HEMOSURE ONE-STEP FECAL OCCULT BLOOD TEST

K041202 · W.H.P.M., Inc. · KHE · Aug 12, 2004 · Hematology

Device Facts

• Record ID: K041202
• Device Name: HEMOSURE ONE-STEP FECAL OCCULT BLOOD TEST
• Applicant: W.H.P.M., Inc.
• Product Code: KHE · Hematology
• Decision Date: Aug 12, 2004
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 864.6550
• Device Class: Class 2

Indications for Use

The Hemosure™ One-Step Fecal Occult Blood (FOB) Test is an immunochemical device intended for the qualitative detection of Fecal Occult Blood by laboratories or physicians offices. It is useful to determine gastrointestinal (GI) bleeding found in a number of GI disorders, e.g. diverticulitis, colitis, polyps, and colorectal cancer.

Device Story

The Hemosure™ One-Step FOB Test is a lateral flow sandwich immunoassay used in clinical laboratories or physician offices to detect human hemoglobin (hHb) in fecal samples. The device consists of a test cassette and a fecal collection tube containing extraction buffer. The user collects a fecal sample, mixes it with the buffer, and applies the extract to the test cassette. The device utilizes monoclonal and polyclonal antibodies conjugated to colloidal gold to capture hHb as the sample migrates via capillary action. A positive result is indicated by a pink-rose color band at the test line (hHb ≥50 ng/mL), while a control line confirms proper reagent function. The test provides a qualitative result that aids healthcare providers in identifying potential gastrointestinal bleeding, facilitating further diagnostic investigation for conditions like colorectal cancer or polyps.

Clinical Evidence

Bench testing using 150 spiked stool samples (50 in initial study, 100 in multi-site study). Sensitivity established at 50 ng hHb/mL. Multi-site evaluation (physician office, reference lab, manufacturer lab) showed 97-99% agreement with expected results; overall accuracy 98%. No cross-reactivity with non-human hemoglobin or common dietary/toilet substances.

Technological Characteristics

Lateral flow sandwich immunoassay. Components: nitrocellulose strip, mouse anti-hHb antibodies conjugated to colloidal gold, test line (anti-hHb antibodies), control line (goat anti-mouse IgG). Sensitivity: 50 ng hHb/mL. Format: Cassette. Qualitative visual readout (pink-rose band).

Indications for Use

Indicated for the qualitative determination of fecal occult blood to assist in the detection of gastrointestinal bleeding associated with disorders such as diverticulitis, colitis, polyps, and colorectal cancer.

Regulatory Classification

Identification

An occult blood test is a device used to detect occult blood in urine or feces. (Occult blood is blood present in such small quantities that it can be detected only by chemical tests of suspected material, or by microscopic or spectroscopic examination.)

Special Controls

*Classification.* Class II (special controls). A control intended for use with an occult blood test is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 864.9.

Predicate Devices

• Instant-View Fecal Occult Blood (FOB) II Test (Cassette) (Alfa Scientific Designs, Inc.)

Submission Summary (Full Text)

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

A. 510(k) Number:
K041202

B. Purpose for Submission:
New Device

C. Analyte:
Fecal Occult Blood (FOB)

D. Type of Test:
Qualitative

E. Applicant:
WHPM, Inc.

F. Proprietary and Established Names:
Hemosure™ One-Step Fecal Occult Blood (FOB) Test; Occult Blood Test

G. Regulatory Information:
1. Regulation section:
CFR Section 864.6550 – Occult Blood Test
2. Classification:
Class II
3. Product Code:
KHE
4. Panel:
Hematology (81)

H. Intended Use:
1. Intended use(s):
The Hemosure™ One-Step FOB Test is a rapid, immunochemical device for in vitro diagnostic use in qualitative determination of fecal occult blood by laboratories or physician’s offices.
2. Indication(s) for use:
Same as above; and it is useful to determine gastrointestinal (GI) bleeding found in a number of GI disorders, e.g., diverticulitis, colitis, polyps and colorectal cancer.
3. Special condition for use statement(s):
N/A

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4. Special instrument Requirements: N/A

I. Device Description:
The Hemosure™ One-Step FOB Test is a sandwich immunoassay; and employs a combination of monoclonal and polyclonal antibodies (MAB and PAB) to selectively identify human hemoglobin (hHb) in test samples with a high degree of sensitivity. It consists of a:
- Test Cassette, individually sealed in a foil pouch, containing a combination of mouse MAB and sheep or goat PAB, directed against human hemoglobin (hHb); and
- Fecal Collection Tube of extraction buffer, 2.0 mL.

J. Substantial Equivalence Information:
1. Predicate device name(s): Alfa Scientific Designs, Inc. Instant-View FOB (II) Test
2. Predicate K number(s): #K021423
3. Comparison with predicate:

| Similarities | | |
| --- | --- | --- |
| Item | Device | Predicate |
| Test type | One-step sandwich immu - noassay | Same |
| Antibodies (poly-clonal and mono-clonal) | Anti-human hemoglobin; and goat anti-mouse IgG | Same |
| Sample type | Feces | Same |
| Sensitivity | 50 ng hHb/mL | Same |
| Test window | 5 – 10 minutes | Same |
| Format | Cassette | Same |
| Differences | | |
| Item | Device | Predicate |
| Number of tests/kit | (1) test | (20) tests |
| Indicator color | Pink-rose | Burgundy |

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

## L. Test Principle:

The test cassette consists of a pad containing mouse anti-hHb antibodies conjugated to colloidal gold; a nitrocellulose strip containing a test line (anti-hHb antibodies); and a control line of goat anti-mouse IgG antibodies. As the test sample flows or migrates, via capillary action, through the absorbent test strip, a labeled antibody-dye conjugate binds to human hemoglobin (hHb) in the specimen. An antibody-antigen complex forms, binds to the anti-hHb antibody in the positive test reaction zone, and produces a pink-rose color band for hHb ≥50 ng/mL. In the absence of hHb, no line is produced in the positive test reaction zone. The control line binds the conjugated mouse antibodies regardless of the hHb concentration. A pink-rose color in the control reaction zone demonstrates that the device and reagents are functioning correctly.

## M. Performance Characteristics (if/when applicable):

### 1. Analytical performance:

a. **Precision/Reproducibility:**

Samples (N=100) spiked with varying levels of hHb, ranging from 0 – 2000 ng/mL, were tested, at (3) sites, with (3) lots of tests. At the 50 ng hHb/mL cut-off, Lot 1 yielded (3) false (-) results; and Lots 2 and 3 yielded (1) false (-) result.

b. **Linearity/assay reportable range:**

No prozone effect was seen up to 2000 ng hHb/mL

c. **Traceability (controls, calibrators, or method):**

Mouse monoclonal and polyclonal anti-human hemoglobin antibodies

d. **Detection limit:**

A limit of 50 ng hHb/mL buffer or 50 ug hHb/g feces was determined using samples (N=50), spiked with levels of hHb that ranged 0 2000 ng hHb/ml. They were tested in-house with the proposed and predicate devices. There was agreement of > 99%.

e. **Analytical specificity:**

Interference testing was performed on aqueous samples with and without 50 ng hHb/mL. Substances tested included aqueous extracts of fruits and vegetables; 20 mg/mL solution of horseradish peroxidase; and toilet water with cleaner and deodorizer. Cross reactivity was tested on (9) species of animal hemoglobins, using diluted human fecal samples. No false results were obtained.

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f. Assay cut-off: 50 ng hHb/mL buffer

2. Comparison studies:

a. Method comparison with predicate device: Three lots of the Hemosure and (1) lot of the Alfa assay were tested, in-house, on fecal samples (N=50) spiked with hHb to 1, 37.5, 50, 62.5 and 2000 ng hHb/mL. Both devices gave 30 (+) and 20 (-) readings for > 99% agreement.

b. Matrix comparison: N/A

3. Clinical studies:

a. Clinical sensitivity: N/A

b. Clinical specificity: N/A

c. Other clinical supportive data (when a and b are not applicable): The study on samples (N=100) tested in-house, was also performed at (2) independent sites: a POL and a reference lab. The blinded study used (3) test lots. Stool samples were spiked with hHb at 1, 37.5, 50, 62.5 and 2000 ng hHb/mL. Percent (%) agreement ranged from 95 - > 99%, for an overall agreement of 98%.

4. Clinical cut-off: N/A

5. Expected values/Reference range: Negative (<50 ug hHb/g feces)

N. Conclusion: The submitted material in this premarket notification is complete and supports a substantial equivalence decision.