(221 days)
The Alinity c Tricyclic Antidepressants Reagent Kit is a homogeneous enzyme immunoassay intended for use in the qualitative and/or semiquantitative determination of the presence of tricyclic antidepressants (TCAs) in human serum or plasma at a cutoff concentration of 300 ng/mL on the Alinity c system in patients suspected of drug overdose.
The semiquantitative mode is for the purpose of enabling laboratories to determine an appropriate dilution of the specimen for confirmation by confirmatory method such as Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS), or for permitting laboratories to establish control procedures.
The assay provides only a preliminary analytical test result. A more specific alternative chemical method must be used to obtain a confirmed analytical result. Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS) is the preferred confirmatory method.
Clinical and professional judgment should be applied to any drug of abuse test result, particularly when preliminary positive results are used.
For In Vitro Diagnostic Use Only.
The Alinity c Tricyclic Antidepressants Reagent Kit is an automated clinical chemistry assay and a homoqeneous enzyme immunoassay using ready-to-use liquid reagents. The assay uses polyclonal antibodies that detect most tricyclic antidepressants in serum or plasma. The assay is based on the competition between an enzyme-labeled drug and the drug from the serum or plasma for a fixed number of specific antibody binding sites. In the absence of drug from the sample, the specific antibody binds to the drug labeled with glucose-6-phosphate dehydrogenase (G6PDH) and the enzyme activity is inhibited. This phenomenon creates a direct relationship between the drug concentration in the serum or plasma and the enzyme activity. The G6PDH enzyme activity is determined spectrophotometrically at 340/416 nm by measuring its ability to convert nicotinamide adenine dinucleotide (NAD) to NADH.
The Alinity c Tricyclic Antidepressants Reagent Kit is supplied as a two liquid reagent kit (R1 and R2). They are included within the same kit, see details below:
- Antibody/Substrate Reagent (R1): Contains polyclonal anti-tricyclics antibodies ● (sheep), glucose-6- phosphate (G6P), and nicotinamide adenine dinucleotide (NAD) in Tris buffer with sodium azide as a preservative.
- Enzyme Conjugate Reagent (R2): Contains glucose-6-phosphate dehydrogenase (G6PDH) labeled with nortriptyline in Tris buffer with sodium azide as a preservative.
Here's the breakdown of the acceptance criteria and study information for the Alinity c Tricyclic Antidepressants Reagent Kit, based on the provided document:
1. Table of Acceptance Criteria and Reported Device Performance
The document doesn't explicitly state "acceptance criteria" as a separate predefined table for each test. Instead, the performance studies themselves imply the acceptance criteria by demonstrating successful results within expected ranges for each analytical parameter. I've synthesized these based on common analytical performance expectations and the reported findings.
| Study Parameter | Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|---|
| a) Precision (Repeatability) | Consistent qualitative/semi-quantitative results across replicates and runs. No significant outliers. | At or below -25% cutoff (225 ng/mL), all 80 replicates were Negative. At or above +25% cutoff (375 ng/mL), all 80 replicates were Positive. At cutoff (300 ng/mL), 54/26 (Qualitative) and 56/24 (Semi-Quantitative) Negative/Positive results respectively. |
| a) Precision (Reproducibility) | Consistent qualitative/semi-quantitative results across multiple instruments, lots, and runs. | At or below -25% cutoff (225 ng/mL), all 75 replicates were Negative. At or above +25% cutoff (375 ng/mL), all 75 replicates were Positive. At cutoff (300 ng/mL), 40/35 (Qualitative) and 49/26 (Semi-Quantitative) Negative/Positive results respectively. |
| b) Spike Recovery | Accurate detection of spiked low and high control samples. | Low Control (225 ng/mL): All 20 replicates were Negative. High Control (375 ng/mL): All 20 replicates were Positive. No overlap between low and high controls. |
| c) Dilution Linearity | Mean Recovery (%) generally within an acceptable range (e.g., 80-120%). | Mean recovery values ranged from 98% to 118% across 9 concentration levels (0 to 500 ng/mL). |
| d) Method Comparison and Accuracy (Serum) | High agreement with LC-MS/MS, especially near and above cutoff. Low false positive/negative rates. | % Negative Sample Agreement: 96% (48/50). % Positive Sample Agreement: 100% (50/50). % Total Sample Agreement: 98% (98/100). |
| e) Matrix Equivalency | Consistent qualitative/semi-quantitative results across different plasma matrices compared to serum. | K2 EDTA, K3 EDTA, Lithium Heparin, Sodium Citrate, Potassium Oxalate, and Sodium Heparin Plasma all showed 25 Positive and 25 Negative results, matching the expected outcome based on the spiked samples. |
| f) Specificity (Cross-Reactivity) | Predictable cross-reactivity with structurally related compounds as expected for TCA assays. Minimal to no clinically significant cross-reactivity with structurally unrelated compounds. | Structurally Related TCAs: Wide range of cross-reactivity (e.g., Amitriptyline 100%, Imipramine 157.9%, Desipramine 107.1%). Other Drugs: Varied cross-reactivity for some (e.g., Chlorpromazine 60%, Cyclobenzaprine 80%), indicating potential for interference. Structurally Unrelated Compounds: Minimal cross-reactivity at specified concentrations, with no impact on samples spiked at -25% and +25% of cutoff. Carbamazepine noted as a specific limitation causing unconfirmed positive results at high concentrations (>3000 ng/mL). |
| g) Interference | Endogenous and exogenous substances should not interfere with accurate qualitative/semi-quantitative results. | Controls (225 ng/mL and 375 ng/mL) were detected accurately (Negative and Positive, respectively) in the presence of tested conjugated/unconjugated bilirubin, hemoglobin, HSA, y-globulin, Rh Factor, triglycerides, and cholesterol at specified concentrations. |
2. Sample Size Used for the Test Set and Data Provenance
- Precision Studies (Repeatability): 80 replicates for each of 7 concentration levels (total 560 samples) for qualitative and semi-quantitative modes.
- Precision Studies (Reproducibility): 75 replicates for each of 7 concentration levels (total 525 samples) for qualitative and semi-quantitative modes.
- Spike Recovery: 20 replicates for Low Control (225 ng/mL) and 20 replicates for High Control (375 ng/mL).
- Dilution Linearity: 5 replicates for each of 9 concentration levels (total 45 samples).
- Method Comparison and Accuracy: 50 negative and 50 positive patient specimens (total 100 patient specimens).
- Matrix Equivalency: 50 patient samples (analyzed in 2 replicates each, across 6 different plasma matrices).
- Specificity (Cross-Reactivity): Varies per compound, generally by spiking known amounts into drug-free serum.
- Interference: Low control (225 ng/mL) and high control (375 ng/mL) samples were spiked with various interfering substances.
Data Provenance: The document does not explicitly state the country of origin for the data or whether the patient specimens were retrospective or prospective. It refers to "patient specimens" without further detail on their origin or collection method.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The document states that the test results were "Compared to LC-MS/MS lab testing." LC-MS/MS (Liquid Chromatography/Tandem Mass Spectrometry) is generally considered the gold standard confirmatory method for drug analyses. Therefore, the ground truth was established by this highly specific and sensitive analytical technique, rather than by human expert consensus or pathology in the traditional sense. The document does not specify the number or qualifications of individuals who performed or interpreted the LC-MS/MS tests; it's assumed to be performed by qualified laboratory personnel.
4. Adjudication Method (for the test set)
Ground truth was established by LC-MS/MS, which is an objective chemical analysis method. Therefore, no human adjudication method (like 2+1 or 3+1) was used or needed for establishing the ground truth. Discordant samples were further investigated using additional LC-MS analysis to assess the root cause, indicating a scientific investigation of discrepancies rather than a consensus-based adjudication.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No MRMC comparative effectiveness study was done. This device is an automated clinical chemistry assay, an in vitro diagnostic (IVD) reagent kit, and not an AI-powered diagnostic imaging device involving human readers. Therefore, there's no "human readers improve with AI vs. without AI assistance" effect size to report.
6. Standalone Performance Study
Yes, a standalone performance study was done. All the analytical performance studies (Precision, Spike Recovery, Dilution Linearity, Method Comparison, Matrix Equivalency, Specificity, Interference) evaluate the performance of the Alinity c Tricyclic Antidepressants Reagent Kit (i.e., the algorithm/reagent system) independently. The results reported are the performance of the device without human interpretation affecting the primary quantitative or qualitative output of the assay.
7. Type of Ground Truth Used
The primary ground truth used for performance evaluation, particularly for method comparison and accuracy, was LC-MS/MS (Liquid Chromatography/Tandem Mass Spectrometry) results. LC-MS/MS is considered a definitive confirmatory method for drug concentrations.
8. Sample Size for the Training Set
The document does not provide information about a "training set" in the context of machine learning or AI. This device is described as a "homogeneous enzyme immunoassay" using "polyclonal antibodies." This indicates a traditional biochemical assay technology, not a machine learning model that requires a dedicated training set. Therefore, this question is not applicable to the technology described.
9. How the Ground Truth for the Training Set Was Established
As noted in point 8, this device does not appear to be an AI/ML-based system requiring a training set. If there were any internal development or calibration processes that involved data, the document does not specify them or their ground truth establishment. For traditional IVD assays, performance is typically validated against reference methods and known standards.
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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, which is a blue square with the letters "FDA" in white. To the right of the blue square is the text "U.S. FOOD & DRUG ADMINISTRATION" in blue.
Microgenics Corporation Thermo Fisher Scientific Pranjali Shinde Manager, Regulatory Affairs 46500 Kato Road Fremont, California 94538
Re: K231020
Trade/Device Name: Alinity c Tricyclic Antidepressants Reagent Kit Regulation Number: 21 CFR 862.3910 Regulation Name: Tricyclic Antidepressant Drugs Test System Regulatory Class: Class II Product Code: LFH Dated: October 11, 2023 Received: October 13, 2023
Dear Pranjali Shinde:
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 (the 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 available 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.
Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device"
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(https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).
Your device is also subject to, among other requirements, the Quality System (QS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30. Design controls; 21 CFR 820.90. Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review. the OS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).
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 Part 801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safetyreporting-combination-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 Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 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.
Digitally signed by Joseph A. Joseph A. Kotarek -S Date: 2023.11.17 Kotarek -S 16:52:07 -05'00'
Joseph Kotarek Branch Chief Division of Chemistry
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and Toxicology Devices OHT7: Office of In Vitro Diagnostics 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) K231020
Device Name
Alinity c Tricyclic Antidepressants Reagent Kit
Indications for Use (Describe)
The Alinity c Tricyclic Antidepressants Reagent Kit is a homogeneous enzyme immunoassay intended for use in the qualitative and/or semiquantitative determination of the presence of tricyclic antidepressants (TCAs) in human serum or plasma at a cutoff concentration of 300 ng/mL on the Alinity c system in patients suspected of drug overdose.
The semiquantitative mode is for the purpose of enabling laboratories to determine an appropriate dilution of the specimen for confirmation by confirmatory method such as Liquid Chromatography/Tandem Mass Spectrometry (1.C-MS/MS), or for permitting laboratories to establish control procedures.
The assay provides only a preliminary analytical test result. A more specific alternative chemical method must be used to obtain a confirmed analytical result. Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS) is the preferred confirmatory method.
Clinical and professional judgment should be applied to any drug of abuse test result, particularly when preliminary positive results are used.
For In Vitro Diagnostic Use Only.
| 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
510(k) Number: K231020
This 510(k) Summary of Safety and Effectiveness is being submitted in accordance with the requirements of Safe Medical Device Act of 1990 and 21 CFR 807.92.
A. Device Information
| Sponsor: | Microgenics CorporationThermo Fisher Scientific46500 Kato RoadFremont, CA 94538Phone: 510-979-5000Fax: 510-979-5002 |
|---|---|
| Correspondent ContactInformation: | Pranjali ShindeMicrogenics CorporationThermo Fisher Scientific46500 Kato RoadFremont, CA-94538Email: Pranjali.Shinde@Thermofisher.comPhone: 510-979-5000Fax: 510-979-5002 |
| Device Common Name: | Alinity c Tricyclic Antidepressants Reagent Kit |
| Trade or Proprietary Name | Alinity c Tricyclic Antidepressants Reagent Kit |
| Brand Name | Alinity c Tricyclic Antidepressants Reagent Kit |
| Candidate Device ProductCode, Classification,Classification Name & Panel | LFH, Class II,21 CFR 862. 3910 - Tricyclic antidepressant drugstest system, 91 - Toxicology |
Predicate Device Information:
| Predicate Device: | DRI Tricyclics Serum Tox Assay |
|---|---|
| Predicate Device Manufacturer: | Microgenics Corporation |
| Predicate Device Common Name | Tricyclics Serum Tox Assay |
| Predicate Device Premarket Notification #: | K213875 |
| Predicate Device Product Code, Classification, Classification Name & Panel | LFH, Class II,21 CFR 862. 3910 - Tricyclic antidepressant drugs testsystem, 91 – Toxicology |
B. Date Summary Prepared
November 17, 2023
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C. Description of Device
The Alinity c Tricyclic Antidepressants Reagent Kit is an automated clinical chemistry assay and a homoqeneous enzyme immunoassay using ready-to-use liquid reagents. The assay uses polyclonal antibodies that detect most tricyclic antidepressants in serum or plasma. The assay is based on the competition between an enzyme-labeled drug and the drug from the serum or plasma for a fixed number of specific antibody binding sites. In the absence of drug from the sample, the specific antibody binds to the drug labeled with glucose-6-phosphate dehydrogenase (G6PDH) and the enzyme activity is inhibited. This phenomenon creates a direct relationship between the drug concentration in the serum or plasma and the enzyme activity. The G6PDH enzyme activity is determined spectrophotometrically at 340/416 nm by measuring its ability to convert nicotinamide adenine dinucleotide (NAD) to NADH.
The Alinity c Tricyclic Antidepressants Reagent Kit is supplied as a two liquid reagent kit (R1 and R2). They are included within the same kit, see details below:
- Antibody/Substrate Reagent (R1): Contains polyclonal anti-tricyclics antibodies ● (sheep), glucose-6- phosphate (G6P), and nicotinamide adenine dinucleotide (NAD) in Tris buffer with sodium azide as a preservative.
- Enzyme Conjugate Reagent (R2): Contains glucose-6-phosphate dehydrogenase (G6PDH) labeled with nortriptyline in Tris buffer with sodium azide as a preservative.
D. Intended Use
The Alinity c Tricyclic Antidepressants Reagent Kit is a homogeneous enzyme immunoassay intended for use in the qualitative and/or semiguantitative determination of the presence of tricyclic antidepressants (TCAs) in human serum or plasma at a cutoff concentration of 300 ng/mL on the Alinity c system in patients suspected of drug overdose.
The semiquantitative mode is for the purpose of enabling laboratories to determine an appropriate dilution of the specimen for confirmation by confirmatory method such as Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS), or for permitting laboratories to establish control procedures.
The assay provides only a preliminary analytical test result. A more specific alternative chemical method must be used to obtain a confirmed analytical result. Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS) is the preferred confirmatory method.
Clinical and professional judgment should be applied to any drug of abuse test result. particularly when preliminary positive results are used.
For In Vitro Diagnostic Use Only.
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E. Comparison to Predicate Device
| Characteristics | Candidate Device:Alinity c Tricyclic AntidepressantsReagent Kit | Predicate Device:DRI Tricyclics Serum Tox Assay(K213875) |
|---|---|---|
| Intended Use | The Alinity c TricyclicAntidepressants Reagent Kit is ahomogeneous enzymeimmunoassay intended for use inthe qualitative and/orsemiquantitative determination ofthe presence of tricyclicantidepressants (TCAs) in humanserum or plasma at a cutoffconcentration of 300 ng/mL onthe Alinity c system in patientssuspected of drug overdose.The semiquantitative mode is forthe purpose of enablinglaboratories to determine anappropriate dilution of thespecimen for confirmation byconfirmatory method such asLiquid Chromatography/TandemMass Spectrometry (LC-MS/MS),or for permitting laboratories toestablish control procedures.The assay provides only apreliminary analytical test result.A more specific alternativechemical method must be usedto obtain a confirmed analyticalresult. LiquidChromatography/Tandem MassSpectrometry (LC-MS/MS) is thepreferred confirmatory method.Clinical and professionaljudgment should be applied toany drug of abuse test result,particularly when preliminarypositive results are used.For In Vitro Diagnostic Use Only. | The DRI ™ Tricyclics Serum ToxAssay is a homogeneous enzymeimmunoassay intended for thequalitative and/or semiquantitativedetermination of the presence oftricyclic antidepressants (TCAs) inhuman serum, plasma, or urine ofpatients at a cutoff concentrationof 300 ng/mL in patientssuspected of drug overdose.The semi-quantitative mode is forthe purpose of enablinglaboratories to determine anappropriate dilution of thespecimen for confirmation by aconfirmatory method such asLiquid Chromatography/TandemMass Spectrometry (LC-MS/MS)or permitting laboratories toestablish quality controlprocedures.The assay provides only apreliminary analytical test result. Amore specific alternative chemicalmethod must be used to obtain aconfirmed analytical result. LiquidChromatography/Tandem MassSpectrometry (LC-MS/MS) is thepreferred confirmatory method.Clinical and professional judgmentshould be applied to any drug ofabuse test result, particularly whenpreliminary positive results areused.For In Vitro Diagnostic Use Only. |
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| OperatingPrinciple(Technology) | DRI | Same |
|---|---|---|
| Measured Analyte | Nortriptyline | Same |
| Test Matrix | Serum, Plasma | Serum, Plasma, Urine |
| Cut-off Levels | 300 ng/mL | Same |
| Methodology | Homogeneous EnzymeImmunoassay | Same |
| Reagents Form | Liquid ready-to-use. | Same |
| Antibody | Sheep polyclonal antibodies | Same |
| Storage | 2-8 °C until expiration date. | Same |
| Principal Operator | Trained professionals | Same |
| Calibrator Levelsfor Semi-Quant | 4-point Calibrator | 5-point Calibrator |
F. Test Principle
The Alinity c Tricyclic Antidepressants Reagent Kit is an automated clinical chemistry assay and a homogeneous enzyme immunoassay using ready-to-use liquid reagents. The assay uses polyclonal antibodies that detect most tricyclic antidepressants in serum or plasma. The assay is based on the competition between an enzyme-labeled drug and the drug from the serum or plasma for a fixed number of specific antibody binding sites. In the absence of drug from the sample, the specific antibody binds to the drug labeled with glucose-6-phosphate dehydrogenase (G6PDH) and the enzyme activity is inhibited. This phenomenon creates a direct relationship between the drug concentration in the serum or plasma and the enzyme activity. The G6PDH enzyme activity is determined spectrophotometrically at 340/416 nm by measuring its ability to convert nicotinamide adenine dinucleotide (NAD) to NADH.
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G. Summary of Supporting Data
Analytical Performance:
The performance was evaluated on Alinity c clinical chemistry analyzer.
- a) Precision
Precision study is performed in accordance with CLSI Guideline EP05-A3.
Samples were prepared by spiking Nortriptyline in drug-free serum at final concentrations of -100%, -75%, -50%, -25% below cutoff, cutoff and +25%, +50% above cutoff. .
Repeatability:
The study was conducted for 20 days with 2 runs per day, 2 replicates per run in both qualitative and semi-quantitative modes with 1 lot of reagent, calibrators, and controls. There were 80 replicates for each level of precision samples. The results of the precision study (Repeatability) are presented in the table below.
| SpikedConcentration(ng/mL) | % ofCutoff | Total Precision (n=80)for 300 ng/mL cutoff – Serum | ||
|---|---|---|---|---|
| # ofDeterminants | QualitativeImmunoassayResults(Negative/Positive) | Semi-QuantitativeImmunoassayResults(Negative/Positive) | ||
| 0 | -100 | 80 | 80/0 | 80/0 |
| 75 | -75 | 80 | 80/0 | 80/0 |
| 150 | -50 | 80 | 80/0 | 80/0 |
| 225 | -25 | 80 | 80/0 | 80/0 |
| 300 | 100 | 80 | 54/26 | 56/24 |
| 375 | +25 | 80 | 0/80 | 0/80 |
| 450 | +50 | 80 | 0/80 | 0/80 |
Table 1: Precision study data (Repeatability) in qualitative and semi-quantitative mode
Reproducibility:
The study was conducted for 5 days with 1 run per day, 5 replicates per run in both qualitative and semi-quantitative modes with 2 lots of reagents on 3 different instruments. The results of the precision study (Reproducibility) are presented in the table below.
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| % ofCutoff | # ofDeterminants | Total Precision (n=75) – Serum | ||
|---|---|---|---|---|
| SpikedConcentration(ng/mL) | QualitativeImmunoassayResults(Negative/Positive) | Semi-quantitativeImmunoassayResults(Negative/Positive) | ||
| 0 | -100 | 75 | 75/0 | 75/0 |
| 75 | -75 | 75 | 75/0 | 75/0 |
| 150 | -50 | 75 | 75/0 | 75/0 |
| 225 | -25 | 75 | 75/0 | 75/0 |
| 300 | 100 | 75 | 40/35 | 49/26 |
| 375 | +25 | 75 | 75/0 | 75/0 |
| 450 | +50 | 75 | 75/0 | 75/0 |
Table 2: Precision study data (Reproducibility) in qualitative and semi-quantitative mode for
b) Spike Recovery
The spike recovery study was performed using 20 replicates. Samples were prepared by spiking Nortriptyline in drug-free serum at 225 ng/mL, 300 ng/mL, 375 ng/mL. The study demonstrated the accuracy of spike recovery at low control (225 ng/mL) and high control (375 ng/mL) in both qualitative and semi-quantitative mode. The results of the study are presented in the table below.
Table 3: Spike Recovery in qualitative and semi-quantitative mode for 300 ng/mL cutoff – Serum
| Replicates | Low Control: 225 ng/mL(-25% of cutoff) (n=20) | High Control: 375 ng/mL(+25% of cutoff)(n=20) |
|---|---|---|
| 1 | Negative | Positive |
| 2 | Negative | Positive |
| 3 | Negative | Positive |
| 4 | Negative | Positive |
| 5 | Negative | Positive |
| 6 | Negative | Positive |
| 7 | Negative | Positive |
| 8 | Negative | Positive |
| 9 | Negative | Positive |
| 10 | Negative | Positive |
| 11 | Negative | Positive |
| 12 | Negative | Positive |
| 13 | Negative | Positive |
| 14 | Negative | Positive |
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| Replicates | Low Control: 225 ng/mL(-25% of cutoff) (n=20) | High Control: 375 ng/mL(+25% of cutoff)(n=20) |
|---|---|---|
| 15 | Negative | Positive |
| 16 | Negative | Positive |
| 17 | Negative | Positive |
| 18 | Negative | Positive |
| 19 | Negative | Positive |
| 20 | Negative | Positive |
| Overlap | No | No |
| Relative toC/O | All 20 below C/O | All 20 above C/O |
c) Dilution Linearity
The Dilution Linearity study is performed in accordance with CLSI Guideline EP06-Ed2.
To demonstrate the dilution linearity for purposes of sample dilution and quality control of the entire assay range, drug-free serum was spiked using Nortriptyline and diluted with drug-free serum to generate 9 levels between 0 and 500 ng/mL. Each sample was run in replicates of 5 in semi-quantitative mode and the average was used to determine percent recovery compared to the expected target value. The study results are presented in the table below.
| Level | Expectedconcentration(ng/mL) | Average of observedconcentration (ng/mL)(N=5) | Mean Recovery (%) |
|---|---|---|---|
| 1 | 0 | 5 | N/A |
| 2 | 62.5 | 74 | 118 |
| 3 | 125.0 | 144 | 115 |
| 4 | 187.5 | 210 | 112 |
| 5 | 250.0 | 260 | 104 |
| 6 | 312.5 | 310 | 99 |
| 7 | 375.0 | 393 | 105 |
| 8 | 437.5 | 453 | 104 |
| 9 | 500 | 492 | 98 |
Table 4: Dilution linearity data in Serum
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- d) Method Comparison and Accuracy
The method comparison study is performed in accordance with CLSI guideline EP07-A3, EP09c-A3 & EP12-A.
One (1) replicate of each of the 50 negative and 50 positive patient specimens were analyzed in both qualitative and semi-quantitative modes. Results were compared to LC-MS/MS lab testing. The results of the study are presented in the tables below.
Table 5: Stratified data comparing immunoassay in qualitative mode with LC-MS/MS -
| Serum | |||||
|---|---|---|---|---|---|
| AlinityTCAAssayResults | Negativeby LC-MS/MS | < 50% ofCutoffconcentrationby LC-MS/MS (<150 ng/mL) | Near CutoffNegative(Between50% belowthe cutoff andthe cutoffconcentrationasdeterminedby LC-MS/MS)(150-299ng/mL) | Near CutoffPositive(Between thecutoff and50% abovethe cutoffconcentrationasdeterminedby LC-MS/MS)(300-450ng/mL) | HighPositives(Greater than50% abovecutoffconcentration(> 450ng/mL) |
| Positive | 0 | 21 | 0 | 38 | 12 |
| Negative | 0 | 19 | 29 | 0 | 0 |
| % Negative Sample Agreement | 96% or (48/50) | ||||
| % Positive Sample Agreement | 100% or (50/50) | ||||
| % Total Sample Agreement | 98% or (98/100) |
1 Refer to Table 7 for discordant samples of serum.
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| AlinityTCAAssayResults | Negativeby LC-MS/MS | < 50% ofCutoffconcentrationby LC-MS/MS (<150 ng/mL) | MS/MS - SerumNear CutoffNegative(Between50% belowthe cutoffand thecutoffconcentrationasdeterminedby LC-MS/MS)(150-299ng/mL) | Near CutoffPositive(Between thecutoff and50% abovethe cutoffconcentrationasdeterminedby LC-MS/MS)(300-450ng/mL) | HighPositives(Greater than50% abovecutoffconcentration(> 450ng/mL) |
|---|---|---|---|---|---|
| Positive | 0 | 21 | 0 | 38 | 12 |
| Negative | 0 | 19 | 29 | 0 | 0 |
| % Negative Sample Agreement | 96% or (48/50) | ||||
| % Positive Sample Agreement | 100% or (50/50) | ||||
| % Total Sample Agreement | 98% or (98/100) |
| Table 6: Stratified data comparing immunoassay in semi-quantitative mode with LC | ||||
|---|---|---|---|---|
| MONIO O |
1 Refer to Table 7 for discordant samples of serum.
| Table 7: Discordant Samples - Serum | |||
|---|---|---|---|
| -- | ------------------------------------- | -- | -- |
| Sample ID | Qualitative (°Δ mA/min)Result | Semi-QuantitativeObserved concentration(ng/mL) | LC-MS/MS Value(ng/mL) |
|---|---|---|---|
| APP9489-2 2 | Positive | 332 (Positive) | 104 |
| APP9474-2 3 | Positive | 323 (Positive) | 113 |
2 Sample APP9489-2 contains Amitriptyline at 8.08 ng/mL, Imipramine at 18.35 ng/mL, Desipramine at 46.35 ng/mL, and Nortriptyline at 17 ng/mL by LC-MS/MS and cross-reacts at 100%, 158%, 107%, and 100% by immunoassay respectively.
3 Sample APP9474-2 contains Amitriptyline at 9.08 ng/mL, Imipramine at 19.9 ng/mL, Desipramine at 49.8 ng/mL, and Nortriptyline at 19.65 ng/mL by LC-MS/MS and cross-reacts at 100%, 158%, 107%, and 100% by immunoassay respectively.
Additional Testing of discordant samples: Additional LC-MS analysis was performed on these two samples to assess root cause for the discordant result. In the final LC-MS/MS result, both samples, APP9489-2 and APP9474-2, detected positive by immunoassay contain Carbamazepine with concentrations of 4275 ng/mL and 595 ng/mL, respectively. Carbamazepine has been shown to cross-react in multiple antibody-based TCA immunoassays as documented in independent scientific literature (Section 22, References 19, 20, 21). In addition, this effect was demonstrated as part
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of cross-reactivity studies reported in CDD-FR-REC-7208 Alinity c Tricyclic Antidepressants Serum Tox Assay Non-Critical Cross Reactivity Report. Both discordant samples contain carbamazepine with concentration above 3000 ng/mL. which is sufficient to cause the unconfirmed positive result seen for these two samples. The cross-reactivity with carbamazepine is a limitation of the immunoassay.
- e) Matrix equivalency
Matrix Equivalency is performed in accordance with CLSI Guideline EP12-A2, EP35 & EP39 Ed-1.
Two (2) replicates of 50 patient samples were run in both qualitative and semiquantitative modes to demonstrate Nortriptyline concentrations obtained in different test plasma matrices with different anticoaqulants are equivalent to those measured in the primary or control matrix, serum. The results of the matrix equivalency study are presented in the table below.
| Serum Matrix | Qualitative | Semi- Quantitative | |||
|---|---|---|---|---|---|
| Positive | Negative | Positive | Negative | ||
| K2 EDTA Plasma | Positive | 25 | 0 | 25 | 0 |
| Negative | 0 | 25 | 0 | 25 | |
| K3 EDTA plasma | Positive | 25 | 0 | 25 | 0 |
| Negative | 0 | 25 | 0 | 25 | |
| Lithium Heparin Plasma | Positive | 25 | 0 | 25 | 0 |
| Negative | 0 | 25 | 0 | 25 | |
| Sodium Citrate Plasma | Positive | 25 | 0 | 25 | 0 |
| Negative | 0 | 25 | 0 | 25 | |
| Potassium Oxalate Plasma | Positive | 25 | 0 | 25 | 0 |
| Negative | 0 | 25 | 0 | 25 | |
| Sodium Heparin Plasma | Positive | 25 | 0 | 25 | 0 |
| Negative | 0 | 25 | 0 | 25 |
Table 8: Matrix Equivalency results in qualitative and semi-quantitative mode
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f) Specificity
Cross-Reactivity to structurally related compounds (Critical Cross-Reactivity): The cross-reactivity of Tricyclic compounds and other structurally related compounds were evaluated by adding known amount of each compound into drug-free serum at concentrations indicated. The results are summarized in the tables below.
| Table 9: Cross Reactivity to structurally related compounds in Serum (TCA and its metabolites) | |||
|---|---|---|---|
| Structurally RelatedCompounds | TestedConcentration(ng/mL) | Positive/Negative | CrossReactivity (%) |
| 2-Hydroxy imipramine | 1300 | Positive | 23.1% |
| 7-Hydroxy quetiapine | 100000 | Negative | < 0.3% |
| 7-Hydroxy amoxapinesolution | 100000 | Negative | < 0.3% |
| 8-Hydroxy amoxapinesolution | 100000 | Negative | < 0.3% |
| 10-Hydroxyamitriptyline | 1100 | Positive | 27.3% |
| Amitriptyline | 300 | Positive | 100% |
| Amoxapine | 200000 | Positive | 0.15% |
| Clomipramine | 325 | Positive | 92.3% |
| Desipramine | 280 | Positive | 107.1% |
| Dosulepin | 500 | Positive | 60.0% |
| Doxepin | 600 | Positive | 50.0% |
| Imipramine | 190 | Positive | 157.9% |
| Lofepramine | 440 | Positive | 68.1% |
| N-Desmethyltrimipramine | 325 | Positive | 92.3% |
| Norclomipraminehydrochloride | 375 | Positive | 80.0% |
| Nordoxepin hydrochloride | 2000 | Positive | 15.0% |
| Nortriptyline | 300 | Positive | 100.0% |
| Opipramol HCI | 350 | Positive | 85.7% |
| Protriptyline | 500 | Positive | 60.0% |
| Quetiapine fumarate | 55000 | Positive | 0.54% |
| Trimipramine | 400 | Positive | 75.0% |
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| Table 10: Cross Reactivity to structurally related compounds in Serum (other drugs) | |||
|---|---|---|---|
| Structurally Related Compounds | Tested Concentration (ng/mL) | Positive/Negative | Cross-reactivity (%) |
| Alimemazine | 10000 | Positive | 3.0% |
| Blonanserin | 100000 | Negative | < 0.3% |
| Chlorpromazine | 500 | Positive | 60.0% |
| Clozapine | 100000 | Negative | < 0.3% |
| Cyclobenzaprine | 375 | Positive | 80.0% |
| Desloratadine | 100000 | Negative | < 0.3% |
| Diphenhydramine | 60000 | Positive | 0.5% |
| Fluoxetine | 100000 | Negative | < 0.3% |
| Fluphenazine | 2000 | Positive | 15.0% |
| Haloperidol | 100000 | Negative | < 0.3% |
| Loratadine | 100000 | Negative | < 0.3% |
| Loxapine succinate | 100000 | Negative | < 0.3% |
| Maprotiline | 100000 | Positive | 0.3% |
| Mianserin | 100000 | Negative | < 0.3% |
| Mirtazapine | 100000 | Negative | < 0.3% |
| N-desmethylclozapine | 100000 | Negative | < 0.3% |
| N-Desmethylmirtazapine | 100000 | Negative | < 0.3% |
| Nefazodone | 100000 | Negative | < 0.3% |
| Normaprotiline | 100000 | Positive | 0.3% |
| Olanzapine | 100000 | Negative | < 0.3% |
| Paroxetine | 100000 | Negative | < 0.3% |
| Perphenazine | 450 | Positive | 66.7% |
| Phenoxybenzamine | 100000 | Negative | < 0.3% |
| Promazine | 450 | Positive | 66.7% |
| Promethazine | 20000 | Positive | 1.5% |
| Risperidone | 100000 | Negative | < 0.3% |
| Sertraline | 100000 | Negative | < 0.3% |
| Thioridazine | 5000 | Positive | 6.0% |
| Thiothixene | 100000 | Negative | < 0.3% |
| Tianeptine | 100000 | Negative | < 0.3% |
| Trazodone | 100000 | Negative | < 0.3% |
| Ziprasidone | 100000 | Negative | <0.3% |
| Table 10: Cross Reactivity to structurally related compounds in Serum (other drugs) | |||
|---|---|---|---|
| Structurally UnrelatedCompounds | TestedConcentration(ng/mL) | Compound Spikedinto Low Sample(225 ng/mL) | Compound Spikedinto High Sample(375 ng/mL) |
| 11-nor-Δ9-THC-COOH | 100000 | Negative | Positive |
| 6-Acetyl morphine | 75000 | Negative | Positive |
| Acetaminophen | 100000 | Negative | Positive |
| Acetylsalicylic acid | 100000 | Negative | Positive |
| Amisulpride | 100000 | Negative | Positive |
| Amoxicillin | 100000 | Negative | Positive |
| Amphetamine | 100000 | Negative | Positive |
| Benzotropine MethaneSulfonate | 3000 | Negative | Positive |
| Benzoylecgonine | 100000 | Negative | Positive |
| Brompheniramine | 3000 | Negative | Positive |
| Caffeine | 100000 | Negative | Positive |
| Carbamazepine | 3000 | Negative | Positive |
| Carbamazepine Epoxide | 10000 | Negative | Positive |
| Chloroquine phosphate | 100000 | Negative | Positive |
| Cimetidine | 100000 | Negative | Positive |
| Cocaine | 75000 | Negative | Positive |
| Codeine | 100000 | Negative | Positive |
| Dextromethorphan | 100000 | Negative | Positive |
| Diacetylmorphine (Heroin) | 100000 | Negative | Positive |
| Diazepam | 100000 | Negative | Positive |
| Digoxin | 100000 | Negative | Positive |
| Dihydrocodeine | 100000 | Negative | Positive |
| EDDP Perchlorate | 100000 | Negative | Positive |
| EMDP-HCL | 100000 | Negative | Positive |
| Fentanyl | 25000 | Negative | Positive |
| Glutethimide | 100000 | Negative | Positive |
| Hydrocodone | 100000 | Negative | Positive |
| Hydrocortisone | 100000 | Negative | Positive |
| Hydromorphone | 100000 | Negative | Positive |
| Hydroxyzine | 3000 | Negative | Positive |
| Ibuprofen | 100000 | Negative | Positive |
| Levorphanol | 100000 | Negative | Positive |
| Levothyroxine | 100000 | Negative | Positive |
| Structurally UnrelatedCompounds | TestedConcentration(ng/mL) | Compound Spikedinto Low Sample(225 ng/mL) | Compound Spikedinto High Sample(375 ng/mL) |
| Meperidine | 25000 | Negative | Positive |
| Methadone | 75000 | Negative | Positive |
| Methamphetamine | 100000 | Negative | Positive |
| Methaqualone | 500 | Negative | Positive |
| Methsuximide | 75000 | Negative | Positive |
| Methylphenidate | 100000 | Negative | Positive |
| Morphine | 100000 | Negative | Positive |
| Morphine-3β-glucuronide | 100000 | Negative | Positive |
| Morphine-6ß-glucuronide | 100000 | Negative | Positive |
| Nalbuphine | 100000 | Negative | Positive |
| Nalorphine | 100000 | Negative | Positive |
| Naloxone | 100000 | Negative | Positive |
| Naltrexone | 100000 | Negative | Positive |
| Naproxen | 100000 | Negative | Positive |
| Norcodeine | 100000 | Negative | Positive |
| Nordiazepam | 100000 | Negative | Positive |
| Norethindrone | 100000 | Negative | Positive |
| Norhydrocodone | 100000 | Negative | Positive |
| Noroxycodone | 100000 | Negative | Positive |
| Noroxymorphone | 100000 | Negative | Positive |
| Norpropoxyphene | 75000 | Negative | Positive |
| Oxaprozin | 100000 | Negative | Positive |
| Oxazepam | 100000 | Negative | Positive |
| Oxycodone | 100000 | Negative | Positive |
| Oxymorphone | 100000 | Negative | Positive |
| PCP | 25000 | Negative | Positive |
| Phenobarbital | 100000 | Negative | Positive |
| Phenytoin | 100000 | Negative | Positive |
| Primidone | 100000 | Negative | Positive |
| Procyclidine | 100000 | Negative | Positive |
| Propoxyphene | 100000 | Negative | Positive |
| Secobarbital | 100000 | Negative | Positive |
| Tapentadol | 100000 | Negative | Positive |
| Temazepam | 100000 | Negative | Positive |
| Triprolidine | 100000 | Negative | Positive |
| Valproic Acid | 100000 | Negative | Positive |
| Venlafaxine | 100000 | Negative | Positive |
| Verapamil | 100000 | Negative | Positive |
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Cross-reactivity to structurally unrelated compounds (Non-Critical Cross-Reactivity): Structurally unrelated compounds and/or concurrently used drugs were spiked at the concentration listed below into low and high controls (225 and 375 ng/mL) in serum. As shown in the table below the controls were detected accurately, with the low control as neqative and the high control as positive, indicating that all the compounds evaluated exhibited minimal cross-reactivity at the concentration tested. The study results are presented in the table below:
Table 11: Cross Reactivity to structurally unrelated compounds in Serum
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- g) Interference
The interference s study is performed in accordance with CLSI Guideline CLSI EP07-A3& EP37 ED1.
The potential interference of endogenous and exogenous substances on the recovery of nortriptyline using Alinity TCA Reagent Kit was assessed. Potentially interfering substances were spiked into the low control, 225ng/mL (-25% of the cutoff concentration of 300 ng/mL) and high controls, 375 ng/mL (+25% of the cutoff concentration of 300 ng/mL).
In the presence of the compounds listed below, the controls were detected accurately, indicating that these compounds did not show interference in the assay.
| Compounds | Tested Concentrations(mg/dL) | Low Control(225 ng/mL) | High Control(375 ng/mL) |
|---|---|---|---|
| Bilirubin (Conjugated) | 40 | Negative | Positive |
| Bilirubin (Unconjugated) | 40 | Negative | Positive |
| Hemoglobin | 1000 | Negative | Positive |
| Human Serum Albumin (HSA) | 7500 | Negative | Positive |
| y-globulin | 5000 | Negative | Positive |
| Rh Factor | 1300 IU | Negative | Positive |
| Triglycerides | 1500 | Negative | Positive |
| Cholesterol | 1400 | Negative | Positive |
Table 12: Results of Interfering Substances Testing - Serum
H. Conclusion
The information supports a determination of substantial equivalence between Alinity c Tricyclic Antidepressants Reagent kit and DRI Tricyclics Serum Tox Assay (K213875).
§ 862.3910 Tricyclic antidepressant drugs test system.
(a)
Identification. A tricyclic antidepressant drugs test system is a device intended to measure any of the tricyclic antidepressant drugs in serum. The tricyclic antidepressant drugs include imipramine, desipramine, amitriptyline, nortriptyline, protriptyline, and doxepin. Measurements obtained by this device are used in the diagnosis and treatment of chronic depression to ensure appropriate therapy.(b)
Classification. Class II (special controls). A tricyclic antidepressant drugs test system is not exempt if it is intended for any use other than employment or insurance testing or is intended for Federal drug testing programs. The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 862.9, provided the test system is intended for employment and insurance testing and includes a statement in the labeling that the device is intended solely for use in employment and insurance testing, and does not include devices intended for Federal drug testing programs (e.g., programs run by the Substance Abuse and Mental Health Services Administration (SAMHSA), the Department of Transportation (DOT), and the U.S. military).