(80 days)
The IMMULITE® 2000 Free Thyroxine Assay is for in vitro diagnostic use with the IMMULITE 2000 Systems Analyzers - for the quantitative measurement of nonprotein-bound thyroxine (free T4) in serum and heparinized plasma, as an aid in the clinical assessment of thyroid status.
The IMMULITE 2000 Free T4 is a solid-phase, enzyme-labeled chemiluminescent competitive immunoassay. The solid phase (bead) is coated with monoclonal murine anti-T4 antibody. The liquid phase consists of alkaline phosphatase (bovine calf intestine) conjugated to T4. The patient sample and the reagent are incubated together with the coated bead for 30 minutes. During this time, free T4 in the sample competes with enzyme coniugated T4 in the buffer for a limited number of antibody binding sites on the bead. Unbound patient sample and enzyme conjugate are then removed by centrifugal washes. Finally, the chemiluminescent substrate is added to the reaction tube containing the bead and the signal is generated in proportion to the bound enzyme. The IMMULITE 2000 Free T4 procedure is a direct or single test assay, in the sense that its results are not calculated as a function of total T4, but interpolated from a (stored) standard curve calibrated in terms of free T4 concentrations.
Here's a breakdown of the acceptance criteria and study information for the IMMULITE® 2000 Free T4 assay, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Performance Metric | Acceptance Criteria (Implied / Predicate) | Reported IMMULITE 2000 Free T4 Performance |
|---|---|---|
| Reportable Range | N/A (Compared to predicate) | 0.3 - 6.0 ng/dL |
| Analytical Sensitivity | ||
| - Limit of Blank (LoB) | N/A (Determined per CLSI EP17-A) | 0.05 ng/dL |
| - Limit of Detection (LoD) | N/A (Determined per CLSI EP17-A) | 0.13 ng/dL |
| - Functional Sensitivity | N/A (Defined as 20% CV) | 0.25 ng/dL |
| Linearity/Recovery | Excellent Goodness-of-Fit (R² close to 1) | R² = 0.995; Average % Recovery = 103% |
| Precision (Total CV) | N/A (Compared to predicate's 2.73-6.56%) | 3.6% @ 2.91 ng/dL to 10.2% @ 0.51 ng/dL |
| Endogenous Interference | No significant interference | Bilirubin (up to 20 mg/dL): No effectHemoglobin (up to 634 mg/dL): No effectTriglycerides (up to 1000 mg/dL): No effect |
| Accuracy / Correlation (vs. Predicate) | High correlation (r close to 1) | Y = 1.06x - 0.001; r = 0.981 |
| Cross-Reactivity | No detectable cross-reactivity | No detectable cross-reactivity to listed compounds (L-T3, etc.) |
| Assay Kit Shelf Life | N/A | 330 days (unopened at 2-8°C) |
| On-Board Reagent Stability | N/A | 92 days |
| Adjustors/Controls Open Vial Stability | N/A | 30 days (2-8°C) or 6 months (aliquoted at -20°C) after reconstitution |
Note on Acceptance Criteria: For many analytical performance characteristics (like linearity, precision, sensitivity, and interference), the "acceptance criteria" are implied by adherence to CLSI guidelines and demonstrating performance comparable to or better than established methods/predicate devices. Specific numerical thresholds for acceptance, beyond what is reported as achieved, are not explicitly stated. The primary acceptance criterion for the overall device's substantial equivalence is its performance relative to the predicate device in terms of accuracy/correlation and other analytical characteristics.
2. Sample Sizes Used for the Test Set and Data Provenance
- Accuracy/Correlation (Method Comparison):
- Sample Size: 282 samples
- Data Provenance: Not explicitly stated, but based on a "Method Comparison" against a predicate device, it implies prospective testing of patient or control samples using both devices. The origin country is not specified.
- Precision:
- Sample Size: Six different material/sample pools (Pool 05-09 and Control). For each, two aliquots were assayed in two runs per day on 20 different days. This amounts to 80 measurements per material (2 aliquots * 2 runs/day * 20 days).
- Data Provenance: Not explicitly stated, but typically generated in a controlled laboratory setting (e.g., at Siemens Healthcare Diagnostics).
- Linearity/Recovery:
- Sample Size: 9 samples (calibrators and mixed calibrators). Five replicates of each sample were assayed.
- Data Provenance: Laboratory generated.
- Interference (Endogenous & Cross-Reactivity):
- Sample Size: Not specified for how many samples or replicates were tested for each interferent, but implies a series of controlled experiments.
- Data Provenance: Laboratory generated.
- Limit of Blank (LoB) & Limit of Detection (LoD):
- Sample Size: Not explicitly stated, but guided by CLSI EP17-A.
- Data Provenance: Laboratory generated.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
- This device is an in vitro diagnostic (IVD) assay for quantitative measurement of Free T4, not an imaging or diagnostic AI tool that requires expert interpretation of images/data for ground truth.
- The "ground truth" for the test set (e.g., the true Free T4 concentration for method comparison, linearity, or precision) would be established by:
- Using reference materials with known concentrations.
- Performance of the predicate device (ADVIA Centaur FrT4) for comparison studies.
- Validated analytical methods as performed by laboratory professionals.
- Therefore, the concept of "number of experts used to establish ground truth" as it applies to subjective interpretation (like radiology reads) is not directly relevant here. Instead, it relies on the analytical accuracy and precision of established methods and technical expertise in laboratory testing and calibration.
4. Adjudication Method for the Test Set
- Not applicable as this is an IVD assay, not an AI diagnostic tool requiring subjective interpretation and adjudication. The "ground truth" for method comparison is the measurement by the predicate device (ADVIA Centaur FrT4).
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was Done
- No, an MRMC comparative effectiveness study was not done. This is an in vitro diagnostic assay measuring a biochemical marker, not a system that relies on human readers interpreting medical cases.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was Done
- Yes, the performance presented (e.g., precision, linearity, sensitivity, method comparison) is standalone performance of the IMMULITE 2000 Free T4 assay system (analyzer, reagents, and calibration software) without human-in-the-loop interpretation beyond standard laboratory procedures for running the assay and reviewing results. The "algorithm" here refers to the immunoassay chemistry and the instrument's computational processing of chemiluminescent signals to produce a quantitative result.
7. The Type of Ground Truth Used
The ground truth for the various performance studies can be categorized as:
- Predicate Device Measurements: For the accuracy/correlation (method comparison) study, the measurements from the ADVIA Centaur FrT4 assay served as the comparative 'ground truth'.
- Known Concentrations/Reference Materials: For linearity/recovery, limit of blank, and limit of detection, the ground truth was established using calibrators, known dilutions, or samples expected to contain no analyte, where the "true" concentrations are precisely defined.
- Statistical Definitions: Functional sensitivity is defined by a specific statistical criterion (20% CV), rather than an external "ground truth" measurement.
8. The Sample Size for the Training Set
- This document describes the validation of an immunoassay kit for an existing instrument platform (IMMULITE 2000). It is not an AI/machine learning device in the sense of requiring a "training set" of data for algorithm development. The assay's "learning" or calibration involves using specific calibrator materials with known concentrations to generate a standard curve, which is distinct from an AI training set. Therefore, this concept is not applicable here.
9. How the Ground Truth for the Training Set Was Established
- As stated above, the concept of a "training set" for an AI algorithm is not applicable to this immunoassay device. The assay is calibrated using calibrators with precisely known concentrations of Free T4. The "ground truth" for these calibrators would be established through highly accurate reference methods or certified reference materials.
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SUMMARY OF SAFETY AND EFFECTIVENESS
Assigned 510(k) Number 1.1
The assigned 510(k) number is _k 083373
1.2 Sponsor Name and Address
Siemens Healthcare Diagnostics (formerly Siemens Medical Solutions Diagnostics) 511 Benedict Avenue Tarrytown, NY 10591
1.3 Contact
Philip Liu, Ph.D. Manager, Regulatory Affairs & Compliance (914) 524-2443 philip.liu@siemens.com
1.4 Device Name
| Trade Name: | IMMULITE® 2000 Free T4 |
|---|---|
| Common Name: | Free Thyroxine |
| Classification: | Class II device CEC 21 CFR 862.1695 |
| Catalog Numbers: | L2KFT42 (200 tests), L2KFT43M (3000 tests),L2KFT46 (600 tests), L2KFT46M (6000 tests) |
1.5 Description of Device
The IMMULITE 2000 Free T4 is a solid-phase, enzyme-labeled chemiluminescent competitive immunoassay. The solid phase (bead) is coated with monoclonal murine anti-T4 antibody. The liquid phase consists of alkaline phosphatase (bovine calf intestine) conjugated to T4.
The patient sample and the reagent are incubated together with the coated bead for 30 minutes. During this time, free T4 in the sample competes with enzyme coniugated T4 in the buffer for a limited number of antibody binding sites on the bead. Unbound patient sample and enzyme conjugate are then removed by centrifugal washes. Finally, the chemiluminescent substrate is added to the reaction tube containing the bead and the signal is generated in proportion to the bound enzyme.
The IMMULITE 2000 Free T4 procedure is a direct or single test assay, in the sense that its results are not calculated as a function of total T4, but interpolated
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from a (stored) standard curve calibrated in terms of free T4 concentrations.1 In this respect it differs from so-called free T4 index determinations. Unlike the classic equilibrium dialysis methods, it requires neither a pre-incubation step nor preliminary isolation of the free fraction by dialysis or column chromatography.
Incubation Cycles: 1 x 30 minutes Time to First Result: 35 minutes
Indications for Use 1.6
IMMULITE® 2000 Free T4 assay is intended for use as follows:
For in vitro diagnostic use with the IMMULITE 2000 Systems Analyzers - for the quantitative measurement of non-protein-bound thyroxine (free T4) in serum and heparinized plasma, as an aid in the clinical assessment of thyroid status.
1.7 Manufacturing Site
IMMULITE 2000 Free T4 assay is manufactured at the following locations:
Siemens Healthcare Diagnostics (formerly Siemens Medical Solutions Diagnostics) 5700 West 96th Street Los Angeles, CA 90045-5597 FDA Establishment #: 2017183
Siemens Healthcare Diagnostics (formerly Siemens Medical Solutions Diagnostics) 5210 Pacific Concourse Drive Los Angeles, CA 90045-6900 FDA Establishment #: 3005250747
1.8 Comparison to the Predicate
The IMMULITE 2000 Free T4 assay was cleared with the IMMULITE 2000 instrument (K970227) and predicated on the IMMULITE Free T4 assay (K971792). The revised IMMULITE 2000 Free T4 assay, described in this submission, is predicated on the Siemens Healthcare Diagnostics ADVIA Centaur Free T4 (FrT4) assay (K961510/K971418).
A summary of the features of the IMMULITE 2000 Free T4 assay and the predicate device ADVIA Centaur FrT4 is presented below.
1 Wosilait WD. A theoretical analysis of the distribution of thyroxine among sites on thyroid binding globulin, thyroid binding prealbumin and serum albumin. Res Commun Chem Pathol Pharmacol 1977;16:541-8.
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Performance of the IMMULITE 2000 Free T4 assay was determined in analytical performance validation studies and in method comparison studies comparing the IMMULITE 2000 Free T4 with the predicate device.
.
| IMMULITE 2000 FREE T4Immunoassay(Device) | ADVIA Centaur FrT4Immunoassay(Predicate) | |
|---|---|---|
| Indications for Use | For the quantitative measurement ofnon-protein-bound thyroxine (freeT4) in serum, as an aid in theclinical assessment of thyroidstatus. | For in vitro diagnostic use in thequantitative determination of freethyroxine (Fr T4) |
| Sample Type (s) | Serum and plasma | Serum |
| Assay Type | One-cycle immunoassay | One-cycle immunoassay |
| Cycle1 Incubation | Anti-T4 Mab (on ¼" bead) + serumFT4 + T4-Alkaline Phosphatase | Lite reagent (T4- acridinium ester) +serum FT4 + solid phase (anti-T4Polyclonal antibody onmicroparticles) |
| Incubation time | 30 minutes | 7.5 minutes |
| Sample Volume | 10 uL | 25 uL |
| Reportable range | 0.3 - 6.0 ng/dL | 0.1 - 12.0 ng/dL |
| Analytical Sensitivity | LoB = 0.05 ng/dLLoD = 0.13 ng/dLFunctional Sensitivity = 0.25 ng/dL | Minimum Detectable Concentrationof 0.1 ng/dL |
| Precision (Total) | 10.2%@ 0.51 ng/dL6.4% @ 1.13 ng/dL3.6% @ 2.91 ng/dL | 6.56%@ 0.47 ng/dL3.03% @ 1.08 ng/dL2.73% @ 3.09 ng/dL |
| EndogenousInterference | No significant interference fromconjugated/unconjugated bilirubin(up to 20 mg/dL), hemoglobin (up to634 mg/dL) or triglycerides (up to1000 mg/dL). | No significant interference fromconjugated bilirubin (up to 20mg/dL), hemoglobin (up to 300mg/dL) or triglycerides (up to 1000mg/dL). |
| Accuracy / Correlation(Serum) | Y = 1.06x - 0.001r = 0.981(vs. ADVIA Centaur FrT4) | Y = 0.99x + 0.02r = 0.99(vs. ACS:180 FrT4) |
:
Siemens Healthcare Diagnostics (formerly Slemens Medical Solutions Diagnostics) IMMULITE 2000 Free T4 510K
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Expected Results 1.9
The expected results for the IMMULITE 2000 Free T4 assay are based on the established ranges of the ADVIA Centaur Free T4 assay (Predicate Device). Ranges for the ADVIA Centaur FrT4 assay were established using serum obtained from 388 apparently healthy individuals. Serum was analyzed with the ACS: 180° FrT4 assay and confirmed for the ADVIA Centaur FrT4 assay by analyzing 283 samples in the range of 0.14- 11.1 ng/dL (1.81 to 143 pmol/L). Expected results are as follows:
| Clinical Condition | FT4 Range (ng/dL) | FT4 Range (pmol/L |
|---|---|---|
| Euthyroid | 0.89 - 1.76 | 11.5 - 22.7 |
| Hypothyroid | less than 0.89 | less than 11.5 |
| Hyperthyroid | greater than 1.76 | Greater than 22.7 |
As with all in vitro diagnostic assays, each laboratory should determine its own reference range(s) for the diagnostic evaluation of patient results.
1.10 Reportable Range
The IMMULITE 2000 Free T4 is a quantitative assay with a reportable range from 0.3 to 6 ng/dL (3.9 to 77.2 pmol/L).
Limit of Blank 1.11
The determination of Limit of Blank was quided by Clinical Laboratory Standards Institute (CLSI): Protocols for Determination of Limits of Detection and Limits of Quantitation; Approved Guideline. CLSI document EP17-A (ISBN 1-56238-551-8).
This guideline defines Limit of Blank (LoB) as the highest value expected to be seen in a series of results for samples that contain no analyte.
The LoB claim for the IMMULITE 2000 Free T4 is 0.05 ng/dL.
1.12 Limit of Detection
The determination of Limit of Detection was guided by Clinical Laboratory Standard Institute (CLSI): Protocols for Determination of Limits of Detection and Limits of Quantitation; Approved Guideline. CLSI document EP17-A (ISBN 1-56238-551-8).
This guideline defines the Limit of Detection (LoD) as the actual concentration at which an observed test result is likely to exceed the Limit of Blank (LoB) and may therefore be declared as detected.
The LoD claim for the IMMULITE 2000 Free T4 is 0.13 ng/dL.
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1.13 Functional Sensitivity
The concentration with a 20% coefficient of variation for the IMMULITE 2000 Free T4 is 0.25 ng/dL. This is the functional sensitivity of this assay.
1.14 Linearity/Recovery
Linearity/recovery was evaluated by assaving as unknowns the calibrators and calibrators mixed 1:1 to create intermediate values. Five (5) replicates of each sample were assayed. The mean observed/expected values were calculated. Average % recovery across 9 samples tested was 103%.
Linear regression of Observed versus Expected doses demonstrated excellent Goodness-of-Fit (R2 = 0.995) with the following equation:
Observed = 0.97(Expected) + 0.062
1.15 Precision
Precision studies were performed in accordance with Clinical Laboratory Standard Institute (CLSI) quidance: Evaluation of Precision Performance of Quantitative Methods; Approved Guideline-Second Edition. CLSI document EP5-A2 (ISBN 1-56238-542-9). Two aliquots of each test sample were assayed in two runs per day on 20 different days. Analysis of variance was used to estimate the within-run and total variance.
Precision results for the IMMULITE 2000 Free T4 assay are as follows:
| Material / Sample # | Mean(ng/dL) | Within-Run | Total | ||
|---|---|---|---|---|---|
| SD (ng/dL) | CV % | SD (ng/dL) | CV % | ||
| Pool 05 | 0.51 | 0.040 | 7.8 | 0.052 | 10.2 |
| Pool 06 | 0.85 | 0.038 | 4.5 | 0.060 | 7.1 |
| Control | 1.13 | 0.067 | 5.9 | 0.072 | 6.4 |
| Pool 07 | 1.49 | 0.072 | 4.8 | 0.090 | 6.0 |
| Pool 08 | 2.91 | 0.103 | 3.5 | 0.104 | 3.6 |
| Pool 09 | 4.82 | 0.144 | 3.0 | 0.172 | 3.6 |
IMMULITE 2000 Free T4 Precision*
- Data are representative of one lot on one instrument
1.16 Assay Specificity
1.16.1 Potential Interferents
The IMMULITE 2000 Free T4 assay was tested for interference by bilirubin, hemoglobin and triglycerides.
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Presence of conjugated or unconjugated billirubin in concentrations up to 20 mg/dL has no effect on the results of the assay.
Presence of hemoglobin in concentrations up to 634 mg/dL has no effect on the results of the assay.
Presence of triglycerides in concentrations up to 1000 mg/dL has no effect on the results of the assay.
1.16.2 CROSS-REACTIVITY
The IMMULITE 2000 Free T4 assay is highly specific for Free T4 with no detectable cross-reactivity to other naturally occurring compounds that might be present in patient samples, including L-T3, Diiodothyronine, Monoiodotyrosine, Diiodotyrosine, D-T4, Diphenylhydantoin (Phenytoin), Tetraiodothyroacetic Acid, Salicylic Acid, and Albumin.
1.17 Quality Control
The recommended control is the Siemens Medical Solutions Diagnostics' CON6 Multivalent Control Module. This control is a multi-constituent, human serumbased, tri-level containing over 25 constituents commonly measured by immunoassay. It is intended strictly for in vitro diagnostic use as an aid in monitoring the day-to-day performance of assays for these constituents.
Sample Stability 1.18
Samples are stable for 2 days at 2-8°C, or 2 months frozen at -20°C2
1.19 Assay Kit Stability
1.19.1 SHELF LIFE
Kit stability testing was conducted on multiple lots of the IMMULITE 2000 Free T4 assay kit and included the following assessments:
- Real-time stability at long term package insert storage conditions .
- Stress (accelerated) conditions to simulate storage/stress conditions . that might occur during shipment to and storage at customer facilities. Stress studies also support real-time stability. Stress studies indicated below were conducted at initiation of the stability testing and repeafed a minimum of 90 days later.
- 3-Day storage at 37°C o
- o 7-Dav storage at room temperature (15-30°C)
- o 3 Freeze/thaw cycles (freeze -30°C to -5°C, thaw at 2-8°C)
2 Hay ID, Bayer MF, et al. American Thyroid Association assessment of current free thyroid hormone and thyrotropin measurements and guidelines for future clinical assays. Clin Chem 1991:37:2002-8.
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The shelf life claim for the IMMULITE 2000 Free T4 assay kit is 330 days (unopened) when stored at 2-8°C.
1.19.2 ON-BOARD REAGENT STABILITY
The Free T4 reagent is stable on-board the IMMULITE 2000 instrument after opening for 92 days.
1.19.3 ASSAY ADJUSTORS AND CONTROLS OPEN VIAL STABILITY
IMMULITE 2000 Free T4 Adjustors and Controls are stable at 2-8°C for 30 days or for 6 months (aliquoted) at -20 ℃ after reconstitution.
1.20 Method Comparison - Comparison of IMMULITE 2000 Free T4 to the Predicate Assay
Free T4 results of 282 samples were compared between IMMULITE 2000 Free T4 and the Predicate assay. Results indicate substantial equivalence.
IMMULITE 2000 (Y) vs. ADVIA Centaur FrT4 (X):
Linear Regression:
Y= 1.06X - 0.001;
Slope = 1.06 (95% Cl 1.03 to 1.08);
Intercept = - 0.001 (95% CI -0.04 to 0.04); r = 0.981
| Mean IMMULITE 2000 Free T4: | 1.43 ng/dL |
|---|---|
| Mean ADVIA Centaur FrT4 | 1.35 ng/dL |
| Sample range | 0.3 - 5.2 ng/dL |
1.21 Conclusions
The IMMULITE 2000 Free T4 assay demonstrates acceptable analytical performance including analytical sensitivity, precision, analytical specificity, and accuracy. Method comparison to the predicate demonstrated acceptable regression statistics and agreement of reference intervals. The IMMULITE 2000 Free T4 assay is therefore substantially equivalent to the FDA cleared predicate ADVIA Centaur FrT4 and thereby safe and effective for the following intended use:
For in vitro diagnostic use with the IMMULITE 2000 Systems Analyzers for the quantitative measurement of non-protein-bound thyroxine (free T4) in serum and heparinized plasma as an aid in the clinical assessment of thyroid status.
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DEPARTMENT OF HEALTH & HUMAN SERVICES
Image /page/7/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a stylized eagle with its wings spread, and the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" is arranged in a circular pattern around the eagle. The eagle is black, and the text is also black. The logo is simple and recognizable.
Public Health Service
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
FEB -2 2009
Siemens Healthcare Diagnostics c/o Philip Liu, Ph.D. Manager, Regulatory Affairs and Compliance 511 Benedict Ave. Tarrytown, NY 10591
Re: K083373
Trade Name: IMMULITE 2000 Free Thyroxine Assay · Regulation Number: 21 CFR 862.1695 Regulation Name: Free Thyroxine Test System Regulatory Class: Class II Product Codes: CEC Dated: November 11, 2008 Received: November 14, 2008
Dear Dr. Liu:
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); and good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820).
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Page - 2
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 information about the application of labeling requirements to your device, or questions on the promotion and advertising of your device, please contact the Office of In. Vitro Diagnostic Device Evaluation and Safety at (301) 594-3084. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97), 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) 443-6597 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html.
Sincerely yours,
Cory C. H.
Courtney C. Harper, Ph.D. Acting Director Division of Chemistry and Toxicology Office of In Vitro Diagnostic Device Evaluation and Safety Center for Devices and Radiological Health
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Indication for Use
510(k) Number (if known): ¡¢ 0 9 3 3 7 3
Device Name: IMMULITE® 2000 Free Thyroxine Assay
Indication For Use:
The IMMULITE® 2000 Free Thyroxine Assay is for in vitro diagnostic use with the IMMULITE 2000 Systems Analyzers - for the quantitative measurement of nonprotein-bound thyroxine (free T4) in serum and heparinized plasma, as an aid in the clinical assessment of thyroid status.
Prescription Use X (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)
Carol C Benson
Division Sign-Off Office of In Vitro Diagnostic Device Evaluation and Safety
510(k) K083373
Page 1 of 1 .
§ 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.