Design of the economic evaluation for the Interventional Management of Stroke (III) trial

Emerging Roles of Exosomes in Stroke Therapy

Stroke is the number one cause of morbidity in the United States and number two cause of death worldwide. There is a critical unmet medical need for more effective treatments of ischemic stroke, and this need is increasing with the shift in demographics to an older population. Recently, several studies have reported the therapeutic potential of stem cell-derived exosomes as new candidates for cell-free treatment in stoke. This review focuses on the use of stem cell-derived exosomes as a potential treatment tool for stroke patients. Therapy using exosomes can have a clear clinical advantage over stem cell transplantation in terms of safety, cost, and convenience, as well as reducing bench-to-bed latency due to fewer regulatory milestones. In this review article, we focus on (1) the therapeutic potential of exosomes in stroke treatment, (2) the optimization process of upstream and downstream production, and (3) preclinical application in a stroke animal model. Finally, we discuss the limitations and challenges faced by exosome therapy in future clinical applications.

Cost-effectiveness evaluation of the PROPPR trial transfusion protocols

BACKGROUND

There have been no prior investigations of the cost effectiveness of transfusion strategies for trauma resuscitation. The Pragmatic, Randomized, Optimal Platelet and Plasma Ratios (PROPPR) study was a Phase III multisite, randomized trial in 680 subjects comparing the efficacy of 1:1:1 transfusion ratios of plasma and platelets to red blood cells with the 1:1:2 ratio. We hypothesized that 1:1:1 transfusion results in an acceptable incremental cost-effectiveness ratio, when estimated using patients' age-specific life expectancy and cost of care during the 30-day PROPPR trial period.

STUDY DESIGN AND METHODS

International Classification of Diseases, Ninth Revision codes were prospectively collected, and subjects were matched 1:2 to subjects in the Healthcare Utilization Program State Inpatient Data to estimate cost weights. We used a decision tree analysis, combined with standard costs and estimated years of expected survival to determine the cost effectiveness of the two treatments.

RESULTS

The 1:1:1 group had higher overall costs for the blood products but were more likely to achieve hemostasis and decreased hemorrhagic death by 24 hours (p = 0.006). For every 100 patients treated in the 1:1:1 group, eight more achieved hemostasis than in the 1:1:2 group. At 30 days, the total hospital cost per 100 patients was $5.6 million in the 1:1:1 group compared with $5.0 million in the 1:1:2 group. For each 100 patients, the 1:1:1 group had 218.5 more years of life expectancy. This was at a cost of $2994 per year gained.

CONCLUSION

The 1:1:1 transfusion ratio in severely injured hemorrhaging trauma patients is a very cost-effective strategy for increasing hemostasis and decreasing trauma deaths.

Identifying Unmet Rehabilitation Needs in Patients After Stroke With a Graphic Rehab-CompassTM

BACKGROUND

Unmet rehabilitation needs are common among stroke survivors. We aimed to evaluate whether a comprehensive graphic "Rehab-Compass," a novel combination of structured patient-reported outcome measures, was feasible and useful in facilitating a capture of patients' rehabilitation needs in clinical practice.

METHODS

A new graphic overview of broad unmet rehabilitation needs covers deficits in functioning, daily activity, participation, and quality of life. It was constructed by using 5 patient-oriented, well-validated, and reliable existing instruments with converted data into a 0 (worst outcome) to 100 (best outcome) scale but unchanged in terms of variable properties. Satisfaction of the Rehab-Compass^TM was studied by a qualitative interview of 9 patients with stroke and 3 clinicians. Practical feasibility and capacity of the instrument were evaluated in a cross-sectionalstudy with 48 patients at 5-month follow-ups after subarachnoid hemorrhage.

RESULTS

The Rehab-Compass^TM identified and graphically visualized a panoramic view of the multidimensional needs over time which was completed before clinical consultation. The Rehab-Compass^TM appeared to be feasible and time-efficientin clinical use. The interviews of both patients and clinicians showed high satisfaction when using the Rehab-Compass^TM graph. In the studied stroke patients, the Rehab-Compass^TM identified memory and processing information, fatigue, mood, and pain after subarachnoid hemorrhage as the most common problems.

CONCLUSIONS

The graphic Rehab-Compass^TM seems to be a feasible, useful, and time-saving tool for identification of unmet rehabilitation needs among stroke survivors in clinical practice. Further research is needed to make the Rehab-Compass^TM more concise and evaluate the instrument among different stroke subgroups.

Observed Cost and Variations in Short Term Cost-Effectiveness of Therapy for Ischemic Stroke in Interventional Management of Stroke (IMS) III

BACKGROUND

Examination of linked data on patient outcomes and cost of care may help identify areas where stroke care can be improved. We report on the association between variations in stroke severity, patient outcomes, cost, and treatment patterns observed over the acute hospital stay and through the 12-month follow-up for subjects receiving endovascular therapy compared to intravenous tissue plasminogen activator alone in the IMS (Interventional Management of Stroke) III Trial.

METHODS AND RESULTS

Prospective data collected for a prespecified economic analysis of the trial were used. Data included hospital billing records for the initial stroke admission and subsequent detailed resource use after the acute hospitalization collected at 3, 6, 9, and 12 months. Cost of follow-up care varied 6-fold for patients in the lowest (0-1) and highest (20+) National Institutes of Health Stroke Scale category at 5 days, and by modified Rankin Scale at 3 months. The kind of resources used postdischarge also varied between treatment groups. Incremental short-term cost-effectiveness ratios varied greatly when treatments were compared for patient subgroups. Patient subgroups predefined by stroke severity had incremental cost-effectiveness ratios of $97 303/quality-adjusted life year (severe stroke) and $3 187 805/quality-adjusted life year (moderately severe stroke).

CONCLUSIONS

Detailed economic and resource utilization data from IMS III provide powerful evidence for the large effect that patient outcome has on the economic value of medical and endovascular reperfusion therapies. These data can be used to inform process improvements for stroke care and to estimate the cost-effectiveness of endovascular therapy in the US health system for stroke intervention trials.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Registration number: NCT00359424.

Twelve-Month Clinical and Quality-of-Life Outcomes in the Interventional Management of Stroke III Trial

BACKGROUND AND PURPOSE

Randomized trials have indicated a benefit for endovascular therapy in appropriately selected stroke patients at 3 months, but data regarding outcomes at 12 months are currently lacking.

METHODS

We compared functional and quality-of-life outcomes at 12 months overall and by stroke severity in stroke patients treated with intravenous tissue-type plasminogen activator followed by endovascular treatment as compared with intravenous tissue-type plasminogen activator alone in the Interventional Management of Stroke III Trial. The key outcome measures were a modified Rankin Scale score ≤2 (functional independence) and the Euro-QoL EQ-5D, a health-related quality-of-life measure.

RESULTS

656 subjects with moderate-to-severe stroke (National Institutes of Health Stroke Scale ≥8) were enrolled at 58 centers in the United States (41 sites), Canada (7), Australia (4), and Europe (6). There was an interaction between treatment group and stroke severity in the repeated measures analysis of modified Rankin Scale ≤2 outcome (P=0.039). In the 204 participants with severe stroke (National Institutes of Health Stroke Scale ≥20), a greater proportion of the endovascular group had a modified Rankin Scale ≤2 (32.5%) at 12 months as compared with the intravenous tissue-type plasminogen activator group (18.6%, P=0.037); no difference was seen for the 452 participants with moderately severe strokes (55.6% versus 57.7%). In participants with severe stroke, the endovascular group had 35.2 (95% confidence interval: 2.1, 73.3) more quality-adjusted-days over 12 months as compared with intravenous tissue-type plasminogen activator alone.

CONCLUSIONS

Endovascular therapy improves functional outcome and health-related quality-of-life at 12 months after severe ischemic stroke.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00359424.

Drivers of costs associated with reperfusion therapy in acute stroke: the Interventional Management of Stroke III Trial

BACKGROUND AND PURPOSE

The Interventional Management of Stroke (IMS) III study tested the effect of intravenous tissue-type plasminogen activator (tPA) alone when compared with intravenous tPA followed by endovascular therapy and collected cost data to assess the economic implications of the 2 therapies. This report describes the factors affecting the costs of the initial hospitalization for acute stroke subjects from the United States.

METHODS

Prospective cost analysis of the US subjects was treated with intravenous tPA alone or with intravenous tPA followed by endovascular therapy in the IMS III trial. Results were compared with expected Medicare payments.

RESULTS

The adjusted cost of a stroke admission in the study was $35 130 for subjects treated with endovascular therapy after intravenous tPA treatment and $25 630 for subjects treated with intravenous tPA alone (P<0.0001). Significant factors related to costs included treatment group, baseline National Institutes of Health Stroke Scale, time from stroke onset to intravenous tPA, age, stroke location, and comorbid diabetes mellitus. The mean cost for subjects who had routine use of general anesthesia as part of endovascular therapy was $46 444 when compared with $30 350 for those who did not have general anesthesia. The costs of embolectomy for IMS III subjects and patients from the National Inpatient Sample cohort exceeded the Medicare diagnosis-related group payment in ≥75% of patients.

CONCLUSIONS

Minimizing the time to start of intravenous tPA and decreasing the use of routine general anesthesia may improve the cost-effectiveness of medical and endovascular therapy for acute stroke.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00359424.

Evidence for high translational potential of mesenchymal stromal cell therapy to improve recovery from ischemic stroke

Although ischemic stroke is a major cause of morbidity and mortality, current therapies benefit only a small proportion of patients. Transplantation of mesenchymal stromal cells (MSC, also known as mesenchymal stem cells or multipotent stromal cells) has attracted attention as a regenerative therapy for numerous diseases, including stroke. Mesenchymal stromal cells may aid in reducing the long-term impact of stroke via multiple mechanisms that include induction of angiogenesis, promotion of neurogenesis, prevention of apoptosis, and immunomodulation. In this review, we discuss the clinical rationale of MSC for stroke therapy in the context of their emerging utility in other diseases, and their recent clinical approval for treatment of graft-versus-host disease. An analysis of preclinical studies examining the effects of MSC therapy after ischemic stroke indicates near-universal agreement that MSC have significant favorable effect on stroke recovery, across a range of doses and treatment time windows. These results are interpreted in the context of completed and ongoing human clinical trials, which provide support for MSC as a safe and potentially efficacious therapy for stroke recovery in humans. Finally, we consider principles of brain repair and manufacturing considerations that will be useful for effective translation of MSC from the bench to the bedside for stroke recovery.

[Treatment of arterial and venous brain ischemia. Experts' recommendations: stroke management in the intensive care unit]

With thrombolysis, intravenous alteplase (0.9 mg/kg body weight, maximum 90 mg), with 10% of the dose given as a bolus followed by a 60-minute infusion, is recommended within 4.5 hours of onset of ischemic stroke. When indicated, intravenous thrombolysis must be initiated as soon as possible. It is possible to use intravenous alteplase in patients with seizures at stroke onset, if the neurological deficit is related to acute cerebral ischemia. Intravenous alteplase can be discussed for use on a case-by-case basis, according to risk of bleeding, in selected patients under 18 years and over 80 years of age, although for the current European recommendations this would be an off-label use. In hospitals with a stroke unit, intravenous thrombolysis is prescribed by a neurologist (current French labelling) or a physician having the French certification for neurovascular diseases (outside the current French labelling). The patient must be monitored in the stroke unit or in case of multiple organ failure in an intensive and critical care unit. In hospitals without a stroke unit, thrombolysis must be decided by the neurologist from the corresponding stroke unit via telemedicine. It is recommended to perform brain imaging 24 hours after thromboysis. Intra-arterial thrombolysis can be contemplated on a case-by-case basis after multidisciplinary discussion within a 6-hour time window for patients with acute middle cerebral artery or carotid occlusions, and within a larger time window for patients with basilar artery occlusion, because of their very poor spontaneous prognosis. Mechanical thrombectomy can also be contemplated in the same situations. With antiplatelet agents, it is recommended that patients receive aspirin (160 mg-325 mg) within 48 hours of ischemic stroke onset. When thrombolysis is performed or contemplated, it is recommended to delay the initiation of aspirin or other antithrombotic drugs for 24 hours. The use of antiplatelet agents that inhibit the glycoprotein IIb/IIIa receptor is not recommended. Urgent anticoagulation using heparin, low-molecular-weight heparins or danaparoid with the goal to treat ischemic stroke patients is not recommended. Secondary prevention by anticoagulation can be used, immediately or within the first days, after minor ischemic stroke or TIA in patients with a high risk for cardioembolism, if uncontrolled hypertension is absent. In patients with large infarcts and a high risk for cardioembolism, the timing for initiating anticoagulation must be decided on a case-by-case basis. In patients with anticoagulation who had an ischemic stroke, the decision to temporarily stop or maintain anticoagulation must be made on a case-by-case basis, depending on thromboembolic risk, level of anticoagulation at stroke onset and estimated risk of hemorrhagic transformation. It is not recommended to use neuroprotective agents in ischemic stroke patients. Patients with cerebral venous thrombosis must be treated with therapeutic doses of heparin, even in case of concomitant intracranial hemorrhage related to cerebral venous thrombosis. If the patient's status worsens despite adequate anticoagulation, thrombolysis may be used in selected cases. The optimal administration route (local or intravenous), thrombolytic agent (urokinase or alteplase) and dose are unknown. There is currently no recommendation with regard to local thrombolytic therapy in patients with dural sinus thrombosis. Urgent blood transfusions are recommended to reduce hemoglobin S to <30% in patients with sickle cell disease and acute ischemic stroke.

A cost-utility analysis of mechanical thrombectomy as an adjunct to intravenous tissue-type plasminogen activator for acute large-vessel ischemic stroke

BACKGROUND AND PURPOSE

Mechanical thrombectomy has the potential to improve recanalization rates and outcomes for patients with ischemic stroke, but potential gains could be offset by procedural complications and costs. We evaluated the cost and utility of combined intravenous (IV) tissue-type plasminogen activator (tPA) and mechanical thrombectomy compared to IV tPA alone for acute large-vessel ischemic stroke.

METHODS

We constructed a decision tree for a hypothetical 68-year-old with a large-vessel ischemic stroke who is eligible for IV tPA. The interventional strategy was IV tPA, a cerebral angiogram, and mechanical thrombectomy and thrombolysis if indicated. Recanalization, hemorrhage complications, and outcomes for the interventional strategy were from the Multi-MERCI study. The medical strategy was IV tPA using inputs from a comprehensive systematic review. Costs were estimated from Medicare reimbursements. We modeled lifetime costs and utilities for disability using a Markov model and Monte-Carlo multivariable sensitivity analysis.

RESULTS

For the baseline scenario, the recanalization rate was 72.9% for the interventional strategy and 46.2% for the medical strategy. For the interventional strategy, the symptomatic hemorrhage rate was 8.6% with recanalization and 15.4% without. For the medical strategy, the corresponding rates were 3.6% and 13.3%, respectively. The interventional strategy was cost-effective in 97.6% of simulations (incremental cost-effectiveness ratio $16 001/quality-adjusted life year; 95% CI, $2736-$39,232).

CONCLUSIONS

Based on observational data, the combination of IV tPA and mechanical thrombectomy for large-vessel ischemic stroke appears to be cost-effective compared to IV tPA alone. These findings require additional validation with randomized trial data.