Largest real-world Flow Diverter study verifies safety and efficacy for phenox’ p64 Flow Modulation Device

November 16, 2021

November 16, 2021, Bochum, Germany. The authors of the Diversion-p64  study 1 conclude that phenox’ p64 Flow Modulation Device has a high efficacy and demonstrates one of the lowest rates of morbidity-mortality compared to similar studies. The trial represents the largest prospective study on flow diversion to date. With 420 patients enrolled in 26 centres across 10 countries, the results provide strong evidence for maximized flow modulation effect from the 64-wire braid design of the p64 device for treating intracranial aneurysms.

The study, recently published in the Journal of Neurointerventional Surgery (JNIS), was a single-arm, international, multicentre, prospective, post-market clinical follow-up trial to assess the safety and effectiveness of the p64 device. A total of 445 devices were used to treat anterior circulation aneurysms between December 2015 and January 2019.

In the study, all of the primary and secondary endpoints were achieved. The primary efficacy endpoint was the complete occlusion of the aneurysm, based on the Raymond-Roy Occlusion Classification(RROC). The study results confirm a high complete occlusion rate of 83.7% (86% adequate occlusion) at 1-year associated with a low morbidity-mortality rate of 2.69%. An independent core lab, blinded to all clinical information, reconfirmed the aneurysm types and locations, matched the eligibility criteria and assessed aneurysms at both follow-up visits. In comparison to previous Flow Diverter studies2, the aneurysm occlusion rates seen in Diversion-p64 are favourable.

The study results prove that the implantation of p64 was highly reliable. In 98.1% of cases, the p64 was deployed at the desired location and 99.3% of the implanted devices detached without any difficulties. The p64 Flow Modulation Device, manufactured and distributed by phenox GmbH (Bochum, Germany), is designed to allow controlled and selective modulation of blood flow in intracranial arteries. The p64 device received the CE mark in 2012 and is constructed from 64 braided wires. The p64 is the only flow diverter available on the market that is mechanically detachable.

Building on the positive results of Diversion-p64, the just recently initiated COATING study represents the first comparative, randomized study to properly evaluate Flow Diverters with surface modification. COATING will include p64 MW HPC, the newest Flow Diverter developed by phenox, with Hydrophilic Polymer Coating technology. The reduced thrombogenicity of the implant surface by HPC is the next significant step towards improved patient safety.

  1. Bonafe A, Perez MA, Henkes H, et al. J NeuroIntervent Surg Epub ahead of print: 15 Nov 2021. doi:10.1136/ neurintsurg-2021-017809
  2. Hanel RA, Kallmes DF, Lopes DK, et al. Prospective study on embolization of intracranial aneurysms with the pipeline device: the PREMIER study 1 year results. J Neurointerv Surg 2020;12:62–6. doi:10.1136/neurintsurg-2019-015091
    Pierot L, Spelle L, Berge J, et al. SAFE study (Safety and efficacy Analysis of FRED Embolic device in aneurysm treatment): 1-year clinical and anatomical results. J Neurointerv Surg 2019;11:184–9. doi:10.1136/neurintsurg-2018-014261
    Taschner CA, Stracke CP, Dorn F, et al. Derivo embolization device in the treatment of unruptured intracranial aneurysms: a prospective multicenter study. J Neurointerv Surg 2021;13:541–6. doi:10.1136/neurintsurg-2020-016303
    Wakhloo AK, Lylyk P, de Vries J, et al. Surpass Flow Diverter in the Treatment of Intracranial Aneurysms: A Prospective Multicenter Study. Am J
    Neuroradiol 2015;36:98–107. doi:10.3174/ajnr.A4078

About phenox

Since its founding in 2005, phenox has been dedicated to developing innovative clinically proven breakthrough technologies and solutions for treating neurovascular diseases. Endovascular specialists use phenox products to treat ischemic and hemorrhagic strokes.

phenox offers an expanding portfolio of innovative treatment options, including primary interventional technologies used today. Its product range consists of the pRESET mechanical thrombectomy system, the p64, p64 MW and p48 MW Flow Diverters for treating complex intracranial aneurysms and dissections, and the pCONUS implant for treating complex, wide-neck bifurcation aneurysms. The proprietary HPC technology leads to increased patient safety by significantly reducing thrombogenicity of implant surfaces. In 2020, phenox became the exclusive distributor for the Avenir Coiling System in the US and Europe.

Phenox’s main office is located in Bochum, Germany with subsidiaries located in Galway, Ireland, the UK, Italy, and Irvine, California (USA). phenox is a private company, financed by private funds as well as the NRW BANK, Venture Fond GmbH & Co.KG, together with SHS Technologiefonds GmbH & Co.KG.

For more information about phenox and its products, visit  

Phenox and its products are registered trademarks of phenox GmbH, registered in Germany and other countries. All other trademarks and trade names used in in this press release are the property of their respective owners.

Contact information

phenox GmbH
Lise-Meitner-Allee 31 - 44801 Bochum, Germany
Tel.: +49 (0)234 36 919 0 -
Fax: +49 (0)234 36 919 19

CEO: Prof. Dr.-Ing. Hermann Monstadt, Ralf Hannes
Registry Court: AG Bochum, HRB 10388

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