Binding assay for the in vitro quantitative determination of total 25-hydroxyvitamin D in human serum and plasma. This assay is to be used as an aid in the assessment of vitamin D sufficiency in adults.

The electrochemiluminescence binding assay is intended for use on cobas e immunoassay analyzers.

Device Description

Elecsys Vitamin D total III is a binding assay for the in vitro quantitative determination of total 25-hydroxyvitamin D in human serum and plasma. The assay is to be used as an aid in the assessment of vitamin D sufficiency in adults. The assay is intended for use on the cobas e immunassay analyzers. The cobas e family of analyzers employ the electrochemiluminescence "ECLIA" technology.

Elecsys Vitamin D total III utilizes a competition test principle and has a total test duration of 27 minutes:

1st incubation: By incubating the sample (15 µL ) with pretreatment reagent 1 and 2, bound 25-hydroxyvitamin D is released from the vitamin D binding protein (VDBP).
2nd incubation: By incubating the pretreated sample with the ruthenium labeled VDBP, a complex between the 25-hydroxyvitamin D and the ruthenylated VDBP is formed. A specific unlabeled antibody binds to 24,25-dihydroxyvitamin D present in the sample and inhibits cross-reactivity to this vitamin D metabolite.
3rd incubation: After addition of streptavidin-coated microparticles and 25-hydroxyvitamin D labeled with biotin, unbound ruthenylated labeled VDBP become occupied. A complex consisting of the ruthenylated VDBP and the biotinylated 25-hydroxyvitamin D is formed and becomes bound to the solid phase via interaction of biotin and streptavidin.
The reaction mixture is aspirated into the measuring cell where the microparticles are magnetically captured onto the surface of the electrode. Unbound substances are then removed with ProCell/ProCell M. Application of a voltage to the electrode then induces chemiluminescent emission which is measured by a photomultiplier.

Results are determined via a calibration curve which is instrument-specifically generated by a 2-point calibration and a master curve provided via the reagent barcode or e-barcode.

The reagent working solutions include the reagent rackpack (M, R1, R2) and the pretreatment reagents (PT1, PT2);

PT1 Pretreatment reagent 1 (white cap), 1 bottle, 4 mL: Dithiothreitol 1 g/L, pH 5.5
PT2 Pretreatment reagent 2 (gray cap), 1 bottle, 4 mL: Sodium hydroxide 57.5 g/L
M Streptavidin-coated microparticles (transparent cap), 1 bottle, 6.5 mL: Streptavidin-coated microparticles 0.72 mg/ml; preservative
R1 Vitamin D binding protein-Ru/(bpy) (gray cap), 1 bottle, 9 mL: Ruthenium labeled vitamin D binding protein 150 µg/L; bis-tris propane buffer 200 mmol/L; albumin (human) 25 g/L; pH 7.5; preservative
R2 25-hydroxyvitamin Dbiotin (black cap), 1 bottle, 8 5 mL: Biotinylated 25-hydroxyvitamin D 20 µg/L; bis-tris propane buffer 200 mmol/L; pH 8.6; preservative

AI/ML Overview

This document describes the Elecsys Vitamin D total III assay, a binding assay for the in vitro quantitative determination of total 25-hydroxyvitamin D in human serum and plasma. It is intended to aid in the assessment of vitamin D sufficiency in adults and is designed for use on cobas e immunoassay analyzers.

1. Acceptance Criteria and Reported Device Performance

The provided text details several performance characteristics and the testing conducted to meet acceptance criteria. While explicit "acceptance criteria" values are not listed in a separate table for all tests, the document states that "All predefined acceptance criteria was met" for various studies. The reported performance for each study is summarized below:

Study/Performance Characteristic	Acceptance Criteria (Implied by Met/Not Met)	Reported Device Performance
Precision	Predefined acceptance criteria for repeatability and intermediate precision	All predefined acceptance criteria met.
Lot-to-Lot Reproducibility	Predefined acceptance criteria	All predefined acceptance criteria met using three reagent lots.
Limit of Blank (LoB)	Not explicitly stated; based on CLSI EP17-A2 guidelines.	LoB claim: 2.0 ng/mL
Limit of Detection (LoD)	Not explicitly stated; based on CLSI EP17-A2 guidelines.	LoD claim: 3.0 ng/mL
Limit of Quantitation (LoQ)	Not explicitly stated; based on CLSI EP17-A2 guidelines.	LoQ claim: 6.0 ng/mL
Linearity	Confirmation within a specified range	Confirmed in the range of 2.04 - 129 ng/mL. Measuring range claim: 6.00 - 120 ng/mL.
High-Dose Hook Effect (HDHE)	No hook effect up to a certain concentration	No hook effect seen up to 10,000 ng/mL for both samples tested.
HAMA Interference	No HAMA interference observed	No HAMA interference observed.
Endogenous Interference	Predefined acceptance criteria	All predefined acceptance criteria met for 10 endogenous substances.
Cross-Reactivity	Evaluation of percent cross-reactivity with vitamin D metabolites.	- 25-hydroxyvitamin D3 (50 ng/mL): 100%- 25-hydroxyvitamin D2 (50 ng/mL): 103.3%- 24,25-dihydroxyvitamin D3 (100 ng/mL): 8.1%- 3-epi-25-hydroxyvitamin D3 (50 ng/mL): 121.6%- 3-epi-25-hydroxyvitamin D2 (50 ng/mL): 102.7%- 1,25-dihydroxyvitamin D3 (100 ng/mL): not determined- 1,25-dihydroxyvitamin D2 (100 ng/mL): 0.9%- Vitamin D3 (1000 ng/mL): 0.9%- Vitamin D2 (1000 ng/mL): 0.7%
Exogenous Interference	Predefined acceptance criteria	All predefined acceptance criteria met for 20 pharmaceutical compounds; no interference observed.
Method Comparison (LC-MS/MS)	Not explicitly stated; assessed by Deming and Passing Bablok regression.	Deming: y = 0.981x + 0.795, r = 0.982Passing Bablok: y = 0.979x + 0.675, T = 0.908
Method Comparison (Predicate Device)	Not explicitly stated; assessed by Passing Bablok regression.	Passing Bablok: y = 0.896x + 2.63, T = 0.913
Anticoagulant Effects	Predefined acceptance criteria for various sample types.	All predefined acceptance criteria met. Serum, SST, Li-Heparin, K2-EDTA, K3-EDTA plasma primary tubes are acceptable.
Plasma Separation Tubes (PSTs) Effects	Predefined acceptance criteria for PSTs from various manufacturers.	All predefined acceptance criteria met. PSTs are an acceptable sample type.
Reagent Stability (After First Opening)	Up to a specified duration	Up to 8 weeks (56 days) when stored at 2-8°C.
On-board Reagent Stability	Up to a specified duration	Up to 28 days (4 weeks) with a recommended new calibration every 7 days.
Lot Calibration Frequency	Up to a specified duration	Recommended every 12 weeks (3 months).
On-board Calibration Frequency	Up to a specified duration	Up to 7 days without a new calibration.
Reference Range Study	Determination of a 95% reference range	Calculated 95% reference range: 10.2 – 49.4 ng/mL (25.4 – 123 nmol/L).

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

Precision Measurements: Sample size not specified, but conducted with multiple measurements over 21 days according to CLSI guideline EP05-A3. Data provenance is implied to be internal testing by Roche Diagnostics.
Lot-to-Lot Reproducibility: Sample size not specified, but performed using three reagent lots. Data provenance is implied to be internal testing by Roche Diagnostics.
Limit of Blank (LoB), Limit of Detection (LoD), Limit of Quantitation (LoQ): Sample size not specified; determined according to CLSI EP17-A2. Data provenance is implied to be internal testing by Roche Diagnostics.
Linearity: Sample size not specified, but evaluated on one cobas e 601 analyzer. Data provenance is implied to be internal testing by Roche Diagnostics.
High-Dose Hook Effect (HDHE): Two-fold determination with two samples on one cobas e 601 analyzer. Data provenance is implied to be internal testing by Roche Diagnostics.
HAMA Interference: Sample size not specified, assessed on one cobas e 601 analyzer. Data provenance is implied to be internal testing by Roche Diagnostics.
Endogenous Interference: 10 endogenous substances evaluated. Sample size not specified for each substance. Data provenance is implied to be internal testing by Roche Diagnostics.
Cross-Reactivity: Cross-reactivity with various vitamin D metabolites and related compounds. Sample size not specified for each compound. Data provenance is implied to be internal testing by Roche Diagnostics.
Exogenous Interference: 17 commonly and 3 specially used pharmaceutical compounds evaluated. Sample size not specified for each compound. Data provenance is implied to be internal testing by Roche Diagnostics.
Method Comparison (LC-MS/MS): 157 single donor serum samples. Data provenance: CDC Verification Samples provided by the Vitamin D Standardization and Certification Program, with assigned values by the candidate Reference Method Procedure: ID-LCMS/MS at the CDC Vitamin D Reference Laboratory. This indicates a prospective and externally validated dataset.
Method Comparison (Predicate Device): 151 human serum samples. Data provenance is implied to be internal testing by Roche Diagnostics, comparing with their own predicate device (Elecsys Vitamin D total II).
Anticoagulant Effects: Single-donor samples (number not specified) drawn into serum, SST, Li-Heparin, K2-EDTA plasma primary tubes. Data provenance is implied to be internal testing by Roche Diagnostics.
Plasma Separation Tubes (PSTs) Effects: Single-donor samples (number not specified) drawn into PSTs from 3 separate manufacturers. Data provenance is implied to be internal testing by Roche Diagnostics.
Reagent Stability: Tested on one cobas e 601 analyzer. Data provenance is implied to be internal testing by Roche Diagnostics.
On-board Reagent Stability: Tested on one cobas e 601 analyzer. Data provenance is implied to be internal testing by Roche Diagnostics.
Lot Calibration Frequency: Tested on one cobas e 601 analyzer. Data provenance is implied to be internal testing by Roche Diagnostics.
On-board Calibration Frequency: Tested on one cobas e 601 analyzer. Data provenance is implied to be internal testing by Roche Diagnostics.
Reference Range Study: A total of 827 subjects enrolled; 463 eligible subjects included in the final determination after exclusions. Data provenance: Serum samples collected from adult subjects during summer and winter months from three geographically diverse locations in the U.S. (Northern regions). One clinical laboratory was contracted to measure samples. This indicates prospective, multi-site clinical data.

Note: For internal testing studies (precision, linearity, interference, stability), the data provenance is implied to be prospective testing conducted by Roche Diagnostics in a controlled laboratory setting.

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

The document does not describe the use of "experts" to establish ground truth in the traditional sense of medical image analysis or diagnostic interpretation by physicians.

For the Method Comparison (LC-MS/MS), the "ground truth" (or reference values) for the 157 samples was established by the CDC Verification Samples with assigned values by the candidate Reference Method Procedure: ID-LCMS/MS at the CDC Vitamin D Reference Laboratory. This implies a highly standardized and validated reference method for quantifying vitamin D, rather than expert clinical judgment.

For the Reference Range Study, "characterization testing" was used to determine whether samples met stated inclusion/exclusion criteria. This involved a variety of characterization assays on cobas e 601 or cobas c 501 analyzers, not human expert adjudication.

4. Adjudication Method

Not applicable, as the studies described primarily involve analytical performance testing using quantitative measurements against reference methods or predefined criteria, rather than qualitative assessments requiring human adjudication.

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

Not applicable. The Elecsys Vitamin D total III is an in vitro diagnostic assay, not an AI-powered image analysis or diagnostic tool that assists human readers. Therefore, an MRMC study and the concept of "human readers improve with AI vs without AI assistance" are not relevant to this device's evaluation.

6. Standalone Performance Study

Yes, a standalone study of the algorithm (in this case, the assay system's performance) was done. All the non-clinical and clinical tests described, such as precision, accuracy (method comparison), linearity, limits of detection, interference, and stability, demonstrate the standalone performance of the Elecsys Vitamin D total III assay system. The device performs the quantitative analysis without human intervention in the measurement process itself, once the sample is loaded and the assay initiated.

7. Type of Ground Truth Used

The primary ground truth used for performance evaluation, particularly for accuracy, was:

Reference Method/Standard: For the method comparison study, the CDC Verification Samples with values assigned by the ID-LCMS/MS (Isotope Dilution Liquid Chromatography-Mass Spectrometry/Mass Spectrometry) at the CDC Vitamin D Reference Laboratory served as the reference method or "ground truth" for 25-hydroxyvitamin D concentration. This is a highly accurate and precise analytical method.
Predicate Device Comparison: The predicate device, Elecsys Vitamin D total II, also served as a reference for comparison, indicating substantial equivalence.
Analytical Standards/Controls: For other analytical performance tests (e.g., precision, linearity, limits), ground truth is established through the use of certified reference materials, calibrators, and specified spiked samples with known concentrations.

8. Sample Size for the Training Set

The document does not explicitly mention a "training set" in the context of machine learning or AI algorithm development. The Elecsys Vitamin D total III is a binding assay with a defined chemical and immunological principle, not a machine learning algorithm that is "trained" on a dataset in the conventional sense. Therefore, the concept of a training set size for an AI model is not directly applicable here.

However, the assay's development and optimization would have involved extensive testing and "training" by researchers and developers in a broader, non-AI sense to establish reagent formulations, reaction conditions, and calibration parameters before formal validation studies. This is not detailed in the provided regulatory document.

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

As explained in point 8, the concept of a "training set" for AI is not directly applicable to this device. Therefore, the method for establishing ground truth for such a set is also not discussed. The assay's fundamental performance characteristics (e.g., binding kinetics, signal generation) are based on established biochemical principles and extensive internal research and development, which would have leveraged known concentrations of 25-hydroxyvitamin D and its metabolites in control samples and reference materials.

Summary

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Image /page/0/Picture/0 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). The logo consists of two parts: a symbol on the left and the FDA name and title on the right. The symbol on the left is a stylized representation of a human figure, while the text on the right reads "FDA U.S. FOOD & DRUG ADMINISTRATION" in blue letters.

September 1, 2021

Roche Diagnostics Jamie Ferguson. Regulatory Affairs Principal 9115 Hague Road PO Box 50416 Indianapolis, IN 46250

Re: K210901

Trade/Device Name: Elecsys Vitamin D total III Regulation Number: 21 CFR 862.1825 Regulation Name: Vitamin D Test System Regulatory Class: Class II Product Code: MRG Dated: March 25, 2021 Received: March 26, 2021

Dear Jamie Ferguson:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal

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statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.

For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely,

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

Submission Number (if known)

K210901 Device Name

Elecsys Vitamin D total III

Indications for Use (Describe)

The electrochemiluminescence binding assay is intended for use on cobas e immunoassay analyzers.

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

Prescription Use (Part 21 CFR 801 Subpart D)

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

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Contact Details		21 CFR 807.92(a)(1)
Applicant Name	Roche Diagnostics
Applicant Address	9115 Hague Road, PO Box 50416, Indianapolis, IN, 46250, United States of America
Applicant Contact Telephone	317-270-7402
Applicant Contact	Mrs. Jamie Ferguson
Applicant Contact Email	jamie.ferguson@roche.com
Device Name		21 CFR 807.92(a)(2)
Device Trade Name	Elecsys Vitamin D total III (09038078160)
Common Name	Vitamin D test system
Classification Name	System, Test, Vitamin D
Regulation Number	862.1825
Product Code	MRG
Legally Marketed Predicate Devices		21 CFR 807.92(a)(3)
Predicate #	Predicate Trade Name (Primary Predicate is listed first)		Product Code
K162840	Elecsys Vitamin D total II		MRG
Device Description Summary		21 CFR 807.92(a)(4)
Elecsys Vitamin D total III is a binding assay for the in vitro quantitative determination of total 25-hydroxyvitamin D in human serum and plasma. The assay is to be used as an aid in the assessment of vitamin D sufficiency in adults. The assay is intended for use on the cobas e immunassay analyzers. The cobas e family of analyzers employ the electrochemiluminescence "ECLIA" technology.
Elecsys Vitamin D total III utilizes a competition test principle and has a total test duration of 27 minutes:
- 1st incubation: By incubating the sample (15 µL ) with pretreatment reagent 1 and 2, bound 25-hydroxyvitamin D is released from the vitamin D binding protein (VDBP).
- 2nd incubation: By incubating the pretreated sample with the ruthenium labeled VDBP, a complex between the 25-hydroxyvitamin D and the ruthenylated VDBP is formed. A specific unlabeled antibody binds to 24,25-dihydroxyvitamin D present in the sample and inhibits cross-reactivity to this vitamin D metabolite.
- 3rd incubation: After addition of streptavidin-coated microparticles and 25-hydroxyvitamin D labeled with biotin, unbound ruthenylated labeled VDBP become occupied. A complex consisting of the ruthenylated VDBP and the biotinylated 25-hydroxyvitamin D is formed and becomes bound to the solid phase via interaction of biotin and streptavidin.
- The reaction mixture is aspirated into the measuring cell where the microparticles are magnetically captured onto the surface of the electrode. Unbound substances are then removed with ProCell/ProCell M. Application of a voltage to the electrode then induces chemiluminescent emission which is measured by a photomultiplier.

Results are determined via a calibration curve which is instrument-specifically generated by a 2-point calibration and a master curve provided via the reagent barcode or e-barcode.

The reagent working solutions include the reagent rackpack (M, R1, R2) and the pretreatment reagents (PT1, PT2);

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PT1 Pretreatment reagent 1 (white cap), 1 bottle, 4 mL: Dithiothreitol 1 g/L, pH 5.5

PT2 Pretreatment reagent 2 (gray cap), 1 bottle, 4 mL: Sodium hydroxide 57.5 g/L

M Streptavidin-coated microparticles (transparent cap), 1 bottle, 6.5 mL: Streptavidin-coated microparticles 0.72 mg/ml; preservative R1 Vitamin D binding protein-Ru/(bpy) (gray cap), 1 bottle, 9 mL: Ruthenium labeled vitamin D binding protein 150 µg/L; bis-tris propane buffer 200 mmol/L; albumin (human) 25 g/L; pH 7.5; preservative

R2 25-hydroxyvitamin D~biotin (black cap), 1 bottle, 8 5 mL: Biotinylated 25-hydroxyvitamin D 20 µg/L; bis-tris propane buffer 200 mmol/L; pH 8.6; preservative

Intended Use/Indications for Use

The electrochemiluminescence binding assay is intended for use on cobas e immunoassay analyzers.

Indications for Use Comparison

Elecsys Vitamin D total III is substantially equivalent to Elecsys Vitamin D total II, cleared under K162840.

The intended use of Elecsys Vitamin D total III was updated to specify it is a binding assay and to remove analyzers that are no longer supported for use with Roche assays. The indications for use of Elecys Vitamin D total III did not change from the predicate device.

Technological Comparison

Roche Diagnostics has updated the current Elecsys Vitamin D total II assay in order to improve biotin tolerance. A technical solution was implemented by adding an anti-biotin antibody to one of the reagents, which allows depletion of biotin in a patient sample by binding free biotin. Roche also increased robustness for pre-analytical sample qualities by optimizing the ratio of chemical components. In addition, the measuring range was expanded to meet customer needs. No other technological characteristics were changed. The submitted information in this premarket notification supports a substantial equivalence decision.

Non-Clinical and/or Clinical Tests Summary & Conclusions 21 CFR 807.92(b)

Precision measurements were conducted for both 21 days with the Elecsys Vitamin D total III assay to evaluate repeatability (within-run precision) and internediate precision) according the CLSI quideline EP05-A3. All preceined acceptance criteria was met for the precision experiments.

Lot-to-lot reproducibility was performed for the Elecsys Vitamin D total III assay using three reagent lots. All predefined acceptance criteria was met for the lot-to-lot reproducibility experiment.

The Limit of Blank (LoB) was determined according to CLSI EP17-A2. The LoB claim in the labeling will be set to 2.0 ng/mL.

The Limit of Detection (LoD) was determined according to CLSI EP17-A2. The LoD claim in the labeling will be set to 3.0 ng/mL.

The Limit of Quantitation (LoQ) was determined according to CLSI EP17-A2. The LoQ claim in the labeling will be set to 6.0 ng/mL.

Linearity was evaluated according to CLSI EP06-A with the Elecsys Vitamin D total III assay on one cobas e 601 analyzer. Linearity was confirmed in the range of 2.04 - 129 ng/ml, and a measuring range of 6.00 - 120 ng/ml will be claimed in the labeling.

The high-dose hook effect (HDHE) of the Elecsys Vitamin D total III assay was assessed on one cobas e 601 analyzer in two-fold determination. No hook effect was seen up to 10,000 ng/mL for both samples.

The effect of the presence of human anti-mouse antibodies (HAMA) on the Elecsys Vitamin D total III assay was assessed on one cobas e 601 analyzer. No HAMA interference was observed.

Ten endogenous substances were evaluated for potential interference with the Elecsys Vitamin D total III assay on the cobas e 601 analyzer. All predefined acceptance citeria was met, and the proposed labeling claims for each endogenous substance can be found below:

Biotin ≤ 600 ng/mL Lipemia (Intralipid) ≤ 300 mg/dL

21 CFR 807.92(a)(5)

21 CFR 807.92(a)(6)

21 CFR 807.92(a)(5)

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Hemoglobin ≤ 600 mg/dL Bilirubin ≤ 66 mg/dL Rheumatoid Factor ≤ 1200 IU/mL Serum Albumin ≤ 7 g/dL lgG ≤ 7 g/dL IgA ≤ 1.3 g/dL lgM ≤ 1 g/dL Triglyceride ≤ 300 mg/dL

A cross-reactivity study was conducted with Elecsys Vitamin D total III on the cobas e 601 analyzer to evaluate the posreactivity of the assay with other vitamin D metabolites that occur in the human body during and catabolism. The percent cross-reactivity was calculated and normalized to the cross-reactivity of 25-hydroxyvitamin D3. The mean results are summarized below:

Cross-reactant / Mean cross-reactivity (%) 25-hydroxyvitamin D3 (50 ng/mL) / 100 25-hydroxyvitamin D2 (50 ng/mL) / 103.3 24,25-dihydroxyvitamin D3 (100 ng/mL) / 8.1 3-epi-25-hydroxyvitamin D3 (50 ng/mL) / 121.6 3-epi-25-hydroxyvitamin D2 (50 ng/mL) / 102.7 1,25-dihydroxyvitamin D3 (100 ng/mL) / not determined 1,25-dihydroxyvitamin D2 (100 ng/mL) / 0.9 Vitamin D3 (1000 ng/mL) / 0.9 Vitamin D2 (1000 ng/mL) / 0.7

An exogenous interference study was conducted to evaluate 17 commonly and three specially used pharmaceutical compounds for potential interference with the Elecsys Vitamin D total III assay on the cobas e 601 analyzer. The predefined acceptance criteria was met for all drugs tested, and no interference was observed.

A method comparison was performed with the LC-MS/MS reference method and the Elecsys Vitamin D total of 157 single donor serum samples (CDC Verification Samples provided by the Vitamin D Standardization and Certification Program with assigned values by the candidate Reference Method Procedure: ID-LCMS/MS at the CDC Vitamin D Reference Laborabory). The sample concentrations were between 5.64 ng/mL (14.1 nmol/L) and 118 ng/mL (295 nmol/L). The results can be found below:

Deming y = 0.981x + 0.795 r = 0.982 Passing Bablok y = 0.979x + 0.675 T = 0.908

A method comparison was performed with the predicate device, Elecsys Vitamin D total III, and the Elecsys Vitamin D total III assay, using a total of 151 human serum samples. The results can be found below:

Passing Bablok y = 0.896x + 2.63 T = 0.913

The effect on quantitation of analyte in the presence of anticoaqulants with Elecsys Vitamin D total III was determined by comparing values obtained from single-donor samples drawn into serum, Serum Separation Tubes (SST), and Li-Heparin, K2-EDTA plasma primary tubes. All predefined acceptance criteria was met, supporting the labeling claim that serum, SSTs, and Li-Heparin, K2-EDTA and K3-EDTA plasma primary tubes are acceptable sample types.

The effect on quantitation of analyte with the use of plasma separation tubes (PSTs) with Elecsys Vitamin D total III was determined by comparing values obtained from singles drawn into PSTs from 3 separate manufacturers. The predefined acceptance criteria was met, supporting the labeling claim PSTs are an acceptable sample type.

Reagent stability after first opening for the Elecsys Vitamin D total III assay was tested on one cobas e 601 analyzer. Elecsys Vitamin D total III reagent kits can be used after first opening for up to 8 weeks (56 days) when stored at 2-8℃.

On-board reagent stability for the Elecsys Vitamin D total III assay was tested on one cobas e 601 analyzer. Elecsys Vitamin D total III reagent kits can be stored on-board the analyzers for up to 28 days (4 weeks). A new calibration of the kit kept on-board is recommended every 7 days.

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Lot calibration frequency for the Elecsys Vitamin D total III assay was tested on one cobas e 601 analyzer. Calibrations of an Elecsys Vitamin D total III reagent lot is recommended every 12 weeks (3 months). During that time period, fresh reagent kits of the same lot can be used without calibration using the calibration curve of the day 0 reagent kit.

Reagent on-board calibration frequency for Elecsys Vitamin D total III assay was tested on one cobas e 601 analyzer. Elecsys Vitamin D total III reagent kits can be stored on board of the analyzers for up to 7 days without a new calibration.

A Reference Range study for the Elecsys Vitamin D total III assay on the cobas e 601 analyzer was performed in order to determine reference range values under routine laboratory conditions. Serum samples were collected from adult subjects during summer and winter months from three geographically diverse locations in the U.S. (Northern recions). One clinical laboratory was contracted to measure samples with Elecsys Vitamin D total III on the cobas e 601 analyzer and a variety of characterization assays on either the cobas e 601 or cobas c 501 analyzer. Characterization testing was used to determine whether the sample met the stated inclusion/exclusion criteria. Subjects that were not within the respective reference ranges of any of the eight characterization testing assays were not included in the final Elecsys Vitamin D total III reference range determination.

A total of 827 subjects were enrolled and had characterization testing preformed. Of the 827 subjects enrolled and tested, 361 were excluded as they did not pass all eight characterization tests and two were excluded after testing was complete due to concomitant medication use. One subject did not have serum available for vitamin D testing. A total of 463 eligible subjects were included in the final Elecsys Vitamin D total III reference range determination.

The calculated 95% reference range for the total enrolled population of Elecsys Vitamin D total III is 10.2 – 49.4 ng/mL (25.4 – 123 nmol/ L).

The information provided in this 510(k) Premarket Notification support the determination that Elecsys Vitamin D total III is substantially equivalent to the predicate device, Elecsys Vitamin D total II.

Regulation Number and Section

§ 862.1825 Vitamin D test system.

(a)
Identification. A vitamin D test system is a device intended for use in clinical laboratories for the quantitative determination of 25-hydroxyvitamin D (25-OH-D) and other hydroxylated metabolites of vitamin D in serum or plasma to be used in the assessment of vitamin D sufficiency.(b)
Classification. Class II (special controls). Vitamin D test systems must comply with the following special controls:(1) Labeling in conformance with 21 CFR 809.10 and
(2) Compliance with existing standards of the National Committee on Clinical Laboratory Standards.