Predicate Devices

K935296, K923463, K003306, K030404, K993914, K033479, K041003, K041951

Reference Devices

Not Found

AI/ML (Artificial Intelligence / Machine Learning)

No
The device description details a rapid immunoassay based on antibody binding and visual interpretation of color lines, which is a traditional biological assay method and does not involve AI or ML.

Therapeutic

No.
This device is for in vitro diagnostic use, meaning it is used to detect substances (Clostridium difficile toxins A and B) in samples taken from the human body, not to directly treat or prevent a disease.

Diagnostic

Yes

Explanation: The "Intended Use / Indications for Use" section explicitly states, "The test is to be used as an aid in the diagnosis of C. difficile disease." This directly defines it as a diagnostic device.

SaMD (Software as a Medical Device)

No

The device description clearly outlines a physical immunoassay kit with reagents, a reaction window, and a visual interpretation of results, indicating it is a hardware-based in vitro diagnostic device, not software only.

IVD (In Vitro Diagnostic)

Yes, this device is an IVD (In Vitro Diagnostic).

The document explicitly states in the "Intended Use / Indications for Use" section: "FOR IN VITRO DIAGNOSTIC USE."

This statement, along with the description of the device being used to test fecal specimens for the presence of substances (toxins A and B) to aid in the diagnosis of a disease (C. difficile disease), clearly indicates that it is an in vitro diagnostic device.

PCCP (Predetermined Change Control Plan) Authorized

N/A

Overview

Intended Use / Indications for Use

The TOX A/B QUIK CHEK™ test is a rapid immunoassay for detecting Clostridium difficile toxins A and B in fecal specimens from persons suspected of having C. difficile disease. The test is to be used as an aid in the diagnosis of C. difficile disease and results should be considered in conjunction with the patient history. FOR IN VITRO DIAGNOSTIC USE.

Product codes

LLH

Device Description

The TOX A/B QUIK CHEK™ test uses antibodies specific for toxins A and B of C. difficile. The device contains a Reaction Window with two lines of immobilized antibodies. The test line ("T") contains antibodies against C. difficile toxins A and B. The other, representing a control line ("C"), contains anti-IgG antibodies. The Conjugate consists of antibodies to toxins A and B coupled to horseradish peroxidase. To perform the test, the fecal specimen is diluted with Diluent, and Conjugate is added to the diluted sample. The diluted sample-conjugate mixture is added to the Sample Well and the device is allowed to incubate at room temperature for 15 minutes. During the incubation, any toxin A and toxin B in the sample bind to anti-toxin antibody-peroxidase conjugate. The toxin-antibody complexes migrate through a filter pad to a membrage where they are captured by the immobilized anti-toxin antibodies in the line. The Reaction Well is subsequently washed with Wash Buffer, followed by the addition of Substrate. After up to a 10 minute incubation, the "T" reaction is examined visually for the appearance of a blue line. A blue line indicates a positive test. A positive "C" reaction, indicated by a blue line, onfirms that sample and all reagents were added in proper sequence and volume, that reagents were active at the time of performing the assay, and that proper sample migration occurred.

Mentions image processing

Not Found

Mentions AI, DNN, or ML

Not Found

Input Imaging Modality

Not Found

Anatomical Site

Not Found

Indicated Patient Age Range

Not Found

Intended User / Care Setting

Not Found

Description of the training set, sample size, data source, and annotation protocol

Not Found

Description of the test set, sample size, data source, and annotation protocol

Not Found

Summary of Performance Studies

Results from 5 studies (2 in-house studies and 3 on-site studies) are included in the summary. Results from the TOX A/B QUIK CHEK™ were compared to tissue culture assay.

Reproducibility: The reproducibility of the TOX A/B QUIK CHEK™ test was determined using known positive (n=6) and negative (n=2) fecal specimens that were coded and sorted to prevent their identification during testing. Testing was performed on-site at 3 laboratories, which tested the samples on 3 days. The samples produced the expected results 100% of the time.

Key Metrics

The TOX A/B QUIK CHEK™ test exhibited a sensitivity and specificity of 90.2% and 99.7%, respectively. The predictive positive and negative values were 98.6% and 97.9%, respectively, and the correlation was 98.0%.

Sensitivity: 90.2 (95% Cl: 84.1 - 94.2)
Specificity: 99.7 (95% Cl: 98.8 - 99.9)
Predictive Positive Value: 98.6 (95% Cl: 94.4 - 99.8)
Predictive Negative Value: 97.9 (95% Cl: 96.4 - 98.7)
Correlation: 98.0 (95% Cl: 97.8 - 98.2)

Predicate Device(s)

K935296, K923463, K003306, K030404, K993914, K033479, K041003, K041951

Reference Device(s)

Not Found

Predetermined Change Control Plan (PCCP) - All Relevant Information

Not Found

Regulation Number and Section

§ 866.2660 Microorganism differentiation and identification device.

(a)
Identification. A microorganism differentiation and identification device is a device intended for medical purposes that consists of one or more components, such as differential culture media, biochemical reagents, and paper discs or paper strips impregnated with test reagents, that are usually contained in individual compartments and used to differentiate and identify selected microorganisms. The device aids in the diagnosis of disease.(b)
Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to § 866.9.

Summary

0

TOX A/B QUIK CHEK™ 510(k)

JUL 25 2005

510(k) SUMMARY 7.

K050891

| Contact Information | David M. Lyerly
Vice-President, Research & Development
TECHLAB®, Inc.
2001 Kraft Drive
Corporate Research Center
Blacksburg, VA 24060-6364 |
|------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------|
| | Phone: 540-953-1664
FAX: 540-953-1665
Email: dlyerly@techlab.com |
| Date Prepared | April 5, 2005 |
| Product and Trade Name | TOX A/B QUIK CHEKTM |
| Classification | 21 CFR 866.2660 |

Predicate Devices

C. DIFFICILE TOX-B TEST (K935296) TECHLAB, Inc., Blacksburg, VA .
C. difficile toxin/antitoxin (K923463) TECHLAB, Inc., Blacksburg, VA
C. DIFFICILE TOX A/B IT™ (K003306 and K030404) TECHLAB, Inc., Blacksburg, VA .
Premier™ Toxins A&B (K993914) Meridian Bioscience, Inc., Cincinnati, OH ●
ProSpecT® Clostridium difficile Toxin A/B (K033479) Remel, Lenexa, KS .
ImmunoCard® Toxins A&B (K041003) Meridian Bioscience, Inc., Cincinnati, OH .
Xpect™ Clostridium difficile Toxin A/B (K041951) Remel Inc., Lenexa, KS .

Intended Use

The TOX A/B QUIK CHEK™ test is a rapid immunoassay for detecting Clostridium difficile toxins A and B in fecal specimens from persons suspected of having C. difficile disease. The test is to be used as an aid in the diagnosis of C. difficile disease and results should be considered in conjunction with the patient history.

Device Description

The TOX A/B QUIK CHEK™ test uses antibodies specific for toxins A and B of C. difficile. The device contains a Reaction Window with two lines of immobilized antibodies. The test line ("T") contains antibodies against C. difficile toxins A and B. The other, representing a control line ("C"), contains anti-IgG antibodies. The Conjugate consists of antibodies to toxins A and B coupled to horseradish peroxidase. To perform the test, the fecal specimen is diluted with Diluent, and Conjugate is added to the diluted sample. The diluted sample-conjugate mixture is added to the Sample Well and the device is allowed to incubate at room temperature for 15 minutes. During the incubation, any toxin A and toxin B in the sample bind to anti-toxin antibody-peroxidase conjugate. The toxin-antibody complexes migrate through a filter pad to a membrage where they are captured by the immobilized anti-toxin antibodies in the line. The

1

Reaction Well is subsequently washed with Wash Buffer, followed by the addition of Substrate. After up to a 10 minute incubation, the "T" reaction is examined visually for the appearance of a blue line. A blue line indicates a positive test. A positive "C" reaction, indicated by a blue line, onfirms that sample and all reagents were added in proper sequence and volume, that reagents were active at the time of performing the assay, and that proper sample migration occurred.

Comparative information of equivalent devices

| Characteristics | 510(K)
Numbers | Intended Use | Format | Materials | Target
Population |
|-------------------------------------------------|----------------------------|----------------------------------------------------------|---------------------|----------------------------------------------------------------------------|-----------------------------------------------------------|
| TOX A/B QUIK
CHEK™ test | Subject to
this 510(k) | Detection of C.
difficile toxin in
fecal specimens | Rapid
membrane | Highly specific
antibodies
against C.
difficile toxins A
and B | Persons
suspected of
having C.
difficile disease |
| Tissue culture
assay (TOX-B
TEST) | K935296 | Detection of C.
difficile toxin in
fecal specimens | Tissue
culture | Cell monolayer,
specific
neutralizing
antiserum | Persons
suspected of
having C.
difficile disease |
| C. DIFFICILE
TOX A/B II™ | K003306
and
KK030404 | Detection of C.
difficile toxin in
fecal specimens | Microtiter
ELISA | Highly specific
antibodies
against C.
difficile toxins A
and B | Persons
suspected of
having C.
difficile disease |
| Premier™ Toxins
A&B | K993914 | Detection of C.
difficile toxin in
fecal specimens | Microtiter
ELISA | Highly specific
antibodies
against C.
difficile toxins A
and B | Persons
suspected of
having C.
difficile disease |
| ProSpecT®
Clostridium
difficile Toxin A/B | K033479 | Detection of C.
difficile toxin in
fecal specimens | Microtiter
ELISA | Highly specific
antibodies
against C.
difficile toxins A
and B | Persons
suspected of
having C.
difficile disease |
| ImmunoCard®
Toxins A&B | K041003 | Detection of C.
difficile toxin in
fecal specimens | Rapid
membrane | Highly specific
antibodies
against C.
difficile toxins A
and B | Persons
suspected of
having C.
difficile disease |
| X/pect™
Clostridium
difficile Toxin A/B | K041951 | Detection of C.
difficile toxin in
fecal specimens | Rapid
membrane | Highly specific
antibodies
against C.
difficile toxins A
and B | Persons
suspected of
having C.
difficile disease |

2

Summary of Performance Data

Clinical Accuracy

The tables below show a summary of the clinical performance of the TOX A/B QUIK CHEK™ test. Results from 5 studies (2 in-house studies and 3 on-site studies) are included in the summary. Results from the TOX A/B QUIK CHEK™ were compared to tissue culture assay. The TOX A/B QUIK CHEK™ test exhibited a sensitivity and specificity of 90.2% and 99.7%, respectively. The predictive positive and negative values were 98.6% and 97.9%, respectively, and the correlation was 98.0%.

Summary of clinical performance comparing the TOX A/B QUIK CHEK™ test versus tissue culture assay.

n=842	Tiss Cult pos	Tiss Cult neg
TOX A/B QUIK CHEKTM pos	138	2
TOX A/B QUIK CHEKTM neg	15	687

		95% Cl
Sensitivity	90.2	84.1 - 94.2
Specificity	99.7	98.8 - 99.9
Predictive Positive Value	98.6	94.4 - 99.8
Predictive Negative Value	97.9	96.4 - 98.7
Correlation	98.0	97.8 - 98.2

Of the 2 tissue culture-negative/TOX A/B QUIK CHEK™-positive samples, 1 was negative in the TOX A/B If™ test. Of the 15 specimens that were tissue culture-positive/TOX A/B QUIK CHEK™-negative, 12 were negative in a commercial A+B ELISA.

Analytical Sensitivity

The test was consistently positive at a concentration of 0.63 ng/mL for toxin A and 1.25 ng/mL for toxin B.

3

Cross-Reactivity

Strains of C. difficile that produce toxins A and B, or only toxin B, were demonstrated to react in the TOX A/B QUIK CHEK™. The specificity of the TOX A/B QUIK CHEK™ test was evaluated by examining the reactivity of a wide range of common intestinal bacteria and intestinal pathogens in the assay. A summary of the results is shown below. The only non-C. difficile organism to react in the TOX A/B QUIK CHEK™ test was C. sordellii VPI 9048, which and to soxin HT (hemorrhagic toxin) and toxin LT (lethal toxin) that are homologous to toxins A and B, respectively. All of the other organisms tested were negative in the TOX A/B QUIK CHEKTM.

| Bacterium difficile negative
stool | Reaction with C.
difficile positive
stool |
|---------------------- | Aeromonas hydrophila | Bacillus cereus | Bacillus subtilis | Bacteroides fragilis | Campylobacter coli | Campylobacter fetus | Campylobacter jejuni | Candida albicans | Clostridium bifermentans | Clostridium butyricum | Clostridium | Clostridium septicum | Clostridium sordellii | Clostridium sordellii | Clostridium sporogenes | Enterococcus faecalis | Escherichia coli EIEC | Escherichia coli | Escherichia coli O157 H7 | Escherichia coli ETEC | Klebsiella pneumoniae | Peptostreptococcus anaerobius | Proteus vulgaris | Pseudomonas aeruginosa | Salmonella typhimurium | Shigella dysenteriae | Shigella flexneri | Shigella sonnei | Bacterium | Staphylococcus aureus (Cowans) | Staphylococcus epidermidis | Vibrio parahaemolyticus | Yersinia enterocolitica | Strain | Reaction with C.
------------|------------|-------------------------------------------------|-------------------------------------------------|
| ATCC 7965 | - | + |
| ATCC 14579 | - | + |
| ATCC 6051 | - | + |
| VPI 13785 | - | + |
| ATCC 49941 | - | + |
| ATCC 25936 | - | + |
| ATCC 29428 | - | + |
| ATCC 10231 | - | + |
| VPI 2012 | - | + |
| VPI 8260 | - | + |
perfringens, types A | VPI 3624 | - | + |
| VPI 1524 | - | + |
| VPI 9048 | + | + |
| VPI 7319 | - | + |
| VPI 9743 | - | + |
| ATCC 19433 | - | + |
| SD67 | - | + |
| ATCC 25922 | - | + |
| B1409 | - | + |
| E 2348169 | - | + |
| ATCC 9997 | - | + |
| ATCC 27337 | - | + |
| ATCC 6380 | - | + |
| ATCC 9027 | - | + |
| ATCC 14029 | - | + |
| ATCC 12022 | - | + |
| ATCC 12122 | - | + |
| ATCC 11060 | - | + |
| Strain | Reaction with C. difficile negative stool | Reaction with C. difficile positive stool |
| ATCC 12598 | - | + |
| VPI 13140 | - | + |
| ATCC 17802 | - | + |
| ATCC 9610 | - | + |

4

| Virus | ATCC# | Reaction with C.
difficile negative
stool | Reaction with C.
difficile positive
stool |
|---------------------|---------|-------------------------------------------------|-------------------------------------------------|
| Adenovirus type 1 | VR-1 | - | + |
| Adenovirus type 2 | VR-846 | - | + |
| Adenovirus type 3 | VR-3 | - | + |
| Adenovirus type 5 | VR-5 | - | + |
| Adenovirus type 40 | VR-931 | - | + |
| Adenovirus type 41 | VR-930 | - | + |
| Human coronavirus | VR-740 | - | + |
| Coxsackievirus B2 | VR-29 | - | + |
| Coxsackievirus B3 | VR-30 | - | + |
| Coxsackievirus B4 | VR-184 | - | + |
| Coxsackievirus B5 | VR-185 | - | + |
| Echovirus 9 | VR-1050 | - | + |
| Echovirus 11 | VR-1052 | - | + |
| Echovirus 18 | VR-48 | - | + |
| Echovirus 22 | VR-1063 | - | + |
| Echovirus 33 | VR-582 | - | + |
| Enterovirus type 68 | VR-1076 | - | + |
| Enterovirus type 69 | VR-1077 | - | + |
| Enterovirus type 70 | VR-836 | - | + |
| Enterovirus type 71 | VR-784 | - | + |

5

Interfering Substances

The following substances had no effect on test results, either with C. difficile-negative or C. difficile-positive specimens, when present in the stool in the concentrations indicated in the table.

Substance	Concentration	Reaction with C. difficile negative stool	Reaction with C. difficile positive stool
Hog gastric mucin	3.5% w/v	-	+
Human blood (O, Rh-)	40% v/v	-	+
Barium sulfate	5% w/v	-	+
Imodium®	5% w/v	-	+
Kaopectate®	5 mg/ml	-	+
Pepto-Bismol®	5% w/v	-	+
Steric/palmitic acid	40% w/v	-	+
Metronidazole	0.25% w/v	-	+
Vancomycin	0.25% w/v	-	+

Reproducibility

The reproducibility of the TOX A/B QUIK CHEK™ test was determined using known positive (n=6) and negative (n=2) fecal specimens that were coded and sorted to prevent their identification during testing. Testing was performed on-site at 3 laboratories, which tested the samples on 3 days. The samples produced the expected results 100% of the time.

6

REFERENCES 8.

1. Bartlett JG. 1990. Clostridium difficile: clinical considerations. Rev. Infect. Dis. 12:S243-51
Dartlett JG. 1998. Clostridium difficile Associated diarrhea and colitis. In Infectious 2. Diseases, 2nd Ed., (eds) Gorbach SL, Bartlett JG, and Blacklow NR, W.B. Saunders Company, Philadelphia, London, Toronto, Montreal, Sydney, Tokyo
1. Lyerly DM, Wilkins TD. 1995. Clostridium difficile. In Infections of the Gastrointestinal Tract (eds) Blaser MJ, Smith PD, Ravdin Jl, Greenberg HB, and Guerrant RL Raven Press, Ltd., New York, pp 867-91
4 Lyerly DM, Neville LM, Evans DT, Fill J, Allen S, Greene W, Sautter R, Hnatuck P, Torpey D, Schwalbe R. 1998. Multicenter evaluation of the Clostridium difficile TOX A/B TEST. J. Clin. Microbiol. 36:184-90
1. Kato H, Kato N, Watanabe K, Iwai N, Nakamura H, Yamamoto T, Suzuki K, Kim S-M, Chong Y, Wasito EB. 1998. Identification of toxin A-negative, toxin B-positive Clostridium difficile by PCR. J. Clin. Microbiol. 36:2178-82
1. Alfa MJ, Kabani A, Lyerly D, Moncrief S, Neville LM, Al-Barrak A, Harding GK, Dyck B, Olekson K, Embil JM. 2000. Characterization of a toxin A-negative, toxin B-positive strain of Clostridium difficile responsible for a nosocomial outbreak of Clostridium difficileassociated diarrhea. J. Clin. Microbiol. 38:2706-14
1. Kraft D. 1999. Personal communications.
Kato H, Kato N, Katow S, Maegawa T, Nakamura S, Lyerly DM. 1999. Deletion in the 8. repeating sequences of toxin A gene of toxin A-negative, toxin B-positive Clostridium difficile strains. FEMS Microbiol. Lett. 175:197-203
1. Moncrief JS, Zheng L, Neville LM, Lyerly DM. 2000. Genetic characterization of toxin Anegative, toxin B-positive Clostridium difficile isolates by PCR. J. Clin. Microbiol. 38:3072-5
1. von Eichel-Streiber C, Zec-Pirnat I, Grabnar M, Rupnik M. 1999. A nonsense mutation abrogates production of a functional enterotoxin A in Clostridium difficile toxinotype VIII strains of serogroups F and X. FEMS Microb. Lett. 178:163-8
1. Fluit AC, Wolfhagen MJHM, Verdonk GPHT, Jansze M, Torensma R, Verhoef J. 1991. Nontoxigenic strains of Clostridium difficile lack the genes for both toxin A and toxin B. J. Clin. Microbiol. 29:2666-7
1. Anderson BM, Anderson CD, Van Tassell RL, Lyerly DM, Wilkins TD. 1993. Purification and characterization of Clostridium difficile glutamate dehydrogenase. Archives Biochem. Biophy. 300:483-8
1. Lyerly DM, Barroso LA, Wilkins TD. 1991. Identification of the latex test-reactive protein of Clostridium difficile as glutamate dehydrogenase. J. Clin. Microbiol. 29:2639-42
1. Miles BL, Siders JA, Allen SD. 1988. Evaluation of a commercial latex test for Clostridium difficile for reactivity with C. difficile and cross-reactions with other bacteria. J. Clin. Microbiol. 26:2452-5
1. Lyerly DM, Ball DW, Toth J, Wilkins TD. 1988. Characterization of cross-reactive proteins detected by Culturette Brand Rapid Latex Test for Clostridium difficile. J. Clin. Microbiol. 26:397-400
1. Landry ML, Topal J, Ferguson D, Giudetti D, Tang Y. 2001. Evaluation of Biosite Triage Clostridium difficile panel for rapid detection of Clostridium difficile in stool samples. J. Clin. Microbiol 39:1855-8

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1. Alfa MJ, Swan B, VanDekerkhove B, Pang P, Harding GK. 2002. The diagnosis of Clostridium difficile-associated diarrhea: comparison of Triage C. difficile panel, EIA for Tox A/B and cytotoxin assays. Diagn. Microbiol. Infect. Dis 43:257-63
1. Turgeon DK, Novicki TJ, Quick J, Carlson L, Miller P, Ulness B, Cent A, Ashley R, Larson A. Coyle M, Limaye AP, Cookson BT, Fritsche TR. 2003. Six Rapid Tests for Direct Detection of Clostridium difficile and Its Toxins in Fecal Samples Compared with the Fibroblast Cytotoxicity Assay. J. Clin. Microbiol. 41:667-70
1. Gumerlock PH, Tang YJ, Meyers FJ, Silva J, Jr. 1991. Use of the polymerase chain reaction for the specific and direct detection of Clostridium difficile in human feces. Rev. Infect. Dis. 13:1053- 60
1. Gumerlock PH, Tang YJ, Weiss JB, Silva J, Jr. 1993. Specific detection of toxigenic strains of Clostridium difficile in stool specimens. J. Clin. Microbiol. 31:507-11
1. Boondeekhun HS, Gurtler V, Odd ML, Wilson VA, Mayall BC. 1993. Detection of Clostridium difficile enterotoxin gene in clinical specimens by the polymerase chain reaction. J. Med. Microbiol. 38:385-7
1. Lou Q, Chong SKF, Fitzgerald JF, Siders JA, Allen SD, and Lee C-H. 1997. Rapid and effective method for preparation of fecal specimens for PCR assays. J. Clin. Microbiol. 35:281-3
1. Kato N, Ou C-Y, Kato H, Bartley SL, Luo C-C, Killgore G.E, and Ueno K. 1993. Detection of toxigenic Clostridium difficile in stool specimens by the polymerase chain reaction. J. Infect. Dis. 167:455-8
1. Rupnik M, Avesani V, Janc M, von Eichel-Streiber C, Delmee M. 1998. A novel toxinotyping scheme and correlation of toxinotypes with serogroups of Clostridium difficile isolates. J. Clin. Microbiol. 36:2240-7
1. Bélanger SD, Biossinot M, Clairoux N, Picard FJ, Bergeron MG. 2003. Rapid detection of Clostridium difficile in feces by real-time PCR. J. Clin. Microbiol. 41:730-4
1. Guilbault C, Labbe A-C, Poirier L, Busque L, Beliveau C Laverdiere M. 2002. Development and evaluation of a PCR method for detection of the Clostridium difficile toxin B gene in stool specimens. J. Clin. Microbiol. 40:2288-90
1. Wolfhagen MJHM, Fluit AC, Torensma R, Poppelier MJJG, Verhoef J. 1994. Rapid detection of toxigenic Clostridium difficile in fecal samples by magnetic immuno PCR assay. J. Clin. Microbiol. 32:1629-33
1. Summanen P, Baron EJ, Citron DM, Strong C, Wexler HM, Fingold SM, Wadsworth Anaerobic Bacteriology Manual, Fifth Edition. 1993. Star publishing company, Belmont, California

8

Image /page/8/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular seal with the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged around the perimeter. Inside the circle is an abstract symbol that resembles three stylized human profiles facing to the right, stacked on top of each other.

JUL 2 5 2005

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

David M. Lyerly, Ph.D. Vice President, Research and Development TECHLAB®, Inc. 2001 Kraft Drive Corporate Research Center Blackburg, VA 24060-6358

K050891 Re:

Trade/Device Name: TOX A/B QUICK CHECK™ Regulation Number: 21 CFR 866.2660 Regulation Name: Microorganism differentiation and identification device Regulatory Class: Class I Product Code: LLH Dated: July 5, 2005 Received: July 8, 2005

Dear Dr. Lyerly:

We have reviewed your Section 510(k) premarket notification of intent to market the device w 6 nave ro rowed your be determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate for ass surfal in the energe, 1976, the enactment date of the Medical Device Amendments, or to 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). and Cosmeter rear (110) that the device, subject to the general controls provisions of the Act. The I ou may, dicrororo, mainer of the Act include requirements for annual registration, listing of general controlo provisioning practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), 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 your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean I lease be advised that I Drivines and evice complies with other requirements of the Act that I Dri has made a actoring administered by other Federal agencies. You must or any it cacal statuted and regainents, including, but not limited to: registration and listing (21 Comply with an the morts 801 and 809); and good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820).

9

Page 2 -

This letter will allow you to begin marketing your device as described in your Section 510(k) I mis lotter will and in your 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 information about the application of labeling requirements to your device, or questions on the promotion and advertising of your device, please contact the Office of In Vitro Diagnostic Device Evaluation and Safety at (240)276-0484. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). You may obtain other general information on your responsibilities under the Act from the I va may other of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/industry/support/index.html

Sincerely yours,

Sally, a Form

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

10

REVISED

Indications for Use

510(k) Number (if known):_____________________________________________________________________________________________________________________________________________________ K020891

Device Name:__________________________________________________________________________________________________________________________________________________________________

Indications For Use:

The TOX A/B QUIK CHEK™ test is a rapid immunoassay for detecting Clostridium difficile toxins A and B in fecal specimens from persons suspected of having C. difficile disease. The test is to be used as an aid in the diagnosis of C. difficile disease C. unfrette disease. The test to a conjunction with the patient history. FOR IN VITRO DIAGNOSTIC USE.

Prescription Use _____________________________________________________________________________________________________________________________________________________________

AND/OR

Over-The-Counter Use

(Part 21 CFR 801 Subpart D)

(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 L. Poole

Division Sign-Off

Page 1 of ____________________________________________________________________________________________________________________________________________________________________

Office of In Vitro Diagnostic Device Evaluation and Safety

510(k) K050891