K Number

Device Name

THYROID STIMULATING IMMUNOGLOBULIN REPORTER ASSAY

Manufacturer

DIAGNOSTIC HYBRIDS, INC.

Date Cleared

2009-05-21

(185 days)

Product Code

JZO

Regulation Number

866.5870

Intended Use

The Thyretain ™ TSI Reporter BioAssay is intended for the qualitative detection in serum of thyroid stimulating autoantibodies to the thyroid stimulating hormone (TSH) receptors (TSHRs) on the thyroid. The detection of these stimulating autoantibodies, in conjunction with other clinical and laboratory findings, may be useful as an aid in the differential diagnosis of patients with Graves' disease (GD).

Device Description

The Thyretain ™ TSI Reporter BioAssay (TSI Reporter) utilizes a patented bioassay technology to detect thyroid stimulating immunoglobulin (TSI) in human serum. Genetically engineered Chinese hamster ovary (CHO) cells, expressing a chimeric form' of the human thyroid stimulating hormone receptor (TSHR) and a cyclic adenosine monophosphate (cAMP) induced luciferase reporter gene, are cryogenically preserved and provided in measured aliquots. The CHO Mc4 cell line has a nucleic acid sequence encoding a chimeric human TSH receptor, designed for reduced response to thyroid blocking immunoglobulin (TBI) activity. Thus, the hTSH receptor, comprised of 730 amino acids, has amino acid residues 262 to 335 replaced by the equivalently located 73 amino acid residues of the rat Luteinizing Hormone receptor to form the chimeric TSHR. This chimeric receptor is linked to a firefly luciferase reporter gene in operable combination with a glycoprotein hormone a-subunit promoter. The cells are seeded and grown for 15 to 18 hours to confluent monolayers in a 96-well plate. Patient sera, reference control, positive and normal controls and are diluted with a proprietary reaction buffer (RB), added to the cell monolayers and allowed to react with the cells for 3 hours. During this induction period TSI, if present in the patient serum, bind to the chimeric human TSHR on the cell surface. This binding event induces a signaling cascade resulting in increased production of intra-cellular cAMP. This increased production of cAMP is evidenced by increased production of luciferase. At the conclusion of the 3 hour induction period the cells are lysed. Luciferase levels are then measured using a luminometer. A significant increase in luminescence over the Reference Control indicates the presence of TSI antibodies in the sample.

More Information

Contact

Type

Center

Panel

Date Received

Product Code

Subsequent Product Codes

Applicant Name (Manufacturer)

Device Name

Decision

Street 1

Street 2

City

State

Country Code

ZIP

Postal Code

Class Advise Committee

SSP Indicator

Third Party Reviewed

Expedited Review

Predicate Devices

KRONUS TSH Receptor Antibody (TRAb) Coated Tube (CT) Assay Kit k()32134

Reference Devices

Not Found

AI/ML (Artificial Intelligence / Machine Learning)

No
The device description details a bioassay based on cell culture and luminescence measurement. While statistical analysis (ROC curve) is mentioned for cutoff determination, there is no indication of AI or ML being used in the assay itself or the interpretation of results beyond a simple cutoff.

Therapeutic

No
The device is an in vitro diagnostic assay intended for the qualitative detection of autoantibodies to aid in the differential diagnosis of Graves' disease, not for direct therapy.

Diagnostic

Yes

The 'Intended Use / Indications for Use' section states that the device "may be useful as an aid in the differential diagnosis of patients with Graves' disease (GD)." This explicitly indicates its role in diagnosis.

SaMD (Software as a Medical Device)

The device description clearly outlines a bioassay kit that includes genetically engineered cells, reaction buffer, and requires a luminometer for measurement. This involves significant hardware and biological components, not just software.

IVD (In Vitro Diagnostic)

Yes, this device is an IVD (In Vitro Diagnostic).

Here's why:

Intended Use: The "Intended Use / Indications for Use" section explicitly states that the device is "intended for the qualitative detection in serum of thyroid stimulating autoantibodies...". This indicates that the device is used to examine specimens derived from the human body (serum) to provide information for diagnostic purposes.
Device Description: The description details a laboratory assay that uses biological reagents (CHO cells, patient sera, controls) and measures a biological marker (luciferase levels as an indicator of TSI antibodies) in a sample. This is characteristic of an in vitro diagnostic test.
Clinical Context: The intended use also states that the detection of these antibodies "in conjunction with other clinical and laboratory findings, may be useful as an aid in the differential diagnosis of patients with Graves' disease (GD)." This clearly places the device within a clinical diagnostic context.
Performance Studies: The document describes performance studies, including clinical performance studies comparing the device to a predicate device, which are standard requirements for IVD devices seeking regulatory approval.

Therefore, based on the provided information, the Thyretain ™ TSI Reporter BioAssay fits the definition of an In Vitro Diagnostic device.

PCCP (Predetermined Change Control Plan) Authorized

N/A

Overview

Intended Use / Indications for Use

Product codes (comma separated list FDA assigned to the subject device)

JZO

Device Description

The cells are seeded and grown for 15 to 18 hours to confluent monolayers in a 96-well plate. Patient sera, reference control, positive and normal controls and are diluted with a proprietary reaction buffer (RB), added to the cell monolayers and allowed to react with the cells for 3 hours. During this induction period TSI, if present in the patient serum, bind to the chimeric human TSHR on the cell surface. This binding event induces a signaling cascade resulting in increased production of intra-cellular cAMP. This increased production of cAMP is evidenced by increased production of luciferase. At the conclusion of the 3 hour induction period the cells are lysed. Luciferase levels are then measured using a luminometer. A significant increase in luminescence over the Reference Control indicates the presence of TSI antibodies in the sample.

Mentions image processing

Not Found

Mentions AI, DNN, or ML

Not Found

Input Imaging Modality

Not Found

Anatomical Site

Thyroid (on the thyroid)

Indicated Patient Age Range

Not Found

Intended User / Care Setting

Not Found

Description of the training set, sample size, data source, and annotation protocol

A "training-set" of samples was used to establish a preliminary cut-off. The TSI Reporter prototype device was tested for assay cutoff limits through testing of 30 subjects with diagnosed Graves' disease and 44 normal subjects with no known or clinically diagnosed thyroid disease. The SRR% data obtained for each of these subjects were analyzed using receiver operating characteristic (ROC) curve analysis.

Description of the test set, sample size, data source, and annotation protocol

A "testing-set" of samples was used to verify the preliminary cutoff, with an additional 50 GD positive sera obtained from physicians with diagnostic information and 140 normal sera.

Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)

Non-Clinical Performance:

Limit of Detection: The LoD for the TSI Reporter was determined to be 89.14 %SRR based on CLSI EP17A calculations.
Interference by Endogenous Substances: No interference observed with bilirubin up to 36.6 mg/dL, hemoglobin up to 250 mg/dL, and lipids up to 1,168 mg/dL.
Cross-reactivity by Glycoprotein Hormones: Tested with luteinizing hormone up to 625 mIU/mL, human chorionic gonadatrophin up to 40,625 mIU/mL, follicle stimulating hormone up to 2,000 mIU/mL, and thyroid stimulating hormone up to 0.35 mIU/mL.
Cross-reactivity with Other Autoantibodies: Tested 36 samples with autoimmune diseases (16 Hashimoto's, 10 Rheumatoid Arthritis, 10 Systemic Lupus Erythematosus). One Hashimoto's sample tested positive (with TSH levels near interference level), others negative.
Assay Cutoff: Preliminary cut-off of ≥ 140% over Reference Control established using training set and confirmed in clinical studies. Verification testing with a manufactured sample near the cutoff (~157%) yielded positive results ≥75% of the time and negative results ≤25% of the time over 20 days (n=120).
Intra-Assay Precision: Average intra-plate (n=16) variation (CV %) was 4.7%.
Inter-Assay Precision (Intra-Day): Average inter-assay CV% for high, medium, and low TSI containing serum were 3.6%, 2.6%, and 4.2% respectively on day one. Reference Control, TSI Positive Control, and Normal Control were 2.4%, 5.0%, and 5.0% respectively. Overall inter-assay variation within this day was 3.8%.
Inter-Assay Precision (Inter-Day): Overall average inter-assay variation across 20 days was 12%. Variation for high, medium, low TSI serum, normal serum, TSI Positive Control, and Reference Control (n=120, n=120, n=120, n=40 and n=80) was 12%, 13%, 16%, 12%, 12% and 7% respectively.
Assay Reproducibility:
- Study 1: Tested 4 panel samples (A, B, C, D) at trained sites (Site 1-COH, Site 2-MN, Site 3-NC Technician 1, Site 3-NC Technician 2) twice a day over 8 days. Sample A and B: 180/180 Positive Ratio. Sample C: 180/180 Negative Ratio. Sample D: 139/180 Positive Ratio. Overall CV% for A, B, C, D were 23.7%, 23.7%, 24.6%, and 17.9% respectively.
- Study 2: Tested 3 samples (E, F, G) near cutoff at two sites twice a day for 5 days. Sample E: 60/60 Positive Ratio. Sample F and G: 60/60 Negative Ratio. Overall CV% for E, F, G were 15.0%, 20.3%, and 20.5% respectively.
Assay Stability: Materials, reagents, and components are stable for a minimum of 12 months.

Clinical Performance:

Study 1 (Sites 1-COH and 2-MN combined):
- Sample Size: 299 specimens (out of 312, 1 excluded for insufficient quantity, 12 excluded for indeterminate comparator results).
- Study Type: Comparison study against KRONUS TRAb (Comparator Device).
- Key Results: Positive Percent Agreement: 93.8% (95% CI: 88.2% to 96.8%). Negative Percent Agreement: 89.5% (95% CI: 84.0% to 93.2%).
Study 2 (Site 3-NC):
- Sample Size: 231 specimens (out of 247, 16 excluded for indeterminate comparator results).
- Study Type: Comparison study against KRONUS TRAb (Comparator Device).
- Key Results: Positive Percent Agreement: 74.6% (95% CI: 63.5% to 83.3%). Negative Percent Agreement: 97.5% (95% CI: 93.8% to 99.0%).
- Note: The decreased PPA was attributed to specificity differences as the comparator device detects both stimulating (TSI) and blocking (TBI) antibodies, while the subject device detects only TSI. Exclusion of 6 patients meeting ATA definition of hypothyroidism from the dataset increased PPA to 81.5% (95% CI: 70.4% to 89.1%).

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

Clinical Sensitivity and Specificity: (Based on 249 characterized specimens with Graves Disease and other autoimmune diseases/healthy controls)

Clinical Sensitivity: 92.0% (46/50)
Clinical Specificity: 99.5% (198/199)

Clinical Performance (Sites 1-COH and 2-MN combined):

Positive Percent Agreement: 93.8%
Negative Percent Agreement: 89.5%

Clinical Performance (Site 3-NC):

Positive Percent Agreement: 74.6%
Negative Percent Agreement: 97.5%

Predicate Device(s): If the device was cleared using the 510(k) pathway, identify the Predicate Device(s) K/DEN number used to claim substantial equivalence and list them here in a comma separated list exactly as they appear in the text. List the primary predicate first in the list.

KRONUS TSH Receptor Antibody (TRAb) Coated Tube (CT) Assay Kit k()32134

Reference Device(s): Identify the Reference Device(s) K/DEN number and list them here in a comma separated list exactly as they appear in the text.

Not Found

Predetermined Change Control Plan (PCCP) - All Relevant Information for the subject device only (e.g. presence / absence, what scope was granted / cleared under the PCCP, any restrictions, etc).

Not Found

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).

Summary

KC83391

Thyretain™ TSI Reporter BioAssay SECTION 05, 510(K) SUMMARY

Image /page/0/Picture/2 description: The image shows the logo for Diagnostic Hybrids. The logo features the company name in bold, sans-serif font, with the word "DIAGNOSTIC" stacked above "HYBRIDS." Below the company name, the tagline "Integrating Science and Humanity" is displayed in a smaller, italicized font. To the right of the text, there is a stylized graphic of a human figure intertwined with a DNA double helix.

APPLICANT

DIAGNOSTIC HYBRIDS, INC. 1055 East State Street Suite 100 Athens, OHIO 45701

MAY 21 2009

CONTACT INFORMATION

Ronald H. Lollar Senior Director, Product Realization, Management, and Marketing E-mail: lollar@dhiusa.com Telephone: 740-589-3300 Desk Extension: 740-589-3373 FAX: 740-593-8437

DATE OF PREPARATION OF 510(k) SUMMARY

November 14, 2008

DEVICE NAME

Trade name: Thyretain TM TSI Reporter BioAssay Common name: TSI Reporter Classification name: System, Test, Thyroid Autoantibody Product Code: JZO Regulation: 21 CFR § 866.5870, Thyroid Autoantibody Immunological Test

DEVICE DESCRIPTION

Thyretain TM TSI Reporter BioAssay 5/07/2009 Section 05, Page 2 of 10

KIT COMPONENTS

1. CHO Mc4 FreshFrozenCells®: Cryovials containing CHO Mc4 cells cryogenically preserved in cryoprotective medium containing DMSO. Reagent is stored at -70°C or lower.
1. Cell Attachment Solution, 100-mL: A proprietary reagent used to treat the wells of a 96-well plate prior to planting the cells that promotes rapid cell attachment. Reagent is stored at 15° to 30°C.
1. Growth Medium, 100-mL: Hamm's F-12 cell culture medium containing 10% FBS. Reagent is stored at 20 to 8ºC.
1. Reaction Buffer, 500-mL: A proprietary buffer that augments the reaction of TSI with the TSHR. Reagent is stored at 2º to 8ºC.
1. Control Set:
- Positive Control, 0.5-mL: TSI-containing human serum which yields a value a. that is ≥140% of the Reference Control. Reagent is stored at -70℃ or lower.
- Reference Control, 0.5-mL: A bTSH-containing solution against which b. Controls and Test Specimens are compared. Reagent is stored at -70°C or lower.
- c. Normal Control, 0.5-mL: Human serum that is negative for the presence of TSI which yields a value that is 3.0). If these patients are removed from the dataset from site 3 the PPA increases to 81.5% (95% CI range 70.4% to 89.1%).

Study Site 3-NC is a reference laboratory that receives specimens from all medical disciplines to be tested as part of a thyroid screening panel. The testing of patients with hypothyroidism is more likely in a screening environment than at Sites 1-COH and 2-MN that service targeted disciplines (i.e. Endocrinologists and Thyroidologists). ATA guidelines defines Hypothyroidism as a high TSH level (>3.0). A review of the TSH levels from the three sites indicate a greater percentage of Hypothyroid patients were in fact evaluated at Study Site 3-NC (24% of specimens) than at Study Sites 1-COH and 2-MN (15% and 11%, respectively).

There was good correlation between the three study sites regarding negative percent agreement.

CLINICAL SENSITIVITY AND SPECIFICITY

The Clinical Sensitivity and Specificity for the device was determined by testing 249 characterized specimens. The data is presented in the table 5.8 below.

		Table 5.8: Clinical Sensitivity and Specificity
		Diagnosis
		Positives
(Graves Disease)	Negative
(Other autoimmune
diseases and healthy
controls)	Totals
TSI
Reporter	Positive	46	1	47
	Negative	4	198	202
	Total	50	199

Clinical Sensitivity: 92.0% (46/50) Clinical Specificity: 99.5% (198/199)

CONCLUSION

Evidence presented in the above discussion supports substantial equivalence of the subject device, The Thyretain ™ TSI Reporter BioAssay (TSI Reporter), to KRONUS TSH Receptor Antibody (TRAb) Coated Tube (CT) Assay Kit, a device regulated under 21 CFR $ 866.5870, product code JZO.

l Tahara K., Ban T., Minegishi T., Kohn L.D. Immunoglobulins from Graves' disease patients interact with different sites on TSH receptor/LH-CG receptor chimeras than either TSH or immunoglobulins from idiopathic myxedema patients. Biochem Biophys Res Commun. 1991 Aug 30; 179(1):70-7

DEPARTMENT OF HEALTH & HUMAN SERVICES

Image /page/10/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a stylized eagle with three tail feathers, representing the department's mission to protect the health of all Americans and provide essential human services. The eagle is encircled by the words "DEPARTMENT OF HEALTH & HUMAN SERVICES. USA" in a circular arrangement.

Public Health Service

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

MAY 21 2009

DIAGNOSTIC HYBRIDS Inc c/o Ms. Gail R. Goodrum Vice President of Regulatory Affairs 1055 East State Street Suite 100. Athens, OH 45701

Re: K083391

Trade/Device Name: Thyretain™ TSI Reporter BioAssay Regulation Number: 21 CFR §866.5870 Regulation Name: Thyroid autoantibody immunological test system Regulatory Class: Class II Product Code: JZO Dated: May 7, 2009 Received: May 08, 2009

Dear Ms. Goodrum:

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 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 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 Parts 801 and 809); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); and good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820). 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 advice for your device on our labeling regulation (21 CFR Part 801), please contact the Office of In Vitro Diagnostic Device Evaluation and Safety at (240) 276-0450. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding postmarket surveillance, please contact CDRH's Office of Surveillance and Biometric's (OSB's) Division of Postmarket Surveillance at (240) 276-3474. For questions regarding the reporting of device adverse events (Medical Device Reporting (MDR)), please contact the Division of Surveillance Systems at (240) 276-3464. For more information regarding the reporting of adverse events, please go to http://www.fda.gov/cdrh/mdr/.

You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (240) 276-3150 or at its Internet address http://www.fda.gov/cdrh/industry/support/index.html.

Sincerely vours,

Maria M Chan

Maria M. Chan, Ph.D. Director Division of Immunology and Hematology Devices Office of In Vitro Diagnostic Device Evaluation and Safety Center for Devices and Radiological Health

Enclosure

Indication for Use

510(k) Number (if known): K083391

Device Name: Thyretain ™ TSI Reporter BioAssay

Indication For Use:

Prescription Use ﺮ (21 CFR Part 801 Subpart D)

And/Or

Over the Counter Use (21 CFR Part 801 Subpart C)

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

Concurrence of CDRH, Office of In Vitro Diagnostic Device Evaluation and Safety (OIVD)

Munai m. Chen

Division Sign-Off Office of In Vitro Diagnostic Device Evaluation and Safety .

510(k) _k085391/