Dr Osama ZaidatOsama Zaidat, MD
Stryker announced that the FDA granted premarket approval to its Neuroform Atlas Stent System for treatment of wide-neck, intracranial aneurysms in conjunction with embolic detachable coils.

The approval was backed by data from the ATLAS Investigational Device Exemption (IDE) trial which proved the efficacy of the device. It’s indicated for use with neurovascular embolization coils in the anterior circulation of the neurovasculature for the endovascular treatment of patients 18 years of age and older with saccular wide-necked intracranial aneurysms arising from a parent vessel with a diameter of ≥2 mm and ≤4.5 mm that are not amenable to treatment with surgical clipping. Neuroform Atlas Stent System was previously approved under a Humanitarian Device Exemption, restricting its use to specific hospitals with approval.

The system is a self-expanding nitinol stent used in conjunction with metal coils to pack weakened blood vessel sacs within the brain. The stent’s positioned across the aneurysm neck to hold metal coils and occlude the aneurysm.

“Enhanced stent conformability, a low-profile delivery system and high deployment accuracy even in distal anatomy puts Neuroform Atlas in a category of its own,” co-principal investigator, Brain Jankowitz, director of the neuroendovascular fellowship program, University of Pittsburgh Medical Center, said in a statement.1 “This product is changing my clinical practice by allowing more patients with difficult aneurysms an option at endovascular treatment while improving the quality and safety of treatment.”

The prospective, multi-center, single arm ATLAS study enrolled 30 subjects at 8 institutions. All 30 participants completed clinical and imaging follow-up at 6 months and 27/30 completed in-person 12-month clinical follow-up within or outside the study 12-month time window. Participants were predominately female (80%) and white (83.3%). All participants successfully treated with the Neuroform Atlas stent-assisted coil embolization. Study participants were implanted with 33 stents for treatment of aneurysms; 27 (90%) patients has 1 sent and 3 (10%) patients had 2 stents placed in a y-configuration and ranged from 3 mm to 4.5 mm.

The primary efficacy endpoint was the rate of 12-month complete aneurysm angiographic occlusion without target aneurysm retreatment or significant parent artery stenosis at the target location. The primary safety endpoint was the rate of major ipsilateral stroke or neurological death within 12 months.

Secondary outcomes included technical success, incidence of post-procedural major ipsilateral stroke, incidence of site-reported device-related serious adverse effects, functional clinical outcome, all-cause mortality, rate of target aneurysm occlusion and recanalization, target aneurysm retreatment rate, stent migration at the 12-month angiogram, and parent artery patency 12-months post procedure.

The primary efficacy endpoint was observed in 26/30 participants (86.7%, 95% CI 69.3% to 96.2%), compared with 25/27 (92.6%, 95% CI 75.7% to 99.1%) participants who completed the 12-month angiographic follow-up. The primary safety endpoint of stroke occurred in 1 patient, who made a complete clinical recovery at discharge, and there were no neurological deaths.2

There were no unanticipated adverse effects reported from the clinical study. There were 3 events adjudicated by the Clinical Events Committee (CEC) as major (n=1) or minor stroke (n=2). The most frequently reported procedure-related adverse effects occurred in 12 subjects (40%) and were categorized as nervous system disorders (n=20). The non-serious adverse effects included 11 reports of headaches in 10 subjects (33.3%), one report of migraine with aura (3.3%), one report of ophthalmoplegic migraine (3.3%), and one report of mental confusion (3.3%). The second most commonly reported procedure-related adverse effect in nervous
system disorders were 6 cerebral vasoconstriction events which occurred in 5 subjects (16.7%), 3 subjects (10%) experienced 4 access site-related adverse effects. Additionally, 2 participants experienced eye disorders (6.7%), 1 (3.3%) experienced arterial restenosis, and 1 subject (3.3%) experienced 2 respiratory disorders). All of these adverse effects were reported as non-serious and all resolved with no residual effects.3

“Neuroform Atlas represents a significant advancement in the treatment of wide-neck aneurysms which is now backed by the largest IDE stent-coil trial completed to date,” co-principal investigator of the U.S. Neuroform Atlas investigational trial Osama Zaidat, MD, director of the neuroscience and stroke center, Mercy Hospital, said in a statement.1 “More impressive were the results with an 84.7% primary efficacy rate, a 4.4% primary safety rate, and a 3.8% retreatment rate.”
REFERENCE
1. Stryker receives FDA premarket approval for the Neuroform Atlas® Stent System to treat brain aneurysms [news release]. Kalamazoo, Mich.: Stryker; May 20, 2019. prnmedia.prnewswire.com/news-releases/stryker-receives-fda-premarket-approval-for-the-neuroform-atlas-stent-system-to-treat-brain-aneurysms-300852724.html. Accessed May 20, 2019.
2. Jankowitz J, Hanel R, Jadhav A, et al. Neuroform Atlas Stent System for the treatment of intracranial aneurysm: primary results of the Atlas Humanitarian Device Exemption cohort. Journal of NeuroInterventional Surgery. 2019. doi: 10.1136/neurintsurg-2018-014455.
3. Neuroform Atlas Stent System [prescribing information]. Fremont, Calif.: Stryker Neurovascular; 2017. www.accessdata.fda.gov/cdrh_docs/pdf2/H020002S046C.pdf. Accessed May 21, 2019.