HardyDisk AST Sulbactam/Durlobactam 10/10µg (SUD20)

K231568 · Hardy Diagnostics · JTN · Jul 6, 2023 · Microbiology

Device Facts

• Record ID: K231568
• Device Name: HardyDisk AST Sulbactam/Durlobactam 10/10µg (SUD20)
• Applicant: Hardy Diagnostics
• Product Code: JTN · Microbiology
• Decision Date: Jul 6, 2023
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 866.1620
• Device Class: Class 2

Indications for Use

HardyDisk™ AST Disks are used for semi-quantitative in vitro susceptibility testing by the agar diffision test procedure (Kirby-Bauer) of rapidly growing and certain fastidious bacterial pathogens. Standardized methods for agar diffusion testing have been described for Enterobacterales, Staphylococcus spp., Acinetobacter spp., Listeria monocytogenes, Enterococcus spp., and by modified procedures, Candidas spp., Neisseria gonorrhoeae, Neisseria meningitidis and Streptococcus spp., including Streptococcus pneumoniae. Use of HardyDisk™ AST Sulbactam 10/10ug (SUD20) for in vitro agar diffusion susceptibility testing is indicated when there is the need to determine the susceptibility of microorganisms to Sulbactam. HardyDisk™ AST Sulbactam/Durlobactam at concentration 10/10ug can be used to determine the zone diameter (mm) of Sulbactam/Durlobactam against the following microorganisms for which Sulbactam has been shown to be active both clinically and in vitro: Acinetobacter baumannii-calcoaceticus complex (ABC).

Device Story

HardyDisk AST Sulbactam/Durlobactam 10/10μg (SUD20) consists of 6mm white filter paper disks impregnated with 10μg Sulbactam and 10μg Durlobactam. Used in clinical microbiology laboratories for in vitro antimicrobial susceptibility testing (AST) via Kirby-Bauer agar diffusion. Procedure involves inoculating Mueller Hinton agar with bacterial isolates (standardized to 0.5 McFarland turbidity), placing disks on the agar surface, and incubating at 35±2°C for 16-18 hours. Healthcare providers measure the resulting zone of inhibition (mm) and compare against FDA-recognized interpretive criteria to categorize the organism as susceptible, intermediate, or resistant. This information assists clinicians in selecting appropriate antimicrobial therapy for patients with infections caused by Acinetobacter baumannii-calcoaceticus complex.

Clinical Evidence

No clinical data. Evidence based on microbiology disk studies evaluated by CDER to establish breakpoints and quality control ranges, supported by stability, disk content optimization, and disk-to-MIC correlation studies.

Technological Characteristics

The device consists of paper disks impregnated with 10/10µg of Sulbactam/Durlobactam. It operates via the Kirby-Bauer agar diffusion principle, where the antibiotic diffuses into an agar medium to inhibit bacterial growth. It is a standalone, non-electronic, manual diagnostic tool used in laboratory settings.

Indications for Use

Indicated for semi-quantitative in vitro susceptibility testing of Acinetobacter baumannii-calcoaceticus complex (ABC) to Sulbactam/Durlobactam using the Kirby-Bauer agar diffusion method.

Regulatory Classification

Identification

An antimicrobial susceptibility test disc is a device that consists of antimicrobic-impregnated paper discs used to measure by a disc-agar diffusion technique or a disc-broth elution technique the in vitro susceptibility of most clinically important bacterial pathogens to antimicrobial agents. In the disc-agar diffusion technique, bacterial susceptibility is ascertained by directly measuring the magnitude of a zone of bacterial inhibition around the disc on an agar surface. The disc-broth elution technique is associated with an automated rapid susceptibility test system and employs a fluid medium in which susceptibility is ascertained by photometrically measuring changes in bacterial growth resulting when antimicrobial material is eluted from the disc into the fluid medium. Test results are used to determine the antimicrobial agent of choice in the treatment of bacterial diseases.

Submission Summary (Full Text)

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FDA

U.S. FOOD & DRUG

ADMINISTRATION

# 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY

ASSAY ONLY

## I Background Information:

A 510(k) Number

K231568

B Applicant

Hardy Diagnostics

C Proprietary and Established Names

HardyDisk AST Sulbactam/Durlobactam 10/10μg (SUD20)

D Regulatory Information

| Product Code(s) | Classification | Regulation Section | Panel |
| --- | --- | --- | --- |
| JTN | Class II | 21 CFR 866.1620 - Antimicrobial Susceptibility Test Disc | MI - Microbiology |

## II Submission/Device Overview:

A Purpose for Submission:

To obtain a substantial equivalence determination for Sulbactam/Durlobactam Antimicrobial Susceptibility Test Disk

B Measurand:

Sulbactam/Durlobactam 10/10μg

C Type of Test:

Antimicrobial Susceptibility Test Disks

## III Intended Use/Indications for Use:

Food and Drug Administration

10903 New Hampshire Avenue

Silver Spring, MD 20993-0002

www.fda.gov

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# A Intended Use(s):

HardyDisk AST Disks are used for semi-quantitative *in vitro* susceptibility testing by the agar diffusion test procedure (Kirby-Bauer) of rapidly growing and certain fastidious bacterial pathogens. Standardized methods for agar diffusion testing have been described for Enterobacterales, *Staphylococcus* spp., *Pseudomonas* spp., *Acinetobacter* spp., *Listeria monocytogenes*, *Enterococcus* spp., and by modified procedures, *Candida* spp., *Haemophilus* spp., *Neisseria gonorrhoeae*, *Neisseria meningitidis* and *Streptococcus* spp., including *Streptococcus pneumoniae*.

# B Indication(s) for Use:

HardyDisk AST Disks are used for semi-quantitative *in vitro* susceptibility testing by the agar diffusion test procedure (Kirby-Bauer) of rapidly growing and certain fastidious bacterial pathogens. Standardized methods for agar diffusion testing have been described for Enterobacterales, *Staphylococcus* spp., *Pseudomonas* spp., *Acinetobacter* spp., *Listeria monocytogenes*, *Enterococcus* spp., and by modified procedures, *Candida* spp., *Haemophilus* spp., *Neisseria gonorrhoeae*, *Neisseria meningitidis* and *Streptococcus* spp., including *Streptococcus pneumoniae*.

Use of HardyDisk AST Sulbactam/Durlobactam 10/10μg (SUD20) for *in vitro* agar diffusion susceptibility testing is indicated when there is the need to determine the susceptibility of microorganisms to Sulbactam/Durlobactam.

HardyDisk AST Sulbactam/Durlobactam at concentration 10/10μg can be used to determine the zone diameter (mm) of Sulbactam/Durlobactam against the following microorganisms for which Sulbactam/Durlobactam has been shown to be active both clinically and *in vitro*: *Acinetobacter baumannii*-*calcoaceticus* complex (ABC).

# C Special Conditions for Use Statement(s):

Rx - For Prescription Use Only

# D Special Instrument Requirements:

Not applicable.

# IV Device/System Characteristics:

# A Device Description:

HardyDisk AST Sulbactam/Durlobactam 10/10μg (SUD20) is a high quality 6mm diameter white filter paper disk that is impregnated with 10μg Sulbactam and 10μg Durlobactam. The disks are clearly marked on both sides with SUD20, designating the agent and the drug content. The disks are supplied in plastic cartridges containing 50 disks each. HardyDisk AST Sulbactam/Durlobactam 10/10μg (SUD20) is intended to be used for *in vitro* agar diffusion susceptibility testing.

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## B Principle of Operation:

The HardyDisk AST Disk is based on the agar diffusion (Kirby-Bauer) methodology. It utilizes dried filter paper disks impregnated with a known concentration of an antimicrobial agent that are placed onto the test medium surface. Three to five similar colonies are transferred to 4-5 mL of a suitable broth medium. The broth is incubated at 35°C for 2-6 hours to develop a turbidity that exceeds or is equivalent to a 0.5 McFarland standard. Alternatively, a direct broth or saline suspension of colonies may be prepared from an overnight culture. The final inoculum density should be equivalent to a 0.5 McFarland turbidity standard. The inoculum density may also be standardized photometrically.

Within 15 minutes of inoculum preparation, the Mueller Hinton agar plate is streaked with an inoculated swab to obtain an even inoculation of organism. Disks are aseptically placed onto the agar surface with a disk dispenser and the disks are pressed down with a sterile needle or forceps to make contact with the agar surface. Agar plates are incubated in an ambient air incubator at 35±2°C for 16-18 hours.

After incubation, the agar medium is examined for a zone of inhibition around the disks. The zones of inhibition are measured to the nearest millimeter and compared to recognized zone size ranges for the antimicrobial agent being tested.

## V Substantial Equivalence Information:

### A Predicate Device Name(s):

Hardy Disk Ast Tigecycline 15μg

### B Predicate 510(k) Number(s):

K062245

### C Comparison with Predicate(s):

| Device & Predicate Device(s): | Device: K231568 | Predicate: K062245 |
| --- | --- | --- |
| Device Trade Name | HardyDisk AST Sulbactam/Durlobactam 10/10μg (SUD20) | Hardy Disk Ast Tigecycline 15μg |
| General Device Characteristic Similarities | | |
| Intended Use/Indications For Use | Antimicrobial Susceptibility Test Disks are used for in vitro susceptibility testing by standardized agar diffusion test procedures. | Same |

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| Test Method | Antimicrobial Susceptibility testing using paper disks impregnated with an antimicrobial agent | Same |
| --- | --- | --- |
| Methodology | Kirby-Bauer Disk Diffusion Susceptibility Test Protocol require the user to determine categorical interpretations (S/I/R) using the measured zone diameters. | Same |
| Inoculum | Prepared from pure isolated colonies to match the turbidity equivalent of a 0.5 McFarland in Tryptic Soy Broth. | Same |
| Inoculum Method | Dip a sterile swab into the prepared inoculums, and streak an appropriate agar plate’s surface three times. Add the disks impregnated with the antimicrobial agent to the surface of the plate. The temperature, atmospheric conditions and duration of incubation are dependent on the organism tested. | Same |
| Reading Method | The user will interpret the zone diameters according to established interpretive criteria for the drug. | Same |
| General Device Characteristic Differences | | |
| Product Name | HardyDisk AST Sulbactam/Durlobactam 10/10μg (SUD20) | Hardy Disk Ast Tigecycline 15μg |
| Antibiotic | Sulbactam/Durlobactam | Tigecycline |
| Concentration | 10/10μg | 15μg |

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VI Standards/Guidance Documents Referenced:

- CLSI M02-13th ed. Performance Standards for Antimicrobial Disk Susceptibility Tests (January 2018)
- CLSI M100-33rd ed. Performance Standards for Antimicrobial Susceptibility Testing (March 2023).

VII Performance Characteristics (if/when applicable):

The premarket submission for HardyDisk Sulbactam/Durlobactam included a letter dated November 19, 2022 indicating the right of reference to NDA 216974. Descriptive characteristics were sufficient for the HardyDisk Sulbactam/Durlobactam 10/10μg (SUD20) disk based on data from microbiology disk studies evaluated by CDER which were used to generate the breakpoints identified by FDA on the susceptibility test interpretive criteria webpage. In addition, CDER concurred with the disk QC ranges that were established by CLSI. The disk data used to support this submission included data from testing organisms shown to be active in vitro and in clinical infections within the spectrum of activity of Sulbactam/Durlobactam and as noted in the device’s intended use.

Data obtained from stability, quality control, disk to MIC correlation, reproducibility (from disk content optimization) studies were generated in accordance with the CDER Clinical/Antimicrobial guidance, Microbiology Data for Systemic Antibacterial Drugs-Development, Analysis, and Presentation to ensure precise, accurate, and reproducible results.

For this review, the interpretive criteria are applied to Acinetobacter baumannii-calcoaceticus complex (ABC) according to the FDA STIC website. As required under 511A(2)(2)(B) of the Federal Food, Drug and Cosmetic Act, the following statement is included in the Precautions section of the HardyDisk AST Sulbactam/Durlobactam 10/10μg package insert:

Per the FDA-Recognized Susceptibility Test Interpretive Criteria website, the safety and efficacy of antimicrobial drugs, for which antimicrobial susceptibility is tested by this AST device, may or may not have been established in adequate and well-controlled clinical trials for treating clinical infections due to microorganisms outside of those found in the indications and usage in the drug label. The clinical significance of susceptibility information in those instances is unknown. The approved labeling for specific antimicrobial drugs provides the uses for which the antimicrobial drug is approved.

A Analytical Performance:

1. Precision/Reproducibility:
N/A

2. Linearity:
N/A

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3. Analytical Specificity/Interference:
N/A

4. Assay Reportable Range:
N/A

5. Traceability, Stability, Expected Values (Controls, Calibrators, or Methods):
N/A

6. Detection Limit:
N/A

7. Assay Cut-Off:
N/A

## B Comparison Studies:

1. Method Comparison with Predicate Device:
N/A

2. Matrix Comparison:
N/A

## C Clinical Studies:

1. Clinical Sensitivity:
N/A

2. Clinical Specificity:
N/A

3. Other Clinical Supportive Data (When 1. and 2. Are Not Applicable):
N/A

## D Clinical Cut-Off:
N/A

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E Expected Values/Reference Range:

The FDA-identified susceptibility interpretive criteria for Sulbactam/Durlobactam are listed below.

FDA-Identified Disk Diffusion Interpretive Criteria (zone diameter in mm) for Sulbactam/Durlobactam

| Organisms | Susceptible | Intermediate | Resistant |
| --- | --- | --- | --- |
| Acinetobacter-baumannii calcoaceticus complex | ≥ 17 | 14 – 16 | ≤ 13 |

VIII Proposed Labeling:

The labeling supports the finding of substantial equivalence for this device.

IX Conclusion:

The submitted information in this premarket notification is complete and supports a substantial equivalence decision.