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.

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.

AI/ML Overview

TOX A/B QUIK CHEK™ 510(k) Summary

This document describes the acceptance criteria and the studies that demonstrate the TOX A/B QUIK CHEK™ device meets these criteria for detecting Clostridium difficile toxins A and B in fecal specimens.

1. Acceptance Criteria and Reported Device Performance

The acceptance criteria for the TOX A/B QUIK CHEK™ device are not explicitly stated as numerical targets in the provided text. However, based on the Summary of Performance Data, the reported device performance is presented as follows, which can be inferred as the criteria the device met for clearance.

Metric	Acceptance Criteria (Inferred)	Reported Device Performance
Sensitivity	High (for diagnostic aid)	90.2% (95% CI: 84.1 - 94.2)
Specificity	High (for diagnostic aid)	99.7% (95% CI: 98.8 - 99.9)
Predictive Positive Value (PPV)	High (for diagnostic aid)	98.6% (95% CI: 94.4 - 99.8)
Predictive Negative Value (PNV)	High (for diagnostic aid)	97.9% (95% CI: 96.4 - 98.7)
Correlation	High (for diagnostic aid)	98.0% (95% CI: 97.8 - 98.2)
Cross-Reactivity	Minimal with non-C. difficile	Only C. sordellii VPI 9048 reacted among tested common intestinal bacteria and pathogens. No cross-reactivity with tested viruses or interfering substances.
Analytical Sensitivity	Ability to detect low concentrations of toxins	Consistently positive at 0.63 ng/mL for toxin A and 1.25 ng/mL for toxin B.
Reproducibility	Consistent results across sites and days	100% agreement with expected results in a 3-site, 3-day study.

2. Sample Size and Data Provenance for the Test Set

Sample Size for Test Set: 842 fecal specimens.
Data Provenance: The study was a "clinical performance" study, including "5 studies (2 in-house studies and 3 on-site studies)". The country of origin is not explicitly stated. The nature of the studies (in-house and on-site) suggests these were prospective or a combination of prospective and retrospective collections for clinical validation. It is not explicitly stated whether the data was retrospective or prospective, but clinical performance studies typically involve prospective data collection or a mix of archived and newly collected specimens.

3. Number of Experts and Qualifications for Ground Truth

The document does not explicitly state the number of experts used or their specific qualifications (e.g., radiologist with 10 years of experience) for establishing the ground truth.

4. Adjudication Method for the Test Set

The document does not describe any specific adjudication method (e.g., 2+1, 3+1, none) for the test set.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

No Multi-Reader Multi-Case (MRMC) comparative effectiveness study was mentioned. The device is a rapid immunoassay, which typically does not involve human readers interpreting complex images or data in a comparative effectiveness study format.

6. Standalone Performance Study

Yes, a standalone performance study was done. The "Summary of clinical performance" section directly compares the "TOX A/B QUIK CHEK™ test" results against the "tissue culture assay" as the ground truth. This evaluates the algorithm-only performance.

7. Type of Ground Truth Used

The ground truth used for the clinical accuracy evaluation was a tissue culture assay. Specifically, for the comparative performance table, "Tissue culture assay" results were used as the reference standard (Tiss Cult pos/neg).

8. Sample Size for the Training Set

The document does not explicitly state a separate "training set" or its sample size. For an immunoassay, the development and optimization of antibodies and assay conditions (analytical sensitivity, cross-reactivity, interfering substances) would involve internal studies that serve a similar function to a training set in machine learning. The clinical performance data presented here is typically considered the validation or test set for regulatory submission.

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

As no explicit training set is mentioned in the context of clinical accuracy, the ground truth establishment for a training set is not detailed. However, the comprehensive analytical studies (analytical sensitivity, cross-reactivity, interfering substances) would have relied on established laboratory reference methods and defined concentrations of toxins or specific organisms to characterize the device's behavior during its development phase.

Summary

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TOX A/B QUIK CHEK™ 510(k)

JUL 25 2005

510(k) SUMMARY 7.

K050891

Contact Information	David M. LyerlyVice-President, Research & DevelopmentTECHLAB®, Inc.2001 Kraft DriveCorporate Research CenterBlacksburg, VA 24060-6364
	Phone: 540-953-1664FAX: 540-953-1665Email: 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

Device Description

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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	TargetPopulation
TOX A/B QUIKCHEK™ test	Subject tothis 510(k)	Detection of C.difficile toxin infecal specimens	Rapidmembrane	Highly specificantibodiesagainst C.difficile toxins Aand B	Personssuspected ofhaving C.difficile disease
Tissue cultureassay (TOX-BTEST)	K935296	Detection of C.difficile toxin infecal specimens	Tissueculture	Cell monolayer,specificneutralizingantiserum	Personssuspected ofhaving C.difficile disease
C. DIFFICILETOX A/B II™	K003306andKK030404	Detection of C.difficile toxin infecal specimens	MicrotiterELISA	Highly specificantibodiesagainst C.difficile toxins Aand B	Personssuspected ofhaving C.difficile disease
Premier™ ToxinsA&B	K993914	Detection of C.difficile toxin infecal specimens	MicrotiterELISA	Highly specificantibodiesagainst C.difficile toxins Aand B	Personssuspected ofhaving C.difficile disease
ProSpecT®Clostridiumdifficile Toxin A/B	K033479	Detection of C.difficile toxin infecal specimens	MicrotiterELISA	Highly specificantibodiesagainst C.difficile toxins Aand B	Personssuspected ofhaving C.difficile disease
ImmunoCard®Toxins A&B	K041003	Detection of C.difficile toxin infecal specimens	Rapidmembrane	Highly specificantibodiesagainst C.difficile toxins Aand B	Personssuspected ofhaving C.difficile disease
X/pect™Clostridiumdifficile Toxin A/B	K041951	Detection of C.difficile toxin infecal specimens	Rapidmembrane	Highly specificantibodiesagainst C.difficile toxins Aand B	Personssuspected ofhaving C.difficile disease

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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.

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

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Virus	ATCC#	Reaction with C.difficile negativestool	Reaction with C.difficile positivestool
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	-	+

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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.

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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

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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).

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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

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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

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.