(221 days)
Not Found
No
The device description and performance studies detail a standard enzyme immunoassay and spectrophotometric analysis, with no mention of AI or ML algorithms for data processing or interpretation.
No.
This device is an in vitro diagnostic (IVD) test intended for the qualitative and/or semiquantitative determination of tricyclic antidepressants in human serum or plasma. It provides an analytical test result for diagnostic purposes and does not directly provide therapy or treatment.
Yes
This device is a homogeneous enzyme immunoassay kit designed to qualitatively and/or semiquantitatively determine the presence of tricyclic antidepressants in human serum or plasma, specifically in patients suspected of drug overdose, making it a diagnostic tool.
No
The device is a reagent kit for an in vitro diagnostic assay, which is a physical product containing chemical reagents. It is not software.
Yes, this device is an IVD (In Vitro Diagnostic).
Here's why:
- Explicit Statement: The document explicitly states "For In Vitro Diagnostic Use Only" in the Intended Use section.
- Intended Use: The intended use is to determine the presence of tricyclic antidepressants in human serum or plasma, which are biological specimens taken from the body. This analysis is performed in vitro (outside the body).
- Device Description: The device is a reagent kit used in an automated clinical chemistry assay, which is a common method for performing in vitro diagnostic tests.
- Performance Studies: The performance studies involve analyzing patient specimens (serum and plasma) and comparing the results to a confirmatory method (LC-MS/MS), which is typical for validating an IVD.
N/A
Intended Use / Indications for Use
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.
Product codes (comma separated list FDA assigned to the subject device)
LFH
Device Description
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.
Mentions image processing
Not Found
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Not Found
Anatomical Site
Not Found
Indicated Patient Age Range
Not Found
Intended User / Care Setting
Trained professionals
Description of the training set, sample size, data source, and annotation protocol
Not Found
Description of the test set, sample size, data source, and annotation protocol
Not Found
Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)
Analytical Performance:
The performance was evaluated on Alinity c clinical chemistry analyzer.
a) Precision
Precision study 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.
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.
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.
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.
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.
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.
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.
Cross-reactivity to structurally unrelated compounds (Non-Critical Cross-Reactivity): Structurally unrelated compounds and/or concurrently used drugs were spiked at the concentration listed into low and high controls (225 and 375 ng/mL) in serum.
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).
Key results:
Method Comparison and Accuracy (Serum):
- Qualitative mode: % Negative Sample Agreement: 96% or (48/50), % Positive Sample Agreement: 100% or (50/50), % Total Sample Agreement: 98% or (98/100).
- Semi-quantitative mode: % Negative Sample Agreement: 96% or (48/50), % Positive Sample Agreement: 100% or (50/50), % Total Sample Agreement: 98% or (98/100).
- Two discordant samples (APP9489-2, APP9474-2) were positive by immunoassay but had low LC-MS/MS values. Further analysis showed presence of carbamazepine (4275 ng/mL and 595 ng/mL respectively) which cross-reacts with the immunoassay.
Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)
Not Found
Predicate Device(s): If the device was cleared using the 510(k) pathway, identify the Predicate Device(s) K/DEN number used to claim substantial equivalence and list them here in a comma separated list exactly as they appear in the text. List the primary predicate first in the list.
Reference Device(s): Identify the Reference Device(s) K/DEN number and list them here in a comma separated list exactly as they appear in the text.
Not Found
Predetermined Change Control Plan (PCCP) - All Relevant Information for the subject device only (e.g. presence / absence, what scope was granted / cleared under the PCCP, any restrictions, etc).
Not Found
§ 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).
0
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"
1
(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
2
and Toxicology Devices OHT7: Office of In Vitro Diagnostics Office of Product Evaluation and Quality Center for Devices and Radiological Health
Enclosure
3
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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4
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 Corporation
Thermo Fisher Scientific
46500 Kato Road
Fremont, CA 94538
Phone: 510-979-5000
Fax: 510-979-5002 |
|----------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Correspondent Contact
Information: | Pranjali Shinde
Microgenics Corporation
Thermo Fisher Scientific
46500 Kato Road
Fremont, CA-94538
Email: Pranjali.Shinde@Thermofisher.com
Phone: 510-979-5000
Fax: 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 Product
Code, Classification,
Classification Name & Panel | LFH, Class II,
21 CFR 862. 3910 - Tricyclic antidepressant drugs
test 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 test | |
| system, 91 – Toxicology |
B. Date Summary Prepared
November 17, 2023
5
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.
6
E. Comparison to Predicate Device
| Characteristics | Candidate Device:
Alinity c Tricyclic Antidepressants
Reagent Kit | Predicate Device:
DRI Tricyclics Serum Tox Assay
(K213875) |
|-----------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Intended Use | 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 DRI ™ Tricyclics Serum Tox
Assay is a homogeneous enzyme
immunoassay intended for the
qualitative and/or semiquantitative
determination of the presence of
tricyclic antidepressants (TCAs) in
human serum, plasma, or urine of
patients at a cutoff concentration
of 300 ng/mL in patients
suspected of drug overdose.
The semi-quantitative mode is for
the purpose of enabling
laboratories to determine an
appropriate dilution of the
specimen for confirmation by a
confirmatory method such as
Liquid Chromatography/Tandem
Mass Spectrometry (LC-MS/MS)
or permitting laboratories to
establish quality 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. |
7
| Operating
Principle
| (Technology) | DRI | Same |
|---|---|---|
| Measured Analyte | Nortriptyline | Same |
| Test Matrix | Serum, Plasma | Serum, Plasma, Urine |
| Cut-off Levels | 300 ng/mL | Same |
| Methodology | Homogeneous Enzyme | |
| Immunoassay | 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 Levels | ||
| for 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.
8
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.
| Spiked
Concentration
(ng/mL) | % of
Cutoff | Total Precision (n=80)
for 300 ng/mL cutoff – Serum | | |
|------------------------------------|----------------|--------------------------------------------------------|--------------------------------------------------------------|--------------------------------------------------------------------|
| | | # of
Determinants | Qualitative
Immunoassay
Results
(Negative/Positive) | Semi-Quantitative
Immunoassay
Results
(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.
9
| | % of
Cutoff | # of
Determinants | Total Precision (n=75) – Serum | |
|------------------------------------|----------------|----------------------|--------------------------------------------------------------|--------------------------------------------------------------------|
| Spiked
Concentration
(ng/mL) | | | Qualitative
Immunoassay
Results
(Negative/Positive) | Semi-quantitative
Immunoassay
Results
(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 |
10
| 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 to
C/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 | Expected
concentration
(ng/mL) | Average of observed
concentration (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
11
- 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 | |||||
|---|---|---|---|---|---|
| Alinity | |||||
| TCA | |||||
| Assay | |||||
| Results | Negative | ||||
| by LC- | |||||
| MS/MS | 450 | ||||
| ng/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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| Alinity
TCA
Assay
Results | Negative
by LC-
MS/MS | 450
ng/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-Quantitative
Observed 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 Related | |||
| Compounds | Tested | ||
| Concentration | |||
| (ng/mL) | Positive/Negative | Cross | |
| Reactivity (%) | |||
| 2-Hydroxy imipramine | 1300 | Positive | 23.1% |
| 7-Hydroxy quetiapine | 100000 | Negative |