BUHLMANN fCAL ELISA

• K Number: K181012
• Device Name: BUHLMANN fCAL ELISA
• Manufacturer: BUHLMANN Laboratories AG
• Date Cleared: 2018-06-04 ( 48 days)
• Product Code: NXO
• Regulation Number: 866.5180

Intended Use

The BÜHLMANN fCAL® ELISA is an in vitro diagnostic assay intended for the quantitative measurement of fecal calprotectin in human stool. The BÜHLMANN fCAL® ELISA aids in the diagnosis of inflammatory bowel disease (IBD), specifically Crohn's disease (CD) and ulcerative colitis (UC) and aids in the differentiation of IBD from irritable bowel syndrome (IBS) in conjunction with other laboratory and clinical findings.

Device Description

The BÜHLMANN fCAL® ELISA is an enzyme-linked immunosorbent assay (ELISA) performed using patient stool extracts collected without preservatives. Calprotectin within the extract binds to protein specific antibodies coated on the well surface. An enzyme conjugated antibody detects the captured antigen. Incubation of the complex with substrate results in a colored product which reflects the amount of calprotectin in the sample. Quantification of calprotectin concentration is achieved using standard plate readers.

Predicate Devices

K160447

Reference Devices

Not Found

AI/ML (Artificial Intelligence / Machine Learning)

No
The device description and performance studies detail a standard ELISA assay and its analytical and clinical performance metrics, with no mention of AI or ML technologies.

Therapeutic

No
The device is an in vitro diagnostic assay used for quantitative measurement of fecal calprotectin to aid in the diagnosis of inflammatory bowel disease; it does not treat or prevent disease.

Diagnostic

Yes
The "Intended Use / Indications for Use" section explicitly states that the device "aids in the diagnosis of inflammatory bowel disease (IBD)".

SaMD (Software as a Medical Device)

No

The device description clearly outlines a laboratory-based enzyme-linked immunosorbent assay (ELISA) which involves physical reagents, sample processing, and the use of a standard plate reader, 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 "Intended Use / Indications for Use" section explicitly states: "The BÜHLMANN fCAL® ELISA is an in vitro diagnostic assay intended for the quantitative measurement of fecal calprotectin in human stool."

This statement directly identifies the device as an in vitro diagnostic product.

PCCP (Predetermined Change Control Plan) Authorized

N/A

Overview

Intended Use / Indications for Use

The BÜHLMANN fCAL® ELISA is an in vitro diagnostic assay intended for the quantitative measurement of fecal calprotectin in human stool. The BÜHLMANN fCAL® ELISA aids in the diagnosis of inflammatory bowel disease (IBD), specifically Crohn's disease (CD) and ulcerative colitis (UC) and aids in the differentiation of IBD from irritable bowel syndrome (IBS) in conjunction with other laboratory and clinical findings.

Product codes

NXO

Device Description

The BÜHLMANN fCAL® ELISA is an enzyme-linked immunosorbent assay (ELISA) performed using patient stool extracts collected without preservatives. Calprotectin within the extract binds to protein specific antibodies coated on the well surface. An enzyme conjugated antibody detects the captured antigen. Incubation of the complex with substrate results in a colored product which reflects the amount of calprotectin in the sample. Quantification of calprotectin concentration is achieved using standard plate readers.

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 (study type, sample size, AUC, MRMC, standalone performance, key results)

The following performance studies were conducted in support of the substantial equivalence determination:

• establishment of clinical thresholds;
• traceability/standardization; ●
• precision/reproducibility; ●
• linearity; ●
• accuracy/recovery; ●
• interfering substances;
• analytical sensitivity;
• stability (analyte and reagent); and ●
• clinical study.

Clinical Thresholds:

Calprotectin Concentration	Interpretation	Follow-Up
160 µg/g	Elevated	Retest as appropriate

Precision:
Single-Site Repeatability Study Results (n=80 for each sample, 7 samples tested, results in SD and %CV)
Multi-Site Precision Study Results (n=240 for each sample, 5 samples tested, including between-operator and between-site, results in SD and %CV)
Lot-to-Lot Reproducibility Study Results (n=74 or 75 for each sample, 6 samples tested, including between-reader and between-lot, results in SD and %CV)
Extraction Reproducibility Study Results (n=20 for each sample, 6 samples tested, including within-extraction and between-extraction, results in SD and %CV)

Linearity:
Analytical measuring range: 30 – 1800 µg/g.

Accuracy/Recovery:
7 specimen extracts tested with mean baseline, expected post-spike, observed post-spike, and recovery rate ranging from 96.4% to 102.2%.

Analytical Sensitivity:
LoB = 8.3 µg/g (mg/kg)
LoD = 12.6 µg/g (mg/kg)
LoQ = 30 µg/g (mg/kg)

Interfering Substances:
Tested analytes, pharmaceuticals, and nutritional supplements (gyno-Tardyferon, Prednisone, Imurek, Salofalk, Agopton, Asacol, Vancocin, Sulfamethoxazole, Trimethoprim, Ciproxine, Vitamin E, Bion 3, Hemoglobin) did not interfere when added to stool extracts at given concentrations.
Tested microorganisms (Escherichia coli, Salmonella enterica subsp. enterica, Klebsiella pneumoniae subsp. pneumonia, Citrobacter freundii, Shigella flexneri, Yersinia enterocolitica subsp. enterocolitica) did not interfere when added to stool extracts at given cell counts.

Clinical Study (Clinical Sensitivity/Specificity of IBD vs. non-IBD):
Total N=337 patients.

• Borderline values considered Positive:
  Sensitivity = 93.3%; 95% C.I. (87.7%, 96.9%)
  Specificity = 70.3%; 95% C.I. (63.5%, 76.5%)
  PPV = 67.7%; 95% C.I. (60.5%, 74.4%)
  NPV = 94.0%; 95% C.I. (89.0%, 97.2%)
• Borderline values considered Negative:
  Sensitivity = 84.4%; 95% C.I. (77.2%, 90.1%)
  Specificity = 83.7%; 95% C.I. (77.8%, 88.5%)
  PPV = 77.6%; 95% C.I. (69.9%, 84.0%)
  NPV = 88.9%; 95% C.I. (83.6%, 93.0%)

Clinical Study (Clinical Sensitivity/Specificity of IBD vs. IBS):
Total N=265 patients.

• Borderline values considered Positive:
  Sensitivity = 93.3%; 95% C.I. (87.7%, 96.9%)
  Specificity = 72.3%; 95% C.I. (63.8%, 79.8%)
  PPV = 77.8%; 95% C.I. (70.6%, 83.9%)
  NPV = 91.3%; 95% C.I. (84.1%, 95.9%)
• Borderline values considered Negative:
  Sensitivity = 84.4%; 95% C.I. (77.2%, 90.1%)
  Specificity = 85.4%; 95% C.I. (78.1%, 91.0%)
  PPV = 85.7%; 95% C.I. (78.6%, 91.2%)
  NPV = 84.1%; 95% C.I. (76.7%, 89.9%)

Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)

See "Summary of Performance Studies" for detailed metrics.

Predicate Device(s)

K160447

Reference Device(s)

Not Found

Predetermined Change Control Plan (PCCP) - All Relevant Information

Not Found

Regulation Number and Section

§ 866.5180 Fecal calprotectin immunological test system.

(a)
Identification. A fecal calprotectin immunological test system is anin vitro diagnostic device that consists of reagents used to quantitatively measure, by immunochemical techniques, fecal calprotectin in human stool specimens. The device is intended forin vitro diagnostic use as an aid in the diagnosis of inflammatory bowel diseases (IBD), specifically Crohn's disease and ulcerative colitis, and as an aid in differentiation of IBD from irritable bowel syndrome.(b)
Classification. Class II (special controls). The special control for these devices is FDA's guidance document entitled “Class II Special Controls Guidance Document: Fecal Calprotectin Immunological Test Systems.” For the availability of this guidance document, see § 866.1(e).

Summary

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June 4, 2018

BUHLMANN Laboratories AG Roshana Ahmed Associate Director, Regulatory Affairs Mapi SRS, an ICON plc Company 2343 Alexandria Drive Suite 100 Lexington, Kentucky 40504

Re: K181012

Trade/Device Name: BUHLMANN fCAL ELISA Regulation Number: 21 CFR 866.5180 Regulation Name: Fecal calprotectin immunological test system Regulatory Class: Class II Product Code: NXO Dated: April 16, 2018 Received: April 17, 2018

Dear Roshana Ahmed:

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, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. 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 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 Part

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801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

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/ReportaProblem/default.htm.

For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/) and CDRH Learn (http://www.fda.gov/Training/CDRHLearn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (http://www.fda.gov/DICE) for more information or contact DICE by email ([e-mail]) or phone [phone] or 301-796-7100).

Sincerely,

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For

Lea Carrington, Director Division of Immunology and Hematology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K181012

Device Name BUHLMANN fCAL(R) ELISA

Indications for Use (Describe)

The BÜHLMANN fCAL® ELISA is an in vitro diagnostic assay intended for the quantitative measurement of fecal calprotectin in human stool. The BÜHLMANN fCAL® ELISA aids in the diagnosis of inflammatory bowel disease (IBD), specifically Crohn's disease (CD) and ulcerative colitis (UC) and aids in the differentiation of IBD from irritable bowel syndrome (IBS) in conjunction with other laboratory and clinical findings.

Type of Use (Select one or both, as applicable)

Prescription Use (Part 21 CFR 801 Subpart D)
Over-The-Counter Use (21 CFR 801 Subpart C)

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510(k) Summary

I. Submitter

BÜHLMANN Laboratories AG Baselstrasse 55 Schönenbuch CH-4124 Switzerland Phone: [phone]

Contact Person: Alicja Ritz, Ph.D., Head Regulatory Affairs Date Prepared: May 22, 2018

II. Device

Device Proprietary Name:	BÜHLMANN fCAL® ELISA
Common or Usual Name:	Fecal calprotectin immunological test system
Classification Name:	Calprotectin, Fecal
Regulation Number:	21 CFR 866.5180
Product Code:	NXO
Device Classification	II

III. Predicate Device

Substantial equivalence is claimed to the following device:

• Calprest®NG, K160447, Eurospital S.p.A. ●

IV. Device Description

The BÜHLMANN fCAL® ELISA is an enzyme-linked immunosorbent assay (ELISA) performed using patient stool extracts collected without preservatives. Calprotectin within the extract binds to protein specific antibodies coated on the well surface. An enzyme conjugated antibody detects the captured antigen. Incubation of the complex with substrate results in a colored product which reflects the amount of calprotectin in the sample. Quantification of calprotectin concentration is achieved using standard plate readers.

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V. Indications for Use

The BÜHLMANN fCAL® ELISA is an in vitro diagnostic assay intended for the quantitative measurement of fecal calprotectin in human stool. The BÜHLMANN fCAL® ELISA aids in the diagnosis of inflammatory bowel disease (IBD), specifically Crohn's disease (CD) and ulcerative colitis (UC) and aids in the differentiation of IBD from irritable bowel syndrome (IBS) in conjunction with other laboratory and clinical findings.

VI. Comparison of Technological Characteristics

The BÜHLMANN fCAL® ELISA and the Calprest®NG share the following characteristics:

• use of ELISA technology to detect calprotectin in stool samples; ●
• use of quantitative assay format;
• use of 96 well microtiter plate;
• use of TMB as substrate; and ●
• optical density reading at 450 nm.

The BÜHLMANN fCAL® ELISA is technologically different from the Calprest®NG as follows:

• . use of different sample extraction buffers and sample dilution;
• use of different antibodies for microtiter plate coating;
• use of different detection antibodies; ●
• use of different calibrator concentrations; ●
• use of a different standardization;
• different clinical thresholds; and
• . different reportable ranges.

The tables below compares key technological features between the subject and predicate devices.

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Technological comparison

BÜHLMANN fCAL® ELISA Reagents

Similarities
Parameter	BÜHLMANN fCAL® ELISA	Calprest®NG
(K160447)
Method	Colorimetric ELISA	Colorimetric ELISA
Analyte	Calprotectin	Calprotectin
Assay Format	Quantitative	Quantitative
Sample Type	Fecal	Fecal
Platform	96-well microtiter plate	96-well microtiter plate
Conjugate	HRP Horse Radish Peroxidase	HRP Horse Radish Peroxidase
Substrate	TMB	TMB
OD Reading	450 nm	450 nm

Differences
Parameter	BÜHLMANN fCAL® ELISA	Calprest®NG
(K160447)
Reportable Range	30 - 1800 µg/g (mg/kg)	27.1 – 3000 mg/kg
Sample Volume	160 µg/g	Normal: 120 mg/kg (µg/g)

BÜHLMANN fCAL® ELISA Controls

| Parameter | BÜHLMANN fCAL® ELISA | Calprest®NG
(K160447) |
|------------------------------------|---------------------------|-------------------------------------------|
| Method | BÜHLMANN fCAL® ELISA | Calprest®NG |
| Analyte | Native human calprotectin | Recombinant calprotectin antigen
(rAg) |
| Levels | 2 (high and low) | 2 (high and low) |
| Physio-chemical
characteristics | Ready to use | Ready to use |

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| Parameter | BÜHLMANN fCAL® ELISA | Calprest®NG
(K160447) |
|-------------------|--------------------------------------------|-----------------------------------------------------|
| Method | BÜHLMANN fCAL® ELISA | Calprest®NG |
| Analyte | Native human calprotectin | Recombinant calprotectin antigen
(rAg) |
| Calibrators | 5 levels:
4, 12, 40, 120, and 240 ng/mL | 6 levels:
0, 2.5, 12.5, 25, 50, and 150
ng/mL |
| Conversion factor | 7.5 | 20 |
| Nominal Value | | 0 |
| Assignment | 30 µg/g
90 µg/g | 50 µg/g
250 µg/g |
| | 300 µg/g
900 µg/g | 500 µg/g
1000 µg/g |
| | 1800 µg/g | 3000 µg/g |

BÜHLMANN fCAL® ELISA Calibrators

Discussion

As seen above, the differences between the subject and predicate devices include the use of different sample extraction buffers and dilution ratios, use of different antibodies and calibrator concentrations, and use of different cut-offs. These differences are addressed by the performance data identified below.

VII. Summary of Performance Characteristics

The following performance studies were conducted in support of the substantial equivalence determination:

• establishment of clinical thresholds;
• traceability/standardization; ●
• precision/reproducibility; ●
• linearity; ●
• accuracy/recovery; ●
• interfering substances;
• analytical sensitivity;
• stability (analyte and reagent); and ●
• clinical study.

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A. Clinical Thresholds

Calprotectin Concentration	Interpretation	Follow-Up
160 µg/g	Elevated	Retest as appropriate

B. Precision

Single-Site Repeatability Study Results

| Sample | Mean | n | Within-run
(Repeatability) | | Between-run | | Between-day | | Total
(Within-Laboratory) | |
|--------|-------|----|-------------------------------|------|-------------|------|-------------|------|------------------------------|------|
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| P1 | 38.5 | 80 | 2.3 | 5.8% | 1.8 | 4.8% | 2.2 | 5.6% | 3.6 | 9.4% |
| P2 | 67.0 | 80 | 2.0 | 3.0% | 3.5 | 5.2% | 1.6 | 2.4% | 4.3 | 6.4% |
| P3 | 135.7 | 80 | 2.3 | 1.7% | 5.6 | 4.1% | 0 | 0% | 6.0 | 4.4% |
| P4 | 207.1 | 80 | 4.1 | 2.0% | 12.5 | 6.0% | 0 | 0% | 13.2 | 6.4% |
| P5 | 337.1 | 80 | 5.9 | 1.8% | 18.3 | 5.4% | 0 | 0% | 19.3 | 5.7% |
| P6 | 562.6 | 80 | 11.0 | 2.0% | 13.6 | 2.4% | 2.5 | 0.4% | 17.7 | 3.1% |
| P7 | 918.0 | 80 | 18.6 | 2.0% | 62.1 | 6.8% | 20.8 | 2.3% | 68.1 | 7.4% |

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Sample	Mean	n	Within-run		Between-run		Between-day		Between-operator		Between-site		Total
			SD	%CV	SD	%CV	SD	%CV	SD	%CV	SD	%CV	SD	%CV
S01	41.4	240	3.1	7.4%	8.1	19.6%	0.0	0.0%	0.0	0.0%	4.1	9.9%	9.6	23.2%
S02	67.2	240	3.0	4.4%	7.0	10.4%	0.0	0.0%	1.9	2.8%	3.9	5.8%	8.8	13.0%
S03	143.0	240	5.6	3.9%	15.7	11.0%	0.0	0.0%	2.6	1.8%	3.7	2.6%	17.3	12.1%
S04	379.8	240	10.8	2.9%	16.4	4.3%	3.2	0.9%	0.0	0.0%	13.7	3.6%	24.2	6.4%
S05	1056.6	240	40.1	3.8%	53.8	5.1%	0.0	0.0%	39.6	3.7%	67.6	6.4%	103.1	9.8%

Multi-Site Precision Study Results

Lot-to-Lot Reproducibility Study Results

| Sample | Mean
(µg/g) | n | Within-run | | Between-day | | Between-reader | | Between-operator | | Between-lot | | Total | |
|--------|----------------|----|--------------|------|--------------|------|----------------|------|------------------|------|--------------|------|--------------|------|
| | | | SD
(µg/g) | %CV | SD
(µg/g) | %CV | SD
(µg/g) | %CV | SD
(µg/g) | %CV | SD
(µg/g) | %CV | SD
(µg/g) | %CV |
| 2 | 46.4 | 74 | 2.5 | 5.5% | 0.5 | 1.1% | 2.3 | 5.0% | 1.5 | 3.2% | 2.4 | 5.3% | 4.5 | 9.7% |
| 3 | 105.5 | 75 | 2.5 | 2.4% | 1.4 | 1.4% | 2.6 | 2.4% | 0.8 | 0.8% | 2.1 | 2.0% | 4.5 | 4.2% |
| 4 | 133.6 | 75 | 5.0 | 3.8% | 1.9 | 1.4% | 2.2 | 1.7% | 0.0 | 0.0% | 4.2 | 3.2% | 7.2 | 5.4% |
| 5 | 178.5 | 75 | 6.3 | 3.5% | 0.0 | 0.0% | 0.7 | 0.4% | 2.3 | 1.3% | 6.3 | 3.5% | 9.2 | 5.2% |
| 6 | 435.2 | 75 | 12.4 | 2.9% | 7.5 | 1.7% | 0.0 | 0.0% | 0.0 | 0.0% | 18.1 | 4.2% | 23.2 | 5.3% |
| 7 | 1476.1 | 75 | 48.4 | 3.3% | 88.6 | 6.0% | 0.0 | 0.0% | 32.2 | 2.2% | 31.4 | 2.1% | 110.6 | 7.5% |

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| Sample | Mean
(µg/g) | n | Within-extraction | | Between-extraction | | Total | |
|--------|----------------|----|-------------------|-------|--------------------|-------|--------------|-------|
| | | | SD
(µg/g) | %CV | SD
(µg/g) | %CV | SD
(µg/g) | %CV |
| | | | S01 | 51.2 | 20 | 4.5 | 8.9% | 7.8 |
| S03 | 88.3 | 20 | 6.6 | 7.5% | 13.3 | 15.0% | 14.8 | 16.8% |
| S05 | 66.8 | 20 | 10.6 | 15.8% | 3.7 | 5.5% | 11.2 | 16.7% |
| S06 | 179.3 | 20 | 16.8 | 9.4% | 32.8 | 18.3% | 36.8 | 20.5% |
| S07 | 366.1 | 20 | 22.4 | 6.1% | 32.3 | 8.8% | 39.3 | 10.7% |
| S08 | 327.4 | 20 | 15.4 | 4.7% | 26.9 | 8.2% | 31.0 | 9.5% |
| S09 | 1783.7 | 20 | 198.3 | 11.1% | 262.0 | 14.7% | 328.6 | 18.4% |

Extraction Reproducibility Study Results

C. Linearity

Analytical measuring range: 30 – 1800 µg/g.

D. Accuracy/Recovery

| Specimen
Extract | Mean Baseline
Result (µg/g) | Expected Post-
Spike Result (µg/g) | Observed Post-Spike
Result (µg/g) | Recovery
rate (%) |
|---------------------|--------------------------------|---------------------------------------|--------------------------------------|----------------------|
| #1 | 46.5 | 226.5 | 224.5 | 99.1% |
| #2 | 63.7 | 243.7 | 247.7 | 101.6% |
| #3 | 89.0 | 269.0 | 274.9 | 102.2% |
| #4 | 111.6 | 291.6 | 292.0 | 100.1% |
| #5 | 163.5 | 343.5 | 331.1 | 96.4% |
| #6 | 304.0 | 484.0 | 475.0 | 98.1% |
| #7 | 990.2 | 1170.2 | 1166.6 | 99.7% |

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E. Analytical Sensitivity

LoB = 8.3 µg/g (mg/kg) LoD = 12.6 µg/g (mg/kg) LoQ = 30 µg/g (mg/kg)

F. Interfering Substances

Study procedures were performed using the following four (4) stool specimen extracts:

• one extract with calprotectin concentration close to the lower measuring limit of 30 ● ug/g:
• . one extract with calprotectin concentration of approximately 100 µg/g;
• one extract with calprotectin concentration of approximately 200 µg/g; and
• one extract with calprotectin concentration of approximately 500 µg/g.

The following analytes, pharmaceuticals and nutritional supplements did not interfere with the BÜHLMANN fCAL® ELISA when added to stool extracts at the given test concentrations:

| Trade name | Active component | Solvent | Concentration
(mg/mL) |
|------------------|-------------------------|--------------------------------------|--------------------------|
| gyno-Tardyferon | Iron (II) sulfate | HCl / NaOH | 0.04 |
| Prednisone | Prednisone | DMSO | 0.13 |
| Imurek | Azathioprine | DMSO | 0.08 |
| Salofalk | Mesalamine; 5-ASA | DMSO | 2.09 |
| Agopton | Lansoprazole | Dimethylformamide | 0.07 |
| Asacol | Mesalamine; 5-ASA | DMSO | 1.00 |
| Vancocin | Vancomycin | H2Odd | 0.80 |
| Sulfamethoxazole | Sulfamethoxazole | DMSO | 0.64 |
| Trimethoprim | Trimethoprim lactate | DMSO / Exbuffer | 0.14 |
| Ciproxine | Ciprofloxacin | solvent from manufacturer /
H2Odd | 0.50 |
| Vitamin E | DL-a Tocopherol Acetate | H2O+Tween | 0.12 |
| Bion 3 | Multivitamin | HCl / NaOH | 0.43 |
| Hemoglobin | Hemoglobin | H2Odd | 0.50 |

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The following microorganisms did not interfere with the BÜHLMANN fCAL® ELISA when added to stool extracts at the given cell counts:

| Microorganism | Concentration
(cfu/mL) |
|-----------------------------------------------|---------------------------|
| Escherichia coli | $9.5 x 10^7$ |
| Salmonella enterica subsp. enterica | $1 x 10^9$ |
| Klebsiella pneumoniae subsp. pneumonia | $5.4 x 10^7$ |
| Citrobacter freundii | $9.7 x 10^7$ |
| Shigella flexneri | $1.5 x 10^8$ |
| Yersinia enterocolitica subsp. enterocolitica | $1.6 x 10^8$ |

G. Clinical Study (Clinical Sensitivity/Specificity of IBD vs. non-IBD)

Borderline Values		IBD
considered Positive		Positive	Negative	Total
BÜHLMANN	Positive	126	60	186
fCAL®	Negative	9	142	151
ELISA	Total	135	202	337
Sensitivity = 93.3%; 95% C.I. (87.7%, 96.9%)
Specificity = 70.3%; 95% C.I. (63.5%, 76.5%)
PPV = 67.7%; 95% C.I. (60.5%, 74.4%)
NPV = 94.0%; 95% C.I. (89.0%, 97.2%)

Borderline Values		IBD
considered Negative		Positive	Negative	Total
BÜHLMANN Positive		114	33	147
fCAL®	Negative	21	। ਉਹ	190
ELISA	Total	ા રેર	202	337
Sensitivity = 84.4%; 95% C.I. (77.2%, 90.1%)
Specificity = 83.7%; 95% C.I. (77.8%, 88.5%)
PPV = 77.6%; 95% C.I. (69.9%, 84.0%)
NPV = 88.9%; 95% C.I. (83.6%, 93.0%)

12

| Borderline Values

considered Positive		Clinical Diagnosis		Total
		IBD	IBS
BÜHLMANN
fCAL®
ELISA	Positive	126	36	162
	Negative	9	94	103
	Total	135	130	265
Sensitivity = 93.3%; 95% C.I. (87.7%, 96.9%)
Specificity = 72.3%; 95% C.I. (63.8%, 79.8%)
PPV = 77.8%; 95% C.I. (70.6%, 83.9%)
NPV = 91.3%; 95% C.I. (84.1%, 95.9%)

H. Clinical Study (Clinical Sensitivity/Specificity of IBD vs. IBS)

Borderline Values		Clinical Diagnosis
considered Negative		IBD	IBS	Total
BÜHLMANN Positive		114	19	133
fCAL®	Negative	21	111	132
ELISA	Total	ા રેર	130	265
Sensitivity = 84.4%; 95% C.I. (77.2%, 90.1%)
Specificity = 85.4%; 95% C.I. (78.1%, 91.0%)
PPV = 85.7%; 95% C.I. (78.6%, 91.2%)
NPV = 84.1%; 95% C.I. (76.7%, 89.9%)

VIII. Conclusion

The information provided above supports that the BÜHLMANN fCAL® ELISA is as safe and effective as the predicate devices. Although technological differences exist between the subject and predicate devices, performance testing supports that these differences do not raise any new questions of safety and effectiveness. Therefore, it is concluded that the BÜHLMANN fCAL® ELISA is substantially equivalent to the predicate devices.

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