The BioGenex Mouse Monoclonal Anti-Estrogen Receptor Antibody (Clone ER88) is an immunohistochemical (IHC) assay and is intended for laboratory use to qualitatively identify by light microscopy human estrogen receptor in normal and/or pathological paraffin-embedded, formalin-fixed tissues. The ER88 antibody specifically binds to antigens located in the nucleus of cell populations that express estrogen receptor in normal and abnormal tissues. This antibody is indicated as an aid in assessing patient response to hormonal therapy and as an aid in the prognosis and management of breast cancer patients. The clinical interpretation of any staining or its absence should be complemented by morphological studies using proper controls and should be evaluated within the context of the patient's clinical history and other diagnostic tests by a qualified pathologist.

Device Description

BioGenex ER88 is a monoclonal antibody, which specifically binds to estrogen receptor antigen located in the nuclear region of a variety of normal and abnormal tissues. It is a mouse monoclonal anti-estrogen receptor antibody from mouse ascites fluid diluted in phosphate buffered saline pH 7.6 containing bovine serum albumin as carrier protein and 0.09% sodium azide as preservative. The antibody is available in concentrated (MU368-UC) as well as ready to use form (AM368-5M and AM368-10M). Refer to package insert for details.

AI/ML Overview

Here's a breakdown of the acceptance criteria and study detailed in the provided text:

1. Table of Acceptance Criteria and Reported Device Performance:

The document primarily focuses on demonstrating substantial equivalence to existing methods rather than explicit, numerical acceptance criteria for a new AI diagnostic. However, the core performance metric for equivalency is the concordance between the new IHC assay and the established DCC assay.

Acceptance Criteria (Implied)	Reported Device Performance
Substantial equivalence to predicate DCC assay.	Overall binary concordance of ER88 IHC to ER DCC assay was 75%
Confidence interval suggests robust concordance.	95% confidence interval of 68% - 83% (p<0.0001)
Specificity in normal tissues (negative immunoreactivity).	ER88 antibody demonstrated negative immunoreactivity with most normal tissues except mammary gland, myometrium, and endometrium (where positive staining is expected for ER).
Reproducibility (Intra-run, Inter-run, Manual vs. Automated).	No significant variation observed in intra-run, inter-run, and instrumental vs. manual runs.
Stability for intended storage duration.	Stable for at least 24 months at 2-8°C.
Stability under shipping stress (elevated temperature).	Stable after continuous 48-hour exposure at 45°C.
Similarity in technological characteristics to predicate Dako device.	Demonstrated similar clone type, antibody, immunoglobulin class, specificity, total protein concentration, storage, and application (manual/automated use).

2. Sample Size Used for the Test Set and Data Provenance:

Sample Size: 122 specimens.
Data Provenance: The specimens were clinical specimens from two different batches.
- Batch 1 (29 specimens): Assayed for DCC at the University of Texas Health Science Center at San Antonio, Texas. IHC staining was done at King's County Hospital, State University of New York, Health Science Center, Brooklyn, New York.
- Batch 2 (93 specimens): Assayed for DCC at Genesee Hospital, Rochester, NY. Tissue blocks were provided to BioGenex laboratories for slide preparation and IHC staining.
Retrospective/Prospective: The study used existing formalin-fixed and paraffin-embedded tissue sections that had already been assayed for ER by DCC. This indicates a retrospective approach.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications:

Number of Experts: Each resulting slide from the IHC staining was read independently by two pathologists.
Qualifications: The document states "two pathologists, who have no knowledge of any other laboratory or clinical data of the specimens." Specific experience levels (e.g., 10 years of experience) are not provided in this document.

4. Adjudication Method for the Test Set:

The document states that "each resulting slide was read independently by two pathologists." It does not specify an adjudication method like 2+1 or 3+1 if their readings differed. It implies that their independent readings were used to establish the IHC interpretation, which was then compared to the DCC results.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done:

No, a MRMC comparative effectiveness study comparing human readers with AI vs. without AI assistance was not done. This document describes the performance of an immunohistochemical (IHC) assay (an antibody reagent), not an AI-powered diagnostic device. The "device" in this context is the antibody and associated detection system.

6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Was Done:

Not applicable. As stated above, this is about an antibody reagent for IHC, not an AI algorithm. The IHC slides are interpreted by human pathologists. The device itself is a reagent, not an automated interpretation system.

7. The Type of Ground Truth Used:

The primary ground truth used for performance comparison was the dextran-charcoal coated (DCC) assay, which is a biochemical assay considered the "gold standard for ER assay" at the time. Pathologists' readings of the IHC slides were then compared to the DCC results.

8. The Sample Size for the Training Set:

Not explicitly stated or applicable. Since this is a submission for an antibody reagent and not a machine learning model, there isn't a "training set" in the sense of data used to train an AI algorithm. The performance evaluation focuses on the reactivity and concordance of the antibody.

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

Not applicable. See point 8.

Summary

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K013148

FEB 2 8 2002

SUMMARY OF SAFETY AND EFFECTIVENESS INFORMATION

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

GENERAL INFORMATION:

Submitter:	BioGenex Laboratories, Inc.4600 Norris Canyon RoadSan Ramon, CA 94583925-275-0550 (Tel)925-275-0580 (Fax)
Contact Persons:	Gurvinder S. Nanda, Ph.D.Manager, Regulatory Affairs925-543-1336 (Tel)925-866-2525 (Fax)
	Jintao Chen, Ph.D.Director, Operations925-866-2568 (Tel)925-866-2525 (Fax)
Date of Preparation:	January 30, 2002
Device Generic Name:	Mouse Monoclonal Anti-Estrogen Receptor Antibody
Device Trade Name:	BioGenex Mouse Monoclonal Anti-Estrogen ReceptorAntibody (Clone ER88)
Device Classification Name:	Immunohistochemistry Reagents and Kits
Assigned 510(k) Number:	K013148

PREDICATE DEVICE:

The device is substantially equivalent to certain well-established, widely accepted reference laboratory methodology dextran-coated charcoal (DCC) technique which were common in use prior to May 28, 1976. The device is substantially equivalent in methodology to similar kit for estrogen receptor (Dako, K993957).

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DESCRIPTION OF THE DEVICE:

INTENDED USE:

BioGenex ER88 antibodies have been optimally manufactured for use with BioGenex Super Sensitive MultiLink Detection Systems with or without BioGenex Automated Staining Systems.

STATEMENT OF HOW TECHNOLOGICAL CHARACTERISTICS COMPARED TO SUBSTANTIAL EQUIVALENT DEVICE:

A table is provided below comparing the similarities and differences between the BioGenex device and the predicate Dako Device (K993957) to detect estrogen receptors in normal and or pathological tissues.

	BioGenex(New device-K013148)	Dako(Predicate device K993957)
Clone	ER88	1D5
Antibody	Mouse monoclonal	Mouse monoclonal
Immunoglobulin Class	Mouse IgG1, Kappa	Mouse IgG1, Kappa
Intended Use	Is intended for laboratory useto qualitatively identify bylight microscopy humanestrogen receptor in normal	May be used in semiquantitative detection ofhuman estrogen receptor intissue sections of human

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	and/or pathological paraffin-embedded, formalin-fixedtissues.	breast cancer byimmunohistochemistry.
Indication	This antibody is indicated asan aid in assessing patientresponse to hormonal therapyand as an aid in the prognosisand management of breastcancer patients.	This antibody is indicated asan aid in assessing the likelyhood of response to therapyas well as in prognosis andmanagement of breast cancerpatients.
Specificity	Human estrogen receptor informalin-fixed paraffinembedded tissues.	Human estrogen receptor informalin-fixed paraffinembedded tissues.
Total proteinconcentration:	10 mg/ml	10 mg/ml
Storage	2-8°C	2-8°C
Application	For manual and automateduse	For manual and automateduse

PERFORMANCE DATA:

1. Specificity of Primary Antibody

A total of 88 formalin-fixed and paraffin-embedded tissues covering a wide range of normal human tissue types were tested with the BioGenex ER88 antibody using BioGenex Super Sensitive HRP Detection System. In normal human tissues ER88 antibody demonstrated negative immunoreactivity with most tissues. However, positive immunoreactivity was observed with some normal tissues like the nuclei of acini and duct cells of mammary gland and myometrium and endometrium of uterus.

2. Reproducibility

(a) Intra run (within-run) assay: The reproducibility of staining was determined by staining 10 slides of the same tissues within a single run. All slides were stained by the same individual using the same set of reagents for each of the tissues tested. Evaluation of the results indicates no significant variation among the slides of the same tissue stained in the same run.
(b) Inter run (run-to-run) assay: The reproducibility between runs was determined by staining slides containing the same tissues over 10 different runs. Evaluation of the results indicates no significant variation among the slides of the same tissue stained in different runs.
(c) Instrumental runs vs. manual runs: Ten slides each were stained with the antibody manually and using BioGenex Automated Stainer for each of the tissues tested. Tissue blocks were selected to demonstrate reproducibility over a wide

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range of reactivity scale. The prediluted form of ER88 antibody was used for this study along with BioGenex Super Sensitive MultiLink Detection System with DAB as the substrate. Evaluation of the results indicates no significant variation among the slides of the same tissue stained manually and in the automated process.

3. Sensitivity

Comparison between ER88 IHC and reference DCC assays. The study was designed to use independent clinical specimens to establish the performance characteristics of ER88 antibody staining and its concordance with the reference methodology, dextrancharcoal coated (DCC) assay. The DCC assay is a biochemical assay and has been considered the gold standard for ER assay. More recently, immunohistochemistry (IHC) has become a popular method for such testing (Kell, D et al. 1993, Goussard, 1998; Ferrero-Pous, M et al. 2001).

A total of 122 specimens were used in this study. All the specimens were selected according to the following criteria: 1) fomalin-fixed and paraffin-embedded tissue sections were available; 2) each tissue was initially assayed for ER by DCC. No other selection criteria were employed. The study was conducted using two different batches of clinical specimens to include approximately 50% positive and negative cases.

The first batch of 29 specimens was assayed for DCC in the laboratory of the late Dr. William McGuire at the University of Texas Health Science Center at San Antonio, Texas. The DCC results were scored as positive using a cut-off value of ≥10 femtomoles/mg of protein. IHC staining of these slides was done in the laboratory of Dr. Louis P. Pertschuk in the Department of Pathology, King's County Hospital. State University of New York, Health Science Center, Brooklyn, New York using detection reagents provided by BioGenex.

The second batch of 93 specimens was assaved for DCC in the laboratory of Dr. William Fricke (Genesee Hospital, Rochester, NY). The DCC results were scored as positive or negative using a cut-off value of ≥10 femtomoles/mg of protein. The tissue blocks were provided to BioGenex laboratories for slide preparation and IHC staining using BioGenex detection reagents.

For both the studies, each resulting slide was read independently by two pathologists, who have no knowledge of any other laboratory or clinical data of the specimens. The scoring was based on percentage of cells with positive nuclear staining (Fitzgibbons PL, et al, 2000). Any trace of nuclear staining was counted as positive result (NIH Consensus Statement, 2000). The intensity of staining was not factored into the scoring system. A cut-off value of >10% of positive tumor cells was used to score a slide as positive or negative.

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The overall binary concordance of ER88 IHC staining to ER DCC assay was 75% (92/122), with a 2-side 95% confidence interval of 68% - 83% (p<0.0001). This level of concordance indicated that ER88 IHC results and ER DCC results were similar. However, 25% of the results were discordant between these two methods. Reasons for discordance between hormone receptor IHC staining and hormone receptor DCC assays are well known (Kell, et al. 1993; Goussard, 1998; Ferrero-Poüs, et al. 2001), Since DCC requires specimen homogenization, the cellular localization of any detected receptor can not be determined. The receptor might be from either benign epithelium or tumor cells or both sources within the same tissue. With IHC, positive signals from only the tumor areas of the tissue are read by trained pathologists and signals from apparent normal areas from the same tissue are ignored. This would suggest that the IHC method is more specific than the DCC method.

4. Stability:

The objective of this study was to determine the expiration date of the device. The BioGenex ER88 Antibody was stored at 2-8°C continuous. Three lots of the device were tested after 24 months of storage following the standard in-house quality control testing procedures. Results of this study indicated that this device was stable for at least 24 months at 2-8°C.

Shipping stress studies were carried out on three lots of the device by continuous exposure to extreme temperature condition 45℃ for 48 hours. Results of this study indicated that this device was stable after continuous 48 hour exposure at 45°C.

CONCLUSION:

The results indicate that BioGenex Monoclonal Anti-Estrogen Receptor (Clone ER88) is substantially equivalent to dextran-coated charcoal (DCC) technique and Dako estrogen receptor antibody (K993957).

BIBLIOGRAPHY:

Ferrero-Poüs M, Trassard, M, Le Doussal V, Hacène K, Tubiana-Hulin M, Spyratos, F. Comparison of enzyme immunoassay and immunohistochemical measurements of estrogen and progesterone receptors in breast cancer patients. Appl Immunohistochem & Mol Mor 2001:9:267-275.

Fitzgibbons PL, Page DL, Weaver D, Thor AD, Allred DC, Clark GM, Ruby SG, O'Malley F, Simpson JF, Connolly JL, Hayes DF, Edge SB, Lichter A, Schnitt SJ, Prognostic factors in breast cancer. College of American Pathologists Consensus Statement 1999. Arch Pathol Lab Med. 2000 Jul:124(7):966-78.

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Kell D, Kamel O, Rouse R, Immunohistochemical analysis of breast carcinoma estrogen reen D, realler o, receptors in paraffin embedded tissue. Appl Immunohistochem 1993;1(4):275-281.

Goussard J. Paraffin section immunocytochemistry and cytosol-based ligand-binding assays for ER and PR detection in breast cancer: the time has come for more objectivity. Cancer Lett 1998 Oct 23;132(1-2):61-66.

NIH Consensus Statement. Adjuvant Therapy for Breast Cancer, Volume 17, Number 4, November 1–3, 2000 National Institutes of Health, Office of the Director, pg. 8.

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DEPARTMENT OF HEALTH & HUMAN SERVICES

Image /page/6/Picture/1 description: The image is a black and white logo for the U.S. Department of Health & Human Services. The logo features a stylized caduceus symbol, which is a staff with two snakes coiled around it. The words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" are arranged in a circular pattern around the caduceus symbol.

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

FEB 2 8 2002

Gurvinder S. Nanda, Ph.D. Manager, Regulatory Affairs BioGenex Laboratories, Inc. 4600 Norris Canyon Road San Ramon, CA 94583

Re: K013148

Trade/Device Name: BioGenex Mouse Anti-Estrogen Receptor Antibody (Clone ER88) Regulation Number: 21 CFR 864.1860 Regulation Name: Immunohistological Reagents and Kits Regulatory Class: Class II Product Code: MXZ Dated: December 20, 2001 Received: December 21, 2001

Dear Dr. Nanda:

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.

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 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 801); 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.

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Page 2 -

This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed nothleation. The I Driving of succion for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (2) CFR Part 801 and 1 IT you desire spoonne active in yagostic devices), please contact the Office of Compliance at additionally 607.10 for in an ally, for questions on the promotion and advertising of your device, (301) 594-4566. Fraundomary, For quice at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small mioritiation on your responsive as assistance at its toll-free number (800) 638-2041 or Manufacturers International and Oblass "http://www.fda.gov/cdrh/dsma/dsmamain.html".

Sincerely yours,

Steven Sutman

Steven I. Gutman, M.D., M.B.A. Director Division of Clinical Laboratory Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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INDICATIONS FOR USE STATEMENT

510(k) Number (if known): K013148

BioGenex Mouse Anti-Estrogen Receptor Antibody Device Name: (Clone ER88)

The BioGenex Mouse Monoclonal Anti-Estrogen Receptor Indications for Use: Antibody (Clone ER88) is an immunohistochemical (IHC) assay and is intended for laboratory use to qualitatively identify by light microscopy human estrogen receptor in normal and/or pathological paraffin-embedded, formalinfixed tissues. The ER88 antibody specifically binds to antigens located in the nucleus of cell populations that express estrogen receptor in normal and abnormal tissues. This antibody is indicated as an aid in assessing patient response to hormonal therapy and as an aid in the prognosis and management of breast cancer patients. The clinical interpretation of any staining or its absence should be complemented by morphological studies using proper controls and should be evaluated within the context of the patient's clinical history and other diagnostic tests by a qualified pathologist.
optimally been have antibodies ER88 BioGenex manufactured for use with BioGenex Super Sensitive MultiLink Detection Systems with or without BioGenex Automated Staining Systems.

(Please do not write below this line-continue on another page if needed)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Prescription Use
(Per 21 CFR 801.109) OR Over – The – Counter Use
(Optional format 1-2-96)

Sousan S.Altaie

(Division Sign-Off)
Division of Clinical Laboratory Devices

510(k) Number K013148

Regulation Number and Section

§ 864.1860 Immunohistochemistry reagents and kits.

(a)
Identification. Immunohistochemistry test systems (IHC's) are in vitro diagnostic devices consisting of polyclonal or monoclonal antibodies labeled with directions for use and performance claims, which may be packaged with ancillary reagents in kits. Their intended use is to identify, by immunological techniques, antigens in tissues or cytologic specimens. Similar devices intended for use with flow cytometry devices are not considered IHC's.(b)
Classification of immunohistochemistry devices. (1) Class I (general controls). Except as described in paragraphs (b)(2) and (b)(3) of this section, these devices are exempt from the premarket notification requirements in part 807, subpart E of this chapter. This exemption applies to IHC's that provide the pathologist with adjunctive diagnostic information that may be incorporated into the pathologist's report, but that is not ordinarily reported to the clinician as an independent finding. These IHC's are used after the primary diagnosis of tumor (neoplasm) has been made by conventional histopathology using nonimmunologic histochemical stains, such as hematoxylin and eosin. Examples of class I IHC's are differentiation markers that are used as adjunctive tests to subclassify tumors, such as keratin.(2) Class II (special control, guidance document: “FDA Guidance for Submission of Immunohistochemistry Applications to the FDA,” Center for Devices and Radiologic Health, 1998). These IHC's are intended for the detection and/or measurement of certain target analytes in order to provide prognostic or predictive data that are not directly confirmed by routine histopathologic internal and external control specimens. These IHC's provide the pathologist with information that is ordinarily reported as independent diagnostic information to the ordering clinician, and the claims associated with these data are widely accepted and supported by valid scientific evidence. Examples of class II IHC's are those intended for semiquantitative measurement of an analyte, such as hormone receptors in breast cancer.
(3) Class III (premarket approval). IHC's intended for any use not described in paragraphs (b)(1) or (b)(2) of this section.
(c)
Date of PMA or notice of completion of a PDP is required. As of May 28, 1976, an approval under section 515 of the Federal Food, Drug, and Cosmetic Act is required for any device described in paragraph (b)(3) of this section before this device may be commercially distributed. See § 864.3.