Trevo Pro Vue Retriever and Trevo XP Pro Vue Retriever (Trevo Retriever)

K173352 · Concentric Medical, Inc. · POL · Feb 15, 2018 · Neurology

Device Facts

• Record ID: K173352
• Device Name: Trevo Pro Vue Retriever and Trevo XP Pro Vue Retriever (Trevo Retriever)
• Applicant: Concentric Medical, Inc.
• Product Code: POL · Neurology
• Decision Date: Feb 15, 2018
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 882.5600
• Device Class: Class 2
• Attributes: Therapeutic, Expedited Review

Intended Use

The Trevo Retriever is indicated for use to restore blood flow in the neurovasculature by removing thrombus for the treatment of acute ischemic stroke to reduce disability in patients with a persistent, proximal anterior circulation, large vessel occlusion, and smaller core infarcts who have first received intravenous tissue plasminogen activator (IV t-PA). Endovascular therapy with the device should start within 6 hours of symptom onset. The Trevo Retriever is intended to restore blood flow in the neurovasculature by removing thrombus in patients experiencing ischemic stroke within 8 hours of symptom onset. Patients who are ineligible for intravenous tissue plasminogen activator (IV t-PA) or who fail IV t-PA therapy are candidates for treatment. The Trevo Retriever is indicated for use to restore blood flow in the neurovasculature by removing thrombus for the treatment of acute ischemic stroke to reduce disability in patient, proximal anterior circulation, large vessel occlusion of the internal carotid artery (ICA) or middle cerebral artery (MCA)-M1 segments with smaller core infarcts (0-50 cc for age < 80 years, 0-20 cc for age ≥ 80 years). Endovascular therapy with the device should start within 6-24 hours of time last seen well in patients who are ineligible for intravenous tissue plasminogen activator (IV t-PA) or who fail IV t-PA therapy.

Device Story

Neurovascular mechanical thrombectomy device; flexible tapered nitinol core wire with shaped distal section; platinum markers for fluoroscopic visualization; hydrophilic coating. Delivered via microcatheter to thrombus site; microcatheter retracted to deploy shaped section; device and thrombus pulled back as system. Used in clinical/hospital settings by physicians. Output: restored blood flow in neurovasculature. Benefits: reduced disability, improved functional independence in acute ischemic stroke patients. Accessories: torque device for manipulation/locking to microcatheter; insertion tool for loading.

Clinical Evidence

DAWN study: multi-center, Bayesian adaptive-enrichment, prospective, randomized, open, masked endpoint trial (N=206). Primary endpoints: 90-day utility-weighted mRS and dichotomized mRS (0-2 vs 3-6). Treatment arm (n=107) showed superior functional independence (48.6% vs 13.1%, p<0.0001) and mean UW-mRS (5.5 vs 3.4) compared to medical management (n=99). Safety endpoints (mortality, sICH) showed no significant difference between arms.

Technological Characteristics

Core wire: Nitinol; Shaped section: Nitinol; Distal coil: Platinum/Tungsten; Proximal coil: 304 Stainless Steel; Solder: Gold/Tin; Coating: Sodium hyaluronate hydrophilic mixture. Mechanical thrombectomy principle. Dimensions per label. Radiopaque markers for fluoroscopy. Standalone device.

Indications for Use

Indicated for patients with acute ischemic stroke, persistent proximal anterior circulation large vessel occlusion (ICA or MCA-M1), and smaller core infarcts (0-50cc if <80 yrs; 0-20cc if ≥80 yrs). Candidates include those ineligible for or failing IV t-PA therapy. Treatment window: 6-24 hours from time last seen well.

Regulatory Classification

Identification

A neurovascular mechanical thrombectomy device for acute ischemic stroke treatment is a prescription device used in the treatment of acute ischemic stroke to improve clinical outcomes. The device is delivered into the neurovasculature with an endovascular approach, mechanically removes thrombus from the body, and restores blood flow in the neurovasculature.

Special Controls

In combination with the general controls of the FD&C Act, the Neurovascular Mechanical Thrombectomy Device for Acute Ischemic Stroke Treatment is subject to the following special controls:

*Classification.* Class II (special controls). The special controls for this device are:(1) The patient contacting components of the device must be demonstrated to be biocompatible. (2) Non-clinical performance testing must demonstrate that the device performs as intended under anticipated conditions of use, including: (i) Mechanical testing to demonstrate the device can withstand anticipated tensile, torsional, and compressive forces. (ii) Mechanical testing to evaluate the radial forces exerted by the device. (iii) Non-clinical testing to verify the dimensions of the device. (iv) Non-clinical testing must demonstrate the device can be delivered to the target location in the neurovasculature and retrieve simulated thrombus under simulated use conditions. (v) Non-clinical testing must demonstrate the device is radiopaque and can be visualized. (vi) Non-clinical testing must evaluate the coating integrity and particulates under simulated use conditions. (vii) Animal testing must evaluate the safety of the device, including damage to the vessels or tissue under anticipated use conditions. (3) Performance data must support the sterility and pyrogenicity of the patient contacting components of the device. (4) Performance data must support the shelf-life of the device by demonstrating continued sterility, package integrity, and device functionality over the specified shelf-life. (5) Clinical performance testing of the device must demonstrate the device performs as intended for use in the treatment of acute ischemic stroke and must capture any adverse events associated with the device and procedure. (6) The labeling must include: (i) Information on the specific patient population for which the device is intended for use in the treatment of acute ischemic stroke, including but not limited to, specifying time from symptom onset, vessels or location of the neurovasculature that can be accessed for treatment, and limitations on core infarct size. (ii) Detailed instructions on proper device preparation and use for thrombus retrieval from the neurovasculature. (iii) A summary of the clinical testing results, including a detailed summary of the device- and procedure-related complications and adverse events. (iv) A shelf life.

Predicate Devices

• Trevo ProVue Retriever and Trevo XP ProVue Retriever (DEN150049)

Reference Devices

• Trevo Retriever (K120961)

Submission Summary (Full Text)

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February 15, 2018

Concentric Medical, Inc. Rhoda M. Santos Senior Principal Regulatory Affairs Specialist 301 East Evelyn Avenue Mountain View, California 94041

#### Re: K173352

Trade/Device Name: Trevo ProVue Retriever and Trevo XP ProVue Retriever (Trevo Retriever) Regulation Number: 21 CFR 882.5600 Regulation Name: Neurovascular Mechanical Thrombectomy Device for Acute Ischemic Stroke Treatment Regulatory Class: Class II Product Code: POL, NRY Dated: January 12, 2018 Received: January 16, 2018

Dear Ms. Rhoda M. Santos:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820);

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and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/) and CDRH Learn (http://www.fda.gov/Training/CDRHLearn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (http://www.fda.gov/DICE) for more information or contact DICE by email ([e-mail]) or phone [phone] or 301-796-7100).

Sincerely.

Carlos L. Pena -S

Carlos L. Peña, PhD, MS Director Division of Neurological and Physical Medicine Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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## Indications for Use

510(k) Number (if known) K173352

Device Name

Trevo ProVue Retriever and Trevo XP ProVue Retriever (Trevo Retriever)

#### Indications for Use (Describe)

1. The Trevo Retriever is indicated for use to restore blood flow in the neurovasculature by removing thrombus for the treatment of acute ischemic stroke to reduce disability in patients with a persistent, proximal anterior circulation, large vessel occlusion, and smaller core infarcts who have first received intravenous tissue plasminogen activator (IV t-PA). Endovascular therapy with the device should start within 6 hours of symptom onset.

2. The Trevo Retriever is intended to restore blood flow in the neurovasculature by removing thrombus in patients experiencing ischemic stroke within 8 hours of symptom onset. Patients who are ineligible for intravenous tissue plasminogen activator (IV t-PA) or who fail IV t-PA therapy are candidates for treatment.

3. The Trevo Retriever is indicated for use to restore blood flow in the neurovasculature by removing thrombus for the treatment of acute ischemic stroke to reduce disability in patient, proximal anterior circulation, large vessel occlusion of the internal carotid artery (ICA) or middle cerebral artery (MCA)-M1 segments with smaller core infarcts (0-50 cc for age < 80 years, 0-20 cc for age ≥ 80 years). Endovascular therapy with the device should start within 6-24 hours of time last seen well in patients who are ineligible for intravenous tissue plasminogen activator (IV t-PA) or who fail IV t-PA therapy.

Type of Use (Select one or both, as applicable)

| <span style="font-family: DejaVu Sans, sans-serif">☑</span> Prescription Use (Part 21 CFR 801 Subpart D) | ☐ Over-The-Counter Use (21 CFR 801 Subpart C) |
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#### 510(k) Summary

| Trade Name: | Trevo ProVue Retriever and Trevo XP ProVue Retriever (Trevo Retriever) |
|-----------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Common Name: | Trevo Retriever |
| Classification Name: | Neurovascular Mechanical Thrombectomy Device for Acute<br>Ischemic Stroke Treatment, 21 CFR 882.5600, Class II, POL -<br>Percutaneous Catheter, 21CFR 870.1250, Class II, NRY |
| Product Code: | POL, NRY |
| Submitter: | Concentric Medical, Inc.<br>301 E. Evelyn Avenue<br>Mountain View, CA 94041<br>Tel [phone]<br>Fax [phone]<br>Facility Registration #2954917 |
| Contact: | Rhoda M. Santos<br>Senior Principal Regulatory Affairs Specialist |
| Date Prepared: | February 6, 2018 |
| Predicate Device: | Trevo ProVue Retriever and Trevo XP ProVue Retriever<br>(DEN150049) |
| Reference Predicate Device: | Trevo Retriever (K120961) |

#### Device Description

The Trevo Retriever family, including the Trevo ProVue and Trevo XP ProVue Retriever consists of a flexible, tapered core wire with a shaped section at the distal end. Platinum markers at the distal end allow fluoroscopic visualization. In addition, the shaped section is also radiopaque. Retriever dimensions are indicated on product label. The Retriever has a hydrophilic coating to reduce friction during use. The Retriever has a shaft marker to indicate proximity of Retriever tip relative to Microcatheter tip. A torque device is provided with the Retriever to facilitate manipulation. The torque device is used to lock the core wire to the microcatheter during the procedure. Locking of the torque device to the wire allows the microcatheter and Retriever to be retracted as a system during clot retrieval. An insertion tool is provided to introduce the Retriever into a Microcatheter. The Insertion Tool is a sheath in which the Retriever comes preloaded. Once half the retriever's length is inserted into the microcatheter, the insertion tool is removed. Retrievers have a modified proximal end that permits attachment of the Abbott Vascular DOC Guide Wire Extension (REF 22260). Joining Guide Wire Extension to Retriever facilitates removal or exchange of a catheter while maintaining Retriever position in anatomy. After exchange has been completed, the extension can be detached.

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#### Accessories

The Retriever is provided with two accessories: a torque device facilitates manipulation of the Retriever; and an insertion tool is used to introduce the Retriever into a microcatheter.

#### Indications for Use

The Indications for Use for the Trevo ProVue and Trevo XP ProVue Retrievers are as follows:

- 1. The Trevo Retriever is indicated for use to restore blood flow in the neurovasculature by removing thrombus for the treatment of acute ischemic stroke to reduce disability in patients with a persistent, proximal anterior circulation, large vessel occlusion, and smaller core infarcts who have first received intravenous tissue plasminogen activator (IV t-PA). Endovascular therapy with the device should start within 6 hours of symptom onset.
- 2. The Trevo Retriever is intended to restore blood flow in the neurovasculature by removing thrombus in patients experiencing ischemic stroke within 8 hours of symptom onset. Patients who are ineligible for intravenous tissue plasminogen activator (IV t-PA) or who fail IV t-PA therapy are candidates for treatment.
- 3. The Trevo Retriever is indicated for use to restore blood flow in the neurovasculature by removing thrombus for the treatment of acute ischemic stroke to reduce disability in patients with a persistent, proximal anterior circulation, large vessel occlusion of the internal carotid artery (ICA) or middle cerebral artery (MCA)-M1 segments with smaller core infarcts (0-50 cc for age < 80 years, 0-20 cc for age ≥ 80 years). Endovascular therapy with the device should start within 6-24 hours of time last seen well in patients who are ineligible for intravenous tissue plasminogen activator (IV t-PA) or who fail IV t-PA therapy.

#### Technological Characteristics and Product Feature Comparison

The Trevo ProVue and Trevo XP ProVue Retriever subject devices are identical to the predicate devices and differ only by the expanded indications for use.

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| Feature | Reference Predicate<br>Device<br>Trevo Retriever<br>(K120961) | Primary Predicate Device<br>Trevo ProVue Retriever and<br>Trevo XP ProVue Retriever<br>(DEN150049) | Subject Device<br>Trevo ProVue Retriever and<br>Trevo XP ProVue Retriever<br>with Expanded Indications | Rationale for<br>Modification (if<br>applicable) |
|-------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Intended Use | The Trevo Retriever is<br>intended to restore blood<br>flow in the<br>neurovasculature by<br>removing thrombus in<br>patients experiencing<br>ischemic stroke within 8<br>hours of symptom onset.<br>Patients who are ineligible<br>for intravenous tissue<br>plasminogen activator<br>(IV-tPA) or who fail IV t-<br>PA therapy are candidates<br>for treatment. | Neurovascular mechanical<br>thrombectomy device for acute<br>ischemic stroke treatment used<br>in the treatment of acute<br>ischemic stroke to improve<br>clinical outcomes. | Same | Not applicable. |
| Feature | Reference Predicate<br>Device<br>Trevo Retriever<br>(K120961) | Primary Predicate Device<br>Trevo ProVue Retriever and<br>Trevo XP ProVue Retriever<br>(DEN150049) | Subject Device<br>Trevo ProVue Retriever and<br>Trevo XP ProVue Retriever<br>with Expanded Indications | Rationale for<br>Modification (if<br>applicable) |
| Indications for<br>Use | The Trevo Retriever is<br>intended to restore blood<br>flow in the<br>neurovasculature by<br>removing thrombus in<br>patients experiencing<br>ischemic stroke within 8<br>hours of symptom onset.<br>Patients who are<br>ineligible for intravenous<br>tissue plasminogen<br>activator (IV-tPA) or who<br>fail IV t-PA therapy are<br>candidates for treatment. | The Trevo Retriever is<br>indicated for use to restore<br>blood flow in the<br>neurovasculature by removing<br>thrombus for the treatment of<br>acute ischemic stroke to reduce<br>disability in patients with a<br>persistent, proximal anterior<br>circulation, large vessel<br>occlusion, and smaller core<br>infarcts who have first received<br>intravenous tissue plasminogen<br>activator (IV-tPA).<br>Endovascular therapy with the<br>device should start within 6<br>hours of symptom onset. | 1. The Trevo Retriever is<br>indicated for use to restore<br>blood flow in the<br>neurovasculature by removing<br>thrombus for the treatment of<br>acute ischemic stroke to reduce<br>disability in patients with a<br>persistent, proximal anterior<br>circulation, large vessel<br>occlusion, and smaller core<br>infarcts who have first received<br>intravenous tissue plasminogen<br>activator (IV t-PA).<br>Endovascular therapy with the<br>device should start within 6<br>hours of symptom onset.<br>2. The Trevo Retriever is<br>intended to restore blood flow<br>in the neurovasculature by<br>removing thrombus in patients<br>experiencing ischemic stroke<br>within 8 hours of symptom<br>onset. Patients who are<br>ineligible for intravenous<br>tissue plasminogen activator<br>(IV t-PA) or who fail IV t-PA<br>therapy are candidates for<br>treatment.<br>3. The Trevo Retriever is<br>indicated for use to restore<br>blood flow in the<br>neurovasculature by removing<br>thrombus for the treatment of<br>acute ischemic stroke to reduce<br>disability in patients with a<br>persistent, proximal anterior<br>circulation, large vessel<br>occlusion of the internal<br>carotid artery (ICA) or middle<br>cerebral artery (MCA)-M1<br>segments with smaller core<br>infarcts (0-50 cc for age < 80<br>years, 0-20 cc for age ≥ 80<br>years). Endovascular therapy<br>with the device should start<br>within 6-24 hours of time last<br>seen well in patients who are<br>ineligible for intravenous<br>tissue plasminogen activator<br>(IV t-PA) or who fail IV t-PA<br>therapy. | The results of<br>DAWN study<br>(IDE G130223)<br>demonstrate that<br>the expanded<br>indications do not<br>raise any new or<br>different<br>questions of<br>safety or<br>effectiveness. |
| REGULATORY INFORMATION | | | | |
| Regulation<br>Number/<br>Name/ Class/<br>Product Code | 21 CFR 870.1250,<br>Percutaneous Catheter,<br>Class II, NRY | 21 CFR 882.5600,<br>Neurovascular Mechanical<br>Thrombectomy Device for<br>Acute Ischemic Stroke<br>Treatment, Class II, POL | Same | Not applicable. |
| Feature | Reference Predicate<br>Device<br>Trevo Retriever<br>(K120961) | Primary Predicate Device<br>Trevo ProVue Retriever and<br>Trevo XP ProVue Retriever<br>(DEN150049) | Subject Device<br>Trevo ProVue Retriever and<br>Trevo XP ProVue Retriever<br>with Expanded Indications | Rationale for<br>Modification (if<br>applicable) |
| Target<br>Population | Patients experiencing acute ischemic stroke | Patients experiencing acute ischemic stroke | Same | Not applicable. |
| Anatomical<br>Sites | Neurovasculature | Neurovasculature | Same | Not applicable. |
| | TECHNOLOGICAL CHARACTERISTICS | | | |
| Device<br>Description | The Retriever consists of<br>a flexible, tapered core<br>wire with a shaped section<br>at the distal end. A<br>platinum coil allows<br>fluoroscopic visualization.<br>The Retriever has a<br>hydrophilic coating to<br>reduce friction. The<br>Retriever has a shaft<br>marker to indicate<br>proximity of Retriever tip<br>relative to Microcatheter<br>tip. A torque device and<br>insertion tool are provided<br>with the Retriever. | The Retriever consists of a<br>flexible, tapered core wire with<br>a shaped section at the distal<br>end. Platinum markers at the<br>distal end allow fluoroscopic<br>visualization. In addition, the<br>shaped section is also<br>radiopaque. Retriever<br>dimensions are indicated on<br>product label. The Retriever has<br>a hydrophilic coating to reduce<br>friction during use. The<br>Retriever has a shaft marker to<br>indicate proximity of Retriever<br>tip relative to Microcatheter tip.<br>A torque device is provided<br>with the Retriever to facilitate<br>manipulation. The torque device<br>is used to lock the core wire to<br>the microcatheter during the<br>procedure. Locking of the<br>torque device to the wire allows<br>the microcatheter and Retriever<br>to be retracted as a system<br>during clot retrieval. An<br>insertion tool is provided to<br>introduce the Retriever into a<br>Microcatheter. The Insertion<br>Tool is a sheath in which the<br>Retriever comes preloaded.<br>Once half the retriever's length<br>is inserted into the<br>microcatheter, the insertion tool<br>is removed. Retrievers have a<br>modified proximal end that<br>permits attachment of the<br>Abbott Vascular DOC Guide<br>Wire Extension (REF 22260).<br>Joining Guide Wire Extension<br>to Retriever facilitates removal<br>or exchange of a catheter while<br>maintaining Retriever position<br>in anatomy. After exchange has<br>been completed, the extension<br>can be detached. | Same | Not applicable. |
| Principle of<br>Operation | The Trevo Retriever is delivered to the thrombus using a<br>microcatheter. The microcatheter is then retracted to deploy<br>the shaped section of the Retriever. The Retriever and<br>Microcatheter are pulled back to capture the thrombus. The<br>Retriever, thrombus and Microcatheter are then removed | Same | Not applicable. | |

Table 1: Product Feature Comparison of Subject Device to Predicate Device

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| Feature | Reference Predicate<br>Device<br>Trevo Retriever<br>(K120961) | Primary Predicate Device<br>Trevo ProVue Retriever and<br>Trevo XP ProVue Retriever<br>(DEN150049) | Subject Device<br>Trevo ProVue Retriever and<br>Trevo XP ProVue Retriever<br>with Expanded Indications | Rationale for<br>Modification (if<br>applicable) | | | | | | | | | | | | | | | | | | | | | | |
|----------------------------------------|---------------------------------------------------------------------|----------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------|--------------------------------------------------|--|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--------------------------------------------------------------------------------------------------|-----------------|
| Sizes | 4x20mm | 3x20mm, 4x20mm, 4x30mm,<br>6x25mm | Same | Not applicable. | | | | | | | | | | | | | | | | | | | | | | |
| Accessory<br>Devices | Insertion tool and torque device provided within product<br>package | Same | Not applicable. | | | | | | | | | | | | | | | | | | | | | | | |
| Microcatheter<br>(MC)<br>Compatibility | Retriever size Trevo 18<br>MC Trevo ProVue<br>4X20mm ✓ | | | | | Retriever<br>size Trevo<br>Pro14<br>MC Trevo<br>Pro18<br>MC Trevo XP<br>ProVue<br>3X20mm ✓ ✓ Trevo XP<br>ProVue<br>4X20mm ✓ Trevo<br>ProVue<br>4X20mm ✓ Trevo XP<br>ProVue<br>4X30mm ✓ Trevo XP<br>ProVue<br>6X25mm ✓ | | | | | | | | | | | | | | | | | | | Excelsior<br>® XT-<br>27®<br>Microcat<br>heters<br>(150cm x<br>6cm<br>straight<br>REF<br>275081) | Not applicable. |
| Materials | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Core Wire | Nitinol (nickel titanium alloy) | Same | Not applicable. | | | | | | | | | | | | | | | | | | | | | | | |
| Shaped Section | Nitinol | Same | Not applicable. | | | | | | | | | | | | | | | | | | | | | | | |
| Distal Coil | Platinum/Tungsten | Same | Not applicable. | | | | | | | | | | | | | | | | | | | | | | | |
| Shaped Section<br>Radiopaque<br>Wire | Not applicable. | Platinum/Tungsten | Same | Not applicable. | | | | | | | | | | | | | | | | | | | | | | |
| Proximal Coil | 304 Stainless Steel | Same | Not applicable. | | | | | | | | | | | | | | | | | | | | | | | |
| Solder | Gold/Tin | Same | Not applicable. | | | | | | | | | | | | | | | | | | | | | | | |
| Hydrophilic<br>Coating | Sodium hyaluronate mixture | Same | Not applicable. | | | | | | | | | | | | | | | | | | | | | | | |

#### Risk Assessment

Risk assessment of the modifications has been conducted in accordance with EN ISO 14971:2012. Concentric Medical, Inc. has determined that the expanded indications raise no new questions of safety or effectiveness. Results of clinical testing are appropriate for use in determining that the subject device is substantially equivalent to the predicate device.

The expanded indications did not result in the identification of any new failure modes nor were there any changes to existing failure modes, including no change to severity or occurrence; and, therefore, no change to overall residual risk.

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#### Leveraged Non-Clinical Data

Performance testing for the subject device is leveraged from the predicate device cleared under reclassification order DEN150049 and the reference predicate device cleared under K120961. The subject device (Trevo ProVue and Trevo XP ProVue Retrievers with Expanded Indications) differs from the predicate devices (DEN150049, K120961) only by the indications for use. The technological characteristics and principles of operation remain unchanged. There are no changes in the device design, materials, manufacturing, packaging and sterilization methods, therefore biocompatibility data, bench-top data, sterilization and stability data from the predicate devices (DEN150049, K120961) are directly applicable and no additional testing is required or was performed.

#### Clinical Data

The DAWN™ study (IDE G130223) was a multi-center, Bayesian adaptive-enrichment, prospective, randomized, open, masked endpoint trial, conducted in multiple countries to evaluate the safety and effectiveness of the subject device with the expanded indications. The data from the DAWN study constitutes the premarket clinical data required to demonstrate substantial equivalence with the predicate device.

#### Study Design

The DAWN study was designed to evaluate the hypothesis that Trevo thrombectomy plus medical management leads to superior clinical outcomes at 90 days as compared to medical management alone in appropriately selected subjects experiencing an acute ischemic stroke when treatment is initiated within 6-24 hours after last seen well; 90-day disability assessed by modified Rankin scale (mRS) is the primary endpoint.

The first co-primary analysis, based on the utility weighted (UW)-mRS, evaluated the posterior probability the Trevo thrombectomy increases expected scores relative to medical management alone, using a statistical model that adjusts for baseline core infarct volume. The threshold for success was a posterior probability of at least 0.986, increased from 0.975 to account for the potential for enrichment and different final sample sizes. The second co-primary analysis based on the dichotomized mRS (0-2 vs. 3-6) was conducted in the same model and carried out in a hierarchical fashion. The trial had 86% power to detect a UW-mRS difference of 1.0 between the treatment arms. Study success was predicated on simultaneous success of the co-primary endpoint analyses.

#### Key Inclusion Criteria

Acute ischemic stroke with confirmed occlusion of intracranial ICA and/or M1, that failed or were contraindicated for IV t-PA, treatment within 6-24 hours after time last known well, baseline NIHSS > 10, informed consent given and age 18 or over; In patients younger than 80, a stroke score equal to or greater than 10 must be associated with a core volume less than 51 ml. In patients 80 or older, the stroke score must be greater than 10 and volume less than 21 ml. Clinical-core mismatch which is defined as the mismatch between baseline infarct volume (or core) on CT or MRI imaging and the extent of total brain tissue at risk.

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### Key Exclusion criteria

Rapid improvement in neurological status to an NIHSS < 10 or evidence of vessel recanalization prior to randomization; Arterial blood pressure > 185/110 mmHg; laboratory evidence of electrolyte imbalance (i.e., sodium < 130 mmol/L, potassium < 3 mEq/L or > 6 mEq/L); laboratory evidence of renal failure (i.e., serum creatinine > 3.0 mg/dL (264 umol/L); laboratory evidence of coagulation abnormalities (i.e., platelet count < 50,000/uL, APTT > 3 times normal or INR > 3.0, if given factor Xa inhibitor 24-48 hours ago must have normal PTT); laboratory evidence of bleeding (i.e., hemoglobin < 7 mmol/L).

#### Primary Effectiveness Analysis

Study success was based on simultaneous success criteria of both the 90 day UW-mRS as well as the dichotomized 90 day mRS (0-2 vs. 3-6) of the ITT population. Table 2 shows the overall distribution and descriptive statistics of the 90 day mRS. In all analyses, outcomes for the Treatment arm were significantly better than the Control arm.

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| Modified Rankin Scale (mRS) | Treatment Arm<br>N=107 | Control Arm<br>N= 99 |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------|----------------------|
| 0 - No symptoms / UW = 10 | 9.3% (10/107) | 4.0% (4/99) |
| 1 - No significant disability / UW = 9.1 | 22.4% (24/107) | 5.1% (5/99) |
| 2 - Slight disability / UW = 7.6 | 16.8% (18/107) | 4.0% (4/99) |
| 3 - Moderate disability / UW = 6.5 | 13.1% (14/107) | 16.2% (16/99) |
| 4 - Moderately severe disability / UW<br>= 3.3 | 13.1% (14/107) | 34.3% (34/99) |
| 5 - Severe disability / UW = 0 | 6.5% (7/107) | 18.2% (18/99) |
| 6 - Dead / UW = 0 | 18.7% (20/107) | 18.2% (18/99) |
| 90 Day mRS [0-2] | 48.6% (52/107) | 13.1% (13/99) |
| 90 Day Weighted mRS** | | |
| Mean $\pm$ SD (N) | 5.5 $\pm$ 3.8 (107) | 3.4 $\pm$ 3.2 (99) |
| Median (Q1, Q3) | 6.5 (0.0, 9.1) | 3.3 (0.0, 6.5) |
| Range(min, max) | (0.0, 10.0) | (0.0, 10.0) |
| [95% Conf. Interval]¹ | [4.8, 6.3] | [2.7, 4.0] |
| ¹ By normal approximation<br>** mRS =(0,1,2,3,4,5,6) was assigned a corresponding numerical value =(10,9.1,7.6,6.5,3.3,0,0), which<br>represents its clinical utility | | |

Table 2: 90 Day Imputed Modified Rankin Scale ITT Population

Table 3 summarizes the co-primary outcomes. The mean value of UW-mRS was 5.5 in the Treatment group and 3.4 in the Control group. The core infarct adjusted posterior mean treatment benefit of the ITT analysis population was 2.04 with 95% Credible Interval 1.1 to 2.98. The Treatment arm had superior rates of functional independence at 90 days (48.6 % vs. 13.1%); core adjusted posterior treatment benefit of 32.8%, 95% Credible Interval 21.1% to 44.1%. The posterior probability of superiority for both coprimary endpoints was highly signi…