K Number
K121951
Device Name
LIAISON FT4 LIAISON CONTROL THYROID 1 LIAISON CONTROL THYROID 2 LIAISON CONTROL THYROID 3
Manufacturer
Date Cleared
2013-04-04

(275 days)

Product Code
Regulation Number
862.1695
AI/MLSaMDIVD (In Vitro Diagnostic)TherapeuticDiagnosticis PCCP Authorized
Intended Use
The DiaSorin LIAISON® FT4 assay is an in vitro chemiluminescent immunoassay intended for the quantitative determination of free thyroxine (FT4) in human serum using the LIAISON® Analyzer. It is intended for use as an aid in the clinical assessment of thyroid status. The DiaSorin LIAISON® Control Thyroid 1, LIAISON® Control Thyroid 2 and LIAISON® Control Thyroid 3 are intended for use as assayed quality control samples to monitor the accuracy and precision of the DiaSorin LIAISON® FT4 assay.
Device Description
The DiaSorin LIAISON® FT4 assay's method for quantitative determination of FT4 is based on the Solid Phase Antigen Linked Technique (SPALT) principle. A T4-protein-conjugate is coated on the magnetic particles (solid phase); a monoclonal antibody is linked to an isoluminol derivative (isoluminol-antibody conjugate). All assay steps and incubations are performed by the LIAISON® Analyzer. Results are determined by a 2 point calibration conversion of the master curve to a working curve. The light signal, and hence the amount of isoluminol-antibody conjugate, is measured by a photomultiplier as relative light units (RLU) and is inversely related to FT4 concentration present in calibrators, patient samples or controls.
More Information

Not Found

No
The description details a standard immunoassay technique and data processing based on calibration curves, with no mention of AI or ML algorithms.

No.
The device is an in vitro diagnostic immunoassay that quantifies free thyroxine (FT4) to aid in the clinical assessment of thyroid status, but it does not directly treat or prevent a disease.

Yes.
The device is intended for the quantitative determination of free thyroxine (FT4) in human serum and is used as an aid in the clinical assessment of thyroid status, which are diagnostic purposes. The control samples are also used to monitor the accuracy and precision of the assay.

No

The device is an in vitro diagnostic immunoassay kit that relies on chemical reactions and a physical analyzer (LIAISON® Analyzer) to determine results. It is not solely software.

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 DiaSorin LIAISON® FT4 assay is an in vitro chemiluminescent immunoassay intended for the quantitative determination of free thyroxine (FT4) in human serum. This directly aligns with the definition of an in vitro diagnostic device, which is used to examine specimens derived from the human body to provide information for diagnostic purposes.
  • Device Description: The description details a laboratory-based assay method (chemiluminescent immunoassay) performed on a specific analyzer (LIAISON® Analyzer) using biological samples (human serum).
  • Performance Studies: The performance studies described (Method Comparison, Reference Range/Expected Values, Reproducibility/Precision, Dilution Linearity, LoB/LoD/LoQ, Interfering Substances, Specificity) are typical studies conducted to validate the performance of an in vitro diagnostic assay.
  • Predicate Device(s): The mention of predicate devices (Roche Elecsys® FT4 and Elecsys® PreciControl Universal) which are known IVD devices further supports that this device falls into the same category.

The DiaSorin LIAISON® FT4 assay is designed to be used outside of the body (in vitro) to analyze a human specimen (serum) to provide information about a person's thyroid status, which is a diagnostic purpose.

N/A

Intended Use / Indications for Use

The DiaSorin LIAISON® FT4 assay is an in vitro chemiluminescent immunoassay (CLIA) intended for the quantitative determination of free thyroxine (FT4) in human serum using the LIAISON® Analyzer. It is intended for use as aid in the clinical assessment of thyroid status.

The DiaSorin LIAISON® Control Thyroid 1, LIAISON® Control Thyroid 2 and LIAISON® Control Thyroid 3 are intended for use as assayed quality control samples to monitor the accuracy and precision of the DiaSorin LIAISON® FT4 assay.

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

CEC, JJX

Device Description

The LIAISON® FT4 assay's method for quantitative determination of FT4 is based on the Solid Phase Antigen Linked Technique (SPALT) principle. A T4-protein-conjugate is coated on the magnetic particles (solid phase); a monoclonal antibody is linked to an isoluminol derivative (isoluminol-antibody conjugate). All assay steps and incubations are performed by the LIAISON® Analyzer.

Results are determined by a 2 point calibration conversion of the master curve to a working curve. The light signal, and hence the amount of isoluminol-antibody conjugate, is measured by a photomultiplier as relative light units (RLU) and is inversely related to FT4 concentration present in calibrators, patient samples or controls.

Mentions image processing

Not Found

Mentions AI, DNN, or ML

Not Found

Input Imaging Modality

Not Found

Anatomical Site

Human serum

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)

Method Comparison: A total of 201 samples were tested by the LIAISON® FT4 assay and a commercially available immunoassay. The method comparison study was performed according to CLSI EP9-A2 guideline.
Passing & Bablok regression analysis was performed on the results across the range of LIAISON® FT4 assay yielding agreement of y =1.0707x - 0.1211, R2 = 0.9633. The 95% confidence intervals for the slope were 1.03 to 1.09 and 95% confidence intervals for the intercept were -0.17 to -0.08 ng/dL.

Reference Range/Expected Values: Human serum samples from 130 apparently healthy adults were tested to determine the reference range for the LIAISON® FT4 assay.
Serum (130): Median 1.08 ng/dL (13.9 pmol/L). Observed 95% Normal Range 0.69 – 1.59 ng/dL (8.93 - 20.4 pmol/L).

Reproducibility/Precision:
20 Day Study Design: A twenty day reproducibility/precision study was performed at DiaSorin Inc. A coded panel comprised of 4 frozen serum samples was prepared by DiaSorin. The LIAISON® Control Thyroid (3 levels) were also tested in the study. The CLSI document EP5-A2 was consultred in the preparation of the testing protocol. The precision panel samples and kit controls were tested on one lot of LIAISON® FT4 assay in two replicates per run, 2 runs per day for 20 operating days for a total of 80 replicate results per sample. The mean, standard deviation, and coefficient of variation (%CV) of the results were computed for each of the tested samples.
Results: Kit Control 1: Mean 1.02, SD 0.08, %CV 7.9%. Kit Control 2: Mean 3.18, SD 0.22, %CV 6.9%. Kit Control 3: Mean 6.59, SD 0.46, %CV 7.0%. Sample 1: Mean 1.19, SD 0.09, %CV 8.0%. Sample 2: Mean 1.90, SD 0.14, %CV 7.5%. Sample 3: Mean 5.56, SD 0.40, %CV 7.1%. Sample 4: Mean 5.72, SD 0.40, %CV 7.1%.

5 Day Study Design: An additional five day precision study was performed at DiaSorin. The sample panel consisted of three frozen serum samples prepared by DiaSorin with FT4 concentrations near medical decision points. The precision panel samples were tested on one lot of LIAISON® FT4 assay in twelve replicates per run, one run per day for 5 operating days for a total of 60 replicate results per sample.
Results: Sample 1 (hypo): Mean 0.851, Total SD 0.08, Total %CV 9.5%. Sample 2 (normal): Mean 1.57, Total SD 0.13, Total %CV 8.6%. Sample 3 (hyper): Mean 3.25, Total SD 0.24, Total %CV 7.5%.

Dilution Linearity: An aliquot of a buffer sample containing phosphate buffered saline (PBS), 5% BSA was spiked with T4 and diluted with the same buffer. This yielded a sample with T4 levels spanning the measuring range of the LIAISON® FT4 assay (0.29 - 7.7 ng/dL). The sample was analyzed by the LIAISON® FT4 assay following CLSI EP6-A. The sample was diluted into ten evenly spaced intervals including the neat sample and tested in four replicates for each dilution on the LIAISON® Analyzer.
Results: The results were analyzed by a linear regression of measured FT4 concentration versus expected FT4. LIAISON® FT4 Assay is linear across the measuring range of the assay (0.29 - 7.7 ng/dL).

Traceability, Stability, Target Values:
Traceability: The LIAISON® FT4 kit calibrators are referenced to an 'in-house'' Primary Reference Standard preparation.
Calibrator Value Assignment: Calibrator concentrations are assigned through an internal procedure. Master standards are prepared from intermediate stock solutions. Concentrations are assigned by testing in 10 different assays against the Primary Reference Standard. The master calibrators are then used to assign values to the kit calibrators using multiple LIAISON® analyzers with several kits calibrators over several runs to determine the target values.
Calibrator Stability: Reagent integral is stable until the expiration date printed on the label when stored as directed and for 2 weeks (14 days) on board the LIAISON® analyzer or opened and stored at 2-8°C. Calibration curve stability was performed and demonstrated that kit performance was acceptable to 2 weeks from calibration.
Control Value Assignment: A minimum of 60 valid test results for each control are used in the range assignment. The LIAISON® Control Thyroid 1, LIAISON® Control Thyroid 2, LIAISON® Control Thyroid 3 are tested on a minimum of 3 LIAISON® Analyzers, using 2 different approved LIAISON® FT4 assay kit lots, at a minimal time period of 3 days. The mean value and the standard deviation (std) is calculated from the test results. The target value of the controls is given by the calculated mean value. The target range is given by the mean value +/- 3 std.
Control Stability: Lyophilized controls are stable until the expiration date shown on the product labeling when stored as instructed. Reconstituted controls are stable for up to 48 hours when stored at 2-8°C. For longer storage periods, control aliquots should be frozen to -20°C.

LoB/LoD/LoQ: Determined according to CLSI EP17-A: Protocols for Determination of Limits of Detection and Limits of Quantitation.
Limit of Blank: ≤ 0.06 nq/dL. Limit of Detection: 0.13 na/dL. Limit of Quantitation: 0.29 ng/dL.

Interfering Substances: Controlled studies of potentially interfering substances showed no interference at the concentration for each substance listed in the LIAISON® FT4 assay. The testing was based on CLSI-EP7-A2.

Specificity: The cross-reactivity of the LIAISON®FT4 assay with substances has been expressed as the ratio of the amount of T4 required to displace 50% of the maximally bound labeled T4 from the anti-T4 antibody, to the amount of the cross-reactant to give the same 50% displacement. Amounts for cross-reactant and analyte are taken from the displacement curve. The ratio of the two amounts as percentage-value is the % cross-reactivity of the cross reactant.
Cross-Reactant % Cross-reactivity: D-T4 100%, 3-iodo-L-Tyrosine 0%, 3,5-diiodo-L-Tyrosine 0%, 3,3',5,5'-tetra-iodothyroacetic acid 0%.

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

Not Found. Key metrics from performance studies were R2, confidence intervals for slope and intercept for method comparison, mean, SD, %CV for reproducibility/precision, LoB, LoD, LoQ, and % cross-reactivity for specificity.

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.

K961489, K090541

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

§ 862.1695 Free thyroxine test system.

(a)
Identification. A free thyroxine test system is a device intended to measure free (not protein bound) thyroxine (thyroid hormone) in serum or plasma. Levels of free thyroxine in plasma are thought to reflect the amount of thyroxine hormone available to the cells and may therefore determine the clinical metabolic status of thyroxine. Measurements obtained by this device are used in the diagnosis and treatment of thyroid diseases.(b)
Classification. Class II.

0

121951

5.0 510(k) SUMMARY

March 25, 2013

SUBMITTED BY:

Kelly R. Sauer Regulatory Affairs Specialist DiaSorin Inc. 1951 Northwestern Avenue P.O. Box 285 Stillwater, MN 55082-0285 Phone (651) 351-5884 Fax (651) 351-5669 Email: kelly.sauer@diasorin.com

· APR 4 2013

DATE PREPARED:

NAME OF DEVICE:

Trade Name:

LIAISON® FT4 LIAISON® Control Thyroid 1 LIAISON® Control Thyroid 2 LIAISON® Control Thyroid 3

Common Names/Descriptions:

Classification Names:

Free Thyroxine Assay

Free Thyroxine Test System: Class II 21 CFR 862.1695; Clinical Chemistry (75) Quality Control Material: Class I, reserved 21 CFR 862.1660; Clinical Chemistry (75)

Product Code:

PREDICATE DEVICE:

Roche Elecsys® FT4 Reference K961489 (assav) Elecsys® PreciControl Universal Reference K090541 (control set)

DEVICE DESCRIPTION:

INTENDED USE:

The DiaSorin LIAISON® FT4 assay is an in vitro chemiluminescent immunoassay (CLIA) intended for the quantitative determination of free thyroxine (FT4) in human serum using the LIAISON® Analyzer. It is intended for use as aid in the clinical assessment of thyroid status.

CEC. JJX

The DiaSorin LIAISON® Control Thyroid 1, LIAISON® Control Thyroid 2 and LIAISON® Control Thyroid 3 are intended for use as assayed quality control samples to monitor the accuracy and precision of the DiaSorin LIAISON® FT4 assay.

Section 5

1

KIT DESCRIPTION:

The LIAISON® FT4 assay's method for quantitative determination of FT4 is based on the Solid Phase Antigen Linked Technique (SPALT) principle. A T4-protein-conjugate is coated on the magnetic particles (solid phase); a monoclonal antibody is linked to an isoluminol derivative (isoluminol-antibody conjugate). All assay steps and incubations are performed by the LIAISON® Analyzer.

Results are determined by a 2 point calibration conversion of the master curve to a working curve. The light signal, and hence the amount of isoluminol-antibody conjugate, is measured by a photomultiplier as relative light units (RLU) and is inversely related to FT4 concentration present in calibrators, patient samples or controls.

COMPARISON TO PREDICATE DEVICE:

The DiaSorin LIAISON FT4 assay is substantially equivalent in principle and performance to the Roche Elecsys® FT4 Test (K961489) which was FDA cleared June 11, 1996.

Table 1: Table of Assay Similarities and Differences
CharacteristicNew Device
LIAISON® FT4Predicate Device
Roche Elecsys® FT4 (K961489)
Intended UseThe DiaSorin LIAISON® FT4
Assay is a chemiluminescent
immunoassay (CLIA) intended
for the quantitative
determination of free thyroxine
(FT4) in human serum using
the LIAISON® Analyzer.Immunoassay for the in vitro
quantitative determination of free
thyroxine in human serum and
plasma. The
electrochemiluminescence
Immunoassay "ECLIA" is
intended for use on Elecsys and
cobas e immunoassay
analyzers.
Indications for UseFor use as an aid in the
clinical assessment of thyroid
statusSame
Measured AnalyteFree thyroxineFree thyroxine
Assay TypeChemiluminescent
ImmunoassayElectrochemiluminescent
immunoassay
CalibrationTwo-point verification of
stored master curve.Same
Reagent Integral
StorageOn-board or in refrigerator@
2-8°CSame
Sample
Handling/ProcessingAutomatedSame
Unit of Measureng/dL or pmol/LSame
Reference rangeSerum 0.69 - 1.59 ng/dL
(8.93 -20.4 pmol/L)Serum 0.93 - 1.70 ng/dL
(12.0 - 21.9 pmol/L)
Measuring range0.29 - 7.7 ng/dL
(3.73 - 99.1 pmol/L)0.023 - 7.77ng/dL
(0.300 - 100.0 pmol/L)
Sample MatrixHuman serumHuman serum and plasma

2

Sample size50µL15µL
Conjugate AntibodyMouse monoclonal
anti-thyroxineSheep polyclonal anti-thyroxine
Assay time17 minutes18 minutes
Open storage
2-8°C2 weeks12 weeks
Open storage
on analyzer2 weeks4 weeks
Calibrators2 levels - Included in integral2 levels - Not included with kit
Controls3 levels2 levels

DiaSorin LIAISON® Control Thyroid 1, LIAISON® Control Thyroid 2, LIAISON® Control Thyroid 3 and Elecsys® PreciControl Universal Similarities and Differences

Table 2: Table of Control Similarities and Differences
CharacteristicNew Device
LIAISON® Control Thyroid 1
LIAISON® Control Thyroid 2
LIAISON® Control Thyroid 3Predicate Device
Elecsys® PreciControl
Universal (K090541)
Intended UseIntended for use as quality
control samples to monitor the
accuracy and precision of the
DiaSorin LIAISON® FT4 assayIntended for use as quality
control of Elecsys®
immunoassays on the Elecsys®
and Cobas® e immunoassay
analyzers
MatrixHuman serumSame
Reagent FormatLyophilizedSame
StorageUnopened store at 2-8° C until
expiration dateSame
LevelsThree concentrations :
Low, medium, highTwo concentrations :
Low and high
Reagent Format4 vials x 5.0 mL each level
Each level provided separately2 vials x 3.0 ml each level
HandlingReconstitue with 5.0 mL
distilled water
and allow to stand 15 minutes
before useReconstitute with 3.0 mL
distilled water
and allow to stand 30 minutes
before use.
Open StorageReconstituted :
48 hours at 2-8° C
For longer storage periods,
frozen to -20 °CReconstituted :
On analyzer at 20-25° C up to 5
hrs ; 3 days at 2-8° C;
-20° C for up to 1 month

:

3

PERFORMANCE DATA:

Method Comparison:

A total of 201 samples were tested by the LIAISON® FT4 assay and a commercially available immunoassay. The method comparison study was performed according to CLSI EP9-A2 guideline.

Passing & Bablok regression analysis was performed on the results across the range of LIAISON® FT4 assay yielding agreement of y =1.0707x - 0.1211, R2 = 0.9633. The 95% confidence intervals for the slope were 1.03 to 1.09 and 95% confidence intervals for the intercept were -0.17 to -0.08 ng/dL.

Reference Range/Expected Values:

Human serum samples from 130 apparently healthy adults were tested to determine the reference range for the LIAISON® FT4 assay.

Apparently Healthy AdultsMedianObserved 95% Normal Range
Serum (130)1.08 ng/dL0.69 — 1.59 ng/dL
13.9 pmol/L8.93 - 20.4 pmol/L
Consider these limits as guidelines only. Each laboratory should establish its own reference range

Reproducibility/Precision:

20 Day Study Design

A twenty day reproducibility/precision study was performed at DiaSorin Inc. A coded panel comprised of 4 frozen serum samples was prepared by DiaSorin. The LIAISON® Control Thyroid (3 levels) were also tested in the study. The CLSI document EP5-A2 was consultred in the preparation of the testing protocol.

The precision panel samples and kit controls were tested on one lot of LIAISON® FT4 assay in two replicates per run, 2 runs per day for 20 operating days for a total of 80 replicate results per sample.

The mean, standard deviation, and coefficient of variation (%CV) of the results were computed for each of the tested samples.

Results:

The 20 day results are summarized in Table 3 as sample overall mean FT4 concentration in ng/dL, computed SDs and %CVs for between run and total.

4

MeanBetween RunTOTAL
SampleN(ng/dL)SD%CVSD%CV
Kit Control 1801.020.021.8%0.087.9%
Kit Control 2803.180.072.3%0.226.9%
Kit Control 3806.590.334.9%0.467.0%
Sample 1801.190.032.7%0.098.0%
Sample 2801.900.052.4%0.147.5%
Sample 3805.560.173.1%0.407.1%
Sample 4805.720.172.9%0.407.1%

Table 3: Reproducibility/Precision Results - 20 day

5 Day Study Design

An additional five day precision study was performed at DiaSorin. The sample panel consisted of three frozen serum samples prepared by DiaSorin with FT4 concentrations near medical decision points.

The precision panel samples were tested on one lot of LIAISON® FT4 assay in twelve replicates per run, one run per day for 5 operating days for a total of 60 replicate results per sample.

Results:

The 5 day results are summarized in Table 4 as sample overall mean FT4 concentration in ng/dL, computed SDs and %CVs for between run and total.

| Sample | N | Mean (ng/dL) | Between Run
SD | Between Run
%CV | TOTAL
SD | TOTAL
%CV |
|-------------------|----|--------------|-------------------|--------------------|-------------|--------------|
| Sample 1 (hypo) | 60 | 0.851 | 0.08 | 9.7 | 0.08 | 9.5% |
| Sample 2 (normal) | 60 | 1.57 | 0.14 | 9.0 | 0.13 | 8.6% |
| Sample 3 (hyper) | 60 | 3.25 | 0.24 | 7.4 | 0.24 | 7.5% |

Table 4: Reproducibility/Precision Results - 5 day

Dilution Linearity:

An aliquot of a buffer sample containing phosphate buffered saline (PBS), 5% BSA was spiked with T4 and diluted with the same buffer. This yielded a sample with T4 levels spanning the measuring range of the LIAISON® FT4 assay (0.29 - 7.7 ng/dL). The sample was analyzed by the LIAISON® FT4 assay following CLSI EP6-A. The sample was diluted into ten evenly spaced intervals including the neat sample and tested in four replicates for each dilution on the LIAISON® Analyzer.

Results:

The results were analyzed by a linear regression of measured FT4 concentration versus expected FT4. The resulting regression equation:

5

LIAISON® FT4 Assay is linear across the measuring range of the assay (0.29 - 7.7 ng/dL).

Traceability, Stability, Target Values:

Traceability: The LIAISON® FT4 kit calibrators are referenced to an 'in-house'' Primary Reference Standard preparation.

Calibrator Value Assignment: Calibrator concentrations are assigned through an internal procedure. Master standards are prepared from intermediate stock solutions. Concentrations are assigned by testing in 10 different assays against the Primary Reference Standard. The master calibrators are then used to assign values to the kit calibrators using multiple LIAISON® analyzers with several kits calibrators over several runs to determine the target values.

Calibrator Stability: Reagent integral is stable until the expiration date printed on the label when stored as directed and for 2 weeks (14 days) on board the LIAISON® analyzer or opened and stored at 2-8°C.

Calibration curve stability was performed and demonstrated that kit performance was acceptable to 2 weeks from calibration.

LIAISON® FT4 Calibrator 1 is manufactured to have a FT4 level between 0.45 - 0.55 ng/dL. LIAISON® FT4 Calibrator 2 is manufactured to have a FT4 level between 5.0 – 7.0 ng/dL.

Control Value Assignment: A minimum of 60 valid test results for each control are used in the range assignment. The LIAISON® Control Thyroid 1, LIAISON® Control Thyroid 2, LIAISON® Control Thyroid 3 are tested on a minimum of 3 LIAISON® Analyzers, using 2 different approved LIAISON® FT4 assay kit lots, at a minimal time period of 3 days. The mean value and the standard deviation (std) is calculated from the test results. The target value of the controls is given by the calculated mean value. The target range is given by the mean value +/- 3 std.

Control Stability: Lyophilized controls are stable until the expiration date shown on the product labeling when stored as instructed.

Reconstituted controls are stable for up to 48 hours when stored at 2-8°C. For longer storage periods, control aliquots should be frozen to -20°C.

LIAISON® Control Thyroid 1 has a target value of 1.0 ng/dL LIAISON® Control Thyroid 2 has a target value of 3.0 ng/dL LIAISON® Control Thyroid 3 has a target value of 6.0 ng/dL

6

LoB/LoD/LoQ

The Limit of Blank, Limit of Detection and Limit of Quantitation were determined according to CLSI EP17-A: Protocols for Determination of Limits of Detection and Limits of Quantitation.

The following limits were determined with the LIAISON® FT4 assay:

Limit of Blank: ≤ 0.06 nq/dL Limit of Detection: 0.13 na/dL Limit of Quantitation: 0.29 ng/dL

Interfering Substances

Controlled studies of potentially interfering substances showed no interference at the concentration for each substance listed below in the LIAISON® FT4 assay. The testing was based on CLSI-EP7-A2.

| Substance/Drug | Concentration
Tested |
|----------------------------------------------------------|-------------------------|
| Hemoglobin | 1000 mg/dL |
| Triglycerides | 3000 mg/dL |
| Bilirubin (conj) | 20 mg/dL |
| Bilirubin (unconj) | 20 mg/dL |
| Salicylic acid | 741300 ng/dL |
| Acetylsalicylic acid | 907200 ng/dL |
| Phenylbutazone | 1540500 ng/dL |
| Diphenylhydantoin | 1301397 ng/dL |
| Amiodarone | 3396600 ng/dL |
| 8-Anilino-1-naphtalene
sulfonic acid
ammonium salt | 1579200 ng/dL |
| Furosemide | 1626000 ng/dL |
| Iopanic acid | 2842000 ng/dL |
| DL-propranolol | 1520000 ng/dL |
| Rheumatoid Factor | 54 IU/mL |

Specificity

The cross-reactivity of the LIAISON®FT4 assay with these substances has been expressed where possible as the ratio of:

  • The amount of the T4 required to displace 50% of the maximally bound labeled T4 from . the anti-T4 antibody,
  • The amount the cross-reactant to give the same 50% displacement. .

Amounts for cross-reactant and analyte are taken from the displacement curve. The ratio of the two amounts as percentage-value is the % cross-reactivity of the cross reactant.

7

Cross-Reactant% Cross-reactivity
D-T4100%
3-iodo-L-Tyrosine0%
3,5-diiodo-L-Tyrosine0%
3,3',5,5'-tetra-iodothyroacetic acid0%

CONCLUSION:

The material submitted in this premarket notification is complete and supports the basis for substantial equivalence. The labeling is sufficient and satisfies the requirements of 21 CFR Part 809.10.

8

DEPARTMENT OF HEALTH & HUMAN SERVICES

Image /page/8/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a stylized depiction of an eagle or bird-like figure with three curved lines representing its wings or body. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" is arranged in a circular fashion around the bird-like figure.

Public Health Service

Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002

April 4, 2013

KELLY R SAUER REGULATORY AFFAIRS SPECIALIST DIASORIN 1951 NORTHWESTERN AVE. P.O. BOX 285 STILLWATER MN 55082

Re: K121951

Trade/Device Name: LIAISON® FT4, LIAISON® Control Thyroid 1, LIAISON® Control Thyroid 2, LIAISON® Control Thyroid 3

Regulation Number: 21 CFR 862.1695 Regulation Name: Free thyroxine test system Regulatory Class: II Product Code: CEC, JJX Dated: March 25, 2013 Received: March 28, 2013

Dear Ms. Sauer:

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. Ilisting 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 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 Parts 801 and 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.

9

If you desire specific advice for your device on our labeling regulations (21 CFR Parts 801 and 809), please contact the Office of In Vitro Diagnostics and Radiological Health at (301) 796-5450. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR 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 the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

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 (301) 796-7100 or at its Internet address http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm.

Sincerely yours.

Carol C. Benson -S for

Courtney H. Lias, Ph.D.

Director, Division of Chemistry and Toxicology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health

Enclosure

10

Indications for Use

510(k) Number (if known): K121951

Device Name: LIAISON® FT4 LIAISON® Control Thyroid 1, LIAISON® Control Thyroid 2 LIAISON® Control Thyroid 3

Indications for Use:

The DiaSorin LIAISON® FT4 assay is an in vitro chemiluminescent immunoassay intended for the quantitative determination of free thyroxine (FT4) in human serum using the LIAISON® Analyzer. It is intended for use as an aid in the clinical assessment of thyroid status.

The DiaSorin LIAISON® Control Thyroid 1, LIAISON® Control Thyroid 2 and LIAISON® Control Thyroid 3 are intended for use as assayed quality control samples to monitor the accuracy and precision of the DiaSorin LIAISON® FT4 assay

Prescription Use X (21 CFR Part 801 Subpart D) And/Or

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

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Concurrence of CDRH, Office of In Vitro Diagnostics and Radiological Health (OIR)

YungW.DChan -S

Division Sign-Off Office of In Vitro Diagnostics and Radiological Health

510(k) K121951

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