The Stenting versus Aggressive Medical Therapy for Intracranial Arterial Stenosis Trial: Reanalysis Using the FDA "On Label" Criteria.

BACKGROUND AND PURPOSE: Due to higher rates of 1-month stroke and death with Wingspan intracranial stent placement observed in SAMMPRIS, the Food and Drug Administration (FDA) announced a more limited indication for Wingspan stent.

METHODS

We compared the results of intracranial stent placement with best medical treatment in patients recruited in SAMMPRIS who met the new "on label" criteria with those who were categorized as "off label." The primary endpoint was any stroke or death occurring within 30 days of enrollment, or an ischemic stroke in the territory of the symptomatic intracranial artery from day 31 after study entry to completion of follow-up.

RESULTS

A total of 31 (7%) among 451 recruited patients met the "on label" criteria. The relative risk of primary endpoint was lower in "on label" patients treated with stent placement compared with best medical treatment (relative risk .61, 95% confidence interval .2-1.7) but higher in "off label" patients (relative risk 1.81, 95% confidence interval 1.2-2.6). Primary endpoint was seen in 20% and 23.4% of patients treated with stent placement in "on label" and "off label" patients, respectively. Primary endpoint was seen in 25% and 14.2% of patients treated with best medical treatment in "on label" and "off label" patients, respectively.

CONCLUSION

The new FDA "on label" criteria may identify a small group of people, who may benefit from intracranial stent placement due to higher risk of primary endpoint in those treated with best medical treatment.