REMEL's Xpect™ Cryptosporidium kit is an in vitro qualitative immunoassay for the detection of Cryptosporidium antigens in preserved and unpreserved fecal specimens. This test is intended as an aid in the laboratory diagnosis of suspected Cryptosporidium infections.

Device Description

The Xpect™ Cryptosporidium Lateral Flow Assay is a chromatographic immunoassay that detects the presence of Cryptosporidium antigen. The test utilizes sample wicking to capture Cryptosporidium antigen on a test line containing antigen-specific antibody. A specimen is added to a dilution tube containing a buffered solution. A conjugate containing colored micro-particles linked to murine monoclonal antibody specific for Cryptosporidium is added. The mixture is dispensed into the sample well of the device and wicks along a membrane containing capture antibody stripes. The Cryptosporidium immune complex, if present, reacts with anti-Cryptosporidium antibody at the test line. Conjugate not bound at the test line is later captured at the control line containing anti-mouse antibody. A red line of any intensity will appear at the Cryptosporidium test position if Cryptosporidium antigen is present. A line in the Control position indicates that the test is working properly.

AI/ML Overview

Here's a summary of the acceptance criteria and study details for the Xpect™ Cryptosporidium Lateral Flow Assay, based on the provided 510(k) notification:

Acceptance Criteria and Device Performance

Acceptance Criteria Category	Acceptance Criteria	Reported Device Performance
Sensitivity	Not explicitly stated (implied to be high enough for clinical utility relative to microscopy)	96.4% (95% CI: 91.2-98.6%)
Specificity	Not explicitly stated (implied to be high enough for clinical utility relative to microscopy)	98.3% (95% CI: 96.6-99.1%)
Cross-Reactivity	No cross-reactivity with common intestinal parasites and bacteria.	No cross-reactivity observed with 24 specified organisms, including Ascaris lumbricoides, Blastocystis hominis, Campylobacter coli, Giardia lamblia, and others.
Interfering Substances	No interference with common substances (blood, mucin, fecal fat) and anti-diarrheal products.	No interference observed with blood, mucin, fecal fat, Pepto-Bismol®, and Kaopectate®. Interference observed with Imodium® A-D at 20% (v/v) for low levels of Cryptosporidium antigen.
Reproducibility	Consistent results across different sites and days.	100% agreement with expected results for 630 samples tested across seven sites (including one in-house site) over three days.
Percent Agreement vs. Microscopy (for comparison with predicate)	Not explicitly stated, but typically a high percentage agreement is expected.	94.5% for Xpect™ Cryptosporidium (vs. microscopy), 84.9% for Predicate Device (vs. microscopy)

Study Details

Sample sizes used for the test set and data provenance:
- Sensitivity/Specificity Study:
  - Total Samples: 578 (112 positive for Cryptosporidium by microscopy, 466 negative by microscopy).
  - Provenance: Not explicitly stated regarding country of origin; the study was conducted at "six geographically diverse laboratories" (implying multiple sites within a country or potentially internationally), and data was retrospective (compared to microscopy, which would have been performed on collected samples).
- Percent Agreement Study (Comparison with Predicate):
  - Total Samples: 146 (30 positive for Cryptosporidium by microscopy, 116 negative by microscopy).
  - Provenance: Not explicitly stated regarding country of origin or retrospective/prospective nature.
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- The ground truth for the test set was established by microscopy. The document does not specify the number of experts (e.g., microscopists) involved in reading these slides or their qualifications. It's common in diagnostic studies for the comparator method (like microscopy) to be performed by qualified laboratory personnel, but this detail is not provided.
Adjudication method for the test set:
- The document does not specify any formal adjudication method for the microscopy results that served as the ground truth. It simply states the comparison was "to microscopy."
If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:
- No, an MRMC comparative effectiveness study was not done. This device is a standalone in vitro diagnostic (IVD) lateral flow assay, not an AI or imaging device designed to assist human readers.
If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- Yes, this was a standalone performance study. The Xpect™ Cryptosporidium Lateral Flow Assay is an "algorithm-only" in the sense that it provides a direct qualitative result (presence/absence of a line) without human interpretation beyond reading the line. The presented sensitivity and specificity values represent the performance of the device itself.
The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- The primary ground truth used was microscopy (specifically, for detection of Cryptosporidium).
The sample size for the training set:
- The document does not provide information regarding a separate training set for algorithm development. As this is a lateral flow immunoassay, not an AI or machine learning model, a distinct "training set" in the context of data-driven algorithm development is typically not applicable. The assay's performance characteristics are inherent to its design and manufacturing.
How the ground truth for the training set was established:
- As there's no explicit mention of a training set in the context of algorithm development, this information is not applicable to this device. Early development and optimization of the assay would involve various characterized positive and negative samples, but these are not typically referred to as a "training set" in the same way as for AI.

Summary

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Lenexa, KS 66215

510(k) Notification Xpect™ Cryptosporidium Lateral Flow Assay

KO31965

510(k) Summary

The 510(k) summary is being submitted in accordance with the requirements of SMDA 1990 and 21 CFR §807.92.

Submitter's Identification:

Submitter's Name and Address:

Remel Inc. 12076 Santa Fe Drive Lenexa, KS 66215 (913) 895-4185

Contact: 1) Richard L. Tyson, Ph.D. Director Product Development and Support Ramsey Operations (763) 712-2347 rtyson@remel.com

Earleen C. Parks 2) Regulatory Affairs Manager Lenexa, KS (913) 895-4185 eparks@remel.com
Date Summary Prepared: November 7, 2003

Device Trade Name:

Xpect™ Cryptosporidium Lateral Flow Assay

Predicate Device:

Becton Dickinson ColorPAC™ Giardia/Cryptosporidium Rapid Assay, (k)983399.

Classification Name:

Entamoeba histolytica serological reagents. Cryptosporidium SPP 866.3220 Code: MHJ

Intended Use:

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Device Description:

Comparison with Predicate Device:

The following information supports the Statement of Equivalence between the Becton Dickinson ColorPAC™ Giardia/Cryptosporidium Rapid Assay and the Xpect™ Cryptosporidium Lateral Flow Assay. The differences in technology do not raise additional concerns regarding safety and effectiveness. Safety and effectiveness are demonstrated to be substantially equivalent.

ProductFeature	Becton Dickinson ColorPAC™Giardia/Cryptosporidium Rapid Assay	Xpect™ Cryptosporidium LateralFlow Assay
IntendedUse	Detection of Giardia and Cryptosporidiumantigens in aqueous extracts of fecalspecimens	Detection of Cryptosporidium specificantigen in fecal specimens
Technology	Qualitative immunochromatographic assay	Qualitative immunochromatographic assay
CaptureAntibodiesorMolecules:Device	Mouse anti-Cryptosporidium, goat anti-mouse IgG, Avidin derivative	Rabbit anti-Cryptosporidium, goat anti-mouse IgG
Antibodies:Conjugate	Rabbit anti-Giardia, monoclonal anti-Giardiaand Cryptosporidium	Monoclonal anti-Cryptosporidium
Material:Membrane	Nitrocellulose	Mylar-backed nitrocellulose
Material:Conjugate	Colloidal dye labeled monoclonal antibodiesto Giardia and Cryptosporidium	Anti-mouse and anti-Cryptosporidiumcolored microparticles diluted in buffer
SpecimenType	Human stool preserved in 10% formalin,SAF, MIF or Cary-Blair	Human stool preserved in 10% formalin,SAF or Cary-Blair
Samplevolume	50μl	100μl

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Specimen Stability:

· Fresh, untreated stool specimens should be stored at 2-8°C and tested within 48 hours of collection. If fresh specimens cannot be tested within 48 hours, they should be frozen at -20℃ or below in a non-defrosting freezer and tested within 2 months of collection. Avoid multiple freeze-thaw cycles.
Stool specimens treated with 10% formalin or SAF fixatives may be . refrigerated at 2-8°C or stored at room temperature (20-25°C) and should be tested within 2 months of collection.
. Stool specimens collected in modified Cary Blair Transport Medium with indicator (or equivalent) should be refrigerated and tested within 1 week of collection or frozen (as above) and tested within 2 months of collection. Avoid multiple freeze-thaw cycles.
Stool specimens that have been concentrated or treated with PVA fixatives are . not suitable for use with this test.

Sensitivity/Specificity:

The performance of the Xpect™ Cryptosporidium was evaluated at six geographically diverse laboratories. The overall sensitivity and specificity of the test were compared to microscopy. Performance relative to patients' clinical status has not been established. The overall sensitivity and specificity for Cryptosporidium are listed below.

Cryptosporidium	Microscopy
	+	-
XpectTM	+	108	8
	-	4	458
	Total	112	466

Sensitivity: 96.4% (108/112); 95% CI = 91.2-98.6% Specificity: 98.3% (458/466); 95% CI = 96.6-99.1% Note : CI = Confidence Interval

Percent Agreement:

The Xpect™ Cryptosporidium and a commercially available lateral flow test (the "Predicate Device") were compared side-by-side to microscopy. The Percent Agreement of each assay versus microscopy was as follows:

Cryptosporidium		Microscopy
	+	-
XpectTM	+	28	6
	-	2	110	Agreement
	Total	30	116	94.5% (138/146)
	+	29	21
Predicate	-	1	95	Agreement
	Total	30	116	84.9% (124/146)

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Cross-reactivity:

No cross-reactivity was observed using samples containing the following organisms: Ascaris lumbricoides, Blastocystis hominis, Campylobacter coli, Campylobacter jejuni, Candida albicans, Chilomastix mesnili, Cyclospora cayetanensis, Dientamoeba fragilis, Endolimax nana, Entamoeba coli, Entamoeba hartmanni, Entamoeba histolytica, Enterobius vermicularis, Escherichia coli, Giardia lamblia, hookworm, Hymenolepis nana, lodamoeba bütschlii, Isospora sp., Microsporidia, Rotavirus, Salmonella choleraesuis subsp. choleraesuis serotype Typhimurium, Shigella dysenteriae, Shigella flexneri, Shigella sonnei, Strongyloides stercoralis, Taenia sp., and Trichuris trichiura. Cross-reactivity to Astrovirus and Caliciviruses has not been established.

Interfering Substances:

Prior to testing, positive and negative samples were spiked (20% v/v) with blood, mucin, fecal fat or the following over-the-counter anti-diarrheal products: Pepto-Bismol®, Imodium® A-D, and Kaopectate® (active ingredients: bismuth subsalicylate, loperamide HCl, and attapugite respectively). Testing indicated that none of these substances interfered with the expected result except for Imodium® A-D. Imodium® A-D at 20% (v/v) in stool interfered with the detection of low levels of Cryptosporidium antigen.

Reproducibility :

Reproducibility testing was conducted at seven sites, including one in-house site, on three separate days with ten blinded samples of varying activity. 100% of the 630 samples tested for Cryptosporidium produced the expected result.

Conclusion:

Overall, the results from the clinical and POL investigation demonstrate that the Xpect™ Cryptosporidium Lateral Flow Assay is substantially equivalent to microscopic examination and the Becton Dickinson ColorPAC™ Giardia/Cryptosporidium Rapid Assay when used in accordance with the proposed labeling.

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Public Health Service

Image /page/4/Picture/2 description: The image is a black and white logo for the Department of Health & Human Services (USA). The logo is circular, with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES (USA)" arranged around the top half of the circle. Inside the circle is a stylized image of an eagle, with its wings spread and its head turned to the left.

NOV 1 4 2003

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

Richard L. Tyson, Ph.D. Director Product Development and Support Remel Inc. 12076 Santa Fe Drive Lenexa, KS 66215

Re: K031965

Trade/Device Name: Xpect™ Cryptosporidium Regulation Number: 21 CFR 866.3220 Regulation Name: Entamoeba Histolytica Serological Reagents Regulatory Class: Class II Product Code: MHJ Dated: October 14, 2003 Received: October 16, 2003

Dear Dr. Tyson:

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 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). 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. Iisting of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If vour 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 that FDA has made a determination that your device complies with other requirements of the Act or anv 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); 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) 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 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 (301) 594-3084. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). Other general information on your responsibilities under the Act may be obtained from the Division 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/dsma/dsmamain.html.

Sincerely yours,

Steven Sutman

Steven I. Gutman, M.D., M.B.A. Director Office of In Vitro Diagnostic Device Evaluation and Safety Center for Devices and Radiological Health

Enclosure

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INDICATIONS FOR USE

K031965 510(k) Number (if known):

Xpect™ Cryptosporidium Device Name:

Indications For Use: REMEL's Xpect™ Cryptosporidium kit is an in vitro qualitative immunoassay for the detection of Cryptosporidium antigens in preserved and unpreserved fecal specimens. This test is intended as an aid in the laboratory diagnosis of suspected Cryptosporidium infections.

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

Concurrence Of CDRH, Office of Device Evaluation (ODE)

Ledali H. Carlo

Division Sign-Off

Prescription Use (Per 21 CFR 801.109)

OR Over-The-Counter Use _ Office of In Vitro Diagnostic Device Evaluation and Safety

510(k) K031965

Regulation Number and Section

§ 866.3220

Entamoeba histolytica serological reagents.(a)
Identification. Entamoeba histolytica serological reagents are devices that consist of antigens and antisera used in serological tests to identify antibodies toEntamoeba histolytica in serum. Additionally, some of these reagents consist of antisera conjugated with a fluorescent dye (immunofluorescent reagents) used to identifyEntamoeba histolytica directly from clinical specimens. The identification aids in the diagnosis of amebiasis caused by the microscopic protozoan parasiteEntamoeba histolytica and provides epidemiological information on diseases caused by this parasite. The parasite may invade the skin, liver, intestines, lungs, and diaphragm, causing disease conditions such as indolent ulcers, an amebic hepatitis, amebic dysentery, and pulmonary lesions.(b)
Classification. Class II (special controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to § 866.9.