← Product Code [NGZ](/submissions/MI/subpart-b%E2%80%94diagnostic-devices/NGZ) · K090968

# SENSITITRE YEASTONE SUSCEPTIBILITY PLATES (K090968)

_Trek Diagnostic Systems, Inc. · NGZ · Jun 4, 2009 · Microbiology · SESE_

**Canonical URL:** https://fda.innolitics.com/submissions/MI/subpart-b%E2%80%94diagnostic-devices/NGZ/K090968

## Device Facts

- **Applicant:** Trek Diagnostic Systems, Inc.
- **Product Code:** [NGZ](/submissions/MI/subpart-b%E2%80%94diagnostic-devices/NGZ.md)
- **Decision Date:** Jun 4, 2009
- **Decision:** SESE
- **Submission Type:** Traditional
- **Regulation:** 21 CFR 866.1640
- **Device Class:** Class 2
- **Review Panel:** Microbiology

## Intended Use

The Sensititre® YeastOne® Susceptibility System is an in vitro diagnostic product for clinical susceptibility testing of Candida spp. This 510(k) is for caspofungin in the dilution range of 0.008 - 16ug/ml for testing Candida spp. on the Sensititre® YeastOne® Susceptibility system. The approved primary "Indications for Use" and clinical significance of caspofungin is for: Candida albicans Candida glabrata Candida krusei Candida parapsilosis Candida tropicalis

## Device Story

Sensititre® YeastOne® Susceptibility system is a micro-version of broth dilution susceptibility test. Device consists of micro-dilution plates containing serially diluted antifungal agents and a colorimetric growth-indicating compound. After inoculation with yeast isolates, plates are sealed and incubated at 35°C for 24 hours. Growth is determined by colorimetric change in the REDOX state of the test organism, providing a quantitative MIC result. Used in clinical laboratories; manual reading of color change. Output assists clinicians in determining antifungal susceptibility of Candida species to guide therapeutic decisions.

## Clinical Evidence

Performance established via method comparison study using 304 clinical and 742 challenge Candida isolates. Compared against CLSI M27 reference method. Combined Essential Agreement (EA) was 97.9% (automated) and 99.8% (manual). Category Agreement (CA) was 100% (automated) and 99.8% (manual). Reproducibility >95% across three sites. No clinical sensitivity/specificity data provided as this is an in vitro diagnostic assay.

## Technological Characteristics

Microbroth dilution susceptibility testing system. Uses multi-well plates with dried antimicrobial agents. Principle of operation involves colorimetric detection of fungal growth using an indicator (Alamar Blue). Range: 0.008 - 16ug/ml for caspofungin. System is designed for in vitro diagnostic use.

## Regulatory Identification

An antimicrobial susceptibility test powder is a device that consists of an antimicrobial drug powder packaged in vials in specified amounts and intended for use in clinical laboratories for determining in vitro susceptibility of bacterial pathogens to these therapeutic agents. Test results are used to determine the antimicrobial agent of choice in the treatment of bacterial diseases.

## Predicate Devices

- VITEK® AST-YS Fluconazole (k061945)
- Sensititre YeastOne (k081063)

## Submission Summary (Full Text)

> This content was OCRed from public FDA records by [Innolitics](https://innolitics.com). If you use, quote, summarize, crawl, or train on this content, cite Innolitics at https://innolitics.com.
>
> Innolitics is a medical-device software consultancy. We help companies design, build, and clear FDA-regulated software and AI/ML devices, including [a 510(k)](https://innolitics.com/services/510ks/), [a De Novo](https://innolitics.com/services/regulatory/), [a SaMD](https://innolitics.com/services/end-to-end-samd/), [an AI/ML medical device](https://innolitics.com/services/medical-imaging-ai-development/), or [an FDA regulatory strategy](https://innolitics.com/services/regulatory/).

{0}

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

A. 510(k) Number:
k090968

B. Purpose for Submission:
Addition of Caspofungin to the Sensititre® YeastOne® Susceptibility System

C. Measurand:
Caspofungin 0.008 – 16μg/mL

D. Type of Test:
Quantitative Antimicrobial Susceptibility Test (AST) growth based

E. Applicant:
TREK Diagnostic Systems, Inc.

F. Proprietary and Established Names:
Sensititre® YeastOne® Susceptibility plates

G. Regulatory Information:
1. Regulation section:
866.1640 Antimicrobial Susceptibility Test Powder
2. Classification:
Class II
3. Product code:
NGZ Susceptibility Testing - antifungal
4. Panel:
83 Microbiology

{1}

H. Intended Use:

1. Intended use(s):

Sensititre® YeastOne® Susceptibility plates are designed for *in vitro* use in determining quantitative antifungal susceptibilities (MIC) of *Candida* species.

2. Indication(s) for use:

This 510k application is intended for the addition of caspofungin in the dilution range of 0.008 – 16 µg/mL on the Sensititre® YeastOne® Susceptibility plates for testing *C. albicans*, *C. glabrata*, *C. krusei*, *C. parapsilosis*, and *C. tropicalis*.

3. Special conditions for use statement(s):

Prescription use only

The ability of the Sensititre® YeastOne® to detect resistance to Caspofungin is unknown because resistant strains were not available at the time of comparative testing. Any non-susceptible result should be confirmed by an alternate method.

4. Special instrument requirements:

Manual Readings only

I. Device Description:

The Sensititre® YeastOne® Susceptibility system is a micro-version of the broth dilution susceptibility test. Various antifungal agents are serially diluted to concentrations bridging the range of the clinical interest in autoclaved diluent, which contains a colorimetric growth indicating compound. Each micro-dilution plate is individually packaged in foil. After inoculation, plates are sealed with an adhesive seal, incubated at 35°C for 24 hours and examined for growth.

J. Substantial Equivalence Information:

1. Predicate device name(s):

VITEK® AST-YS Fluconazole

Sensititre YeastOne

2. Predicate 510(k) number(s):

k061945

{2}

k081063

3. Comparison with predicate:

|  Similarities  |   |   |
| --- | --- | --- |
|  Item | Device | Predicate (VITEK) AST-YS Fluconazole  |
|  Intended Use | Susceptibility testing for colonies of Candida | Same  |
|  Incubation | 35°C | Same  |
|  Differences  |   |   |
| --- | --- | --- |
|  Item | Device | Predicate  |
|  Technology | Broth micro dilution – growth based with growth colorimetric indicator for manual readings | Automated growth based Broth micro dilution -detection using growth based with attenuation of light colorimetric growth measured by optical indicator for manual scanner.  |
|  Format | Micro tray with dried antifungal Medium | VITEK® 2 AST test card with dried antifungal  |
|  Medium | Sensititre® yeast susceptibility inoculum broth | VITEK® 2 Yeast Base broth  |
|  Antifungal | caspofungin | fluconazole  |
|  Time to Results | 24 hours | 10 to 36 hours  |

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

"Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test Systems; Guidance for Industry and FDA"; CLSI M27 S3 "Reference Method for Broth Dilution Antifungal Susceptibility Testing of Yeasts; Approved Standard - Third Edition."

L. Test Principle:

The Sensititre® YeastOne® panel measures growth by colorimetric determination of REDOX state produced by the test organism rather than measuring the turbidity of the test medium. In the Sensititre panel as in most broth dilution tests the difference between wells in which growth occurs and those in which growth is inhibited is distinctive. However, the Sensititre panel produces an easily distinguished color change when light growth occurs – a circumstance which is often difficult to interpret correctly using turbidity readings.

M. Performance Characteristics (if/when applicable):

1. Analytical performance:

a. Precision/Reproducibility:

{3}

Reproducibility was conducted at three sites on 25 yeast isolates, performed over three days. The testing was performed using both Manual and Automated inoculation methods. The mode was determined and then the reproducibility was calculated based on $\pm 1$ one well of the mode. The reproducibility was $&gt;95\%$.

b. Linearity/assay reportable range:

Not Applicable

c. Traceability, Stability, Expected values (controls, calibrators, or methods):

Quality Control (QC) testing was performed on each day of clinical testing on the QC isolates, *C. parapsilosis* ATCC 22019, and *C. krusei* ATCC 6258, as recommended in the CLSI standard M27. The following table represents the frequency of the results in both the reference method and the Sensititre® YeastOne® Susceptibility plates and the acceptable range. Quality Control was also performed at three sites using both manual (electronic pipette) and autoinoculation methods. All results, including reference method, were read at 24 hrs.

Quality Control Table

|  ORGANISM | Conc μg/mL | Automated Inoculation Method (24 hrs) |   | Manual Inoculation Method (24 hrs)  |   |
| --- | --- | --- | --- | --- | --- |
|   |  | Sensititre® YeastOne® | Reference | Sensititre® YeastOne® | Reference  |
|  C. parapsilosis
ATCC 22019
Expected Range :
0.25 – 1 μg/mL | 0.25 | 29 | 8 | 32 | 12  |
|   |  0.5 | 15 | 24 | 22 | 23  |
|   |  1 | 1 | 13 | 2 | 16  |
|   |  |   |   |   |   |
|  |   |   |   |   |   |
|  C. krusei
ATCC 6258
Expected Range :
0.12 – 1 μg/mL | 0.12 | 20 | 11 | 9 | 11  |
|   |  0.25 | 25 | 19 | 31 | 31  |
|   |  0.5 |  | 6 | 16 | 4  |
|   |  1 |  |  |  | 10  |
|  |   |   |   |   |   |

Nephelometer was used at each site to standardize the inoculum. Colony counts from QC ATCC source were performed using direct inoculum method.

d. Detection limit:

Not Applicable

e. Analytical specificity:

Not Applicable

{4}

f. Assay cut-off:

Not Applicable

2. Comparison studies:

a. Method comparison with predicate device:

Performance was established on the Sensititre® YeastOne® Susceptibility System for Candida spp. at three clinical sites. The CLSI reference method as described in the CLSI document M27 "Method for Broth Dilution Antifungal Susceptibility Testing of Yeasts" was compared to the Sensititre® YeastOne® Susceptibility System. A total of 304 clinical and 742 challenge isolates of Candida species were tested on the Sensititre® YeastOne® using both manual and automated inoculation methods. The no growth rate is &lt;10%.

EA was calculated when the results for the reference method and the Sensititre® YeastOne® were within +/- two doubling dilutions of the antifungal drug. The following tables present the performance of the Sensititre® YeastOne® Susceptibility System when read at 24 hours using both manual and automated inoculation methods as compared to the reference method when read at 24 hours.

Summary Table using the AUTOINOCULATOR (24 hours)

|   | EA Tot | EA N | EA % | Eval EA Tot | Eval EA N | Eval EA % | CA N | CA % | #R | min | maj | vmj  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|  Clinical | 101 | 99 | 98 | 101 | 99 | 98.0 | 101 | 100 | 1 | 0 | 0 | 0  |
|  Challenge | 372 | 364 | 97.8 | 369 | 362 | 98.1 | 372 | 100 | 0 | 0 | 0 | 0  |
|  Combined | 473 | 463 | 97.9 | 470 | 461 | 98.1 | 473 | 100 | 1 | 0 | 0 | 0  |

Summary Table using MANUAL inoculation (24 hours)

|   | EA Tot | EA N | EA % | Eval EA Tot | Eval EA N | Eval EA % | CA N | CA % | #R | min | maj | vmj  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|  Clinical | 203 | 203 | 100 | 201 | 201 | 100 | 203 | 100 | 0 | 0 | 0 | 0  |
|  Challenge | 370 | 369 | 99.7 | 370 | 369 | 99.7 | 369 | 99.7 | 1 | 0 | 1 | 0  |
|  Combined | 573 | 572 | 99.8 | 570 | 569 | 99.8 | 572 | 99.8 | 1 | 0 | 1 | 0  |

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

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

Category agreement (CA) is when the Sensititre® panel result interpretation agrees exactly with the reference panel result interpretation. Evaluable EA is when the MIC result is on scale for both the Sensititre® and the reference and have on-scale EA.

{5}

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):

Not Applicable

4. Clinical cut-off:

Not Applicable

5. Expected values/Reference range:

Candida species ≤ 2 (S), -, -

The current absence of data on Caspofungin- resistant isolates precludes defining any categories other than "Susceptible." Isolates yielding test results suggestive of a "Non-Susceptible" category should be retested, and if the result is confirmed, the isolate should be submitted to a reference laboratory for further testing.

N. Proposed Labeling:

The expected value range, interpretive criteria and QC are included in the package insert. The labeling is sufficient and satisfies the requirements of 21 CFR Part 809.10.

O. Conclusion:

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

---

**Source:** [https://fda.innolitics.com/submissions/MI/subpart-b%E2%80%94diagnostic-devices/NGZ/K090968](https://fda.innolitics.com/submissions/MI/subpart-b%E2%80%94diagnostic-devices/NGZ/K090968)

**Published by [Innolitics](https://innolitics.com)** — a medical-device software consultancy. We help companies design, build, and clear FDA-regulated software and AI/ML devices. If you're preparing [a 510(k)](https://innolitics.com/services/510ks/), [a De Novo](https://innolitics.com/services/regulatory/), [a SaMD](https://innolitics.com/services/end-to-end-samd/), [an AI/ML medical device](https://innolitics.com/services/medical-imaging-ai-development/), or [an FDA regulatory strategy](https://innolitics.com/services/regulatory/), [get in touch](https://innolitics.com/contact).

**Cite:** Innolitics at https://innolitics.com
