VITEK 2 STRPTOCOCCUS AMPICILLIN

K112075 · bioMerieux, Inc. · LON · Sep 15, 2011 · Microbiology

Device Facts

• Record ID: K112075
• Device Name: VITEK 2 STRPTOCOCCUS AMPICILLIN
• Applicant: bioMerieux, Inc.
• Product Code: LON · Microbiology
• Decision Date: Sep 15, 2011
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 866.1645
• Device Class: Class 2

Indications for Use

VITEK® 2 Streptococcus Ampicillin is designed for antimicrobial susceptibility testing of Streptococcus species. VITEK® 2 Streptococcus Ampicillin is a quantitative test intended for use with the VITEK® 2 and the VITEK® 2 Compact Systems as a laboratory aid in the determination of in vitro susceptibility to antimicrobial agents. Ampicillin has been shown to be activity against the microorganisms listed below: - Beta-hemolytic group Streptococcus species - Viridans group Streptococcus species The VITEK® 2 Antimicrobial Susceptibility Test (AST) is intended to be used with the VITEK® 2 System for the automated quantitative or qualitative susceptibility testing of isolated colonies for the most clinically significant aerobic gram-negative bacilli, Staphylococcus spp., Enterococcus spp., Streptococcus spp. and clinically significant yeast.

Device Story

VITEK® 2 AST-ST Ampicillin is a miniaturized, automated antimicrobial susceptibility test (AST) card used with VITEK® 2 and VITEK® 2 Compact systems. Bacterial isolates are diluted in saline, used to rehydrate antimicrobial medium in the card, and processed by the system. The VITEK® 2 system automatically fills, seals, and incubates the card, monitoring growth in each well over time. The VITEK® 2 Compact utilizes manual filling and sealing. The system generates a report providing the Minimum Inhibitory Concentration (MIC) and interpretive category results. Used in clinical laboratories by technicians to assist healthcare providers in selecting appropriate antimicrobial therapy for Streptococcus infections.

Clinical Evidence

Performance evaluated via clinical and challenge studies (n=1272 combined). Compared to CLSI broth microdilution reference method. Results: 99.1% Essential Agreement (EA) and 97.0% Category Agreement (CA). Minor discrepancies observed; no major or very major discrepancies. Reproducibility >95%. Bench testing only.

Technological Characteristics

Miniaturized AST card utilizing doubling dilution methodology. Automated incubation and optical growth monitoring. Compatible with VITEK® 2 and VITEK® 2 Compact instrument platforms. Quantitative MIC determination.

Indications for Use

Indicated for antimicrobial susceptibility testing of isolated colonies of Beta-hemolytic group Streptococcus species and Viridans group Streptococcus species to determine in vitro susceptibility to Ampicillin.

Regulatory Classification

Identification

A fully automated short-term incubation cycle antimicrobial susceptibility system is a device that incorporates concentrations of antimicrobial agents into a system for the purpose of determining in vitro susceptibility of bacterial pathogens isolated from clinical specimens. Test results obtained from short-term (less than 16 hours) incubation are used to determine the antimicrobial agent of choice to treat bacterial diseases.

Special Controls

*Classification.* Class II (special controls). The special control for this device is FDA's guidance document entitled “Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA.”

Predicate Devices

• VITEK® 2 Gram Positive Amoxicillin for Streptococcus pneumoniae (k063597)

Submission Summary (Full Text)

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# 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY ASSAY ONLY TEMPLATE

A. 510(k) Number:
k112075

B. Purpose for Submission:
The addition of Ampicillin to the VITEK® 2 and VITEK®2 Compact Systems Antimicrobial Susceptibility Test (AST) Systems

C. Measurand
Ampicillin concentrations 0.5, 1, 4 and 8 µg/mL (the MIC range is ≤ 0.25- ≥ 16 µg/mL)

D. Type of Test:
Quantitative growth based detection algorithm using optics light detection

E. Applicant:
bioMérieux, Inc.

F. Proprietary and Established Names:
Vitek®2 Streptococcus Ampicillin (≤ 0.25- ≥ 16 µg/mL)

G. Regulatory Information:
1. Regulation section:
866.1645 Short-Term Antimicrobial Susceptibility Test System
2. Classification:
II
3. Product Code:
LON System, Test, Automated, Antimicrobial Susceptibility, Short Incubation

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4. Panel:
83 Microbiology

H. Intended Use:

1. Intended use(s):

VITEK® 2 Streptococcus Ampicillin is designed for antimicrobial susceptibility testing of Streptococcus species. VITEK® 2 Streptococcus Ampicillin is a quantitative test intended for use with the VITEK® 2 and the VITEK® 2 Compact Systems as a laboratory aid in the determination of in vitro susceptibility to antimicrobial agents. Ampicillin has been shown to be activity against the microorganisms listed below:
- Beta-hemolytic group Streptococcus species
- Viridans group Streptococcus species

The VITEK® 2 Antimicrobial Susceptibility Test (AST) is intended to be used with the VITEK® 2 System for the automated quantitative or qualitative susceptibility testing of isolated colonies for the most clinically significant aerobic gram-negative bacilli, Staphylococcus spp., Enterococcus spp., Streptococcus spp. and clinically significant yeast.

2. Indication(s) for use:

VITEK® 2 Streptococcus Ampicillin is designed for antimicrobial susceptibility testing of Streptococcus species. VITEK® 2 Streptococcus Ampicillin is a quantitative test intended for use with the VITEK® 2 and the VITEK® 2 Compact Systems as a laboratory aid in the determination of in vitro susceptibility to antimicrobial agents. Ampicillin has been shown to be activity against the microorganisms listed below:
- Beta-hemolytic group Streptococcus species
- Viridans group Streptococcus species

The VITEK® 2 Antimicrobial Susceptibility Test (AST) is intended to be used with the VITEK® 2 System for the automated quantitative or qualitative susceptibility testing of isolated colonies for the most clinically significant aerobic gram-negative bacilli, Staphylococcus spp., Enterococcus spp., Streptococcus spp. and clinically significant yeast.

3. Special condition for use statement(s):

Prescription Use Only

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4. Special instrument Requirements:

VITEK® 2 and the VITEK® 2 Compact Systems

I. Device Description:

Each VITEK® 2 test card contains 64 micro-wells. A control well which contains only microbiological culture media is resident on all cards. The remaining wells contain premeasured portions of a specific antibiotic combined with culture media. The bacterial or yeast isolate to be tested is diluted to a standardized concentration with 0.45 – 0.5% saline before being used to rehydrate the antimicrobial medium within the card. The VITEK 2 System automatically fills, seals and places the card into the incubator/reader. The VITEK 2 Compact has a manual filling, sealing and loading operation. The VITEK 2 Systems monitor the growth of each well in the card over a defined period of time. At the completion of the incubation cycle, a report is generated that contains the MIC value along with the interpretive category result for each antibiotic contained on the card.

The VITEK 2 AST-ST Ampicillin has the following concentrations in the card: 0.5, 1, 4 and 8μg/mL (equivalent standard method concentration by efficacy in μg/mL). The MIC result range for the VITEK 2 card is ≤0.25 – ≥ 16μg/mL.

J. Substantial Equivalence Information:

1. Predicate device name(s)

VITEK® 2 Gram Positive Amoxicillin for Streptococcus pneumoniae

2. Predicate K number(s):

k063597

3. Comparison with predicate

| Similarities | | |
| --- | --- | --- |
| Item | Device | Predicate |
| Intended Use | Determine antimicrobial susceptibility to antimicrobial agents | Same |
| Test Card | VITEK® 2 card format with base broth | same |
| Instrument | VITEK® 2 and VITEK® 2 Compact System | same |

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| Differences | | |
| --- | --- | --- |
| Item | Device | Predicate |
| Antibiotic | Ampicillin | Amoxicillin |
| Reading algorithm | Unique for Ampicillin | Unique for amoxicillin |
| Test organism | Beta-hemolytic group Streptococcus species Viridans group Streptococcus species | S. pneumoniae |

# K. Standard/Guidance Document Referenced (if applicable):

Class II Special Controls Guidance Document: "Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA"

CLSI M7-A8 "Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically; Approved Standard"

CLSI M100-S19 "Performance Standards for Antimicrobial Susceptibility; Twenty-First Information Supplement"

# L. Test Principle:

Each VITEK® 2 test card contains 64 micro-wells. A control well which contains only microbiological culture media is resident on all cards. The remaining wells contain premeasured portions of a specific antibiotic combined with culture media. The bacterial or yeast isolate to be tested is diluted to a standardized concentration with $0.45 - 0.5\%$ saline before being used to rehydrate the antimicrobial medium within the card. The VITEK 2 System automatically fills, seals and places the card into the incubator/reader. The VITEK 2 Compact has a manual filling, sealing and loading operation. The VITEK 2 Systems monitor the growth of each well in the card over a defined period of time. At the completion of the incubation cycle, a report is generated that contains the MIC value along with the interpretive category result for each antibiotic contained on the card.

The VITEK 2 AST-ST Ampicillin has the following concentrations in the card:, 0.5, 1, 4, and $8\mu \mathrm{g / mL}$ (equivalent standard method concentration by efficacy in $\mu \mathrm{g / mL}$ ). The MIC result range for the VITEK 2 card is $\leq 0.25 - \geq 16\mu \mathrm{g / mL}$ .

In addition to the automatic dilution, there is also a manual inoculation dilution procedure described in the package insert.

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M. Performance Characteristics (if/when applicable):

1. Analytical performance:

a. Precision/Reproducibility:

Reproducibility was demonstrated using 10 isolates at 3 sites on 3 separate days in triplicates. The study included the Auto-dilution and the Manual dilution with the VITEK®2, and the Manual dilution with the VITEK®2 Compact. All results were >95% reproducible.

b. Linearity/assay reportable range:

Not Applicable

c. Traceability (controls, calibrators, or method):

The recommended QC isolates were tested on every test occasion with the reference method and the VITEK®2. The reference method QC results were in range for every day tested. The VITEK®2 was tested a sufficient number of times to demonstrate that the system can produce QC results in the recommended range.

Quality Control was performed during the studies using both the auto-dilution and the manual method of diluting the organisms. Results demonstrated that methods were comparable with the same mode.

Quality Control Summary (VITEK®2, Auto and Manual dilution)

| Organism | Conc in μg/ml | Auto-dilution | | Manual dilution | |
| --- | --- | --- | --- | --- | --- |
| S. pneumoniae
ATCC 49619
Expected Range
0.06- 0.25 μg/ml | | Ref. | Test | Ref. | Test |
| | ≤0.03 | 2 | | 2 | |
| | 0.06 | 114 | | 111 | |
| | 0.12 | 66 | | 66 | |
| | 0.25 | | 182 | | 179 |
| | | | | | |

An additional QC study was performed with the VITEK®2 Compact, the secondary option, at three sites, with the following results.

Quality Control Summary (VITEK®2 Compact, Manual dilution)

| Organism | Conc in μg/ml | Manual-dilution | |
| --- | --- | --- | --- |
| S. pneumoniae
ATCC 49619
Expected Range
0.06- 0.25 μg/ml | | Ref. | Test |
| | ≤0.03 | | |
| | 0.06 | 61 | |
| | 0.12 | 13 | |
| | 0.25 | | 74 |
| | | | |

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Inoculum density control was monitored using the DensiChek2 instrument. This was standardized weekly with all results recorded and in the expected range. Verification was performed during internal testing.

d. Detection limit:

Not Applicable

e. Analytical specificity:

Not Applicable

f. Assay cut-off:

Not Applicable

## 2. Comparison studies:

The reference method follows CLSI approved broth microdilution testing conditions:

- Medium: Mueller-Hinton broth supplemented with lysed blood
- Inoculum: Direct colony suspension
- Incubation: 35°C, ambient air, 20-24 hours

a. Method comparison with predicate device:

Clinical study was performed at four external sites using the VITEK2 Streptococcus Ampicillin and broth microdilution panels containing Ampicillin. A total of 1124 clinical isolates were tested at four external sites by auto inoculation. The no growth rate was 0.8% (9/1124) in the VITEK®2 AST-ST Ampicillin Test. Three hundred and eight (27.4%: 308/1124) were from stock isolates.

Performance Summary Table (VITEK 2, Auto Dilution)

| | total | EA | %EA | Eval EA Total | Eval EA | Eval %EA | CA | %CA | #R | min | maj | vmj |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Clinical | 1115 | 1104 | 99.0 | 60 | 54 | 90.0 | 1078 | 96.7 | 14 | 37 | 0 | 0 |
| Challenge | 157 | 157 | 100 | 6 | 6 | 100 | 156 | 99.4 | 10 | 1 | 0 | 0 |
| Combined | 1272 | 1261 | 99.1 | 66 | 60 | 90.9 | 1234 | 97.0 | 24 | 38 | 0 | 0 |

EA-Essential Agreement
CA-Category Agreement
R-resistant isolates

maj-major discrepancies
vmj-very major discrepancies
min-minor discrepancies

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Manual Dilution:

The challenge set of 157 organisms was also tested at one site using the manual method of inoculation for VITEK2 and VITEK2 Compact with the following performance.

Comparison Challenge Data - VITEK 2, and VITEK2 Compact (Manual dilution)

| | total | EA | %EA | Eval EA Total | Eval EA | Eval %EA | CA | %CA | #R | min | maj | vmj |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| VITEK2 | 157 | 156 | 99.4 | 6 | 6 | 100 | 156 | 99.4 | 10 | 1 | 0 | 0 |
| VITEK2 Compact | 157 | 155 | 98.7 | 6 | 6 | 100 | 155 | 98.7 | 10 | 2 | 0 | 0 |

The performance of the optional VITEK®2 Compact was evaluated in the QC, challenge, and reproducibility studies.

b. Matrix comparison:

Not Applicable

3. Clinical studies:

a. Clinical sensitivity:

Not Applicable

b. Clinical specificity:

Not Applicable

c. Other clinical supportive data (when a and b are not applicable):

4. Clinical cut-off:

Not Applicable

5. Expected values/Reference range

Beta Streptococcus ≤ 0.25 (S), 0.5- ≥ 16 (NS)

Viridans Group Streptococcus ≤ 0.25 (S), 0.5- 4(I), 8 - ≥16(R)

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N. Proposed Labeling:

The labeling is sufficient and satisfies the requirement of 21 CFR Part 809.10.

O. Conclusion:

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

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