The AXIOS Stent and Electrocautery Enhanced Delivery System is indicated for use to facilitate transgastric or transquodenal endoscopic drainage of the gallbladder in patients with acute cholecystitis who are at high risk for surgery.

Device Description

The AXIOS Stent and Electrocautery-Enhanced Delivery system is designed to help facilitate the transgastric or transduodenal endoscopic drainage of the gallbladder. The AXIOS Stent remains identical to the stents cleared previously per K220112. The AXIOS Stent is a flexible, magnetic resonance conditional, fully covered, self-expanding, braided nitinol stent, which comes preloaded into the delivery system. The AXIOS stent is designed with two flanges, one on each end, to prevent migration and to enable tissue plane apposition and a "saddle" in between the flanges to span the tissue implant distance. The stent is fully covered with silicone to prevent leakage, discourage tissue in-growth within the nitinol woven braid, and facilitate removal. The AXIOS Electrocautery-Enhanced Delivery System consists of a catheter and an integrated handle with manual controls for positioning and deploying the AXIOS™ Stent. The AXIOS™ Electrocautery-Enhanced Delivery System is designed to be used in the gastrointestinal tract with commercially available echoendoscopes with a 3.7 mm diameter or larger working chamel and is compatible with commercially available 0.035-inch insulated endoscopic guidewires. The Electrocautery-Enhanced Delivery System connects with an off-the-shelf electrosurgical unit or generator that is compliant to IEC 60601-1-2 and IEC 60601-2-2.

AI/ML Overview

The provided text describes the acceptance criteria and the study that proves the AXIOS Stent and Electrocautery-Enhanced Delivery System meets those criteria. The information is primarily from non-clinical/bench testing and a pivotal clinical study, supplemented by a meta-analysis of clinical literature.

Here's the breakdown of the requested information:

Acceptance Criteria and Device Performance

1. Table of Acceptance Criteria and Reported Device Performance

The document presents two main categories of performance data: non-clinical/bench testing and clinical study results.

Table 1: Non-Clinical/Bench Testing Performance for AXIOS Stent and Delivery System

Test	Purpose	Acceptance Criteria	Reported Device Performance (Result)
Deployed Stent Saddle Length	Verify dimensions of deployed stent	Deployed Stent Saddle Length (inside flange to inside flange) @37°C $\geq$ 8.5 mm $\leq$ 13 mm for both AXIOS 10 mm x 10 mm & AXIOS 15 mm x 10 mm	Pass
Deployed Stent Saddle Outer Diameter	Verify dimensions of deployed stent	AXIOS 10mm x 10 mm stent: $\geq$ 8 mm; AXIOS 15mm x 10mm stent: $\geq$ 13 mm	Pass
Deployed Stent Flange Width	Verify dimensions of deployed stent	AXIOS 10 mm x 10 mm: $\geq$ 3 mm; AXIOS 15 mm x 10 mm: $\geq$ 3 mm	Pass
Stent Pull-Out Force	Verify stent will remain in place when pull-out force is applied	AXIOS 10 mm x 10 mm: $\geq$ 2.54 N; AXIOS 15 mm x 10 mm stent: Not explicitly stated, implied same as 10mmx10mm via "Pass" result column.	Pass
Stent (Saddle) Radial Strength – Compression & Expansion	Verify expansion strength of the compressed stent meets product specification	In compression @ 37°C $\geq$ 0.06 N/mm of length @ 50% Ø; In expansion @ 37°C $\geq$ 0.02 N/mm of length @ 50% Ø (for both AXIOS 10mm x 10 mm and 15 mm x 10 mm)	Pass
Deployment (Unsheathing) Force	Verify force needed to deploy stent	AXIOS 10 mm x 10 mm: $\leq$ 40 N; AXIOS 15 mm x 10 mm stent: $\leq$ 40 N	Pass
Implant Anchor Function – Retention (Tensile)	Verify force needed to achieve apposition of distal flange to target structure	AXIOS 10 mm x 10 mm: $\geq$ 2 N; AXIOS 15 mm x 10 mm stent $\geq$ 2 N	Pass
Magnetic Resonance Testing	Verify stent will not prevent ability to use MRI	The stent should not prevent the ability of the physician to use Magnetic Resonance Imaging on the patient.	Pass
Fatigue Testing	Ensure stent remains intact throughout the period of use	The stent must remain intact after 940,000 translation (distal flange with respect to proximal flange) cycles.	Pass
Corrosion Testing	Evaluate corrosion resistance of stent	The metal stent and stent covering must show corrosion resistance when subjected to an in vitro corrosive environment equivalent to sixty days.	Pass
Delivery System Working Length	Verify working length of delivery device	Working Length (distal point of the handle to distal end of the catheter tip) $\leq$ 138 cm	Pass
Slider lock hold force testing	Evaluate performance of lock under compressional and torsional forces	Lock hold force $\geq$ 22 N	Pass
Nose lock hold force	Evaluate performance of lock under compressional and torsional forces	Lock hold force $\geq$ 22 N	Pass
Nose/slide lock cycling	Inspect function of nose/slide lock feature	Nose lock must function after 6 cycles; slide lock must function after 4 cycles.	Pass
Joint Strength Testing	Verify joint strength meets design requirements	Per EN ISO 10555-1, the device shall meet specific minimum force.	Pass
Luer to Nose Joint Strength	Verify peak tensile force of luer to nose joint	Luer to Nose Joint Strength $\geq$ 22 N	Pass
Outer Sheath to Handle Torque Strength	Verify ability of AXIOS catheter to withstand torque when the device is rotated 360°	The catheter system must withstand a minimum of 1 full turn.	Pass
Tracking Force	Verify tracking force of outer sheath through a 3.7 mm working channel	Track force $\leq$ 8.83 N	Pass

Table 2: Clinical Study Performance (Pivotal Study and Meta-Analysis)

Endpoint/Outcome	Acceptance Criteria (Performance Goal)	Reported Device Performance (Pivotal Study, N=30 ITT)	Reported Device Performance (Meta-Analysis, N=713 combined)
Primary Effectiveness: Days to resolution of Acute Cholecystitis (AC)	$< 3.5$ days (upper bound of 97.8% one-sided CI)	Primary Analysis (ITT, censored): Mean 5.30 $\pm$ 14.90 days. 97.8% one-sided CI [0.00, 10.78]. Failed acceptance criteria on this specific analysis using censoring. Additional Analysis (ITT, all patients observed): Mean 1.60 $\pm$ 1.50 days. 97.8% one-sided CI [0.0, 2.15]. Met acceptance criteria. Treated/Per-Protocol (N=28): Mean 1.39 $\pm$ 0.92 days. 97.8% one-sided CI [0.0, 1.74]. Met acceptance criteria.	Not applicable (this specific endpoint was not directly reported in the meta-analysis in the same way).
Secondary Effectiveness: Rate of re-intervention (migration/occlusion)	$< 46.2$% (upper bound of 99.7% one-sided CI)	ITT Patients (N=30): 16.7% (5/30). 99.7% one-sided CI [0.0%, 42.0%]. Met acceptance criteria. Treated/Per-Protocol Patients (N=28): 14.3% (4/28). 99.7% one-sided CI [0.0%, 40.2%]. Met acceptance criteria.	10.3% (2.6%, 22.1%) - Broader definition of re-interventions likely.
Additional Endpoints: Technical success (stent placement with patency)	Not explicitly stated (implied high percentage)	ITT Patients (N=30): 93.3% (28/30). 97.9% CI [77.9%, 99.2%].	97.0% (95.1%, 98.5%)
Technical stent removal success	Not explicitly stated (implied high percentage)	Attempted (N=19): 100% (19/19). 95% CI [82.4%, 100.0%].	Not directly reported in meta-analysis.
Stent patency at stent removal visit	Not explicitly stated (implied high percentage)	Assessed (N=22): 100% (22/22). 95% CI [84.6%, 100.0%].	Not directly reported in meta-analysis.
Recurrence of acute cholecystitis symptoms	Not explicitly stated (implied low percentage)	ITT Patients (N=30): 10.0% (3/30). 95% CI [2.1%, 26.5%].	1.8% (0.4%, 4.2%)
Clinical Success	Not explicitly stated (implied high percentage)	Not directly defined as a primary or secondary endpoint with a specific numerical goal in the pivotal study. The "Symptom resolution" primary endpoint implies clinical success.	92.0% (89.2%, 94.3%)
Procedure Related AEs	Not explicitly stated (implied low percentage)	3.6% (4/111 of AEs at procedure), 0.0% (0/11 of related AEs). The overall rate of related AEs was 30% (9/30 subjects) with a count of 11 related AEs.	12.0% (8.5%, 16.0%)
Overall AEs	Not explicitly stated (implied low percentage)	93.3% (28/30 subjects). Total AEs: 111. SAEs: 35. One SAE was related to the device/procedure.	22.7% (17.5%, 28.4%)

2. Sample Sizes Used for the Test Set and Data Provenance

Pivotal Clinical Study (Test Set):
- Sample Size: 30 subjects (Intent-to-Treat, ITT). 28 subjects formed the Treated/Per-protocol cohort.
- Data Provenance: The study was a "Multicenter, Prospective Study" (from G170190), indicating it was a forward-looking study where data was collected specifically for this evaluation. The document does not explicitly state the country of origin, but Boston Scientific Corporation is based in Marlborough, Massachusetts, USA, suggesting a likely multi-site international or US-based study framework.
Meta-Analysis of Clinical Literature:
- Sample Size: 17 articles encompassing 713 patients.
- Data Provenance: Retrospective, derived from published literature from various sources. One notable included study was a "randomized multicentre controlled superiority trial (DRAC 1)" (Teoh et al., Gut, 2020) which compared the AXIOS stent to percutaneous cholecystostomy, providing prospective, comparative data within the meta-analysis.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications

The document does not provide information regarding the number of experts or their specific qualifications (e.g., radiologists with X years of experience) used to establish ground truth for the clinical study data. It is a clinical trial setting, so subject outcomes, diagnoses, and adverse events would be determined by the treating physicians and study staff according to study protocols, often involving standard clinical diagnostic criteria and adjudication by a clinical events committee, though none of these details are given in the provided text.

4. Adjudication Method for the Test Set

The document does not explicitly describe a formal adjudication method (e.g., 2+1, 3+1) for the primary and secondary endpoints in the pivotal study. Clinical trials typically have predefined methods for recording and verifying endpoints and adverse events, often involving a clinical events committee (CEC), but these specific details are not provided. The determination of "symptom resolution" was based on objective clinical measures (temperature, pain score, WBC).

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This type of study typically assesses the performance of human readers with and without AI assistance on medical images. The AXIOS Stent is a medical device for drainage, not an imaging diagnostic AI device.

6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study

This question is not applicable in the context of this device. The AXIOS stent is a physical medical device and delivery system, not an AI algorithm. Its performance is evaluated through bench testing and clinical outcomes, reflecting the device's function directly and its interaction with human operators (physicians) during placement and use.

7. The Type of Ground Truth Used

For Non-Clinical/Bench Studies: The ground truth was established by physical measurements, standardized test methods (e.g., ASTM, EN ISO standards), and direct observation against predefined engineering specifications and performance criteria.
For the Pivotal Clinical Study: The ground truth for effectiveness endpoints (e.g., symptom resolution, re-intervention) was based on clinical outcomes data from the patients enrolled in the prospective study, including physiological parameters (temperature, WBC), patient-reported pain scores, physician assessments of stent patency, and documented adverse events.
For the Meta-Analysis: The ground truth was based on the reported outcomes from published clinical literature, which would similarly derive from clinical assessments, diagnostic findings, and patient outcomes within those individual studies.

8. The Sample Size for the Training Set

This question is not applicable. The AXIOS stent is a physical medical device, not an AI algorithm that requires a "training set" for machine learning. The term "training set" is relevant for AI/ML model development.

9. How the Ground Truth for the Training Set Was Established

This question is not applicable, as there is no "training set" in the context of this device's development or evaluation as described.

Summary

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DE NOVO CLASSIFICATION REQUEST FOR AXIOS STENT AND ELECTROCAUTERY-ENHANCED DELIVERY SYSTEM (10 MM X 10 MM STENT); AXIOS STENT AND ELECTROCAUTERY-ENHANCED DELIVERY SYSTEM (15 MM X 10 MM STENT)

REGULATORY INFORMATION

FDA identifies this generic type of device as:

Gallbladder drainage stent and delivery system. A gallbladder drainage stent is a prescription device intended to facilitate transgastric or transduodenal endoscopic drainage of the gallbladder. This device may also include a delivery system.

NEW REGULATION NUMBER: 21 CFR 876.5016

CLASSIFICATION: Class II

PRODUCT CODE: QXH

BACKGROUND

DEVICE NAME: AXIOS Stent and Electrocautery-Enhanced Delivery System (10 mm x 10 mm Stent); AXIOS Stent and Electrocautery-Enhanced Delivery System (15 mm x 10 mm Stent)

SUBMISSION NUMBER: DEN230019

DATE DE NOVO RECEIVED: March 27, 2023

SPONSOR INFORMATION:

Boston Scientific Corporation 100 Boston Scientific Way Marlborough, Massachusetts 01752

INDICATIONS FOR USE

The AXIOS Stent and Electrocautery-Enhanced Delivery System (10 mm x 10 mm Stent); AXIOS Stent and Electrocautery-Enhanced Delivery System (15 mm x 10 mm Stent) is indicated as follows:

LIMITATIONS

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The sale, distribution, and use of the AXIOS Stent and Electrocautery-Enhanced Delivery System (10 mm x 10 mm Stent); AXIOS Stent and Electrocautery-Enhanced Delivery System (15 mm x 10 mm Stent are restricted to prescription use in accordance with 21 CFR 801.109.

Placement of the AXIOS Stent should be performed by physicians familiar with endoscopic ultrasonography and who have received training for AXIOS Stent placement techniques.

PLEASE REFER TO THE LABELING FOR A COMPLETE LIST OF WARNINGS. PRECAUTIONS AND CONTRAINDICATIONS.

DEVICE DESCRIPTION

The AXIOS Stent is a flexible, magnetic resonance conditional, fully covered, self-expanding, braided nitinol stent, which comes preloaded into the delivery system. The AXIOS stent is designed with two flanges, one on each end, to prevent migration and to enable tissue plane apposition and a "saddle" in between the flanges to span the tissue implant distance (Figure 1), The stent is fully covered with silicone to prevent leakage, discourage tissue in-growth within the nitinol woven braid, and facilitate removal.

Image /page/1/Figure/6 description: The image shows two views of a medical stent labeled as "Figure 1: AXIOS(TM) Stent". On the left, the stent is viewed from the side, showing its hourglass shape with labels indicating "Flange Diameter", "Saddle Length", and "Lumen Diameter". On the right, the stent is viewed head-on, revealing its circular structure and the "Drainage Lumen" in the center.

Figure 1: AXIOS M Stent

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Description	Stent Size			Delivery
	LumenDiameter	SaddleLength	FlangeDiameter	SystemOuterDiameter
AXIOS Stent and Electrocautery-EnhancedDelivery System(10mm x 10mm Stent)	10 mm	10 mm	21 mm	10.8 Fr
AXIOS Stent and Electrocautery-EnhancedDelivery System(15mm x 10mm Stent)	15 mm	10 mm	24 mm	10.8 Fr

The following stent sizes are included in this submission:

The AXIOS Electrocautery-Enhanced Delivery System consists of a catheter and an integrated handle with manual controls for positioning and deploying the AXIOS™ Stent. The AXIOS™ Electrocautery-Enhanced Delivery System is designed to be used in the gastrointestinal tract with commercially available echoendoscopes with a 3.7 mm diameter or larger working chamel and is compatible with commercially available 0.035-inch insulated endoscopic guidewires.

The Electrocautery-Enhanced Delivery System connects with an off-the-shelf electrosurgical unit or generator that is compliant to IEC 60601-1-2 and IEC 60601-2-2.

Image /page/2/Figure/4 description: The image shows a medical device with several labeled parts. The device includes components such as a 'Luer Lock,' 'Catheter Lock,' 'Stent Lock,' 'Safety Clip,' and 'Monopolar Plug.' The labels point to specific areas of the device, providing a clear understanding of its structure and function.

Figure 2: Electrocantery Enhanced AXIOS Delivery System Handle

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Image /page/3/Picture/0 description: The image shows a medical device, possibly an endoscope or a similar instrument used for minimally invasive procedures. The device has a long, flexible tube extending from a handle with controls. The handle appears to have a grip and adjustment mechanisms, suggesting it is used to manipulate the distal end of the tube for navigation and operation within the body.

Figure 3: Electrocantery Enhanced AXIOSTM Delivery System

SUMMARY OF NONCLINICAL/BENCH STUDIES

The performance of the AXIOS Stent and Delivery System was evaluated using the testing described in Table 1 below.

Test	Purpose	Method	Acceptance Criteria	Results
Deployed StentSaddle Length	Verify dimensions ofdeployed stent	Measuredeployed stent	Deployed Stent SaddleLength (inside flangeto inside flange)@37°C$\geq$ 8.5 mm ≤ 13 mmFor both theAXIOS 10 mm x 10mmAXIOS 15 mm x 10mm	Pass
Deployed StentSaddle OuterDiameter	Verify dimensions ofdeployed stent	Measuredeployed stent	Deployed Stent SaddleOuter Diameter @37°CAXIOS 10mm x 10 mmstent: $\geq$ 8 mm	Pass
Test	Purpose	Method	Acceptance Criteria	Results
			AXIOS 15mm x 10mmstent: ≥ 13 mm
Deployed StentFlange Width	Verify dimensions ofdeployed stent	Measuredeployed stent	Deployed FlangeWidth @ 37°CAXIOS 10 mm x 10mm: ≥ 3 mmAXIOS 15 mm x 10mm: ≥ 3 mm	Pass
Stent Pull-Out Force	Verify stent will remain inplace when pull-out force isapplied	Deploy stent intotest fixture. Pullstent until eitherstent flange slipsthrough orifice.	AXIOS 10 mm x 10mm: ≥ 2.54 N	Pass
Stent (Saddle) RadialStrength –Compression &Expansion	Verify expansion strengthof the compressed stentmeets product specification	Compress stentusing forcegauge. Measureforce at 50%reduction oforiginal stentdiameter.	AXIOS 10mm x 10 mmand 15 mm x10 mm:Stent (Saddle) RadialStrength – incompression @ 37°C ≥0.06 N/mm of length @50% Ø.AXIOS 10 mm x 10mm and 15 mm x 10mm: Stent (Saddle)Radial Strength – inexpansion @ 37°C ≥0.02 N/mm oflength @ 50% Ø.	Pass
Deployment(Unsheathing) Force	Verify force needed todeploy stent	Measuredeploymentforce of stentusing forcegauge.	AXIOS 10 mm x 10mm: Stent DeploymentForce≤ 40 N(AXIOS) 15 mm x 10mm stent: StentDeployment Force ≤ 40N	Pass
Implant AnchorFunction – Retention(Tensile)	Verify force needed toachieve apposition of distalflange to target structure	Measure force topull stentthroughsimulated testfixture	AXIOS 10 mm x 10mm: ≥ 2 N(AXIOS) 15 mm x 10mm stent ≥ 2 N	Pass
Magnetic ResonanceTesting	Verify stent will notprevent ability to use MRI	Testing perASTM F2182,ASTM 2119,	The stent should notprevent the ability of thephysician to use	Pass
Test	Purpose	Method	Acceptance Criteria	Results
		ASTM F2052,ASTM F2213,ASTM F2503	Magnetic ResonanceImaging on the patient
Fatigue Testing	Ensure stent remains intactthroughout the period ofuse	Test stents infatigue testerwith off-axisdisplacement of2 mm	The stent must remainintact after 940,000translation (distal flangewith respect to proximalflange) cycles.	Pass
Corrosion Testing	Evaluate corrosionresistance of stent	Test inaccordance withASTM F2129	The metal stent andstent covering mustshow corrosionresistance whensubjected to an in vitrocorrosive environmentequivalent to sixty days	Pass
Delivery SystemWorking Length	Verify working length ofdelivery device	Measure lengthof device	Working Length (distalpoint of the handle todistal end of the cathetertip) ≤ 138 cm	Pass
Slider lock hold forcetesting	Evaluate performance oflock under compressionaland torsional forces	Measuredisplacement ofcatheter afterapplying 5 lbf ofcompression/tension to lockedproximal hub	Lock hold force ≥ 22 N	Pass
Nose lock hold force	Evaluate performance oflock under compressionaland torsional forces	Measuredisplacement ofcatheter afterapplying 5 lbf ofcompression/tension to lockedproximal hub	Lock hold force ≥ 22 N	Pass
Nose/slide lockcycling	Inspect function ofnose/slide lock feature	Lock and unlocknose/slide lockfor apredeterminednumber of cycles	Nose lock must functionafter 6 cycles; slide lockmust function after 4cycles	Pass
Joint Strength Testing	Verify joint strength meetsdesign requirements	Test methods perEN ISO 10555-1	Per EN ISO 10555-1,the device shall meetspecific minimum force	Pass
Luer to Nose JointStrength	Verify peak tensile force ofluer to nose joint	Load deliverysystem into test	Luer to Nose JointStrength ≥ 22 N	Pass
Test	Purpose	Method	Acceptance Criteria	Results
		setup and applyforce until luerto nose jointfails. Recordpeak force.
Outer Sheath toHandle TorqueStrength	Verify ability of AXIOScatheter to withstand torquewhen the device is rotated360°	Rotate devicehandle 360degreesclockwise whileholdingproximal end ofhandle assembly.	The catheter systemmust withstand aminimum of 1 full turn.	Pass
Tracking Force	Verify tracking force ofouter sheath through a 3.7mm working channel	Load catheterinto stomachmodel andmeasure forcewhen tip ofsheath exitsmodel	Track force $≤$ 8.83 N	Pass

Table 1. Performance Testing for AXIOS Stent and Delivery System

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BIOCOMPATIBILITY/MATERIALS

The AXIOS Stent is defined as an implanted, tissue/bone contacting device with a contact duration greater than 30 days. Biocompatibility was evaluated in accordance with ISO 10993-1, Biological evaluation of medical devices and FDA Guidance: Use of International Standard 1SO 10993-1, "Biological evaluation of medical devices - Part 1: Evaluation and testing within a risk management process." The following biocompatibility endpoints were evaluated:

Cytotoxicity .
Sensitization .
Irritation .
Acute Systemic Toxicity .
Genotoxicity .
. Implantation

The AXIOS Delivery Device is defined as an externally communicating, tissue/bone contacting device with a contact duration less than 24 hours. The following biocompatibility endpoints were evaluated:

. Cytotoxicity
Sensitization .
Intracutaneous reactivity .
Material mediated pyrogenicity .
. Acute systemic toxicity

The provided biocompatibility data help demonstrate the biocompatibility of the device.

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SHELF LIFE/STERILITY

The AXIOS Stent and Delivery System are single use devices that are sterilized with ethylene oxide. The sterilization methods, location, and packaging integrity information are the same as referenced in K220112 and K192043. Sterilization data on a new, alternative sterilization cycle was also provided. The new sterilization method was found acceptable.

SUMMARY OF CLINICAL INFORMATION

Clinical data from a single-arm pivotal study (from G170190) and data from literature sources were leveraged to help evaluate the safety and effectiveness of the AXIOS Stent and Delivery System.

PIVOTAL STUDY DATA

In the pivotal study (A Multicenter, Prospective Study of (endoscopic ultrasound) EUS-Guided Transluminal Gallbladder Drainage in Patients with Acute Cholecystitis as an Alternative to Percutaneous Gallbladder Drainage), thirty subjects who are at high risk or unsuitable for surgery were enrolled with grade I or II Acute Cholecystitis received an AXIOS stent for drainage of the gallbladder as an alternative to percutaneous cholecystostomy. The AXIOS stent was removed between 30 and 60 days unless AXIOS stent removal was not medically indicated.

Primary Effectiveness Endpoints

. Symptom resolution:
- o temperature < 100.5ºF
- o 4-point decrease in pain score or
- o white blood cell <12.000 cc

with improvement in at least two categories without deterioration in the third category

Secondary Effectiveness Endpoints

. Reintervention, migration, or occlusion

Additional Endpoints

AXIOS stent placement: successful stent placement with confirmed stent patency .
AXIOS stent removal: successful endoscopic stent removal without stent removal-related . serious adverse events (SAE)s
Stent patency at stent removal visit .
Recurrence of acute cholecystitis symptoms .
. Reintervention visit
72-hour post-stent removal visit .
Final study visit .
Days hospitalized (between index procedure and stent removal visit / end of study) .

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Table 2. Subject Demographics

Variable	ITT Patients(N=30)
Age (yr)	$75.2\pm14.1(30)$(34.0,94.0)
Female	36.7% (11/30)
Male	63.3% (19/30)
Weight (kg)	$76.4\pm17.8(30)$(43.4,120.0)
Height (cm)	$168.6\pm9.4(30)$(147.0,182.9)
BMI (kg/m²)	$26.9\pm6.3(30)$(18.2,44.1)

Above numbers are mean + standard deviation (min, max).

Variable	ITT Patients(N=30)
Ethnicity
Hispanic or Latino	0.0% (0/30)
Not Hispanic or Latino	100.0% (30/30)
Not disclosed	0.0% (0/30)
Race
American Indian or Alaskan native	0.0% (0/30)
Asian	0.0% (0/30)
Black or African American	0.0% (0/30)
Hispanic or Latino	0.0% (0/30)
Native Hawaiian or other pacific islander	0.0% (0/30)
White (Caucasian)	100.0% (30/30)
Not disclosed	0.0% (0/30)

Study results are presented in Table 3 below. The endpoints are presented for the intent to treat (ITT) cohort (N=30), and for the treated and per protocol (PP) cohorts (N=28), which contained the same patients.

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Variable	ITT Patients(N=30)	Treated/PPPatients(N=28)
Primary Effectiveness Endpoint
Symptom resolution: temp <100.5°F, 4-point decrease inpain score or WBC<12,000 cc with improvement in atleast 2 categories without deterioration in the thirdcategory
Primary Analysis: Patients with no AXIOST™ stentimplanted counted as failure for resolution of acutecholecystitis (AC) and censored at 60 days	93.3% (28/30)[77.9%, 99.2%]	100.0% (28/28)[87.7%, 100.0%]
Days to resolution [97.8% 1-sided CI]	$5.30\pm14.90$ (30)(1.00, 60.00)[0.0, 10.78]	$1.39\pm0.92$ (28)(1.00, 5.00)[0.0, 1.74]
Additional Analysis: Resolution of AC counted for allpatients regardless of AXIOST™ stent implant	100.0% (30/30)[88.4%, 100.0%]	100.0% (28/28)[87.7%, 100.0%]
Days to resolution [97.8% 1-sided CI]	$1.60\pm1.50$ (30)(1.00, 8.00)[0.0, 2.15]	$1.39\pm0.92$ (28)(1.00, 5.00)[0.0, 1.74]
Secondary Effectiveness Endpoint

Table 3. Summary of Primary, Secondary, and Additional Endpoints for Clinical Study

Variable	ITT Patients(N=30)	Treated/PPPatients(N=28)
Reintervention, migration, or occlusion [99.7% 1-sided CI]	16.7% (5/30)[0.0%, 42.0%]	14.3% (4/28)[0.0%, 40.2%]
Additional Endpoints
Technical success
AXIOST™ stent placement: successful stentplacementwith confirmed stent patency	93.3% (28/30)[77.9%, 99.2%]	100.0% (28/28)[87.7%, 100.0%]
AXIOST™ stent removal: successful endoscopicstentremoval without stent removal-related SAEs	100.0% (19/19)[82.4%, 100.0%]	100.0% (19/19)[82.4%, 100.0%]
Stent patency at stent removal visit	100.0% (22/22)[84.6%, 100.0%]	100.0% (22/22)[84.6%, 100.0%]
Recurrence of acute cholecystitis symptoms	10.0% (3/30)[2.1%, 26.5%]	10.7% (3/28)[2.3%, 28.2%]
Reintervention visit	3.3% (1/30)[0.1%, 17.2%]	3.6% (1/28)[0.1%, 18.3%]
72-hour post-stent removal visit	0.0% (0/20)[0.0%, 16.8%]	0.0% (0/20)[0.0%, 16.8%]
Final study visit	7.7% (2/26)[0.9%, 25.1%]	8.3% (2/24)[1.0%, 27.0%]

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	$8.30\pm7.14 (30)$	$8.64\pm7.28 (28)$
Days hospitalized (between index procedure and stentremoval visit / end of study)	(3.00, 38.00)[5.74, 10.86]	(3.00, 38.00)[5.95, 11.34]

Numbers are: mean±standard deviation (N) (min, max) [confidence interval] for continuous variables or % (count/sample size) [confidence interval] for binary variables. All confidence intervals are two-sided 95% unless otherwise specified.

Primary Effectiveness Endpoint: For the Primary Analysis of the Primary Effectiveness Endpoint of Days to Resolutions of Acute Cholecystitis on the intend-to-treat (ITT) cohort (N=30), 2 ITT patients who did not receive an AXIOS stent were censored at 60 days as specified in the protocol. A mean ± standard deviation of days to resolution of 5.30±14.90 with a one-sided 97.8% confidence interval of [0.00, 10.78] was observed. Since the upper bound of the 97.8% confidence interval (10.78 days) was greater than the Performance Goal of 3.5 days, the null hypothesis that the mean days to resolution >3.5 days cannot be rejected and thus the endpoint has failed.

The two patients who did not receive an AXIOS stent were followed until resolution of Acute Cholecystitis. We also evaluated the Primary Effectiveness Endpoint using the observed days to Acute Cholecystitis resolution regardless of AXIOS stent implantation. For this additional analysis, 1.60±1.50 days to resolution of Acute Cholecystitis for the 30 ITT patients with 97.8% one-sided confidence interval of [0.0, 2.15] was observed. Since the upper bound of the 97.8% confidence interval of the mean days to resolution of Acute Cholecystitis was 2.15 days. which is less than the Performance Goal of 3.5 days, this analysis rejects the null hypothesis in favor of the alternative hypothesis that days to resolution of Acute Cholecystitis is less than 3.5 days.

For the treated/per-protocol cohorts (N=28), both the Primary and additional analyses vielded the same results of 1.39±0.92 days to resolution of Acute Cholecystitis (one-sided 97.8% confidence interval [0.0, 1.74]).

Since the upper bound of the 97.8% confidence interval (1.74 days) is less than the Performance Goal of 3.5 days, the null hypothesis is rejected in favor of the alternative hypothesis that days to resolution of Acute Cholecystitis is <3.5 days.

The different analyses for the primary effectiveness endpoint are summarized below:

CohortDescription	Time to Resolution of AC	Days toResolution ± SD[97.8% CI]
30 ITT subjects	As reported for 28 subjects who receivedAXIOS stent and 60 days for 2 subjects who didnot receive the AXIOS stent	$5.30\pm14.90$[0.00, 10.78]
30 ITT subjects	As reported for all 30 subjects	$1.60\pm1.50$[0.0, 2.15]

Table 1: Resolution of Acute Cholecystitis (AC)

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28 Treated/PerProtocol subjects	As reported for 28 subjects who received AXIOSstent	$1.39\pm0.92$[0.0, 1.74]
-------------------------------------	---------------------------------------------------------	------------------------------

Secondary Effectiveness Endpoint - Rate of re-interventions:

There were 10 re-interventions in 8 patients. These re-interventions can be categorized as follows:

· 1 patient with one re-intervention not affecting the biliary tract
2 patients with 2 re-interventions affecting the biliary tract for the management of . unrelated confirmed malignant biliary stenosis
5 patients with 7 re-interventions affecting the biliary tract for reasons other than the . management of confirmed malignant biliary stenosis.

Only the 7 re-interventions affecting the biliary tract for reasons other than confirmed malignant biliary stenosis were counted towards the Secondary Effectiveness Endpoint.

The Secondary Effectiveness Endpoint of rate of reintervention including migration or occlusion was observed to be 16.7% (5/30) for ITT patients (one-sided 99.7% confidence interval [0.0, 42.0%]). The upper bound of the 99.7% confidence interval of rate of reintervention is 42.0%, which is less than the Performance Goal of 46.2%. Thus, for this analysis the null hypothesis is rejected in favor of the alternative hypothesis that the rate of reintervention is <46.2%.

The treated and per-protocol cohorts had the same results for the Secondary Effectiveness Endpoint of 14.3% (4/28) of patients (one-sided 99.7% confidence interval [0.0, 40.2%]). The upper bound of the99.7% confidence interval of rate of reintervention is 40.2%, which is less than the Performance Goal of 46.2%. Thus, for this analysis the null hypothesis is rejected in favor of the alternative hypothesis that the rate of reintervention is <46.2%.

Additional Endpoints

Stent patency

Stent patency was observed for 100% (22/22) of patients in whom patency was assessed at the Stent Removal visit.

Technical stent placement success

Technical stent placement was observed for 93.3% (28/30) patients. For two patients. the AXIOS™ stent could not be implanted successfully in the gallbladder as discussed in Section 3.

Technical stent removal success

Stent removal was attempted for 19 patients and was successful for all 19 thus technical stent removal success is 100% (19/19).

Rate of recurrence of acute cholecystitis

There were three cases of recurrence of acute cholecystitis, all cases were after resolution of the baseline acute cholecystitis and after removal of the AXIOS™ stent. One recurrent acute

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cholecystitis (0859G009) was identified during a reintervention for stone removal 15 days after AXIOSTM removal.

One recurrent acute cholecystitis was reported at the final study visit 6 weeks after AXIOS™ removal and was managed with a cholecystectomy. The other recurrent acute cholecystitis case was reported 20 days after AXIOS™ stent removal and was associated with migration of plastics stents placed at the time of the AXIOSTM stent removal. This patient died one day later.

Number of cumulative hospital and ICU days

The mean ± standard deviation of the number of cumulative hospital days from the index procedure to the final study visit was 8.0±6.9 days. The number of ICU days was not collected.

Adverse Events

There have been no unanticipated adverse events (AEs) reported in this study. There have been 111 AEs of which 35 were recorded as SAEs.

One SAE was reported as related to the AXIOS™ Stent and AXIOS™ Stent placement procedure. This event led to death. There were ten non-serious AEs related to the AXIOS Stent, stent placement procedure and/or stent removal.

Variable	All AEs	Related toAXIOS™ stent,AXIOS™ stentplacement orremovalprocedure
Count	111	11
% Subjects	93.3% (28/30)	30.0% (9/30)
# AEs / Subjects	3.7±3.0 (30)(0.0, 13.0)	0.4±0.6 (30)(0.0, 2.0)
Days to onset	30.4±39.9 (111)(-6.0, 366.0)	19.8±20.7 (11)(0.0, 56.0)
Days to Resolution	9.2±17.1 (68)(0.0, 84.0)	4.7±6.3 (7)(0.0, 18.0)
Visit when AE occurred
Stent placement procedure	3.6% (4/111)	0.0% (0/11)
Daily acute cholecystitis assessment visit	24.3% (27/111)	45.5% (5/11)
Study stent removal	11.7% (13/111)	27.3% (3/11)
72-hour post-study stent removal visit	0.9% (1/111)	0.0% (0/11)
Final study visit	10.8% (12/111)	0.0% (0/11)
Reintervention visit	2.7% (3/111)	0.0% (0/11)
Unscheduled visit	45.9% (51/111)	27.3% (3/11)
Severity
Mild	59.5% (66/111)	63.6% (7/11)

Table 4. Summary of Adverse Events

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Moderate	27.9% (31/111)	27.3% (3/11)
Severe	12.6% (14/111)	9.1% (1/11)
Unknown	0.0% (0/111)	0.0% (0/11)
SeriousYes	31.5% (35/111)	9.1% (1/11)

The numbers in the table above are defined as follows:

% Subjects (Number of subjects with AEs/Number of subjects in ITT cohort) .
AEs/Subjects (Min. Max) .
. Days to onset (Min. Max)
Days to Resolution (Min, Max) .
. Visit when AE occurred, Stent placement procedure, Serious (Number of AEs that occurred at that visit/Total number of AEs)

There were four device-related AEs, with onset ranging from 20 days to 56 days after AXIOS stent placement. Three of these device-related AEs were non-serious and resolved without sequelae zero to 6 days after onset. One of the device-related AEs was serious and consisted of septic shock with onset 48 days after AXIOS stent placement, 28 days after AXIOS stent removal, and with fatal outcome one day after onset of septic shock. Details are provided below:

. Right Upper Quadrant Abdominal Pain (Subject 0305G006) - onset: 56 days after AXIOS stent placement; duration: 4 days; outcome: recovered/resolved.
Septic shock (Subject 0859G006) onset: 48 days after AXIOS stent placement; duration: . n/a; outcome: fatal.
. Sepsis (Subject 0859G007) - onset: 20 days after AXIOS stent placement; duration: 6 days; outcome: recovered/resolved.
Mucosal injury /minor bleeding (Subject 0859G009) onset: 35 days after AXIOS stent . placement; duration: 0 days; outcome: recovered/resolved.

Conclusion

The primary effectiveness endpoint consisted of the days to resolution of Acute Cholecystitis. The study hypothesized that this endpoint would be less than 3.5 days. The study observed 1.60±1.50 days to resolution of acute cholecystitis for the 30 ITT patients with 97.8% one-sided confidence interval of [0.0, 2.15], and thus met the study hypothesis. The secondary effectiveness endpoint consisted of rate of reinterventions affecting the biliary tract for reasons other than confirmed malignant biliary stenosis. The study hypothesized that this endpoint would be less than 46.2%. The study observed 16.7% (5/30) of patients with one-sided 99.7% confidence interval of [0.0, 42.0%], and thus met the study hypothesis. There have been no unanticipated adverse events (AEs) reported in this study. There have been one hundred eleven (11) AEs of which thirtv-five (35) were recorded as Serious Adverse Events (SAEs). Only one (1) SAE was reported as related to the AXIOS™ Stent and AXIOS™ Stent placement procedure; this event led to death.

META-ANALYSIS OF CLINICAL LITERATURE

A systematic review and meta-analysis of the literature were conducted to provide an evaluation of available publications reporting on the rates of technical success, clinical success, recurrent cholecystitis, procedure-related adverse events, overall adverse events, and re-intervention in patients with acute cholecystitis who have undergone EUS-guided cholecystostomy with the

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AXIOS stent. Seventeen articles were retained for analysis, encompassing 713 patients, as summarized in Table 5 below. A random-effects model was utilized to account for heterogeneity in the analysis.

Outcome	AXIOS TM Gallbladder Random EffectsModelling
	#Refs	TotalN	Meta-analysis Point Estimate (95%CI)
Technical Success	17	666	97.0% (95.1%, 98.5%)
Clinical Success	15	595	92.0% (89.2%, 94.3%)
Recurrent Cholecystitis	13	551	1.8% (0.4%, 4.2%)
Procedure Related AEs	14	591	12.0% (8.5%, 16.0%)
Overall AEs	16	610	22.7% (17.5%, 28.4%)
Re-interventions	5	257	10.3% (2.6%, 22.1%)

Table 5. Meta-Analysis of Data from Clinical Literature of AXIOS used for Gallbladder Drainage

Notably, the metanalysis included a randomized control trial (Teoh AY, Kitano M, Itoi T, et al. Endosonography-guided gallbladder drainage versus percutaneous cholecystostomy in very high-risk surgical patients with acute cholecystitis: an international randomised multicentre controlled superiority trial (DRAC 1), Clinical Study, Gut, 2020;69(6):1085-1091), which compared endoscopic ultrasound (EUS-GBD) with the AXIOS stent versus percutaneous cholecystectomy (PT-GBD), the standard of care. This is the first prospective, multi-centered randomized controlled trial comparing EUS-GBD with PTGBD. After randomization of 80 patients and exclusion of a patient who developed gallbladder cancer, the analysis included 39 patients in the EUS-GBD group and 40 patients in the PT-GBD group.

The following results were extracted from the literature for usage of LAMS (AXIOS) for management of acute cholecystitis:

Outcome	Study Reported Results(95% Confidence Interval)
Technical Success	97.4%(86.5%, 99.9%)
Clinical Success	92.3 %(79.1%, 98.4%)
Recurrent Cholecystitis	2.6%(0.1%, 13.5%)

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Procedure Related AEs	12.8%(4.3%, 27.4%)
Overall AEs	25.6%(13.0%, 42.1%)
Re-interventions	2.6%(0.1%, 13.5%)

There were no differences in technical success (97.4% vs 100%. p=0.494), clinical success (92.3% vs 92.5%, p=1), or 30-day mortality between EUS-GBD and PT-GBD (3/39 (7.7%) vs 4/40 (10%), p=0.675). Compared to PT-GBD, EUS-GBD significantly reduced 30-day adverse events (12.8% vs 47.5%, p=0.001) and 1-year adverse events (25.6% vs 77.5%, p<0.001).

Pediatric Extrapolation

In this De Novo request, existing clinical data were not leveraged to support the use of the device in a pediatric patient population.

LABELING

Physician labeling includes the device indications for use, a description of the device, warnings and precautions, clinical data on the device, and instructions for the safe and effective use of the device. The labeling satisfies the requirements of 21 CFR 801.109 Prescription devices. Per the Special Controls for this type of device, the labeling includes:

. Instructions for stent deployment, use, and removal
Information on device technical parameters .
A summary of clinical data obtained with the device, including a summary of reported . adverse events and a summary of subject demographics

Other labeling includes an implant card and an information booklet for patients.

RISKS TO HEALTH

The table below identifies the risks to health that may be associated with use of the gallbladder drainage stent and delivery system and the measures necessary to mitigate these risks.

Risks to Health	Mitigation Measures
Procedural complications, leading torecurrent cholecystitisImproper stent placement Improper stent removal Stent obstruction/ingrowth Stent migration/dislodgement	Clinical performance dataNon-clinical performance testingLabeling

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Tissue unable to support stent placement due to:- Lack of gallbladder wall integrity- Lack of gallbladder adherence to bowel wall	Clinical performance dataNon-clinical performance testingLabeling
Infection/sepsis	Sterilization validationLabeling
Adverse tissue reaction	Biocompatibility evaluation
MR incompatibility, leading to tissue damage	Non-clinical performance testing

SPECIAL CONTROLS

In combination with the general controls of the FD&C Act, the gallbladder drainage stent and delivery system is subject to the following special controls:

(1) Clinical performance data must demonstrate that the device performs as intended under its anticipated conditions of use, and capture any adverse events observed during clinical use. Data must describe major clinical outcomes including stent patency, stent placement, and stent removal.
(2) Non-clinical performance testing must demonstrate that the stent and any associated delivery systems perform as intended under anticipated conditions of use. The following performance characteristics must be tested to demonstrate the stent will withstand forces and conditions encountered during use:
- Deployment testing of the stent under simulated use conditions; (i)
- Removal force testing to demonstrate that the stent will remain in place: (ii)
- Compression and expansion force testing; (iii)
- (iv) Dimensional verification testing;
- Tensile testing of joints and materials; (v)
- Fatigue testing to characterize material strength; and (vi)
- (vii) Corrosion testing.
The patient-contacting components of the device must be demonstrated to be (3) biocompatible.
(4) Performance data must demonstrate the sterility of patient-contacting components of the device.
Performance data must support the shelf life of the device by demonstrating continued (5) sterility, package integrity, and device functionality over the requested shelf life.
Performance data must evaluate the compatibility of the stent in a magnetic resonance (6) (MR) environment.

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Labeling must include: (7)
- Specific instructions and the expertise needed for the safe use of the device. (i) including deployment of the device, maintenance of the drainage lumen, and removal of the device:
- (ii) A detailed summary of the clinical data pertinent to use of the device, including device- and procedure-related complications:
- (iii) A detailed summary of the device technical parameters; and
- (iv) An expiration date or shelf life.

BENEFIT-RISK DETERMINATION

The probable risks of the device for this intended use are based on data collected in the clinical study described above. The study identified 111 AEs, 35 of which are denoted as severe adverse events. The study noted that 16.7% of patients required reintervention. These adverse events were not unexpected given the high-risk patient population (i.e., those too ill to undergo cholecystectomy) and were comparable to what is observed for the clinical alternative. percutaneous cholecystostomy.

There were no unanticipated AEs reported in this study. There were 111 AEs of which 35 were recorded as SAEs. Only one SAE was reported as related to the AXIOS Stent and AXIOS Stent placement procedure. This event led to death (see narrative below). There were ten non-serious AEs related to the AXIOS Stent, stent placement procedure and/or stent removal. The device related SAE occurred after successful stent removal, with persistent debris in the gallbladder and loss of plastic stents to maintain drainage. There were 10 re-interventions in 8 patients.

Below is a narrative for the serious AE of 'septic shock' in Subject 0859G006:

The patient's baseline medical history was notable for atrial fibrillation, secondary heart failure with preserved ejection fraction, chronic renal failure KDIGO 4 with a clearance of 17 and acute cholecystitis (calculous, Grade 1). The subject underwent the AXIOS™ stent 0859G006 placement procedure into the gallbladder using a transgastric approach on 23FEB2021. Stone removal was performed. and drainage was visualized through the study stent. It was confirmed on 26FEB2021 that the acute cholecystitis had resolved. The study stent was removed on 23MAR2021, and a mucosal injury was noted (linear ulceration of the greater curvature of the stomach). Stone and food debris removal was also performed from the gallbladder during the AXIOS™ stent removal procedure. A small sessile gallbladder polyp measuring +/-3-4mm was visualized and biopsied. Two (2) Solus plastic double pigtail stents (10 Fr x 5 cm) were placed in the gallbladder through the fistula tract after the AXIOS™ stent removal to prevent recurrence of food rests accumulating in the gallbladder. The patient was hospitalized on 12APR2021 with right hypochondrium pain. Augmentin was started. Abdominal US showed minimally thickened gallbladder wall, trace fluid in the gallbladder bed, and the gallbladder was filled with sludge/ food residue suggestive of cholecystitis. The 2 Solus plastic stents that were placed on 23MAR2021 were not visible. The patient developed shock, hypotension, reduced awareness (GCS 12/15) and required oxygen (up to 5L ). At the time of admission, patient had no fever, a white cell count of 11. 7 x 10*12 and a CRP level of 27.9mg/dL. The CRP rose to 280mg/dL the next day. Subject was considered to be septic in view of clinical presentation and CRP was elevated at 280 mg/L. Patient went into cardiac arrest and thoracic massage was started. After 20 minutes of cardiopulmonary resuscitation, a decision was made to stop the thoracic massage. The

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subject expired on (b)(6) as a result of cardiac arrest and presumed septic shock possibly from recurrent acute cholecystitis.

The Secondary Effectiveness Endpoint of rate of reintervention including migration or occlusion was observed to be 16.7% (5/30) for ITT patients (one-sided 99.7% confidence interval [0.0, 42.0%1).

The probable benefits of the device are also based on data collected in the clinical study and the literature analysis. The clinical study demonstrated that the device could assist in resolving symptoms associated with AC. The clinical study also helped demonstrate proper stent placement and removal. 28 of the 30 natients in the ITT cohort achieved technical success (93.3%), i.e., underwent successful placement of the AXIOS stent with subsequent resolution of cholecystitis within 1.39±0.92 days (one-sided 97.8% CI [0.0, 1.74] days). Two of the 30 patients in the ITT cohort did not receive the AXIOS stent and accordingly underwent alternate treatment for their AC, namely using antibiotics in one patient fresolved at day 1] and percutaneous drainage in the other [resolved at day 8]. However, a potential limitation of this study is the lack of any comparator and the limited sample size (N=28 per protocol patients). In addition, placement of the device requires a skilled interventional endoscopist and the procedure is operator dependent.

In the available clinical literature, a recent randomized clinical trial (Teoh AY, Kitano M, Itoi T, et al. Endosonography-guided gallbladder drainage versus percutaneous cholecystostomy in very high-risk surgical patients with acute cholecystitis: an international randomized multicenter controlled superiority trial (DRAC 1), Clinical Study, Gut. 2020;69(6):1085-1091.) compared gallbladder drainage with the AXIOS stent versus percutaneous cholecystostomy, a standard of care procedure. The study data noted that patients treated with the AXIOS stent experienced fewer 30-day and 1-year adverse events than patients treated with the standard of care. For patients treated with the AXIOS stent, 1 year adverse events were fewer (10 (25.6%) versus 31 (77.5%) p<0.001); as were 30-day adverse events (5 (12.8%) versus 19 (47.5%), p=0.010), reinterventions after 30 days (1/39 (2.6%) versus 12/40 (30%), p=0.001), the number of unplanned readmissions (6/39 (15.4%) versus 20/40 (50%), p=0.002) and recurrent cholecystits (1/39 (2.6%) versus 8/40 (20%), p=0.029). Postprocedural pain scores and analgesic requirements were also less (p=0.034).

The technical success (97.4% versus 100%, p=0.494), clinical success (92.3% versus 92.5%. p=1), and 30-day mortality (7.7% versus 10%, p=1) were statistically similar. This randomized trial with the standard of care comparator provides strong real-world evidence of the performance of the device.

AC is recognized as a morbid condition among patients who cannot undergo curative treatment by surgical cholecystectomy. When compared to other treatment options (e.g., percutaneous cholecystostomy), transluminal drainage is a less invasive procedure with a favorable benefit risk profile outlined by the study above. Clinical success (based on resolution of AC symptom) is likely cofounded by the morbid condition of the patients. Nonetheless, the provided clinical data were able to show a resolution of symptoms for the per protocol patient population. Moreover, the trial data demonstrate technical success, including a proper stent placement, patency, and removal.

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Patient Perspectives

This submission did not include specific information on patient perspectives for this device.

Benefit/Risk Conclusion

In conclusion, given the available information above, for the following indication statement:

The AXIOS Stent and Electrocautery Enhanced Delivery System is indicated for use to facilitate transgastric or transduodenal endoscopic drainage of the gallbladder in patients with acute cholecystitis who are at high risk for surgery.

The probable benefits outweigh the probable risks for the AXIOS Stent and Electrocautery-Enhanced Delivery System (10 mm x 10 mm Stent); AXIOS Stent and Electrocautery-Enhanced Delivery System (15 mm x 10 mm Stent). The device provides benefits, and the risks can be mitigated using general controls and the identified special controls.

CONCLUSION

The De Novo request for the AXIOS Stent and Electrocautery-Enhanced Delivery System (10 mm x 10 mm Stent); AXIOS Stent and Electrocautery-Enhanced Delivery System (15 mm x 10 mm Stent) is granted and the device is classified under the following:

Product Code: OXH Device Type: Gallbladder drainage stent and delivery system Regulation Number: 21 CFR 876.5016 Class: II

Regulation Number and Section

N/A

Acceptance Criteria and Device Performance

1. Table of Acceptance Criteria and Reported Device Performance

2. Sample Sizes Used for the Test Set and Data Provenance

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications

4. Adjudication Method for the Test Set

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study

7. The Type of Ground Truth Used

8. The Sample Size for the Training Set

9. How the Ground Truth for the Training Set Was Established

DE NOVO CLASSIFICATION REQUEST FOR AXIOS STENT AND ELECTROCAUTERY-ENHANCED DELIVERY SYSTEM (10 MM X 10 MM STENT); AXIOS STENT AND ELECTROCAUTERY-ENHANCED DELIVERY SYSTEM (15 MM X 10 MM STENT)

REGULATORY INFORMATION

BACKGROUND

SPONSOR INFORMATION:

INDICATIONS FOR USE

LIMITATIONS

DEVICE DESCRIPTION

SUMMARY OF NONCLINICAL/BENCH STUDIES

BIOCOMPATIBILITY/MATERIALS

SHELF LIFE/STERILITY

SUMMARY OF CLINICAL INFORMATION

PIVOTAL STUDY DATA

Primary Effectiveness Endpoints

Additional Endpoints

Table 1: Resolution of Acute Cholecystitis (AC)

Secondary Effectiveness Endpoint - Rate of re-interventions:

Additional Endpoints

Adverse Events

Table 4. Summary of Adverse Events

AEs/Subjects (Min. Max) .

Conclusion

META-ANALYSIS OF CLINICAL LITERATURE

Pediatric Extrapolation

LABELING

RISKS TO HEALTH

SPECIAL CONTROLS

BENEFIT-RISK DETERMINATION

Patient Perspectives

Benefit/Risk Conclusion

CONCLUSION