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 VITEK® 2 Compact Systems as a laboratory aid in the determination of in vitro susceptibility to antimicrobial agents. Ampicillin has been shown to be active 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 Description

VITEK® 2 AST-ST Ampicillin is designed for antimicrobial susceptibility testing of Streptococcus species. VITEK® 2 AST-ST Ampicillin is a quantitative test intended for use with the VITEK® 2 and VITEK® 2 Compact Systems as a laboratory aid in the determination of in vitro susceptibility to antimicrobial agents. The antimicrobial agent presented in VITEK® 2 AST Cards is in concentrations equivalent by efficacy to standard method concentrations in mcg/ml. The VITEK® 2 AST Cards are essentially miniaturized versions of the doubling dilution technique for determining the minimum inhibitory concentration (MIC) microdilution methodology. The bacterial isolate to be tested is diluted to a standardized concentration in 0.45 - 0.50% 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 and sealing operation. The VITEK® 2 monitors the growth of each well in the card over a defined period of time (up to 36 hours for yeast). At the completion of the incubation cycle, a report is generated that contains the MIC value along with the interpretive category result for each antimicrobial contained on the card.

AI/ML Overview

Here's a breakdown of the acceptance criteria and study details for the VITEK® 2 AST-ST Ampicillin, based on the provided 510(k) summary:

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria for Antimicrobial Susceptibility Test (AST) systems are typically defined in FDA guidance documents. While the exact numerical criteria aren't explicitly stated as a table in this document, the summary refers to "acceptable performance" and the "FDA Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA. Issued August. 28, 2009."

Based on the reported performance, we can infer the acceptance criteria for Essential Agreement (EA) and Category Agreement (CA).

Performance Metric	Acceptance Criteria (Inferred)	Reported Device Performance
Overall Essential Agreement	Likely ≥ 90% (Common AST criteria)	99.1%
Overall Category Agreement	Likely ≥ 90% (Common AST criteria)	97.0%
Reproducibility	Acceptable	Acceptable
Quality Control	Acceptable	Acceptable

Note: The specific numerical acceptance criteria (e.g., "not less than 90%") for Essential and Category Agreement according to the referenced FDA guidance are not explicitly stated in this document but are standard for AST devices.

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

Test Set Description: The external evaluation was conducted with:
- Fresh clinical isolates
- Stock clinical isolates
- A set of challenge strains
Sample Size: The document does not explicitly state the total number of isolates (sample size) used in the external evaluation (test set).
Data Provenance: The document does not explicitly state the country of origin of the data. It mentions an "external evaluation," which typically implies data collected from multiple sites beyond the manufacturer's internal labs. The study was conducted using both fresh and stock clinical isolates, implying a retrospective and prospective mix, as stock isolates are typically retrospective, while fresh isolates would be prospective.

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

The ground truth was established by comparing the device's performance to the CLSI broth microdilution reference method.
This is a laboratory-based reference method, not typically established by individual "experts" in the sense of physicians or radiologists. Rather, it's a standardized laboratory procedure performed by trained microbiologists following CLSI guidelines. Therefore, the concept of "number of experts" with specific clinical qualifications for establishing this kind of ground truth is not directly applicable.

4. Adjudication Method for the Test Set

Since the ground truth is the CLSI broth microdilution reference method, an "adjudication method" involving experts for discrepancies is generally not applicable in the same way it would be for image-based diagnostics where human interpretation is the primary ground truth. The comparison is between the device's MIC/interpretive category and the reference method's MIC/interpretive category. Discrepancies would be analyzed against the standard, but not typically "adjudicated" by multiple rounds of human expert review.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done

No, an MRMC comparative effectiveness study was not done. This type of study investigates the impact of an AI system on human reader performance, which is relevant for diagnostic imaging or clinical decision support tools. This device is an automated laboratory instrument measuring antimicrobial susceptibility, where the comparison is against an established reference method, not against human interpretation of the same data.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done

Yes, a standalone performance evaluation was done. The VITEK® 2 AST-ST Ampicillin device (an automated laboratory instrument) was compared directly to the CLSI broth microdilution reference method. This is a standalone performance evaluation of the device itself, without a human "in-the-loop" for interpreting the results, other than monitoring the instrument and interpreting its final output (MIC and interpretive category). The VITEK 2 system automatically fills, seals, and places the card, and monitors growth, generating an MIC value and interpretive category result.

7. The Type of Ground Truth Used

The ground truth used was the CLSI broth microdilution reference method. This is an industry-standard, well-established laboratory method for determining minimum inhibitory concentrations (MICs) of antimicrobial agents.

8. The Sample Size for the Training Set

The document does not provide information on the sample size used for the training set. It describes the "external evaluation" as the test set for substantial equivalence. For a device like this, the "training" (if an AI/machine learning component were involved) would likely involve a large historical dataset of MIC values used to develop and refine the algorithms for interpreting growth patterns into MICs. This detail is not present in the 510(k) summary.

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

As the document does not specify a training set or its sample size, it does not describe how the ground truth for any potential training set was established. Similar to the test set, any ground truth used during the development or "training" phase would almost certainly have been derived from the CLSI broth microdilution reference method or similar gold standard laboratory methods.

Summary

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K112075

SEP 1 5 2011

510(k) SUMMARY

VITEK® 2 AST-ST Ampicillin

510(k) Submission Information:

Contact Person:

Fax Number:

Submitter's Name:	bioMérieux, Inc.
Address:	595 Anglum RoadHazelwood, MO 63042

Jolyn Tenllado Director, Regulatory Affairs

Phone Number:

314 -731-8386

314-731-8689

September 2011

B. Device Name:

Formal/Trade Name: Classification Name:

Date of Preparation:

VITEK® 2 Streptococcus Ampicillin

VITEK® 2 AST-ST Ampicillin

Fully Automated Short-Term Incubation Cycle Antimicrobial Susceptibility Device, 21 CFR 866.1645 Product Code LON

Common Name:

C. Predicate Device:

VITEK® 2 Gram Positive Amoxicillin for Streptococcus pneumoniae (K063597)

D. 510(k) Summary:

Viridans group Streptococcus species

The antimicrobial agent presented in VITEK® 2 AST Cards is in concentrations equivalent by efficacy to standard method concentrations in mcg/ml. The VITEK® 2 AST Cards are essentially miniaturized versions of the doubling dilution technique for determining the minimum inhibitory concentration (MIC) microdilution methodology.

00/638-4835 Fax: 314/731-8700

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The bacterial isolate to be tested is diluted to a standardized concentration in 0.45 - 0.50% 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 and sealing operation. The VITEK® 2 monitors the growth of each well in the card over a defined period of time (up to 36 hours for yeast). At the completion of the incubation cycle, a report is generated that contains the MIC value along with the interpretive category result for each antimicrobial contained on the card.

VITEK® 2 AST-ST Ampicillin demonstrated substantially equivalent performance when compared with the CLSI broth microdilution reference method, as defined in the FDA Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA. Issued August. 28, 2009.

The Premarket Notification (510[k]) presents data in support of VITEK® 2 AST-ST Ampicillin. An external evaluation was conducted with fresh and stock clinical isolates, as well as a set of challenge strains. The external evaluations were designed to confirm the acceptability of VITEK® 2 AST-ST Ampicillin by comparing its performance with the CLSI broth microdilution reference method. The data is representative of performance on both the VITEK® 2 and VITEK® 2 Compact instrument platforms. VITEK 2 AST-ST Ampicillin demonstrated acceptable performance of 99.1% overall essential agreement and 97.0% overall category agreement with the reference method. Reproducibility and Quality Control demonstrated acceptable results using both the VITEK® 2 and VITEK® 2 Compact instrument systems.

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Image /page/2/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a stylized depiction of an eagle or bird-like figure with three curved lines representing its wings or feathers. The bird is positioned to the right of a circular arrangement of text that spells out "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA".

Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993

bioMérieux, Inc. c/o Jolyn Tenllado Director, Regulatory Affairs 595 Anglum Rd. Hazelwood, Missouri 63042

SEP 15 2011

Re: K112075

Trade/Device Name: VITEK® 2 Streptococcus Ampicillin Regulation Number: 21 CFRS 866.1645 Regulation Name: Short-Term Antimicrobial Susceptibility Test System Regulatory Class: Class II Product Code: LON Dated: July 19. 2011 Received: July 20, 2011

Dear Ms. Tenllado:

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 10 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. -

If your device is classified (see above) into class II (Special Controls), it may be subject to such additional controls. Existing major regulations affecting your device can be found in Title 21, Code of Federal Regulations (CFR). Parts 800 to 895. In addition, FDA may publish further announcements concerning vour 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 Parts 801 and 809); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); and good manufacturing practice

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Page 2 - Jolyn Tenllado

requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820). This letter will allow you to begin marketing your device as described in your Section 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus. permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Parts 801 and 809), please contact the Office of In Vitro Diagnostic Device Evaluation and Safety at (301) 796-5450. 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/ReportalProblem/default.htm for the CDRH's Office

of Surveillance and Biometrics/Division of Postmarket Surveillance.

You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at us toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address http://www.fda.gov/cdrh/industrv/support/index.html.

Sincerely yours,

Sally A. Hojvat, M.Sc., Ph.D. Director Division of Microbiology Devices Office of In Vitro Diagnostic Device Evaluation and Safety Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known): K112075

Device Name: VITEK® 2 Streptococcus Ampicillin ( ≤ 0.25 – ≥ 16 µg/mL)

Indications For Use:

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.

Prescription Use × (Part 21 CFR 801 Subpart D) AND/OR

Over-The-Counter Use (21 CFR 807 Subpart C)

(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of In Vitro Diagnostic Devices (OIVD)

Freddie M. Poole

Division Sign-Off

Office of In Vitro Diagnostic Device Evaluation and Safety

510(k) K112075

Regulation Number and Section

§ 866.1645 Fully automated short-term incubation cycle antimicrobial susceptibility system.

(a)
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.(b)
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.”