The Source for Neurovascular News and Education

March 28, 2024

 

Key Points:

  • SWIFT-PRIME analysis compares cost-effectiveness of Solitaire + tPA vs tPA alone for acute ischemic stroke
  • Initial costs higher with Solitaire, but savings appear in about 2 years

 

In appropriate patients, treating acute ischemic stroke with the Solitaire stent retriever plus tPA is not only clinically beneficial but also more cost effective than using tPA alone. The findings, from a new analysis of SWIFT-PRIME trial data, were published online December 27, 2016, ahead of print in Stroke.

David J. Cohen, MD, of the University of Missouri-Kansas City School of Medicine (Kansas City, MO), and colleagues representing the SWIFT-PRIME investigators conducted a prospective economic substudy alongside the original trial. They measured in-trial costs for patients using detailed medical resource utilization and hospital billing data and assessed utility weights at 30 and 90 days using the EuroQol-5 dimension questionnaire.

Index hospitalization costs were greater for patients who received treatment with both Solitaire (Medtronic) and tPA, and the difference was primarily driven by the cost of the procedure itself (mean $14,640 per patient). In contrast, costs from discharge to 90 days were nearly $5,000 lower per patient for the stent retriever group. Overall costs accumulated in the hospital and after discharge through 90 days remained higher among patients who received a stent retriever, however (table 1).

Table 1. Costs of Treatment

 

Solitaire +

IV tPA

(n = 98)

IV tPA

(n = 92)

P Value

Index Hospitalization

$45,761

$28,578

.001

From Discharge to 90 Days

$11,270

$16,174

.014

Total Through 90 Days

$57,031

$44,752

.001


The investigators estimated costs and life-expectancy after SWIFT-PRIME for each surviving patient using a model based on trial data and inputs derived from a contemporary cohort of ischemic stroke survivors. Higher utility values for patients treated with the Solitaire device led to higher in-trial quality-adjusted life-years (QALYs). In multiple lifetime projection analyses, treatment with the Solitaire was associated with significant QALY gains as well as a cost savings of more than $20,000 per patient (table 2).

Table 2. Long-term Cost-Effectiveness

 

Solitaire +

IV tPA

(n = 98)

IV tPA

(n = 92)

P Value

QALYs Gained

6.79

5.05

.005

Projected Lifetime Cost

$215,781

$238,984

 


Updated Data Made the Difference

While the defining reason to use the Solitaire device remains its clinical efficacy, the clear conclusion of the analysis, Dr. Cohen told NVX in a telephone interview, is that “economics should not be a barrier to applying this technology.”

He expects that these findings will be influential for third-party payers because cost savings with Solitaire were seen as early as 2 years following the index hospitalization. That means that the same payer who covered the procedure will likely benefit from the long-term cost savings, which is not always the case when cost savings are only seen after 10 or more years.

“The fact that the results are consistent across all the different subgroups that we tested is important,” he added. “It emphasizes the fact that as long as you have a patient who is like the ones included in this trial, with a large vessel anterior circulation stroke presenting in a reasonably timely fashion, the economics don’t suggest that we should be targeting this therapy to any particular [sub]group.”

The results actually came as somewhat of a surprise, Dr. Cohen said.

“There aren’t many things in medicine that make patients do better—and in this case reduce disability and extend lives—and also save the healthcare system money,” he observed. “That’s a pretty rare finding, and it has to do with the fact that these stroke patients, when they have a high degree of disability, are very expensive to take care of long-term and they often live long enough to accrue a lot of costs.”

According to Dr. Cohen, this analysis yielded different results from previous cost-effectiveness studies not because of any inherent differences in the stent retrievers used or in the original trial designs, but because here researchers employed more up-to-date survival projections and cost data.

While these findings are limited to the Solitaire device in particular, Dr. Cohen speculated that a similar device with a similar cost that provides similarly positive outcomes should offer comparable cost savings when used in appropriate patients.

 


 

 

Source:

Shireman TI, Wang K, Saver JL et al. Cost-Effectiveness of Solitaire stent retriever thrombectomy for acute ischemic stroke: Results from the SWIFT-PRIME trial (Solitaire with the intention for thrombectomy as primary endovascular treatment for acute ischemic stroke). Stroke. 2016;Epub ahead of print.

 

Disclosures:

The SWIFT-PRIME trial was supported by Medtronic, Inc.

Dr. Cohen reports receiving consulting fees from Medtronic, Inc.