The Dimension Tacrolimus Flex® Reagent Cartridge (TAC) is an in vitro diagnostic test for the quantitative measurement of tacrolimus in human whole blood on the Dimension® clinical chemistry system. Measurements of tacrolimus are used as an aid in the management of tacrolimus therapy in renal and hepatic transplant patients.

The Dimension Tacrolimus Callbrator (TAC CAL) is an in vitro diagnostic product for the Tacrolimus (TAC) method on the Dimension® clinical chemistry system.

Device Description

The automated Dimension® TAC method uses an immunoassay technique in which free and tacrolimus-bound antibody-enzyme conjugate is separated using magnetic particles. The assay is performed using a method specific Flex® reagent cartridge. The Flex® cartridge contains a pretreatment reagent, antibody-ß-galactosidase conjugate, tacrolimus immobilized on chromium dioxide particles, chlorophenol red ß-d-galactopyranoside (CPRG) substrate, and diluent to hydrate the tablets.

Dimension® Tacrolimus (TAC) Calibrator is five level frozen liquid, whole blood hemolysate containing purified tacrolimus. The provided in 4.0 mL vials, 2 vials per level. There are five calibrator levels per kit which span the assay range for the Dimension® Tacrolimus (TAC) assay. Calibrators are filled with 1.0 mL per vial except for Level 1 calibrator which contains 2.0 mL per vial.

AI/ML Overview

Here's a summary of the acceptance criteria and study information for the Dimension Tacrolimus Flex® Reagent Cartridge (TAC) and Dimension Tacrolimus Calibrator (TAC CAL), based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state acceptance criteria in a quantitative format for most categories. Instead, it describes the type of testing performed and then indicates whether the device met certain expectations (e.g., "All samples met the acceptance criterion of ≤ 10% mean bias in recovery"). Where specific quantitative performance is given, it is included.

Performance Category	Acceptance Criteria (Explicit or Implied)	Reported Device Performance
Precision	Not explicitly stated (implied to be acceptable for clinical use)	Typical precision at levels ranging from 1.8 to 27.4 ng/mL was ≤ 6.6% CV for Repeatability and ≤ 13.1% CV for Within Lab.
Linearity (Analytical Measuring Range)	Established by Limit of Quantitation (LoQ) and linearity study.	Assay range established as 1.0 - 30.0 ng/mL. Linear regression, 2nd, and 3rd order polynomial regressions performed. The specific "acceptance criterion" for linearity (e.g., R-squared value, deviation from linearity) is not explicitly stated, but the range was "established".
Specificity (Cross-reactivity to Metabolites)	Not explicitly stated (implied acceptable low cross-reactivity for relevant metabolites).	* M-I (13-O-desmethyl-tacrolimus): 1% cross-reactivity. * M-II (31-O-desmethyl-tacrolimus): 18% cross-reactivity. * M-III (15-O-desmethyl-tacrolimus): 15% cross-reactivity. * M-IV (12-O-hydroxyl-tacrolimus): 99% cross-reactivity. * M-V (15,31-O-didesmethyltacrolimus): 1% cross-reactivity. * M-VI (13,31-O-didesmethyl-tacrolimus): 1% cross-reactivity. * M-VII (13,15-O-didesmethyl-tacrolimus): 43% cross-reactivity. * M-VIII (unknown name): 0% cross-reactivity.
Specificity (Interference from Endogenous/Co-administered Drugs)	Bias less than 10% at tested levels.	Co-administered drugs and other compounds tested for interference, exhibited less than 10% bias at the levels tested.
Recovery	≤ 10% mean bias in recovery.	All samples met the acceptance criterion of ≤ 10% mean bias in recovery.
Method Comparison (vs. Reference Method LC-MS/MS)	Not explicitly stated (implied acceptable correlation and agreement for clinical use based on regression).	Slope: 1.04, Intercept: -0.30, r: 0.966 (n=315, Range: 1.3-24.9 ng/mL).
Method Comparison (vs. Predicate ARCHITECT Tacrolimus Assay)	Not explicitly stated (implied acceptable correlation and agreement for clinical use based on regression).	Slope: 0.99, Intercept: -0.42, r: 0.979 (n=308, Range: 2.1-24.2 ng/mL).
Method Comparison (vs. Predicate Dimension Tacrolimus (TACR) method)	Not explicitly stated (implied acceptable correlation and agreement for clinical use based on regression).	Slope: 1.00, Intercept: -0.50, r: 0.957 (n=213, Range: 2.6 - 21.7 ng/mL).
Calibrator Stability (Unopened)	Stable until expiration date.	Stored frozen (-25 to -15 °C) until expiration date.
Calibrator Stability (Thawed)	Stable for 30 days when recapped and stored at 2-8°C.	Assigned values are stable for 30 days when recapped immediately after use and stored at 2-8°C.

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

Precision: No specific sample size for a single "test set" is provided, but reproducibility testing was conducted using different levels (1.8 to 27.4 ng/mL).
Linearity: No specific sample size mentioned, but the study was performed by mixing a sample with a known high tacrolimus concentration (40.3 ng/mL) with a normal patient pool with no tacrolimus in various ratios.
Specificity: No specific sample size mentioned for the interference or cross-reactivity studies, beyond stating "compounds tested" and "major tacrolimus metabolite... as well as minor metabolites."
Recovery: No specific sample size mentioned, but "samples spiked with USP tacrolimus" were used.
Method Comparison:
- Versus LC-MS/MS: n = 315 patient samples.
- Versus ARCHITECT Tacrolimus Assay: n = 308 patient samples.
- Versus Dimension Tacrolimus (TACR) method: n = 213 patient samples.
Data Provenance: The document states that method comparison studies, and some precision testing, were performed at two external evaluation sites in addition to internal testing. Patient samples for method comparison included a "nearly equal distribution of liver and kidney transplant patients." The country of origin is not specified but is implied to be within the scope of Siemens Healthcare Diagnostics operations, likely in the US given the FDA submission. The studies were retrospective in the sense that existing patient samples (whole blood) were used, though the testing itself was prospective for the device evaluation.

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

The concept of "experts" for ground truth (e.g., radiologists) is not applicable here as this is an in vitro diagnostic (IVD) assay. The ground truth for the method comparison studies was established using:

LC-MS/MS reference method: This is an analytical "gold standard" for measuring tacrolimus concentrations.
Predicate devices: ARCHITECT Tacrolimus Assay (K070820) and Dimension Tacrolimus (TACR) method (K060502), which are already legally marketed and accepted methods.

The experts involved would be the laboratory personnel performing these high-complexity reference and predicate assays, who are implicitly qualified to conduct such tests according to established laboratory practices. No specific number or qualifications (e.g., "10 years of experience") are provided for these individuals.

4. Adjudication Method for the Test Set

Not applicable. This is an IVD assay where quantitative measurements are obtained. Adjudication typically refers to resolving discrepancies between multiple human readers in image-based diagnostics. Here, the "truth" is established by a reference method or comparison to established predicate devices.

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

Not applicable. This is an in vitro diagnostic (IVD) assay and does not involve human readers interpreting images, nor does it involve AI assistance in the context of imaging diagnostics. The comparison is between the new device's analytical performance and established reference/predicate methods.

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

Yes, the studies reported are essentially standalone performance evaluations of the Dimension Tacrolimus Flex® Reagent Cartridge (TAC) system. The described testing (precision, linearity, specificity, recovery, method comparison) evaluates the analytical performance of the automated assay system itself. Human intervention is limited to standard laboratory procedures like sample preparation, loading, and result interpretation, not in an "AI-assisted reader" capacity.

7. The Type of Ground Truth Used

Analytical Measuring Range (Linearity) & Recovery: "USP tacrolimus" (United States Pharmacopeia tacrolimus), which refers to highly pure, standardized tacrolimus used to spike samples to known concentrations.
Method Comparison:
- LC-MS/MS Assay for Tacrolimus: This is considered the analytical "reference method" and serves as a highly accurate ground truth.
- Predicate Devices: ARCHITECT Tacrolimus Assay and Dimension Tacrolimus (TACR) method. While not a "ground truth" in the strictest sense of an absolute standard, they serve as the established clinical "truth" for comparison, demonstrating substantial equivalence.

8. The Sample Size for the Training Set

No explicit "training set" or sample size for it is mentioned. This is a chemical assay, not a machine learning algorithm in the typical sense that requires a separate training set for model development. The development of the assay reagents and protocols would involve internal optimization, but this is not typically referred to as a "training set" in the context of regulatory submissions for IVD devices.

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

Since there is no explicit "training set" or machine learning model, this question is not directly applicable. The development and optimization of the assay would rely on:

Understanding of tacrolimus chemistry and pharmacology: To design reagents that specifically target tacrolimus.
Standards and reference materials: Such as purified tacrolimus (used for calibrators and recovery studies) to ensure accurate concentration measurements.
Internal validation and optimization studies: To fine-tune reagent concentrations, reaction conditions, and instrument parameters to achieve desired analytical performance characteristics.

Summary

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

SIEMENS HEALTHCARE DIAGNOSTICS KATHLEEN DRAY-LYONS REGULATORY AFFAIRS SPECIALIST 500 GBC DRIVE NEWARK DE 19714

November 4, 2015

Re: K150168

Trade/Device Name: Dimension Tacrolimus Flex® Reagent Cartridge (TAC) Dimension Tacrolimus Calibrator (TAC CAL) Regulation Number: 21 CFR 862.1678 Regulation Name: Tacrolimus test system Regulatory Class: II Product Code: MLM, JIT Dated: October 30, 2015 Received: November 2, 2015

Dear Ms. Dray-Lyons:

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. 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 requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Parts 801 and 809); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (OS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

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If you desire specific advice for your device on our labeling regulations (21 CFR Parts 801 and 809), please contact the Division of Industry and Consumer Education at its toll-free number (800) 638 2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm. 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

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 Industry and Consumer Education at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.

Sincerely yours,

Katherine Serrano -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

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Indications for Use

510(k) Number (if known) K150168

Device Name

Dimension Tacrolimus Flex® Reagent Cartridge (TAC) Dimension Tacrolimus Calibrator (TAC CAL)

Indications for Use (Describe)

The Dimension Tacrolimus Callbrator (TAC CAL) is an in vitro diagnostic product for the Tacrolimus (TAC) method on the Dimension® clinical chemistry system.

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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510(k) Summary

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

K150168 The assigned 510(k) number is:

1. Submitter
  Siemens Healthcare Diagnostics Inc. P.O. Box 6101 Newark, DE 19714

Tel: 302-631-9352 FAX # 302-631-6299

Contact Person: Anna Marie (Kathy) Ennis Date of Preparation: September 23, 2015

2. Device

Name of Device:	Dimension Tacrolimus Flex® reagent cartridge (TAC)
Common Name:	Tacrolimus Assay
Classification Name:	Tacrolimus Test System (21CFR§862.1678)
Regulatory Class:	II
Product Code:	MLM
Name of Device:	Dimension Tacrolimus Calibrator (TAC CAL)
Common Name:	Tacrolimus Calibrator (TAC CAL)
Classification Name:	Calibrator Secondary (21CFR§862.1150)
Regulatory Class:	II
Product Code:	JIT

3. Predicate Device

Abbott® ARCHITECT Tacrolimus Test System - K070820 Dimension® Tacrolimus Calibrator – K060503 Reference Device: LC/MS -MS Assay for Tacrolimus

4. Guidance Document(s):

"Class II Special Controls Guidance Document: Cyclosporine and Tacrolimus Assays; Guidance for Industry and FDA" 11/16/2002

"Bundling Multiple Devices or Multiple Indications in a Single Submission" - 06/22/2007

"The 510(k) Program: Evaluating Substantial Equivalence in Premarket Notifications [510(k)] Guidance for Industry and Food and Drug Administration Staff" 7/28/2014

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5. Device Description(s):

Dimension Tacrolimus Flex® Reagent Cartridge (TAC)

Dimension® system mixes and lyses the whole blood sample in the presence of pretreatment reagent 1. This reagent contains a displacer which acts to displace tacrolimus in the sample from binding proteins. The lysed sample is then mixed with the antibody enzyme conjugate. The tacrolimus present in the sample is bound by the tacrolimus antibody. Magnetic particles coated with tacrolimus are added to bind free (unbound) antibody-enzyme conjugate. The reaction mixture is then separated magnetically. Following separation, the supernatant containing the tacrolimus-antibody-enzyme complex is transferred to a cuvette and mixed with the substrate; chlorophenol red ß-d-galactopyranoside (CPRG). ß-galactosidase catalyzes the hydrolysis of CPRG to produce chlorophenol red (CPR) that absorbs light maximally at 577 nm. The change in absorbance at 577 nm due to the formation of CPR is directly proportional to the amount of tacrolimus in the patient's sample and is measured using a bichromatic (577, 700 nm) rate technique.

TACR+Ab-β-gal	→ TACR-Ab-β-gal + Ab-β+gal
TACR-Ab-β-gal + Ab-β-gal + CrO2-TACR	Magnetic separation → TACR-Ab-β-gal (transferred to cuvette)
CPRG (non-absorbing at 577 nm)	→ TACR-Ab-β-gal → CPR (absorbs at 577 nm)

If the calculated tacrolimus concentration in the patient sample exceeds 20 ng/mL, the test is automatically repeated using pretreatment reagent 2 in place of pretreatment reagent 1. Pretreatment reagent 2 does not contain the displacer so the signal produced represents nonanalyte signal. If significant signal is detected during the second analysis, the potential exists that interference from non-specific signal has impacted the accuracy of the initial test. In this situation, the reported test result is suppressed and replaced by a non-reportable test result message.

The reagents for the Tacrolimus assay are packaged in an 8-well Flex® Reagent Cartridge represented (top view) in the drawing below:

1	2	3	4	5	6	7	8
---	---	---	---	---	---	---	---

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The reagent placement is as follows:

Wellsa	Form	Ingredient	Concentrationb	Source
1	Liquid	Ab-β-galactosidase	c	mouse,monoclonal
2	Liquid	Pretreatment reagent 2
3,4	Tabletsd	Tacrolimus-CrO2	36 mg/tab
5,6	Tabletsd	CPRG	9.3 mg/tablet
7	Liquid	Substrate diluent
8	Liquid	Pretreatment reagent 1

Reagent Placement Dimension® Tacrolimus Flex® Reagent Cartridge

Wells are numbered consecutively from the wide end of the cartridge. a.

b. Nominal value in hydrated cartridge.

Antibody titer and conjugate activity may vary from lot to lot. C.

Tablets contain excipients, buffers, and stabilizers. d.

Dimension Tacrolimus Calibrator (TAC CAL)

6. Intended Use/ Indications for Use

Dimension Tacrolimus Flex® Reagent Cartridge (TAC)

The Dimension® Tacrolimus Flex Reagent Cartridge (TAC) method is an in vitro diagnostic test for the quantitative measurement of tacrolimus in human whole blood on the Dimension® clinical chemistry system.

Measurements of tacrolimus are used as an aid in the management of tacrolimus therapy in renal and hepatic transplant patients.

Dimension Tacrolimus Calibrator (TAC CAL)

The Dimension® Tacrolimus Calibrator (TAC CAL) is an in vitro diagnostic product for the calibration of the Tacrolimus (TAC) method on the Dimension® clinical chemistry system.

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7. Comparison of Technological Characteristics

A comparison summary of the features of the products is included in the following table.

Item	DeviceDimension Tacrolimus Flex®Reagent Cartridge (TAC)	PredicateARCHITECT Tacrolimus Assay(K070820)
Similarities
Intended Use	an in vitro diagnostic test for thequantitative measurement oftacrolimus in human whole blood	an in vitro diagnostic test for thequantitative measurement oftacrolimus in whole blood.
Indications for Use	used as an aid in the managementof tacrolimus therapy in renal andhepatic transplant patients	used as an aid in the managementof liver and kidney allograft patientsreceiving tacrolimus therapy
Sample Types	Whole blood in EDTA	Whole blood in EDTA
High Sample Dilution	Manual	Manual
Assay Type	Immunoassay	Immunoassay
Differences
Instrument	The Dimension® clinical chemistrysystem.	The Abbott ARCHITECT iSystem
Sample Pretreatment	No manual pretreatment	Manual pre-treatment
Cross reactivity Profile
M-I	1%	8%
M-II	18%	94%
M-III	15%	45%
M-IV	99%	9%
M-V	1%	Not Available
M-VI	1%	Not Available
M-VII	43%	Not Available
M-VIII	0%	Not Available
Measuring Range	1.0 - 30 ng/mL	2 - 30 ng/mL

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Calibrator:
Item	DeviceDimension Tacrolimus Calibrator	PredicateTACR CAL (K060503)
Similarities
Intended Use	An in vitro diagnostic product forthe calibration of the Tacrolimus(TAC) method on the Dimension®clinical chemistry system.	An in vitro diagnostic productintended to be used tocalibrate the Tacrolimusmethod (TACR) for theDimension® clinical chemistrysystem.
Form	Frozen Liquid	Frozen Liquid
Matrix	Whole blood hemolysate	Whole blood hemolysate
Levels	Five	Five
Traceability	Purified tacrolimus	Purified tacrolimus
Differences
Assignment	Assigned for Dimension® TAC	Assigned for Dimension®TACR
Target ConcentrationRange	Level 1: - 0.5 to + 0.5 ng/mLLevel 2: 2.7 to 4.2 ng/mLLevel 3: 5.8 to 7.3 ng/mLLevel 4: 11.6 to 13.6 ng/mLLevel 5: ≥30.0 ng/mL	Level A: - 0.7 to + 0.7 ng/mLLevel 2: 2.5 to 4.0 ng/mLLevel 3: 5.5 to 7.0 ng/mLLevel 4: 11.0 to 13.0 ng/mLLevel 5: 31.0 to 34.0 ng/mL

8. Performance Data

Precision

Reproducibility testing was conducted for the Dimension ® TAC method, at two external evaluation sites in addition to our internal testing. This testing was done in accordance with the CLSI/NCCLS Approved Guideline for User Evaluation of Precision Performance of Clinical Chemistry Devices EP5-A2. Typical precision at levels ranging from a mean of 1.8 to 27.4 ng/mL was ≤ 6.6% CV for Repeatability and ≤ 13.1% CV for Within Lab.

Linearity

The analytical measuring range of the TAC method was confirmed by the establishment of the Limit of Quantitation (LoQ), for the low end, and by a linearity study. The linearity study was performed by mixing of a sample with a known native high tacrolimus concentration (40.3 ng/mL) with a normal patient pool with no tacrolimus in various ratios. The testing procedure was based on the CLSI Guideline EP 06-A Evaluation of the Linearity of Quantitative Measurement. A linear regression, and a 200 - and 35 -order polynomial regressions of the mean observed analyte values vs. expected concentrations were performed. The assay range for the Dimension® TAC method was established as 1.0 - 30.0 ng/mL by these two studies.

Specificity

Interference and cross-reactivity testing was performed according to CLSI/NCCLS Approved Guideline Interference Testing in Clinical Chemistry: EP7-A2. The compounds tested included endogenous compounds, drugs that are commonly co-administered with tacrolimus, and the anticoagulant EDTA. The cross-reactivity testing was done with major tacrolimus metabolite, M I (13-O-desmethyl-tacrolimus), M II (31-O-desmethyl-tacrolimus); as well as minor metabolites M III (15-O-desmethyl-tacrolimus), M IV (12-O-hydroxyl-tacrolimus), M V (15,31-O-didesmethyltacrolimus); and second pass metabolites, M VI (13,31-O-didesmethyl-tacrolimus), M VII (13,15-O-didesmethyl-tacrolimus) and M VIII(unknown name). Testing was done as recommended in the FDA Guidance document "Class II Special Controls Guidance Document: cyclosporine and Tacrolimus Assays; Guidance for Industry and FDA" – 09/16/2002. These studies showed that the Dimension® TAC method has low cross-reactivity to the major (M-1) tacrolimus metabolite,

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and partial cross reactivity to the minor and second pass metabolites of lower prevalence. Coadministered drugs and other compounds tested for interference, exhibited less than 10% bias at the levels tested.

Recovery

The recovery capability of the Dimension® TAC assay was challenged across the assay range using samples spiked with USP tacrolimus. All samples met the acceptance criterion of ≤ 10% mean bias in recovery.

Method Comparison

A method comparison study was performed at two external evaluation sites and internally per the "FDA Class II Special Controls Guidance document: Cyclosporine and Tacrolimus Assays: Guidance for Industry and FDA". Samples included a nearly equal distribution of liver and kidney transplant patients which covered >80% of the assay range (1.0 - 30 ng/mL). CLSI Guideline EP-9A2 "Method Comparison and Bias Estimation using Patient Samples" was used to develop the study design.

As recommended by the guidance, samples were evaluated, at two external sites as well as internally, versus the predicate, ARCHITECT Tacrolimus Assay (K070820), and an LCMS reference method. An additional comparative method. Dimension® TACR, was also run at two sites. Analysis was done by Passing - Bablok regression. Least Squares regression was used to compute the correlation coefficient.

Dimension Tacrolimus (TAC)	Slope	Intercept	r	n	Range
method vs					(ng/mL)
Reference Method LC-MS/MS	1.04	-0.30	0.966	315	1.3-24.9
ARCHITECT Tacrolimus Assay(K070820)	0.99	-0.42	0.979	308	2.1-24.2
Dimension Tacrolimus (TACR) method(K060502)	1.00	-0.50	0.957	213	2.6 - 21.7

The samples range for the proposed Dimension TAC assay, in these studies, was 1.2 - 25.6 ng/mL.

Calibrator Traceability

Siemens Tacrolimus (TAC) Calibrator is traceable to purified tacrolimus drug through standardization of the LC-MS/MS reference method with gravimetrically prepared standards.

Calibrator Stability

Unopened vials of Siemens Tacrolimus (TAC) Calibrator are stored frozen (-25 to -15 °C) until the expiration date printed on each carton. Once thawed, assigned values are stable for 30 days when recapped immediately after use and stored at 2-8°C.

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9. Conclusion:

The Siemens Healthcare Diagnostics Dimension® TAC method and the ARCHITECT Tacrolimus Assay (K070820) are substantially equivalent based on their intended use, indications for use and performance characteristics. In performance studies, summarized above, the Dimension® Tacrolimus methods demonstrated performance similar to the predicate ARCHITECT Tacrolimus Assay (K070820).

The modified Siemens Healthcare Diagnostics Dimension ® TAC calibrator and the predicate Dimension® TACR calibrator (K060503) are also substantially equivalent in design, intended use, principle and performance.

Anna Marie Kathleen Ennis Regulatory Affairs Manager

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Regulation Number and Section

§ 862.1678 Tacrolimus test system.

(a)
Identification. A tacrolimus test system is a device intended to quantitatively determine tacrolimus concentrations as an aid in the management of transplant patients receiving therapy with this drug. This generic type of device includes immunoassays and chromatographic assays for tacrolimus.(b)
Classification. Class II (special controls). The special control is “Class II Special Controls Guidance Document: Cyclosporine and Tacrolimus Assays; Guidance for Industry and FDA.” See § 862.1(d) for the availability of this guidance document.