibited tears, drooling, tachycardia, shortness of breath, unbalanced rollover, bouncing, circular crawling, mania, and death. Some mice died after exhibiting convulsions and other symptoms. All mice died shortly after injecting the maximum dose of MSCs. Histologically, mice receiving high doses of MSCs frequently developed pulmonary embolism, while those receiving high doses of MVs died of myocardial infarction. Consistently, the serum levels of cTnT, cTnI, and CK-MB were significantly increased in the MVs-treated group (P < 0.05). The LD50 of intravenous MVs was 1.60 × 1012/kg. Further, MVs could enter the cell. High doses of MVs induced cell apoptosis, though low concentrations of MVs induced cell proliferation.

CONCLUSIONS

Appropriate dosages of MVs and MSCs are effective treatments for inflammatory arthritis while MVs and MSCs overdose is unsafe by causing cardiopulmonary complications.

Individualized metal implants for focal cartilage lesions in the knee can be cost-effective: A simulation on 47-year-old in a Swedish setting

OBJECTIVES

In the aging population, the knee is the joint most commonly causing impaired function and incapacity. While definite treatment by prosthetic replacement is often performed late, symptomatic knee cartilage lesions cause much suffering also in younger ages. Early intervention could, therefore, be instituted at an early stage to the benefit of both patients and society. Small, metal surface, resurfacing implants have been tested with promising results. A system that features patient-specific implants and surgical instruments shows good clinical results and favorable survival rates. This study aims to assess the cost utility of this metal device compared with microfracture (MFX), being the standard procedure in Sweden.

METHODS

We constructed a simulation model in Excel. In the model, a cohort of 47-year-old patients (which is the mean age of patients treated with the metal implant) with symptomatic knee cartilage lesions received either MFX or metal implantation. Outcomes for the cohort were simulated over 40 years, such as in a previously published model based on MFX, and sensitivity analyses (deterministic and probabilistic) of the results were undertaken. Data on transition probabilities, costs, and quality of life were taken from clinical data, published literature, and official price lists. Only direct medical costs were included.

RESULTS

Results from the analysis showed that the metal device is a cost-effective treatment strategy compared with MFX. The incremental cost-effectiveness ratio (ICER) reached acceptable levels at ∼5 years postoperatively. Over the full-time horizon of 40 years, the metal device was cost saving with concomitant gains in quality-adjusted life years (QALYs), translating to a dominant treatment strategy. Results were robust according to sensitivity analysis with the initial success rate of up to three years for both metal and MFX having the largest impact.

CONCLUSIONS

A metal implant may be a cost-effective treatment alternative for patients in their 40's when compared to MFX in a Swedish setting.

LEVEL OF EVIDENCE

5 [1].

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.

Cost Effectiveness of Allogeneic Umbilical Cord Blood-Derived Mesenchymal Stem Cells in Patients with Knee Osteoarthritis

OBJECTIVES

The aim of this study was to assess the cost effectiveness of allogeneic umbilical cord blood-derived mesenchymal stem cells with sodium hyaluronate (hUCB-MSC) compared with microfracture in patients with knee cartilage defects caused by osteoarthritis (OA) in South Korea.

METHODS

A partitioned survival model approach was taken consisting of five mutually exclusive health states: excellent, good, fair, poor, and death over a 20-year time horizon. Utility values were obtained from a randomized clinical trial. Cost data were extracted from a database provided by the Health Insurance Review & Assessment Service, and the utilization of healthcare services was estimated from an expert panel of orthopedic surgeons using a structured questionnaire. The incremental cost-effectiveness ratio (ICER) in terms of quality-adjusted life-years (QALY) was calculated. Deterministic and probabilistic sensitivity analyses were performed.

RESULTS

In the base case, the incremental costs of US$14,410 for hUCB-MSC therapy along with its associated QALY gain of 0.857 resulted in an ICER of US$16,812 (₩18,790,773) per QALY (95% confidence interval [CI] US$13,408-US$20,828) when compared with microfracture treatment from a healthcare payer perspective. From a societal perspective, the ICER was US$268 (₩299,255) per QALY (95% CI -US$2915 to US$3784). When using a willingness-to-pay threshold of US$22,367/QALY, the probability of hUCB being cost effectiveness compared with microfracture was 99% from the healthcare payer perspective and 100% from the societal perspective.

CONCLUSIONS

The study demonstrated that hUCB-MSC therapy was cost effective compared with microfracture when treating patients with knee OA. These findings should inform health policy decision makers about considerations for cost-effective therapy for treating knee OA to ultimately enhance population health.

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.

Health Economic Evaluations of Hip and Knee Interventions in Orthopaedic Sports Medicine: A Systematic Review and Quality Assessment

BACKGROUND

The economic burden of musculoskeletal diseases is substantial and growing. Economic evaluations compare costs and health benefits of interventions simultaneously to help inform value-based care; thus, it is crucial to ensure that studies are using appropriate methodology to provide valid evidence on the cost-effectiveness of interventions. This is particularly the case in orthopaedic sports medicine, where several interventions of varying costs are available to treat common hip and knee conditions.

PURPOSE

To summarize and evaluate the quality of economic evaluations in orthopaedic sports medicine for knee and hip interventions and identify areas for quality improvement.

STUDY DESIGN

Systematic review; Level of evidence, 3.

METHODS

The Medline, AMED, OVID Health Star, and EMBASE databases were searched from inception to March 1, 2020, to identify economic evaluations that compared ≥2 interventions for hip and/or knee conditions in orthopaedic sports medicine. We assessed the quality of full economic evaluations using the Quality of Health Economic Studies (QHES) tool, which consists of 16 questions for a total score of 100. We classified studies into quartiles based on QHES score (extremely poor quality to high quality) and we evaluated the frequency of studies that addressed each of the 16 QHES questions.

RESULTS

A total of 93 studies were included in the systematic review. There were 41 (44%) cost analyses, of which 21 (51%) inappropriately concluded interventions were cost-effective. Only 52 (56%) of the included studies were full economic evaluations, although 40 of these (77%) fell in the high-quality quartile. The mean QHES score was 83.2 ± 19. Authors consistently addressed 12 of the QHES questions; questions that were missed or unclear were related to statistical uncertainty, appropriateness of costing methodology, and discussion of potential biases. The most frequently missed question was whether the cost perspective of the analysis was stated and justified.

CONCLUSION

The number of studies in orthopaedic sports medicine is small, despite their overall good quality. Yet, there are still many highly cited studies based on low-quality or partial economic evaluations that are being used to influence clinical decision-making. Investigators should follow international health economic guidelines for study design and critical appraisal of studies to further improve quality.

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.

Treatment Costs of Matrix-Associated Autologous Chondrocyte Implantation Compared With Microfracture: Results of a Matched-Pair Claims Data Analysis on the Treatment of Cartilage Knee Defects in Germany

BACKGROUND

Articular cartilage damage is caused by traumatic sport accidents or age-related degeneration and might lead to osteoarthritis, which represents a socioeconomic burden to society. Cartilage damage in the knee is commonly treated surgically with microfracture (MFX) or matrix-associated autologous chondrocyte implantation (MACI).

PURPOSE

To quantify the initial and follow-up costs associated with MFX and MACI treatments from the viewpoint of statutory health insurance in Germany.

STUDY DESIGN

Economic decision analysis; Level of evidence, 2.

METHODS

This comparative study was based on an anonymized representative claims data set of 4 million patients covered by statutory health insurance in Germany. Patients undergoing outpatient or inpatient treatment with MACI or MFX for cartilage damage in the knee between January 1, 2012, and December 31, 2013, were included and evaluated over 5 years. Groups (MACI and MFX) were adjusted via propensity score matching before initial treatment. The matched groups were compared regarding their outpatient, inpatient, pharmaceutical, and other costs during the 5-year period.

RESULTS

In total, 127 patients per group were analyzed (59.1% male, 40.9% female; mean age, 37 years). In the year of the initial surgical procedure, costs were €14,804.13 in the MACI group and €5458.59 in the MFX group. In years 2 and 3 after initial surgery, treatment costs were comparable between patients treated with MACI (€2897.97 and €2114.87, respectively) and MFX (€2842.66 and €1967.42, respectively), with slightly higher treatment costs for those treated with MACI. In years 4 and 5 after surgery, costs were less in patients treated with MACI (€2154.79 and €1478.08, respectively) than in those treated with MFX (€2232.57 and €2061.63, respectively). Costs related to revision surgery were, on average, €3732 for MACI and €3765 for MFX. Thus, additional costs in years with revision surgery were €1672 for MACI and €1915 for MFX.

CONCLUSION

This was the first study to analyze a large representative population claims database with propensity score matching, and results indicated that follow-up costs of patients treated with MACI and MFX began to converge over time. We found that total costs for MACI were higher than for MFX but that additional costs for MACI were lower than previously reported. Perceived morbidity may have little to do with cost.

Autologous Chondrocyte Implantation with Chondrosphere for Treating Articular Cartilage Defects in the Knee: An Evidence Review Group Perspective of a NICE Single Technology Appraisal

Chondrosphere (Spherox) is a form of autologous chondrocyte implantation (ACI). It is licensed for repair of symptomatic articular cartilage defects of the femoral condyle and the patella of the knee with defect sizes up to 10 cm² in adults. In a single technology appraisal (STA) [TA508] undertaken by the National Institute of Health and Care Excellence (NICE), Warwick Evidence was the Evidence Review Group (ERG) invited to independently review the evidence submitted by the manufacturer, Co.Don. The clinical effectiveness data came from their COWISI randomised controlled trial (RCT), which compared Chondrosphere with microfracture (MF). The timing of this appraisal was unfortunate given that MF was no longer the most relevant comparator because NICE had contemporaneously published guidance approving ACI in place of MF. Moreover, the COWISI RCT enrolled mostly patients with small defect sizes. Evidence of clinical effectiveness for Chondrosphere used in people with larger defect size came from another RCT, which compared three doses of Chondrosphere and that by design could not provide evidence comparing Chondrosphere to any other forms of ACI. To estimate the relative clinical performance of Chondrosphere versus other ACI, Co.Don conducted an indirect treatment comparison by network meta-analyses (NMA). The NMA was flawed in that the distribution of population characteristics that are effect modifiers greatly differed across the treatment comparisons of the network. The ERG questioned both the appropriateness of the NMA and the validity of the resulting estimates. Co.Don estimated the cost-effectiveness of Chondrosphere using a lifetime Markov model with all patients receiving the first repair during the first cycle of the model then moving into one of three health states: success, no further repair (NFR), or a second repair, if necessary. Subsequent to the first cycle, those who were a success either remained a success or moved to second repair. All those in NFR remained in NFR. The cost-effectiveness of Chondrosphere compared to other ACI forms relied on the clinical effectiveness estimates of success and failure rates obtained from the company's indirect comparisons, the validity of which the ERG questioned. The company revised cost-effectiveness estimates for Chondrosphere versus MF and for Chondrosphere versus matrix-applied characterised autologous cultured chondrocyte implant (MACI) were £4360 and around £18,000 per quality-adjusted life year gained, respectively. NICE recommended ACI using Chondrosphere for treating symptomatic articular cartilage defects of the femoral condyle and patella of the knee in adults only if certain requirements were met.

A brief introduction to health economics

To convince policy-makers or funders of health care of the value of orthopaedic interventions, we need to consider value for money (cost-effectiveness), as well as clinical effectiveness. This article provides an introduction to health economics to set the scene for papers on the use of allografts in the knee.

The cost-effectiveness of osteochondral allograft transplantation in the knee

PURPOSE

Osteochondral allografts (OCA) consist of a layer of hyaline cartilage and a layer of underlying bone. They are used to repair combined defects of articular cartilage and bone. Such defects often occur in people far too young to have knee arthroplasty, for whom the main alternative to OCA is conservative symptomatic care, which will not prevent development of osteoarthritis. The aim of this report was to assess the cost-effectiveness of osteochondral allograft transplantation in the knee.

METHODS

Systematic review of evidence on clinical effectiveness and economic modelling.

RESULTS

The evidence on osteochondral allograft transplantation comes from observational studies, but often based on good quality prospective registries of all patients having such surgery. Without controlled trials, it was necessary to use historical cohorts to assess the effect of osteochondral grafts. There is good evidence that OCA are clinically effective with a high graft survival rate over 20 years. If an OCA graft fails, there is some evidence that revision with a second OCA is also effective, though less so than primary OCA. Economic modelling showed that osteochondral allograft transplantation was highly cost-effective, with costs per quality adjusted life year much lower than many other treatments considered cost effective.

CONCLUSIONS

Osteochondral allograft transplantation appears highly cost-effective though the cost per quality adjusted life year varies according to the widely varying costs of allografts. Based on one small study, revision OCA also appears very cost-effective, but more evidence is needed.

LEVEL OF EVIDENCE

II.

Cost-effectiveness of treatments for non-osteoarthritic knee pain conditions: A systematic review

INTRODUCTION

Knee pain is common in adolescents and adults and is associated with an increased risk of developing knee osteoarthritis. The aim of this systematic review was to gather and appraise the cost-effectiveness of treatment approaches for non-osteoarthritic knee pain conditions.

METHOD

A systematic review was conducted according to the PRISMA guidelines and registered on PROSPERO (CRD42016050683). The literature search was done in MEDLINE via PubMed, EMBASE, The Cochrane Library, and the National Health Service Economic Evaluation Database. Study selection was carried out by two independent reviewers and data were extracted using a customized extraction form. Study quality was assessed using the Consensus on Health Economic Criteria list.

RESULTS

Fifteen studies were included. The majority regarded the treatment of anterior cruciate ligament (ACL) injuries, but we also identified studies evaluating other knee pain conditions such as meniscus injuries, cartilage defects, and patellofemoral pain syndrome. Study interventions were categorized as surgical or non-surgical interventions. The surgical interventions included ACL reconstruction, chondrocyte implantation, meniscus scaffold procedure, meniscal allograft transplantation, partial meniscectomy, microfracture, and different types of autografts and allografts. The non-surgical management consisted of physical therapy, rehabilitation, exercise, counselling, bracing, and advice. In general, for ACL injuries surgical management alone or in combination with rehabilitation appeared to be cost-effective. The quality of the economic evaluations was of moderate to high quality.

CONCLUSION

There was insufficient evidence to give a firm overview of cost-effective interventions for non-osteoarthritic knee pain, but surgical treatment of acute ACL injury appeared cost-effective. There is very little data regarding the cost-effectiveness of non-surgical interventions for non-traumatic knee conditions.

Autologous chondrocyte implantation in the knee: systematic review and economic evaluation

BACKGROUND

The surfaces of the bones in the knee are covered with articular cartilage, a rubber-like substance that is very smooth, allowing frictionless movement in the joint and acting as a shock absorber. The cells that form the cartilage are called chondrocytes. Natural cartilage is called hyaline cartilage. Articular cartilage has very little capacity for self-repair, so damage may be permanent. Various methods have been used to try to repair cartilage. Autologous chondrocyte implantation (ACI) involves laboratory culture of cartilage-producing cells from the knee and then implanting them into the chondral defect.

OBJECTIVE

To assess the clinical effectiveness and cost-effectiveness of ACI in chondral defects in the knee, compared with microfracture (MF).

DATA SOURCES

A broad search was done in MEDLINE, EMBASE, The Cochrane Library, NHS Economic Evaluation Database and Web of Science, for studies published since the last Health Technology Assessment review.

REVIEW METHODS

Systematic review of recent reviews, trials, long-term observational studies and economic evaluations of the use of ACI and MF for repairing symptomatic articular cartilage defects of the knee. A new economic model was constructed. Submissions from two manufacturers and the ACTIVE (Autologous Chondrocyte Transplantation/Implantation Versus Existing Treatment) trial group were reviewed. Survival analysis was based on long-term observational studies.

RESULTS

Four randomised controlled trials (RCTs) published since the last appraisal provided evidence on the efficacy of ACI. The SUMMIT (Superiority of Matrix-induced autologous chondrocyte implant versus Microfracture for Treatment of symptomatic articular cartilage defects) trial compared matrix-applied chondrocyte implantation (MACI^®) against MF. The TIG/ACT/01/2000 (TIG/ACT) trial compared ACI with characterised chondrocytes against MF. The ACTIVE trial compared several forms of ACI against standard treatments, mainly MF. In the SUMMIT trial, improvements in knee injury and osteoarthritis outcome scores (KOOSs), and the proportion of responders, were greater in the MACI group than in the MF group. In the TIG/ACT trial there was improvement in the KOOS at 60 months, but no difference between ACI and MF overall. Patients with onset of symptoms < 3 years' duration did better with ACI. Results from ACTIVE have not yet been published. Survival analysis suggests that long-term results are better with ACI than with MF. Economic modelling suggested that ACI was cost-effective compared with MF across a range of scenarios.

LIMITATIONS

The main limitation is the lack of RCT data beyond 5 years of follow-up. A second is that the techniques of ACI are evolving, so long-term data come from trials using forms of ACI that are now superseded. In the modelling, we therefore assumed that durability of cartilage repair as seen in studies of older forms of ACI could be applied in modelling of newer forms. A third is that the high list prices of chondrocytes are reduced by confidential discounting. The main research needs are for longer-term follow-up and for trials of the next generation of ACI.

CONCLUSIONS

The evidence base for ACI has improved since the last appraisal by the National Institute for Health and Care Excellence. In most analyses, the incremental cost-effectiveness ratios for ACI compared with MF appear to be within a range usually considered acceptable. Research is needed into long-term results of new forms of ACI.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42014013083.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Cost Effectiveness of Characterised Chondrocyte Implantation for Treatment of Cartilage Defects of the Knee in the UK

INTRODUCTION

Until recently, treatment options for damage to cartilage in the knee were limited to the use of microfracture or, occasionally, mosaicplasty. The developments of autologous and characterised chondrocyte implantation have provided new treatment options but have large upfront costs. The objective of this study was to estimate the cost effectiveness of characterised chondrocyte implantation in the UK National Health Service.

METHODS

An economic model was constructed in Microsoft Excel^®, with patients undergoing either microfracture or chondrocyte implantation. Following treatment failure, patients can undergo a series of interventions, ultimately ending in knee replacement. Effectiveness and utility were modelled using clinical trial data, which were supplemented with synthesised registry data, and costs were taken from published sources. Results were expressed in clinical events, quality-adjusted life-years (QALYs) and British pounds. Both costs and outcomes were discounted at 3.5 % per year.

RESULTS

Chondrocyte implantation is estimated to reduce the lifetime probability of knee replacement by 50 % in comparison with microfracture, and to increase QALYs by 0.72 (16.57 vs. 15.85). Costs were estimated to be £23,307 for chondrocyte implantation, and £8008 for microfracture, with the incremental cost of £15,299 for chondrocyte implantation reflecting reduced resource use offsetting some of the procedure cost. These values gave a cost per QALY gained of £21,245.

CONCLUSION

Chondrocyte implantation is estimated to provide substantial patient benefits over a lifetime horizon, with a considerable increase in QALYs. Despite the increase in costs, the procedure is cost effective at standard thresholds used in the UK.

Fabrication of High-Aspect-Ratio 3D Hydrogel Microstructures Using Optically Induced Electrokinetics

We present a rapid hydrogel polymerization and prototyping microfabrication technique using an optically induced electrokinetics (OEK) chip, which is based on a non-UV hydrogel curing principle. Using this technique, micro-scale high-aspect-ratio three-dimensional polymer features with different geometric sizes can be fabricated within 1–10 min by projecting pre-defined visible light image patterns onto the OEK chip. This method eliminates the need for traditional photolithography masks used for patterning and fabricating polymer microstructures and simplifies the fabrication processes. This technique uses cross-link hydrogels, such as poly(ethylene glycol) (PEG)-diacrylate (PEGDA), as fabrication materials. We demonstrated that hydrogel micropillar arrays rapidly fabricated using this technique can be used as molds to create micron-scale cavities in PDMS (polydimethylsiloxane) substrates. Furthermore, hollow, circular tubes with controllable wall thicknesses and high-aspect ratios can also be fabricated. These results show the potential of this technique to become a rapid prototyping technology for producing microfluidic devices. In addition, we show that rapid prototyping of three-dimensional suspended polymer structures is possible without any sacrificial etching process.

Third-generation autologous chondrocyte implantation versus mosaicplasty for knee cartilage injury: 2-year randomized trial

Numerous surgical techniques have been developed to treat osteochondral defects of the knee. A study reported encouraging outcomes of third-generation autologous chondrocyte implantation achieved using the solid agarose-alginate scaffold Cartipatch®. Whether this scaffold is better than conventional techniques remains unclear. This multicenter randomized controlled trial compared 2-year functional outcomes (IKDC score) after Cartipatch® versus mosaicplasty in patients with isolated symptomatic femoral chondral defects (ICRS III and IV) measuring 2.5-7.5 cm(2) . In addition, a histological evaluation based on the O'Driscoll score was performed after 2 years. We needed 76 patients to demonstrate an at least 10-point subjective IKDC score difference with α = 5% and 90% power. During the enrolment period, we were able to include 55 patients, 30 of them were allocated at random to Cartipatch® and 25 to mosaicplasty. After 2 years, eight patients had been lost to follow-up, six in the Cartipatch® group, and two in the mosaicplasty group. The baseline characteristics of the two groups were not significantly different. The mean IKDC score and score improvement after 2 years were respectively 73.7 ± 20.1 and 31.8 ± 20.8 with Cartipatch® and 81.5 ± 16.4 and 44.4 ± 15.2 with mosaicplasty. The 12.6-point absolute difference in favor of mosaicplasty is statistically significant. Twelve adverse events were recorded in the Cartipatch® group against six in the mosaicplasty group. After 2 years, functional outcomes were significantly worse after Cartipatch® treatment compared to mosaicplasty for isolated focal osteochondral defects of the femur.

Landscape of current and emerging cell therapy clinical trials in the UK: current status, comparison to global trends and future perspectives

Cell Therapy Clinical Trial and Preclinical Research databases have been established by the Cell Therapy Catapult to document current and future cell therapy clinical trials in the UK. We identified 41 ongoing trials in April 2014, an increase of seven trials from April 2013. In addition, we identified 45 late-stage preclinical research projects. The majority of the clinical trials are early phase, primarily led by academic groups. The leading therapeutic areas are cancer, cardiology and neurology. The trends in the UK are also seen globally. As the field matures, more later phase and commercial studies will emerge and the challenges will likely evolve into how to manufacture sufficient cell quantities, manage complex logistics for multi-center trials and control cost.

Cost-Effectiveness of Bariatric Surgery Prior to Total Knee Arthroplasty in the Morbidly Obese: A Computer Model-Based Evaluation

BACKGROUND

Obesity is associated with adverse outcomes and increased costs after total knee arthroplasty. Bariatric surgery is an effective treatment for morbid obesity, but its cost-effectiveness for weight loss prior to total knee arthroplasty is unknown. The purpose of this study was to evaluate the cost-effectiveness of bariatric surgery prior to total knee arthroplasty for patients in whom medical treatment of obesity and knee osteoarthritis had failed.

METHODS

A state-transition Markov model was constructed to compare the cost-utility of two treatment protocols for patients with morbid obesity and end-stage knee osteoarthritis: (1) immediate total knee arthroplasty and (2) bariatric surgery two years prior to the total knee arthroplasty. The probability of transition for each health state and its utility were derived from the literature. Costs, expressed in 2012 United States dollars, were estimated with use of administrative and claims data. Costs and utilities were discounted at 3% annually, and effectiveness was expressed in quality-adjusted life-years (QALYs). The principal outcome measure was the incremental cost-effectiveness ratio (ICER). One-way, two-way, and probabilistic sensitivity analyses were performed, using $100,000 per QALY as the threshold willingness to pay.

RESULTS

Morbidly obese patients undergoing total knee arthroplasty alone had lower QALYs gained than patients who underwent bariatric surgery two years prior to the total knee arthroplasty. The ICER between these two procedures was approximately $13,910 per QALY, well below the threshold willingness to pay. Results were stable across broad value ranges for independent variables. Probabilistic sensitivity analysis found that the median ICER was $14,023 per QALY (95% confidence interval, $4875 to $51,210 per QALY).

CONCLUSIONS

This model supports bariatric surgery prior to total knee arthroplasty as a cost-effective option for improving outcomes in morbidly obese patients with end-stage knee osteoarthritis who are indicated for total knee arthroplasty.

LEVEL OF EVIDENCE

Economic and Decision Analysis Level II. See Instructions for Authors for a complete description of levels of evidence.

Osteochondral regeneration with a novel aragonite-hyaluronate biphasic scaffold: up to 12-month follow-up study in a goat model

BACKGROUND

The regeneration of articular hyaline cartilage remains an elusive goal despite years of research. Recently, an aragonite-hyaluronate (Ar-HA) biphasic scaffold has been described capable of cartilage regeneration over a 6-month follow-up period. This study was conducted in order to assess the fate of the regenerated osteochondral tissue in a 12-month-long validated caprine model.

HYPOTHESIS/PURPOSE

The hypothesis was that the implantation of the Ar-HA implant leads to tissue regeneration and maturation.

STUDY DESIGN

A two-arm caprine model of a critical osteochondral defect compares the fate of acute osteochondral defects (group A) to Ar-HA implanted defects (group B).

METHODS

Critical 6 mm in diameter and 10-mm in depth osteochondral defects were created in the load-bearing medial femoral condyle of 20 mature goats and randomized into two groups. In group A (n = 6), a blood clot spontaneously filled the defect; in group B (n = 14), a single Ar-HA implant reconstructed the defect. The animals were sacrificed after either 6 or 12 months. Parameters assessed included clinical evaluation, x-rays, micro-CT, ultrasound and histology at both time points, and specimen high-field magnetic resonance imaging with T2 mapping at the 12-month time point.

RESULTS

In most group A animals, the defects were not reconstructed (1/3 at 6 months, and 0/3 at 12 months). Defects in group B were mostly reconstructed (5/7 at 6 months and 6/7 at 12 months). Group A defects were either empty or contained fibrous repair tissue; while group B filling was compatible with hyaline cartilage and normal bone.

CONCLUSION

Ar-HA scaffolds implanted in critical osteochondral defects result in hyaline cartilage formation and subchondral bone regeneration. The results improved at the 12-month time point compared to the 6-month time point, indicating a continuous maturation process without deterioration of the repair tissue.

CLINICAL RELEVANCE

Osteochondral defects are common in humans; the results of the current study suggest that an acellular Ar-HA scaffold might induce cartilage and subchondral bone regeneration.

The cost-effectiveness of surgical treatment of medial unicompartmental knee osteoarthritis in younger patients: a computer model-based evaluation

BACKGROUND

Surgical options for the management of medial compartment osteoarthritis of the varus knee include high tibial osteotomy, unicompartmental knee arthroplasty, and total knee arthroplasty. We sought to determine the cost-effectiveness of high tibial osteotomy and unicompartmental knee arthroplasty as alternatives to total knee arthroplasty for patients fifty to sixty years of age.

METHODS

We built a probabilistic state-transition computer model with health states defined by pain, postoperative complications, and subsequent surgical procedures. We estimated transition probabilities from published literature. Costs were determined from Medicare reimbursement schedules. Health outcomes were measured in quality-adjusted life-years (QALYs). We conducted analyses over patients' lifetimes from the societal perspective, with health and cost outcomes discounted by 3% annually. We used probabilistic sensitivity analyses to account for uncertainty in data inputs.

RESULTS

The estimated discounted QALYs were 14.62, 14.63, and 14.64 for high tibial osteotomy, unicompartmental knee arthroplasty, and total knee arthroplasty, respectively. Discounted total direct medical costs were $20,436 for high tibial osteotomy, $24,637 for unicompartmental knee arthroplasty, and $24,761 for total knee arthroplasty (in 2012 U.S. dollars). The incremental cost-effectiveness ratio (ICER) was $231,900 per QALY for total knee arthroplasty and $420,100 per QALY for unicompartmental knee arthroplasty. Probabilistic sensitivity analyses showed that, at a willingness-to-pay (WTP) threshold of $50,000 per QALY, high tibial osteotomy was cost-effective 57% of the time; total knee arthroplasty, 24%; and unicompartmental knee arthroplasty, 19%. At a WTP threshold of $100,000 per QALY, high tibial osteotomy was cost-effective 43% of time; total knee arthroplasty, 31%; and unicompartmental knee arthroplasty, 26%.

CONCLUSIONS

In fifty to sixty-year-old patients with medial unicompartmental knee osteoarthritis, high tibial osteotomy is an attractive option compared with unicompartmental knee arthroplasty and total knee arthroplasty. This finding supports greater utilization of high tibial osteotomy for these patients. The cost-effectiveness of high tibial osteotomy and of unicompartmental knee arthroplasty depend on rates of conversion to total knee arthroplasty and the clinical outcomes of the conversions.

Arthroscopic airbrush assisted cell implantation for cartilage repair in the knee: a controlled laboratory and human cadaveric study

OBJECTIVE

The objective of this study was to investigate the feasibility of arthroscopic airbrush assisted cartilage repair.

METHODS

An airbrush device (Baxter) was used to spray both human expanded osteoarthritic chondrocytes and choncrocytes with their pericellular matrix (chondrons) at 1 × 10(6) cells/ml fibrin glue (Tissucol, Baxter) in vitro. Depth-dependent cell viability was assessed for both methods with confocal microscopy. Constructs were cultured for 21 days to assess matrix production. A controlled human cadaveric study (n = 8) was performed to test the feasibility of the procedure in which defects were filled with either arthroscopic airbrushing or needle extrusion. All knees were subjected to 60 min of continuous passive motion and scored on outline attachment and defect filling.

RESULTS

Spraying both chondrocytes and chondrons in fibrin glue resulted in a homogenous cell distribution throughout the scaffold. No difference in viability or matrix production between application methods was found nor between chondrons and chondrocytes. The cadaveric study revealed that airbrushing was highly feasible, and that defect filling through needle extrusion was more difficult to perform based on fibrin glue adhesion and gravity-induced seepage. Defect outline and coverage scores were consistently higher for extrusion, albeit not statistically significant.

CONCLUSION

Both chondrons and chondrocytes can be evenly distributed in a sprayed fibrin glue scaffold without affecting viability while supporting matrix production. The airbrush technology is feasible, easier to perform than needle extrusion and allows for reproducible arthroscopic filling of cartilage defects.

Quantitative assessment of barriers to the clinical development and adoption of cellular therapies: A pilot study

There has been a large increase in basic science activity in cell therapy and a growing portfolio of cell therapy trials. However, the number of industry products available for widespread clinical use does not match this magnitude of activity. We hypothesize that the paucity of engagement with the clinical community is a key contributor to the lack of commercially successful cell therapy products. To investigate this, we launched a pilot study to survey clinicians from five specialities and to determine what they believe to be the most significant barriers to cellular therapy clinical development and adoption. Our study shows that the main concerns among this group are cost-effectiveness, efficacy, reimbursement, and regulation. Addressing these concerns can best be achieved by ensuring that future clinical trials are conducted to adequately answer the questions of both regulators and the broader clinical community.

The implementation of novel collaborative structures for the identification and resolution of barriers to pluripotent stem cell translation

Increased global connectivity has catalyzed technological development in almost all industries, in part through the facilitation of novel collaborative structures. Notably, open innovation and crowd-sourcing-of expertise and/or funding-has tremendous potential to increase the efficiency with which biomedical ecosystems interact to deliver safe, efficacious and affordable therapies to patients. Consequently, such practices offer tremendous potential in advancing development of cellular therapies. In this vein, the CASMI Translational Stem Cell Consortium (CTSCC) was formed to unite global thought-leaders, producing academically rigorous and commercially practicable solutions to a range of challenges in pluripotent stem cell translation. Critically, the CTSCC research agenda is defined through continuous consultation with its international funding and research partners. Herein, initial findings for all research focus areas are presented to inform global product development strategies, and to stimulate continued industry interaction around biomanufacturing, strategic partnerships, standards, regulation and intellectual property and clinical adoption.

Economic evaluation of BST-CarGel as an adjunct to microfracture vs microfracture alone in knee cartilage surgery

OBJECTIVES

Knee cartilage damage is a common cause of referral for orthopedic surgery. Treatment aims to reduce pain and symptoms by repairing cartilage. Microfracture, the current standard of care, yields good short-term clinical outcomes; however, treatment might fail after 2-3 years. A Chitosan-Beta glycerolphosphate-based medical device (BST-CarGel) is used as an adjunct to microfracture and demonstrates improvements in quantity and quality of repaired tissue, potentially reducing the risk of treatment failure. This study aimed to establish the economic value of BST-CarGel vs microfracture alone in knee cartilage repair from the societal perspective, using Germany as the reference market.

METHODS

A decision tree with a 20-year time-horizon was constructed, in which undesirable clinical events were inferred following initial surgery. These events consisted of pain management, surgery, and total knee replacement. Clinical outcomes were taken from the pivotal clinical trial, supplemented by other literature. Data and assumptions were validated by a Delphi panel. All relevant resource use and costs for procedures and events were considered.

RESULTS

In a group of patients with all lesion sizes, the model inferred that BST-CarGel yields a positive return on investment at year 4 (with 20-year cumulative cost savings of €6448). Reducing the incremental risk of treatment failure gap between the device and microfracture by 25-50% does not alter this conclusion. Cost savings are greatest for patients with large lesions; results for patients with small lesions are more modest.

LIMITATIONS

Clinical evidence for microfracture and other interventions varies in quality. Comparative long-term data are lacking. The comparison is limited to microfracture and looks only at costs without considering quality-of-life.

CONCLUSION

BST-CarGel potentially represents a cost-saving alternative for patients with knee cartilage injury by reducing the risk of clinical events through regeneration of chondral tissue with hyaline characteristics. Since the burden of this condition is high, both to the patient and society, an effective and economically viable alternative is of importance.

Early evaluation and value-based pricing of regenerative medicine technologies

Since the first pioneering scientists explored the potential of using human cells for therapeutic purposes the branch of regenerative medicine has evolved to become a mature industry. The focus has switched from ‘what can be done‘ to ‘what can be commercialized‘. Timely health economic evaluation supports successful marketing by establishing the value of a product from a healthcare system perspective. This article reports results from a research project on early health economic evaluation in collaboration with developers, clinicians and manufacturers. We present an approach to determine an early value-based price for a new treatment of cartilage defects of the knee from the area of regenerative medicine. Examples of using evaluation results for the purpose of business planning, market entry, preparing the coverage decision and managed entry are discussed.

Influence of sex on the outcome of autologous chondrocyte implantation in chondral defects of the knee

BACKGROUND

Sex-specific outcomes have been reported in anterior cruciate ligament reconstruction as well as in osteoarthrosis progression, but there are currently no related published data on autologous chondrocyte implantation (ACI). The present prospective study was performed to investigate sex-dependent differences in the results after ACI.

HYPOTHESIS

The clinical and magnetic resonance imaging (MRI) results after ACI of the knee are influenced by the patient's sex.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

The midterm clinical and MRI results of a cell-based fibrin-polymer graft for the treatment of full-thickness cartilage defects were evaluated preoperatively and 6, 12, and 48 months after surgery in 52 patients (male:female ratio, 25:27; average age, 35.6 years). Depending on the sex and the location of the defects (femoral condyles, n = 32; patellofemoral compartment, n = 20), patients were assigned to 4 different groups. Baseline clinical scores were compared with follow-up data by paired Wilcoxon tests for the Lysholm score and the International Knee Documentation Committee (IKDC) scoring system. Sex-specific differences were evaluated with the Mann-Whitney U test. The MRI evaluation was performed with the Henderson score at final follow-up.

RESULTS

Clinical scores improved in all groups over the whole study period (P < .05). Compared with female patients, male patients achieved significantly better results in the Lysholm score at all time intervals and in the IKDC score at 6 and 12 months after surgery (P < .05). In a subgroup analysis, female patients with patellar defects had the worst results in both clinical scores. With the available number of patients, MRI evaluation at 48 months after surgery revealed no significant difference in defect fill between male and female patients (P > .05). The Pearson correlation coefficient between both clinical scores and the MRI parameters of defect fill and cartilage signal was significant (P < .05).

CONCLUSION

Autologous chondrocyte implantation is a promising treatment option for full-thickness cartilage defects of male and female knee joints. Female patients with patellar defects have worse prognostic factors.

Advances in the Surgical Management of Articular Cartilage Defects: Autologous Chondrocyte Implantation Techniques in the Pipeline

OBJECTIVE

The purpose of this review is to gain insight into the latest methods of articular cartilage implantation (ACI) and to detail where they are in the Food and Drug Administration approval and regulatory process.

DESIGN

A PubMed search was performed using the phrase "Autologous Chondrocyte Implantation" alone and with the words second generation and third generation. Additionally, clinicaltrials.gov was searched for the names of the seven specific procedures and the parent company websites were referenced.

RESULTS

Two-Stage Techniques: BioCart II uses a FGF2v1 culture and a fibrinogen, thrombin matrix, whereas Hyalograft-C uses a Hyaff 11 matrix. MACI uses a collagen I/III matrix. Cartipatch consists of an agarose-alginate hydrogel. Neocart uses a high-pressure bioreactor for culturing with a type I collagen matrix. ChondroCelect makes use of a gene expression analysis to predict chondrocyte proliferation and has demonstrated significant clinical improvement, but failed to show superiority to microfracture in a phase III trial. One Step Technique: CAIS is an ACI procedure where harvested cartilage is minced and implanted into a matrix for defect filling.

CONCLUSION

As full thickness defects in articular cartilage continue to pose a challenge to treat, new methods of repair are being researched. Later generation ACI has been developed to address the prevalence of fibrocartilage with microfracture and the complications associated with the periosteal flap of first generation ACI such as periosteal hypertrophy. The procedures and products reviewed here represent advances in tissue engineering, scaffolds and autologous chondrocyte culturing that may hold promise in our quest to alter the natural history of symptomatic chondral disease.

Cartilage regeneration using zonal chondrocyte subpopulations: a promising approach or an overcomplicated strategy?

Cartilage defects heal imperfectly and osteoarthritic changes develop frequently as a result. Although the existence of specific behaviours of chondrocytes derived from various depth-related zones in vitro has been known for over 20 years, only a relatively small body of in vitro studies has been performed with zonal chondrocytes and current clinical treatment strategies do not reflect these native depth-dependent (zonal) differences. This is surprising since mimicking the zonal organization of articular cartilage in neo-tissue by the use of zonal chondrocyte subpopulations could enhance the functionality of the graft. Although some research groups including our own have made considerable progress in tailoring culture conditions using specific growth factors and biomechanical loading protocols, we conclude that an optimal regime has not yet been determined. Other unmet challenges include the lack of specific zonal cell sorting protocols and limited amounts of cells harvested per zone. As a result, the engineering of functional tissue has not yet been realized and no long-term in vivo studies using zonal chondrocytes have been described. This paper critically reviews the research performed to date and outlines our view of the potential future significance of zonal chondrocyte populations in regenerative approaches for the treatment of cartilage defects. Secondly, we briefly discuss the capabilities of additive manufacturing technologies that can not only create patient-specific grafts directly from medical imaging data sets but could also more accurately reproduce the complex 3D zonal extracellular matrix architecture using techniques such as hydrogel-based cell printing.

Regenerative medicine in rheumatic disease-progress in tissue engineering

Joint destruction occurs in both osteoarthritis and rheumatoid arthritis. Even in the era of biologic agents, this destruction can be delayed but not averted. As cartilage has limited ability to self-regenerate, joint arthroplasty is required. Here, we outline current tissue engineering procedures (including autologous chondrocyte implantation and in situ mesenchymal stem cell recruitment) that are routinely applied for the regenerative treatment of injured or early osteoarthritic cartilage. Potential future regenerative therapies, including administration of multipotent or pluripotent stem cells, are also discussed. In the future, cell-free, material-based (for cartilage lesions) or cell-free, factor-based (for osteoarthritic cartilage) therapies to facilitate the recruitment of repair cells and improve cartilage metabolism are likely to become more important. Moreover, delivery of anti-inflammatory factors or immunomodulatory cells could be a regenerative treatment option for rheumatoid arthritis. Tissue engineering faces a crucial phase to translate products into clinical routine and the regulatory framework for cell-based products in particular is an important issue.

Short-term outcome of the second generation characterized chondrocyte implantation for the treatment of cartilage lesions in the knee

PURPOSE

To evaluate short-term clinical and MRI outcome of the second generation characterized chondrocyte implantation (CCI) for the treatment of cartilage defects in the knee.

METHODS

Thirty-two patients aged 15-51 years with single International Cartilage Repair Society (ICRS) grade III/IV symptomatic cartilage defects of different locations in the knee were treated with CCI using a synthetic collagen I/III membrane to cover the defect. Clinical outcome was measured over 36 months by the Knee injury and Osteoarthritis Outcome Score (KOOS) and Visual Analogue Scale (VAS) for pain. Serial magnetic resonance imaging (MRI) scans of 22 patients were scored using the original and modified Magnetic resonance Observation of Cartilage Repair Tissue (MOCART) system.

RESULTS

The patients included in this study showed a significant gradual clinical improvement after CCI. The MRI findings of this pilot study were considered to be promising. No signs of deterioration were observed. A complete or hypertrophic filling was observed in 76.5% of the cases at 24 months of follow-up. No preventive effect of an avital membrane on the occurrence of hypertrophic repair tissue was observed on MRI. Three failures were observed among the 32 patients until now (9.4%).

CONCLUSIONS

This investigation provided useful information on the efficacy of this treatment. The short-term clinical and MRI outcome are promising. Large-scale and long-term trials are mandatory to confirm the results and the reliability of this procedure.

LEVEL OF EVIDENCE

IV.

Stem cell therapy for articular cartilage defects

BACKGROUND

Stem cells are easily accessible and have great potential for healing articular cartilage defects. These features make stem cell therapy an appealing approach for treating severely impaired joint function.

SOURCES OF DATA

Clinical and basic research articles and literature reviews.

AREAS OF AGREEMENT

Stem cells possess the potential to build articular cartilage. Malalignment and instability corrections and proper rehabilitation are crucial prerequisites for surgical procedures involving stem cell therapy. Smoking reduces the result.

AREAS OF CONTROVERSY

Ethical concerns remain unresolved. No standards are established for inducing stem cell potential, optimizing culturing media or harvesting. The risk of failure has not been determined.

GROWING POINTS

Surgical scaffolds can improve results. Care givers should focus on re-educating patients. Improved funding is needed for developing the therapy.

AREAS TIMELY FOR DEVELOPING RESEARCH

Define guidelines for stem cell therapy and demonstrate effectiveness.