The Access Thyroglobulin Antibody II assay is a paramagnetic particle, chemiluminescent immunoassay for the quantitative determination of thyroglobulin antibody levels in human serum and plasma using the Access Immunoassay Systems. The measurement of thyroid autoantibodies may aid in the diagnosis of Hashimoto's disease, nontoxic goter, and Graves' disease.

Device Description

The Access Thyroqlobulin Antibody II assay is a paramagnetic particle, chemiluminescent immunoassay for the quantitative determination of thyroglobulin antibody levels in human serum and plasma using the Access Immunoassay Systems. The measurement of thyroid autoantibodies may aid in the diagnosis of Hashimoto's disease, nontoxic goiter, and Graves' disease.

The Access Thyroglobulin Antibody II assay consists of the reagent pack and calibrators. Other items needed to run the assay include substrate and wash buffers. The assay is run on Access 2 Immunoassay Analyzers.

The device modifications described in this submission impact the Access Thyroqlobulin Antibody II reagent pack only; they do not impact or change the other components that are used with this reagent pack. The modification does not affect the intended use or indications of the device or alter the fundamental scientific technology of the device.

A description of the reagent pack is provided below.

Well	Ingredients
R1a:	Dynabeads* paramagnetic particles coated with streptavidin andcoupled to biotinylated human thyroglobulin, suspended in a TRISbuffer with protein (bovine), < 0.1% sodium azide, and 0.1%ProClin** 300.
R1b:	Human thyroglobulin-alkaline phosphatase (bovine) conjugate in aTRIS buffer with protein (bovine), < 0.1% sodium azide, and 0.1%ProClin 300.
R1c:	TRIS buffer with protein (bovine), < 0.1% sodium azide and 0.1%ProClin 300.
R1d:	TRIS buffer with blocking polymer, < 0.1% sodium azide and 0.1%ProClin 300.

AI/ML Overview

Here's an analysis of the provided text, outlining the acceptance criteria and study details for the "Access Thyroglobulin Antibody II" device:

Device: Access Thyroglobulin Antibody II

The study in the document focuses on the modified Access Thyroglobulin Antibody II assay and compares it to the previously cleared predicate device (Access Thyroglobulin Antibody II Assay, FDA 510(k) Number K112933). The goal is to demonstrate substantial equivalence of the modified device.

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly present acceptance criteria in a dedicated table format. Instead, it describes performance characteristics and the results obtained. I've reconstructed a table based on the implicit criteria derived from the reported performance, especially where a target value or range is given (e.g., for imprecision, biases, or correlation).

Performance Characteristic	Acceptance Criteria (Implicit/Explicit)	Reported Device Performance (Modified Device)
Measuring Range	(Compared to predicate's 0.9-2,500 IU/mL)	1.5-2,500 IU/mL
Imprecision	Predicate: SD < 1.5 for values < 15 IU/mL; CV < 10% for values ≥ 15 IU/mL	Within Laboratory (Total): - SD ≤ 1.5 at concentrations < 15 IU/mL - CV ≤ 10.0 % at concentrations ≥ 15 IU/mL and < 1000 IU/mL - CV ≤ 15.0% for concentrations ≥ 1000 IU/mL
Reproducibility	(Not explicitly defined for predicate, but performance is reported)	Reproducibility: - SD ≤ 2.3 at concentrations < 15 IU/mL - CV ≤ 15.0 % at concentrations ≥ 15 IU/mL and < 1000 IU/mL - CV ≤ 20.0% for concentrations ≥ 1000 IU/mL
High-dose Hook Effect	No significant hook effect expected.	No high-dose hook effect at concentrations up to at least 50,000 IU/mL.
Linearity	(Expected to be linear across the measuring range)	Demonstrated to be linear across the range of the assay (1.5 to 2,500 IU/mL) in both serum and plasma samples.
Limit of Blank (LoB)	(Lower than LoD/LoQ)	0.0 IU/mL
Limit of Detection (LoD)	(Lower than LoQ)	0.4 IU/mL
Limit of Quantitation (LoQ)	≤ 20% within-lab CV at LoQ.	1.5 IU/mL (with ≤ 20% within-lab CV)
Analytical Specificity	100% agreement with predicate for cross-reactive disease states; No significant interference (≤ ±1.5 IU/mL for <15 IU/mL, ≤ ±10% for ≥15 IU/mL)	- Cross-reactive disease states: 100% total agreement with the predicate assay. - Potential interferents (including 3510 ng/mL biotin): No significant interference (defined as change in concentration within ± 1.5 IU/mL for samples < 15 IU/mL and within ± 10% for samples ≥ 15 IU/mL) observed at clinically relevant concentrations (approx. 4 IU/mL and 100 IU/mL).
Matrix Comparison	Slope of 1.00 ± 0.12 and R² ≥ 0.92 for correlation between serum, lithium heparin, and EDTA plasma samples.	Results met the acceptance criteria of slope of 1.00 ± 0.12 and R² ≥ 0.92.
Method Comparison	(Comparison to a commercially available immunoassay, showing good correlation and agreement, implicitly) Reported statistics: Slope 1.03 (1.00-1.06), Y-Intercept -0.13 (-0.68-0.30), R 0.99 (Passing-Bablok)	Slope: 1.03 (95% CI: 1.00-1.06) Y-Intercept: -0.13 (95% CI: -0.68-0.30) Correlation Coefficient R: 0.99 (Passing-Bablok regression)

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

Method Comparison: n = 123 samples. Data provenance not specified (country of origin, retrospective/prospective).
Imprecision: Not specified, but involved reagent lots and instrument details suggest laboratory testing.
Reproducibility: Not specified, but involved reagent lots and instrument details suggest laboratory testing.
High-dose Hook Effect: Not specified how many samples were tested, but concentrations up to 50,000 IU/mL were used.
Linearity: Not specified how many samples were tested, but both serum and plasma samples were used.
Sensitivity (LoB, LoD, LoQ): Not specified how many samples were used, but involved 2 reagent lots and 2 instruments over a minimum of 3 days (LoB) or 5 days (LoD, LoQ).
Analytical Specificity:
- Cross-reactive disease states: "Samples with potential cross-reactive disease states were tested." Number of samples not specified.
- Potential interferents: "Patient serum samples containing two levels of thyroglobulin antibody at clinically relevant concentrations of approximately 4 IU/mL and 100 IU/mL." Number of samples not specified, but specific interferents (like biotin at 3510 ng/mL) were tested.
Matrix Comparison: Fifty (50) matched sets of serum, lithium heparin plasma, and EDTA plasma samples.

Data Provenance: The document does not specify the country of origin for any of the samples used in these studies, nor does it explicitly state if the studies were retrospective or prospective, though "patient samples" implies retrospective collection or prospective enrollment for the study.

3. Number of Experts Used to Establish Ground Truth and Qualifications

This device is an in vitro diagnostic (IVD) immunoassay, not an imaging device typically requiring expert interpretation for ground truth. Therefore, the concept of "experts" establishing ground truth in the traditional sense of clinical diagnosis (e.g., radiologists, pathologists) does not directly apply here.

For IVDs, "ground truth" is typically established by:

Reference methods/devices.
Certified reference materials.
Pathology or histopathology (for certain tests).
Clinical outcomes/diagnosis (for certain tests).
Known concentrations in spiked samples or characterized panels.

In this document:

The "Method Comparison" used a "commercially available immunoassay" as a comparator, which serves as a de facto reference for comparison.
Analytical specificity testing used "potential cross-reactive disease states" and "potential interferents" for which the expected results (presence/absence of Thyroglobulin Antibody, or known interference levels) would be pre-established or determined by a reference method.
Sensitivity studies (LoB, LoD, LoQ) involve statistical calculations based on repeated measurements of samples with very low or zero analyte concentrations, not expert consensus.
Concentration ranges for linearity were established using characterized samples.

Therefore, no information on human experts establishing ground truth is provided, as it's not relevant for this type of device validation.

4. Adjudication Method for the Test Set

Adjudication methods (like 2+1, 3+1) are typically used for studies where multiple human readers interpret medical images or complex data, and their interpretations need to be reconciled to establish a ground truth.

Since this is an in vitro diagnostic device measuring an analyte concentration, and the gold standard for comparison typically involves laboratory methods or reference materials, an adjudication method for a test set is not applicable or described in this document. The "ground truth" for the various performance characteristics is established by analytical methods and comparisons to reference standards or predicate devices.

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

No, a multi-reader multi-case (MRMC) comparative effectiveness study was not performed. This type of study is relevant for medical imaging devices where the performance of human readers, with and without AI assistance, is evaluated using a set of cases. This document describes an in vitro diagnostic device, an immunoassay, which does not involve human interpretation of images or complex data in a way that MRMC studies would be applicable.

6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study

Yes, the studies described are all standalone performance evaluations of the Access Thyroglobulin Antibody II assay. This means the studies assess the device's ability to measure thyroglobulin antibody levels independent of human intervention in the interpretation of the result in the context of the device's analytical performance. The Access Immunoassay Systems are automated, and the assay's performance metrics (imprecision, linearity, sensitivity, specificity, etc.) are solely based on the analytical capabilities of the device itself.

7. The Type of Ground Truth Used

The type of "ground truth" used varies depending on the specific study:

Method Comparison: A "commercially available immunoassay" served as the comparative standard. The results from this predicate/reference immunoassay formed the basis for comparing the new device's measurements.
Imprecision & Reproducibility: Ground truth is implicit in the known characteristics of the control materials or spiked samples used, and the statistical variability observed from repeated measurements defines the performance.
High-dose Hook Effect & Linearity: Ground truth is established by using samples with known or precisely characterized concentrations, often prepared by dilution or spiking.
Sensitivity (LoB, LoD, LoQ): Statistical models are used based on repeated measurements of blank samples and samples with very low (but known) analyte concentrations.
Analytical Specificity:
- Cross-reactive disease states: Likely involved samples from patients with these conditions, where the presence/absence of TgAb would have been characterized by a reference method or clinical diagnosis. The "ground truth" then is the expected TgAb status based on the sample's origin.
- Potential interferents: Involved adding known concentrations of interfering substances to samples with known TgAb concentrations. The "ground truth" is the expected TgAb concentration without interference.
Matrix Comparison: Used matched samples from different matrices (serum, plasma), where the inherent TgAb concentration within a given patient sample is the ground truth against which each matrix measurement is compared.

In summary, the ground truth for this IVD device is primarily established through comparisons to established reference methods/predicate devices, known concentrations in characterized samples (spiked or diluted), and statistical analysis of performance with control materials.

8. The Sample Size for the Training Set

The document describes studies for validation of a modified device, demonstrating substantial equivalence to a predicate. It does not mention a "training set" in the context of developing an algorithm or AI model. This is an immunoassay, not a machine learning model that typically requires a large training dataset. The studies focus on analytical performance rather than diagnostic accuracy determined by a machine learning pipeline.

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

As noted above, there is no mention of a "training set" or "ground truth" established for training in this document, as the device is an immunoassay not based on a trainable algorithm.

Summary

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September 26, 2023

Beckman Coulter, Inc. Adam Viitala Senior Manager, Regulatory Affairs 1000 Lake Hazeltine Drive Chaska, Minnesota 55318

Re: K213517

Trade/Device Name: Access Thyroglobulin Antibody II Regulation Number: 21 CFR 866.5870 Regulation Name: Thyroid Autoantibody Immunological Test System Regulatory Class: Class II Product Code: JZO Dated: March 10, 2023 Received: March 10, 2023

Dear Adam Viitala:

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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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

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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 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; 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 https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.

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/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). 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 (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely,

Ying Mao -S

Ying Mao, Ph.D. Branch Chief Division of Immunology and Hematology Devices OHT7: Office of In Vitro Diagnostics Office of Product Evaluation and Quality Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K213517

Device Name Access Thyroglobulin Antibody II

Indications for Use (Describe)

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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Access Thyroglobulin Antibody II 510(K) Summary

Immunodiagnostic Development Center

1000 Lake Hazeltine Drive Chaska, Minnesota 55318-1084

510(k) Summary

This summary of 510(k) safety and effectiveness information is being submitted in accordance with the requirements of 21 CFR 807.92(a)(1).

The assigned 510(k) number is K213517.

Submitted By:

Beckman Coulter, Inc. 1000 Lake Hazeltine Drive Chaska, MN 55318 Telephone: (952) 448-4848

Contact Person:

Adam Viitala 1000 Lake Hazeltine Drive Chaska, MN 55318 Phone: +1 (520) 496-4517

Alternate Contact:

Muhammad Sheikh Office Phone: (952) 368-1142

Date Prepared:

September 22, 2023

Device Name:

Proprietary / Trade Name: Access Thyroglobulin Antibody II Common Name: Thyroid autoantibody immunological test system Classification Description: Thyroid autoantibody immunological test system. Classification Regulation: 21 CFR 866.5870 Classification Product Code: JZO

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Predicate Device:

The modified Access Thyroglobulin Antibody II Assay claims substantial equivalence to previously cleared Access Thyroglobulin Antibody II Assay. FDA 510(k) Number K112933, cleared December 27, 2011.

Device Description:

A description of the reagent pack is provided below.

Well	Ingredients
R1a:	Dynabeads* paramagnetic particles coated with streptavidin andcoupled to biotinylated human thyroglobulin, suspended in a TRISbuffer with protein (bovine), < 0.1% sodium azide, and 0.1%ProClin** 300.
R1b:	Human thyroglobulin-alkaline phosphatase (bovine) conjugate in aTRIS buffer with protein (bovine), < 0.1% sodium azide, and 0.1%ProClin 300.
R1c:	TRIS buffer with protein (bovine), < 0.1% sodium azide and 0.1%ProClin 300.
R1d:	TRIS buffer with blocking polymer, < 0.1% sodium azide and 0.1%ProClin 300.

*Dynabead® is a registered trademark of Dynal A.S.. Oslo. Norway

**ProClin™ is a trademark of The Dow Chemical Company ("Dow") or an affiliate company of Dow.

Intended Use:

The Access Thyroqlobulin Antibody II assay is a paramagnetic particle, chemiluminescent immunoassay for the quantitative determination of thyroolobulin antibody levels in human serum and plasma using the Access Immunoassay Systems. The measurement of thyroid autoantibodies may aid in the diagnosis of Hashimoto's disease, nontoxic goiter, and Graves' disease.

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Comparison to the Predicate:

The modified device and previously cleared predicate device are compared below.

Characteristic	Predicate DeviceAccess Thyroglobulin Antibody II(K112933)	Modified DeviceAccess Thyroglobulin Antibody II
Intended Use	The Access ThyroglobulinAntibody II assay is aparamagnetic particle,chemiluminescent immunoassayfor the quantitative determinationof thyroglobulin antibody levels inhuman serum and plasma usingthe Access ImmunoassaySystems. The measurement ofthyroid autoantibodies may aid inthe diagnosis of Hashimoto'sdisease, nontoxic goiter, andGraves' disease.	Same
Analyte Measured	Thyroglobulin Antibody	Same
Technology	Sandwich immunoassay	Same
Format	Chemiluminescent	Same
Method	Automated	Same
Sample Type	Human serum or plasma	Same
Assay Throughput	Approximately 48 Minutes	Same
Sample Volume	10 µL	Same
Measuring Range	0.9-2,500 IU/mL	1.5-2,500 IU/mL
Blocker reagents	Free biotin and alkalinephosphatase not included inreagent pack	Biotin and alkaline phosphataseincluded in reagent pack asblockers
Biotin Interference	Specimens with biotinconcentrations ≤ 100 ng/mLdemonstrated non-significant bias(≤ 10%) in results. Biotinconcentrations > 100 ng/mL canlead to significant (> 10%)negative bias in Thyroglobulin AbII results.	No significant interference (±10%) observed in samplescontaining up to 3,510 ng/mL ofbiotin.
Imprecision	SD < 1.5 for values < 15 IU/mLCV < 10% for values ≥ 15 IU/mL	SD ≤ 1.5 for values < 15 IU/mLCV ≤ 10.0% for values ≥ 15IU/mL and < 1000 IU/mLCV ≤ 15.0% for values ≥ 1000IU/mL

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Summarv of Studies:

Method Comparison: A comparison of values using the Access Thyroglobulin Antibody II assay on the Access Immunoassay system and a commercially available immunoassay gave the statistical data provided in the following table. The data was analyzed by Passing-Bablok regression and Pearon's correlation and followed the CLSI EP09c quideline.

n	ConcentrationRange(IU/mL)	Slope(95% CI)	Y-Intercept(95% CI)	CorrelationCoefficientR
123	1.79-2216.25	1.03 (1.00-1.06)	-0.13 (-0.68-0.30)	0.99

Imprecision: The Access Thyroglobulin Antibody II assay exhibits within laboratory (total) imprecision of standard deviation (SD) ≤ 1.5 at concentrations <15 IU/mL, CV ≤10.0 % at concentrations ≥ 15 IU/mL and < 1000 IU/mL, and CV ≤ 15.0% for concentrations ≥ 1000 IU/mL.

Reproducibility: The Access Thyroglobulin Antibody II assay exhibits reproducibility of standard deviation (SD) ≤ 2.3 at concentrations <15 IU/mL, CV ≤15.0 % at concentrations ≥ 15 IU/mL and < 1000 IU/mL, and CV ≤ 20.0% for concentrations ≥ 1000 IU/mL.

High-dose Hook Effect: The Access Thyroglobulin Antibody II assay demonstrated no high-dose hook effect at concentrations up to at least 50,000 IU/mL.

Linearity: The Access Thyroglobulin Antibody II assay has been demonstrated to be linear across the range of the assay (1.5 to 2,500 IU/mL) in both serum and plasma samples.

Sensitivity: Limit of Blank (LoB), Limit of Detection (LoD), and Limit of Quantitation (LoQ) studies were conducted on multiple Access Immunoassay Systems following CLSI guideline EP17-A2. The LoB study included 2 reagent lots and 2 instruments over a minimum of 3 days. The LoD and LoQ studies included 2 reagent lots and 2 instruments over a minimum of 5 days.

	IU/mL
Limit of Blank (LoB)	0.0
Limit of Detection (LoD)	0.4
Limit of Quantitation (LoQ)	1.5
≤ 20% within-lab CV

Analytical Specificity: Samples with potential cross-reactive disease states were tested on both the modified Access Thyroglobulin Antibody II assay and the predicate

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currently marketed Access Thyroglobulin Antibody II assay, and showed 100% total agreement.

Potential interferents were tested at one concentration and compared to control samples without potential interferents. Testing was completed on patient serum samples containing two levels of thyroglobulin antibody at clinically relevant concentrations of approximately 4 IU/mL and 100 IU/mL. Testing of all potential interferents, including biotin at a concentration of 3510 ng/mL, with Access TgAb found that there is no significant interference, as defined by a change in concentration between the control and the test samples within ± 1.5 IU/mL for samples below 15 IU/mL and within ± 10% for samples greater than or equal to 15 IU/mL.

Matrix Comparison: A comparison of fifty (50) matched sets of serum, lithium heparin plasma and EDTA plasma samples with thyroglobulin antibody concentrations with a range of approximately 0 IU/mL to 2,500 IU/mL were compared using Passing-Bablok linear regression analysis. The results met the acceptance criteria of slope of 1.00 ± 0.12 and R2 ≥ 0.92.

Conclusion:

The modified device has the same intended use and fundamental scientific technology as the predicate device. The modified device is as safe and effective as the predicate device, as demonstrated through verification testing.

The information provided in this submission demonstrates that the modified device is substantially equivalent to the predicate device.

Regulation Number and Section

§ 866.5870 Thyroid autoantibody immunological test system.

(a)
Identification. A thyroid autoantibody immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the thyroid autoantibodies (antibodies produced against the body's own tissues). Measurement of thyroid autoantibodies may aid in the diagnosis of certain thyroid disorders, such as Hashimoto's disease (chronic lymphocytic thyroiditis), nontoxic goiter (enlargement of thyroid gland), Grave's disease (enlargement of the thyroid gland with protrusion of the eyeballs), and cancer of the thyroid.(b)
Classification. Class II (performance standards).