K Number
K202826
Date Cleared
2021-01-15

(113 days)

Product Code
Regulation Number
862.1205
Reference & Predicate Devices
Predicate For
N/A
AI/MLSaMDIVD (In Vitro Diagnostic)TherapeuticDiagnosticis PCCP AuthorizedThirdpartyExpeditedreview
Intended Use

For in vitro diagnostic use with the IMMULITE® 2000 Systems Analyzers — for the quantitative measurement of cortisol (hydrocortisone, Compound F) in serum, as an aid in the clinical assessment of adrenal status.

Device Description

The IMMULITE 2000 Cortisol assay is comprised of the following components: Cortisol Bead Pack (solid phase) containing Polyclonal rabbit anti-cortisol antibody; Cortisol Reagent Wedge (liquid phase) containing Alkaline phosphatase (bovine calf intestine) conjugated to cortisol in buffer, with preservative; and Cortisol Adjustors (Low and High) containing Cortisol in processed human serum, with preservative.

AI/ML Overview

The provided document describes the IMMULITE® 2000 Cortisol device, a chemiluminescence immunoassay for the quantitative measurement of cortisol in serum, used as an aid in the clinical assessment of adrenal status. This submission (K202826) is for a modified device due to a new supplier of the antibody, with the predicate device being the IMMULITE® 2000 Cortisol (K931409).

Here's an analysis of the acceptance criteria and the study that proves the device meets them, based on the provided text:

Executive Summary:

The study aims to demonstrate substantial equivalence of the modified IMMULITE® 2000 Cortisol assay to the predicate device. The performance characteristics evaluated included detection limits, linearity, precision, spike recovery, method comparison, and analysis of interfering and cross-reactive substances. All evaluated studies produced acceptable results compared to the predicate device.


1. Table of Acceptance Criteria and Reported Device Performance:

The document doesn't explicitly state "acceptance criteria" for each performance characteristic in a quantifiable manner (e.g., "linearity must have an R-squared > 0.98"). Instead, it states that the studies "produced acceptable results when compared to the Predicate device and were deemed verified" or that information "has not changed and are as per K931409." For method comparison, a regression equation and correlation coefficient are provided.

Performance CharacteristicAcceptance Criteria (Implied / Predicate Reference)Reported Device Performance (Modified Device)
Detection LimitsComparable to predicate device (Analytical Sensitivity: 0.20 µg/dL (5.5 nmol/L) for predicate)LoB: 0.014 µg/dL (0.39 nmol/L) LoD: 0.07 µg/dL (1.9 nmol/L) LoQ: 0.25 µg/dL (6.9 nmol/L)
LinearityConsistency with predicate device (information as per K931409)Shown to be linear from 0.19 - 54.7 µg/dL (reportable range 1-50 µg/dL). Information as per K931409 for IFU.
Repeatability/PrecisionConsistency with predicate device (information as per K931409)Information provided in the Instruction for Use has not changed and are as per K931409.
Spike RecoveryConsistency with predicate device (information as per K931409)Information provided in the Instruction for Use has not changed and are as per K931409.
Method ComparisonStrong correlation to predicate deviceRegression equation: IMM 2000 = 0.996 (IMMULITE 2000 commercial) - 0.0766 µg/dL. r = 0.981
Specificity (Cross-Reactivity)Minimal cross-reactivity with listed compounds, comparable to predicate and newly evaluated compounds.Detailed table provided for % Cross-Reactivity for many compounds (e.g., Corticosterone: 0.90%, Prednisolone: 23.80%).
InterferenceMinimal interference from common substances (bilirubin, hemoglobin, intralipid, biotin), comparable to predicate.Biotin: Observed Mean % Recovery = 108%. Bilirubin, Hemolysis, Lipemia: information as per K931409 for IFU.

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

  • Method Comparison:

    • Sample Size: 149 native patient samples.
    • Data Provenance: Not explicitly stated, but "native patient samples" implies clinical samples, likely from a hospital or lab. Retrospective or prospective is not specified. Country of origin not specified.
  • Linearity:

    • Sample Size: Not explicitly stated as a number of unique patient samples, but 9 levels of dilutions were prepared from high and low human serum pools.
    • Data Provenance: Human serum pools. Retrospective or prospective, and country of origin are not specified.
  • Specificity (Cross-Reactivity):

    • Sample Size: Not explicitly stated, but multiple cross-reactant solutions were prepared and spiked into "a blank sample (charcoal-adsorbed human serum)."
    • Data Provenance: Charcoal-adsorbed human serum.
  • Interference:

    • Sample Size: 5 patient samples.
    • Data Provenance: Not explicitly stated, but "patient samples" implies clinical samples. Retrospective or prospective, and country of origin are not specified.

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

This information is not provided in the document. For in vitro diagnostic assays measuring specific analytes, the "ground truth" is typically the measured value itself, often established by a validated reference method or the predicate device, rather than expert interpretation of images or clinical findings.


4. Adjudication Method for the Test Set:

This is not applicable in the context of an in vitro diagnostic assay like this. Adjudication methods (e.g., 2+1, 3+1) are common in studies involving subjective assessments, such as imaging interpretation by multiple readers. For quantitative measurements, the "truth" is typically derived from the measurement itself.


5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, and the effect size of how much human readers improve with AI vs without AI assistance:

This is not applicable. The device is an in vitro diagnostic assay, not an AI or imaging device that assists human readers.


6. If a Standalone (i.e. algorithm only without human-in-the loop performance) was done:

This is not applicable. The device is a laboratory instrument (IMMULITE® 2000 System Analyzers) that performs a chemiluminescent immunoassay. It does not involve a "standalone algorithm" in the same sense as an AI diagnostic software. Its performance is inherent to the assay and instrument.


7. The Type of Ground Truth Used:

For this type of in vitro diagnostic device, the "ground truth" is established by:

  • Reference Methods/Predicate Device: For method comparison, the "truth" is implicitly the values obtained from the predicate device (unmodified IMMULITE® 2000 Cortisol assay).
  • Known Concentrations: For linearity, detection limits, specificity, and interference studies, the "ground truth" is based on precisely prepared samples with known concentrations of cortisol, cross-reactants, or interferents, or "spiked" samples where the added amount is known. These are often prepared from certified reference materials or highly pure substances.

8. The Sample Size for the Training Set:

This is not applicable. This is an immunoassay device, not a machine learning or AI model that requires a "training set" in the conventional sense. The development and optimization of the assay chemistry, reagents, and instrument operation are based on laboratory experiments and validation processes, not data training.


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

This is not applicable as there is no "training set" for this type of device. The accuracy of the assay is established through extensive analytical validation using prepared controls, reference materials, and patient samples compared against established methods.

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Image /page/0/Picture/0 description: The image contains the logo of the U.S. Food and Drug Administration (FDA). On the left is the Department of Health & Human Services logo. To the right of that is the FDA logo, with the letters "FDA" in a blue box, followed by the words "U.S. FOOD & DRUG" in blue, and then the word "ADMINISTRATION" in a smaller font size below that.

January 15, 2021

Siemens Healthcare Diagnostics Products Ltd. Malgorzata Robak Regulatory Affairs Supervisor Glyn Rhonwy. Llanberis Caernarfon, Gwynedd LL55 4EL UK

Re: K202826

Trade/Device Name: IMMULITE® 2000 Cortisol Regulation Number: 21 CFR 862.1205 Regulation Name: Cortisol (Hydrocortisone And Hydroxycorticosterone) Test System Regulatory Class: Class II Product Code: CGR Dated: September 22, 2020 Received: September 24, 2020

Dear Malgorzata Robak:

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 statutes and regulations administered by other Federal agencies. You must comply with all the Act's

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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 (OS) 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 mediation-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,

Kellie B. Kelm, Ph.D. Director Division of Chemistry and Toxicology Devices OHT7: Office of In Vitro Diagnostics and Radiological Health 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) K202826

Device Name IMMULITE® 2000 Cortisol

Indications for Use (Describe)

For in vitro diagnostic use with the IMMULITE® 2000 Systems Analyzers - for the quantitative measurement of cortisol (hydrocortisone, Compound F) in serum, as an aid in the clinical assessment of adrenal status.

Type of Use (Select one or both, as applicable)
-------------------------------------------------

X Prescription Use (Part 21 CFR 801 Subpart D)

| Over-The-Counter Use (21 CFR 801 Subpart C)

CONTINUE ON A SEPARATE PAGE IF NEEDED.

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510(k) Summary of Safety and Effectiveness for IMMULITE® 2000 Cortisol

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

  • A. 510(k) Number:_k202826
  • B. Purpose of the Submission Modified Device - new supplier of the antibody
  • C. Applicant:
Contact:Malgorzata Robak
Regulatory Affairs Supervisor
Address:Siemens Healthcare Diagnostics Products Limited
Glyn Rhonwy
Llanberis, Caernarfon
LL55 4EL
United Kingdom
Phone:+44 7921 882559
E-mail:malgorzata.robak@siemens-healthineers.com
Date:January 8, 2021

D. Proprietary and Established Name:

IMMULITE® 2000 Cortisol

E. Measurand

Cortisol

F. Regulatory Information

Trade Name:IMMULITE® 2000 Cortisol
Common Name:Chemiluminescence Immunoassay, for thedetermination of Cortisol
Classification Name:Cortisol Test System
FDA Classification:Class II
Review Panel:Clinical Chemistry
Product Code:CRG
Requlation Number:21 CFR 862.1205

G. Predicate Device:

Device Name: IMMULITE® 2000 Cortisol

510(k) Number: K931409

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Healthine

H. Intended Use:

Same as Indication for Use

-Indications for Use:

For in vitro diagnostic use with the IMMULITE® 2000 Systems Analyzers — for the quantitative measurement of cortisol (hydrocortisone, Compound F) in serum, as an aid in the clinical assessment of adrenal status.

J. Special Conditions for Use statement(s):

For Prescription Use Only

K. Special Instrument Requirements

For use with IMMULITE® 2000

L. Device Description

The IMMULITE 2000 Cortisol assay is comprised of the following components:

ComponentVolumeIngredients
Cortisol Bead Pack(solid phase)200 beadsPolyclonal rabbit anti-cortisol antibody.
Cortisol ReagentWedge (liquidphase)11.5 mLAlkaline phosphatase (bovine calfintestine) conjugated to cortisol in buffer,with preservative.
Cortisol Adjustors(Low and High)3 mLCortisol in processed human serum, withpreservative.

M. Substantial Equivalence Information

The following table demonstrates substantial equivalence between the IMMULITE 2000 Cortisol (Candidate Device) with an antibody from a new supplier and the currently marketed IMMULITE 2000 (Predicate Device) that was cleared under 510 (k) K931409.

Trade nameCandidate Device (Modified)IMMULITE® 2000 CortisolPredicate device(Unmodified)IMMULITE® 2000 Cortisol
Intended UseFor in vitro diagnostic usewith the IMMULITE® 2000Systems Analyzers — forthe quantitativemeasurement of cortisol(hydrocortisone, CompoundF) in serum, as an aid in theclinical assessment ofadrenal status.For in vitro diagnostic usewith the IMMULITE® 2000Systems Analyzers — forthe quantitativemeasurement of cortisol(hydrocortisone, CompoundF) in serum, as an aid in theclinical assessment ofadrenal status.
AnalyteCortisolSame
AutomatedAutomated AssaySame

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Trade nameCandidate Device (Modified)Predicate device(Unmodified)
IMMULITE® 2000 CortisolIMMULITE® 2000 Cortisol
MeasurementQuantitativeSame
Sample TypeHuman serumSame
DetectionLimitLoB: 0.014 µg/dL(0.39 nmol/L)Analytical Sensitivity: 0.20 µg/dL (5.5 nmol/L)
LoD: 0.07 µg/dL(1.9 nmol/L)Not Applicable
LoQ: 0.25 µg/dL(6.9 nmol/L)Not Applicable
CalibrationRange1-50 µg/dL (28 to 1380 nmol/L)Same
OperatingPrincipleCompetitiveSame
TechnologyChemiluminescent enzymeimmunoassaySame
InstrumentIMMULITE 2000Same
SampleVolume10 µL10 µL
CalibratorTwo levels (low & high)cortisol adjustorSame
ControlsCommercialCommercial
DetectionEnzymeconjugateAlkaline phosphatase(bovine calf intestine)conjugated to cortisolSame
CaptureAntibodyPolyclonal rabbit anti-cortisolSame

N. Test Principle

IMMULITE 2000 Cortisol is a solid-phase, enzyme-labeled chemiluminescent competitive immunoassay. The solid phase (bead) is coated with polyclonal rabbit anti-cortisol antibody. The liquid phase consists of alkaline phosphatase (bovine calf intestine) conjugated to cortisol. The patient sample and the reagent are incubated together with the coated bead for 30 minutes. During this time, cortisol in the sample competes with enzyme-conjugated cortisol in the reagent for a limited number of antibody binding sites on the bead. Unbound patient sample and enzyme conjugate are then removed by centrifugal washes. Finally, chemiluminescent substrate is added to the test unit containing the bead and the signal is generated inversely proportional to the bound enzyme.

O. Performance Characteristics

The assay principle, design and reagent formulation has not changed from the original device. Substantial equivalence was demonstrated by testing several

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Healthineer

performance characteristics including detection limits, linearity, precision, spike recovery, method comparison, interfering and cross-reactive substances. All the studies evaluated produced acceptable results when compared to the Predicate device and were deemed verified.

1. Detection Limits

LoB, LoD, and LoQ were determined in accordance with Clinical and Laboratory Standards Institute (CLSI) Section 008, p. 17-A2. The LoB/LoD/LoQ estimates are summarized below:

Limit of Blank (LoB)0.014 µg/dL (0.39 nmol/L)
Limit of Detection (LoD)0.07 µg/dL (1.9 nmol/L)
Limit of Quantitation (LoQ)0.25 µg/dL (6.9nmol/L)

The reportable range of the IMMULITE 2000 Cortisol assay is 1 to 50 µg/dL (28 to 1380 nmol/L).

2. Linearity

The Linearity study was conducted in accordance with the principles described in CLSI EP06-A: Evaluation of the Linearity of Quantitative Measurement Procedures: A Statistical Approach; Approved Guideline. Samples spanning the assay range were prepared by combining a high human serum pool with a low human serum pool for a total of 9 levels of dilutions prepared by mixing the high and low serum pools. The high serum pool consisted of a human serum pool sample spiked with cortisol to obtain a desired cortisol concentration at the upper end of the working range of the assay (observed concentration: 54.7ug/dL). The low serum pool consisted of a low-level human serum pool diluted with charcoal-adsorbed human serum in order to achieve a cortisol concentration at the approximate LoQ (observed concentration: 0.2 µg/dL).The modified IMMULITE 2000 Cortisol assay has been shown to be linear from 0.19 - 54.7 µg/dL. The Linearity information provided in the Instruction for Use for modified IMMULITE 2000 Cortisol has not changed and are as per K931409.

3. Repeatability and Within-Lab Precision

The repeatability and within-lab precision information provided in the Instruction for Use for modified IMMULITE 2000 Cortisol has not changed and are as per K931409.

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4. Spike Recovery

The spike and recovery information provided in the Instruction for Use for modified IMMULITE 2000 Cortisol has not changed and are as per K931409.

5. Method Comparison with predicate device

A method comparison study was performed by comparing the modified device to the currently-marketed predicate device (unmodified IMMULITE 2000 Cortisol Assay) in accordance with CLSI EP09c Measurement Procedure Comparison and Bias Estimation Using Patient Samples, 3rd Edition. A total of 149 native patient samples covering the full range of the assay were assayed in duplicate split across 4 runs, with each run on a different instrument (40 patients on instrument 1-3, and 30 patients on instrument 4).

SampleCategoryNRangeRegression equation
Serum1491.97 – 48.7µg/dLIMM 2000 = 0.996 (IMMULITE 2000 commercial) -0.0766 µg/dL. r = 0.981

6. Specificity (Cross-Reactivity)

Specificity (cross-reactivity) of the modified IMMULITE 2000 Cortisol assay to the various compounds listed in the Table below were evaluated. Crossreactant solutions were prepared by dissolving each cross-reactant into an appropriate solvent (ethanol, methanol or NaOH). Each cross-reactant was then spiked at a ratio of 1:19 into an aliquot of a blank sample (charcoalabsorbed human serum) such that the final concentration in the sample was equal to that outlined in Table below. Blank samples were also prepared which consisted of charcoal-adsorbed human serum spiked 1:19 with the solvents used to prepare the cross-reactants. In addition to the cross reactants evaluated in K931409 following cross reactants were evaluated: Allotetrahydrocortisol, α-Cortol, α-Cortolone, β-Cortol' β-Cortolone, Dehydrocorticosterone 20a-Dihydrocortisol, 20ß-Dihydrocortisol, 20a-Dihydrocortisone, Estradiol, Fludrocortisone. Complete summary of the results are summarized below.

CompoundCross-Reactantaddedconcentration(ug/dL)% Cross-Reactivity
Aldosterone1000ND
Androstenedione10000ND
Betamethasone1000ND
Corticosterone4000.90%
Cortisone4001.60%
11-Deoxycorticosterone400ND
CompoundCross-Reactantaddedconcentration(µg/dL)% Cross-Reactivity
11-Deoxycortisol1004.70%
21-Deoxycortisone500ND
Dexamethasone500ND
DHEA-SO410000ND
Estriol100ND
Estrone500ND
Fluticasone22ND
17α-Hydroxyprogesterone400ND
Methotrexate100ND
Methylprednisolone2001.00%
Prednisolone823.80%
Prednisone16ND
Pregnanediol2000ND
Progesterone400ND
Spironolactone1000ND
Tetrahydrocortisone400ND
Triamcinolone5000ND
Allotetrahydrocortisol1002.41%
α-Cortolone1000ND
α-Cortol1000ND
β-Cortol1000ND
β-Cortolone1000ND
11-Dehydrocorticosterone1000ND
20α-dihydrocortisol10000.368%
20β-dihydrocortisol1000ND
20α-dihydrocortisone1000ND
Fludrocortisone1000ND
Estradiol1000ND

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7. Interference

Interference with the modified IMMULITE 2000 Cortisol assay was determined for the following substances: conjugated and unconjugated bilirubin, hemoglobin, intralipid and biotin. The paired difference approach was employed for this study as per CLSI EP07: Interference Testing in Clinical Chemistry, 3rd Edition. Working stock solutions of the interfering substance were prepared and spiked into 5 patient samples such that the final interferent

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concentration in the sample was equal to that found in Table below. The 5 patient samples ranged from 3.6 – 22.1 µg/dL. The interference information for Bilirubin, Hemolysis and Lipemia provided in the Instruction for Use for modified IMMULITE 2000 Cortisol has not changed and are as per K931409. Information regarding Biotin interference are summarized below:

InterferingSubstanceInterferingsubstancespikingconcentrationObservedMean %Recovery
Biotin3500ng/mL108%

8. Clinical Evaluation

Not applicable

P. Conclusion

Based on the results of comparative testing, the modified IMMULITE® 2000 Cortisol is substantially equivalent to the currently marketed predicate device, IMMULITE® 2000 Cortisol.

§ 862.1205 Cortisol (hydrocortisone and hydroxycorticosterone) test system.

(a)
Identification. A cortisol (hydrocortisone and hydroxycorticosterone) test system is a device intended to measure the cortisol hormones secreted by the adrenal gland in plasma and urine. Measurements of cortisol are used in the diagnosis and treatment of disorders of the adrenal gland.(b)
Classification. Class II.