(237 days)
No
The device description and performance studies detail a standard immunoassay technology and statistical analysis, with no mention of AI or ML algorithms.
No
This device is an in vitro diagnostic assay used for monitoring drug levels to help guide therapy, not for directly treating a condition.
Yes
The device's intended use is for the quantitative determination of Oxcarbazepine Metabolite in human serum to monitor drug levels and help ensure appropriate therapy, which is a diagnostic purpose.
No
The device description clearly outlines physical reagents (R1 and R2) and calibrators/controls, indicating it is a hardware-based immunoassay kit, not software only.
Yes, this device is an IVD (In Vitro Diagnostic).
Here's why:
- Intended Use: The intended use explicitly states it's for the "quantitative determination of Oxcarbazepine Metabolite in human serum on automated clinical chemistry analyzers." This involves testing a sample taken from the human body (in vitro) to provide information about a medical condition or state.
- Device Description: The description details a "homogeneous enzyme immunoassay" that uses reagents to measure a substance in a human specimen (serum). This is a common type of IVD technology.
- Regulatory Language: The statement "For prescription use only. Caution: Federal Law restricts this device to sale by or on the order of a licensed practitioner" is typical language for a medical device, and specifically for IVDs that are used in a clinical setting.
- Performance Studies: The document describes various performance studies (Limit of Quantitation, Recovery, Linearity, Method Comparison, Precision, Interfering Substances, Specificity, Drug Interference, Sample Stability, Calibration Curve Stability) which are standard evaluations for IVD devices to demonstrate their analytical performance.
- Intended User/Care Setting: "Routine clinical laboratory" is the typical setting where IVD tests are performed.
All these elements strongly indicate that the ARK™ Oxcarbazepine Metabolite Assay is an In Vitro Diagnostic device.
N/A
Intended Use / Indications for Use
The ARKIM Oxcarbazepine Metabolite Assay is a homogeneous enzyme immunoassay intended for the quantitative determination of Oxcarbazepine Metabolite in human serum on automated clinical chemistry analyzers. The measurements obtained are used in monitoring levels of Oxcarbazepine Metabolite to help ensure appropriate therapy.
The ARKIM Oxcarbazepine Metabolite Calibrator is intended for use in calibration of the ARK Oxcarbazepine Metabolite Assay.
The ARKIM Oxcarbazepine Metabolite Control is an assayed quality control material intended for use in quality control of the ARK Oxcarbazepine Metabolite Assay.
For prescription use only. Caution: Federal Law restricts this device to sale by or on the order of a licensed practitioner.
Product codes (comma separated list FDA assigned to the subject device)
POX, DLJ, LAS
Device Description
The ARK Oxcarbazepine Metabolite Assay is a homogeneous immunoassay based on competition between drug in the specimen and Oxcarbazepine Metabolite labeled with the enzyme glucose-6-phosphate dehydrogenase (G6PDH) for binding to the antibody reagent. As the latter binds antibody, enzyme activity decreases. In the presence of drug from the specimen, enzyme activity increases and is directly proportional to the drug concentration. Active enzyme converts the coenzyme nicotinamide adenine dinucleotide (NAD) to NADH that is measured spectrophotometrically as a rate of change in absorbance. Endogenous serum G6PDH does not interfere with the results because the coenyzme NAD functions only with the bacterial enzyme used in the assay.
The ARK Oxcarbazepine Metabolite Assay consists of reagents R1 anti-Oxcarbazepine Metabolite polyclonal antibody with substrate and R2 Oxcarbazepine Metabolite labeled with bacterial G6PDH enzyme. The ARK Oxcarbazepine Metabolite Calibrator consists of a six-level set to calibrate the assay, and the ARK Oxcarbazepine Metabolite Control consists of a three-level set used for quality control of the assay.
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
Routine clinical laboratory
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)
- Limit of Quantitation (LOQ): The LOQ was determined to be 1.0 ug/mL, defined as the lowest concentration for which acceptable inter-assay precision and recovery is observed (≤20% CV with ±15% recovery).
- Recovery: Analytical recovery was assessed by adding concentrated Oxcarbazepine Metabolite into human serum negative for Oxcarbazepine Metabolite across various enantiomer ratios. Mean recovered concentrations for theoretical concentrations from 1.0 to 45.0 ug/mL were reported.
- Linearity: Studies were performed as suggested in CLSI/NCCLS Protocol EP6-A. A linear relationship was demonstrated between 1.0 and 50.0 ug/mL (y = 1.0388x -0.0693).
- Assay Range: The measurement range is 1.0 to 37.0 ug/mL.
- Method Comparison: Correlation studies were performed using CLSI Protocol EP9-A3, comparing results with LC-MS/MS. Number of Samples: 190. Slope: 1.01 (0.98 to 1.04). y-intercept: -0.38 (-0.84 to 0.12). Correlation Coefficient (r^2): 0.95 (0.94 to 0.97).
- Precision: Determined as described in CLSI Protocol EP5-A3. Tri-level controls and three human serum pooled specimens were assayed in quadruplicate twice a day for 20 days (N=160 for each). Acceptance criterion: ≤10% CV. All reported CV% values were within this limit for ARK Control (LOW: 5.7%, MID: 4.8%, HIGH: 5.1%) and Human Serum (LOW: 5.5%, MID: 5.5%, HIGH: 5.1%).
- Interfering Substances: Interference studies conducted using CLSI Protocol EP7-A2. Measurement of Oxcarbazepine Metabolite resulted in ≤10% error in the presence of various interfering substances at the levels tested.
- Specificity: Cross-reactivity of MHD-Glucuronide, Dihydroxy-carbamazepine (DHD), Oxcarbazepine, Eslicarbazepine acetate, Carbamazepine, Dihydro – Carbamazepine, and Carbamazepine-epoxide was evaluated. MHD-Glucuronide and DHD levels are not crossreactive. The parent drugs oxcarbazepine and Eslicarbazepine Acetate crossreacted 22.2% and 22.1% respectively. Carbamazepine and its metabolites also showed cross-reactivity.
- Drug Interference: Other anti-epileptic or coadministered drugs tested did not crossreact with Oxcarbazepine Metabolite-selective antibody, with measurements resulting in
§ 862.3645 Neuroleptic drugs radioreceptor assay test system.
(a)
Identification. A neuroleptic drugs radioceptor assay test system is a device intended to measure in serum or plasma the dopamine receptor blocking activity of neuroleptic drugs and their active metabolites. A neuroleptic drug has anti-psychotic action affecting principally psychomotor activity, is generally without hypnotic effects, and is a tranquilizer. Measurements obtained by this device are used to aid in determining whether a patient is taking the prescribed dosage level of such drugs.(b)
Classification. Class II.
0
Image /page/0/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular seal with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged around the perimeter. Inside the circle is a stylized image of three human profiles facing to the right, with flowing lines representing hair or clothing.
Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002
August 9, 2016
ARK DIAGNOSTICS, INC. KENNETH KASPER EXECUTIVE DIRECTOR, QUALITY AND REGULATORY AFFAIRS 48089 FREMONT BLVD. FREMONT CA 94538
Re: K153596
Trade/Device Name: Ark Oxcarbazepine Metabolite Assay, Ark Oxcarbazepine Metabolite Calibrator, Ark Oxcarbazepine Metabolite Control Regulation Number: 21 CFR 862.3645 Regulation Name: Neuroleptic drugs radioreceptor assay test system Regulatory Class: II Product Code: POX, DLJ, LAS Dated: July 6, 2016 Received: July 8, 2016
Dear Kenneth Kasper:
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 (QS) regulation (21 CFR Part 820); and if applicable, the
1
electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
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/Resourcesfor You/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,
Courtney H. Lias -S
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
2
Indications for Use
510(k) Number (if known) K153596
Device Name ARKTM Oxcarbazepine Metabolite Assay ARK™M Oxcarbazepine Metabolite Calibrator ARK™ Oxcarbazepine Metabolite Control
Indications for Use (Describe)
The ARK™ Oxcarbazepine Metabolite Assay is a homogeneous enzyme immunoassay intended for the quantitative determination of Oxcarbazepine Metabolite in human serum on automated clinical chemistry analyzers. The measurements obtained are used in monitoring levels of Oxcarbazeoine Metabolite to help ensure appropriate therapy.
The ARK™ Oxcarbazepine Metabolite Calibration of the ARK Oxcarbazepine Metabolite Assay.
The ARK™ Oxcarbazepine Metabolite Control is an assayed quality control material intended for use in quality control of the ARK Oxcarbazepine Metabolite Assay.
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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3
510(k) SUMMARY
This summary of 510(k) safety and effectiveness information is being submitted in accordance with the requirements of SMDA 1990 and 21 CFR 807.92.
The assigned 510(k) number is K153596.
| 807.92 (a)(1): Name: | ARK Diagnostics, Inc. |
|---|---|
| Address: | 48089 Fremont Blvd |
| Fremont, CA 94538 | |
| Owner Operator Number: | 10027663 |
| Establishment Registration: | 3005755244 |
| Phone: | (510) 270-6270 |
| FAX: | (510) 270-6298 |
| Contact: | Kenneth C. Kasper, PhD – (510) 270-6280 |
| Executive Director of Quality and Regulatory Affairs |
Date prepared: August 9, 2016
807.92 (a)(2): Device name- trade name and common name, and classification
| Trade name: | ARK™ Oxcarbazepine Metabolite Assay
ARK™ Oxcarbazepine Metabolite Calibrator
ARK™ Oxcarbazepine Metabolite Control |
|-----------------|------------------------------------------------------------------------------------------------------------------------------|
| Common Name: | Homogeneous Enzyme Immunoassay |
| Classification: | 21 CFR 862.3645 POX Neuroleptic drugs radioreceptor assay test
system; Class II; 21 CFR 862.3200 DLJ; 21 CFR 862.3280 LAS |
807.92 (a)(3): Identification of the legally marketed predicate device
| Emit® 2000 Carbamazepine Assay | K010814 |
|---|---|
| ARK™ Topiramate Calibrator | K083799 |
| ARK™ Topiramate Control | K083799 |
4
807.92 (a)(4): Device Description
The ARK Oxcarbazepine Metabolite Assay is a homogeneous immunoassay based on competition between drug in the specimen and Oxcarbazepine Metabolite labeled with the enzyme glucose-6-phosphate dehydrogenase (G6PDH) for binding to the antibody reagent. As the latter binds antibody, enzyme activity decreases. In the presence of drug from the specimen, enzyme activity increases and is directly proportional to the drug concentration. Active enzyme converts the coenzyme nicotinamide adenine dinucleotide (NAD) to NADH that is measured spectrophotometrically as a rate of change in absorbance. Endogenous serum G6PDH does not interfere with the results because the coenyzme NAD functions only with the bacterial enzyme used in the assay.
The ARK Oxcarbazepine Metabolite Assay consists of reagents R1 anti-Oxcarbazepine Metabolite polyclonal antibody with substrate and R2 Oxcarbazepine Metabolite labeled with bacterial G6PDH enzyme. The ARK Oxcarbazepine Metabolite Calibrator consists of a six-level set to calibrate the assay, and the ARK Oxcarbazepine Metabolite Control consists of a threelevel set used for quality control of the assay.
807.92 (a)(5): Intended Use / Indications for Use
The ARKIM Oxcarbazepine Metabolite Assay is a homogeneous enzyme immunoassay intended for the quantitative determination of Oxcarbazepine Metabolite in human serum on automated clinical chemistry analyzers. The measurements obtained are used in monitoring levels of Oxcarbazepine Metabolite to help ensure appropriate therapy.
The ARKIM Oxcarbazepine Metabolite Calibrator is intended for use in calibration of the ARK Oxcarbazepine Metabolite Assay.
The ARKIM Oxcarbazepine Metabolite Control is an assayed quality control material intended for use in quality control of the ARK Oxcarbazepine Metabolite Assay.
For prescription use only. Caution: Federal Law restricts this device to sale by or on the order of a licensed practitioner.
Summary and Explanation
Oxcarbazepine [10, 11-dihydro-10-oxo-5H-dibenzo[b,f]azepine-5-carboxamide] and eslicarbazapine [{{}-10-acetoxy-10,11-dihydro-5H-dibenz|b,f|azepine- 5-carboxamide] are prodrugs that are metabolized to an active metabolite (10,11-dihydro-10-hydroxy-5Hdibenz[b.flazepine-5-carboxamide). Oxcarbazepine Metabolite is often called 10-monohydroxy derivative (MHD) or referred to as licarbazepine (Trileptal, Novartis) is metabolized to two enantiomers (S)-MHD and (R)-MHD at a metabolite ratio of approximately 4:1, respectively.
Eslicarbazepine acetate (Antion Pharmaceuticals) is prescribed as adjunctive therapy for partial-onset seizures associated with epilepsy in adults. Eslicarbazepine acetate is [(S)-10-Acetoxy-10,11-dihydro-5Hdibenz[b,f]azepine-5-carboxamide] and metabolism to (S)-MHD is favored such that the metabolite ratio of (S)-MHD to (R)-MHD is approximately 19:1.
5
ARK Oxcarbazepine Metabolite Calibrator
The ARK Oxcarbazepine Metabolite Calibrator is traceable to certified Oxcarbazepine Metabolite powder. The purity of Oxcarbazepine Metabolite in the certified raw material is determined by NMR and elemental analysis as performed by the supplier of the certified powder.
Bulk solutions of the ARK Oxcarbazepine Metabolite Calibrator are prepared volumetrically using a stock solution prepared by gravimetric addition of powder to solvent. The concentration of Oxcarbazepine Metabolite in the respective bulk solution must agree within 5% of its corresponding master calibrator.
Value Assignment: Testing is performed with the ARK Oxcarbazepine Metabolite Assay on the Beckman Coulter AU480® automated analyzer. Two calibrated runs are performed using the Master Calibrator. In each run, five replicates of Master Lot (reference) and Test Lot are tested as matched pairs for each calibrator level. Mean values for ten replicates are calculated. Test lot mean values are expected to match the Master lot mean values within 5% allowance.
| REF | Product Description | Quantity/Volume |
|---|---|---|
| 5032-0002-00 | ARK Oxcarbazepine Metabolite Calibrators* | Dropper vials |
| Oxcarbazepine Metabolite, buffer, bovine | ||
| serum albumin, and sodium azide | ||
| A | ||
| 0.0 µg/mL | 1 X 4 mL | |
| B | ||
| 2.0 µg/mL | 1 X 2 mL | |
| C | ||
| 5.0 µg/mL | 1 X 2 mL | |
| D | ||
| 12.0 µg/mL | 1 X 2 mL | |
| E | ||
| 25.0 µg/mL | 1 X 2 mL | |
| F | ||
| 50.0 µg/mL | 1 X 2 mL |
*To convert results from µg/mL Oxcarbazepine Metabolite, multiply µg/mL by 3.933. Oxcarbazepine Metabolite levels become 7.9, 19.7, 47.2, 98.3, and 196.6 µmol/L for Calibrators B to F respectively.
6
ARK Oxcarbazepine Metabolite Control
The ARK Oxcarbazepine Metabolite Control is traceable to certified Oxcarbazepine Metabolite powder. The purity of Oxcarbazepine Metabolite in the certified raw material is determined by NMR and elemental analysis as performed by the supplier of the certified powder.
Bulk solutions of the ARK Oxcarbazepine Metabolite Control are prepared volumetrically using a stock solution prepared by gravimetric addition of powder to solvent. ARK manufactures the controls to contain Oxcarbazepine Metabolite within 10% of the target levels.
Value Assignment: Testing is performed with the ARK Oxcarbazepine Metabolite Assay on the Beckman Coulter AU480® automated analyzer, calibrated with the master calibrator lot. Three calibrated runs are performed using four replicates of each level per run. The expected control ranges are set according to mean values. Each laboratory should establish the mean value for each control level and its own ranges for each new lot of controls.
| REF | Product Description | Quality Control |
|---|---|---|
| 5032-0003-00 | ARK Oxcarbazepine Metabolite Control* (4 mL) | Expected Range |
| Oxcarbazepine Metabolite, buffer, bovine serum | ||
| albumin, and sodium azide (target level) | (Mean µg/mL) | |
| LOW (3.0 µg/mL) | 2.4 – 3.6 | |
| MID (10.0 µg/mL) | 8.5 – 11.5 | |
| HIGH (30.0 µg/mL) | 25.0 – 35.0 |
*To convert results from ug/mL Oxcarbazepine Metabolite, multiply µg/mL by 3.933. Oxcarbazepine Metabolite levels become 11.8, 39.3 and 118.0 µmol/L for LOW, MID and HIGH respectively.
7
807.92 (a)(6): Technological Similarities and Differences to the Predicate
SUBSTANTIAL EQUIVALENCE COMPARATIVE CHART
| Characteristic | Device | Predicate |
|---|---|---|
| ARKTM Oxcarbazepine Metabolite Assay | Emit® 2000 Carbamazepine Assay K010814 | |
| Intended Use | The ARKTM Oxcarbazepine | |
| Metabolite | ||
| Assay is intended for the quantitative | ||
| determination of Oxcarbazepine Metabolite | ||
| in human serum on automated clinical | ||
| chemistry analyzers. | The Emit® 2000 Carbamazepine Assay is a | |
| homogeneous enzyme immunoassay | ||
| intended for use in the quantitative analysis | ||
| of carbamazepine in human serum or plasma. | ||
| Indications for Use | The measurements obtained are used in | |
| monitoring levels | ||
| of Oxcarbazepine | ||
| Metabolite | ||
| to help ensure appropriate | ||
| therapy. | The results obtained helps physicians | |
| individualize dosage regimens. | ||
| Sample | Serum | Serum or plasma |
| Methodology | Homogenous enzyme immunoassay (EIA) | Homogenous enzyme immunoassay (EIA) |
| Reagent | ||
| Components | Two (2) reagent system: | |
| Anti- Oxcarbazepine Metabolite | ||
| Antibody/Substrate Reagent (R1) containing | ||
| rabbit polyclonal antibodies to | ||
| Oxcarbazepine Metabolite, glucose-6- | ||
| phosphate, nicotinamide adenine | ||
| dinucleotide, bovine serum albumin, sodium | ||
| azide, and stabilizers |
Enzyme Reagent (R2) containing
Oxcarbazepine Metabolite labeled with
bacterial G6PDH, buffer, bovine serum
albumin, sodium azide, and stabilizers | Two (2) reagent system:
Antibody/Substrate Reagent (R1) containing
mouse monoclonal antibodies to
carbamazepine, glucose-6-phosphate,
nicotinamide adenine dinucleotide.
Enzyme Reagent (R2) containing
carbamazepine labeled with bacterial
G6PDH, buffer.
Sodium azide, buffer, preservatives, and
stabilizers |
| Platform required | Automated clinical chemistry analyzer | Automated clinical chemistry analyzer |
| Testing
environment | Routine clinical laboratory | Routine clinical laboratory |
| Reagent condition
and storage | Liquid, 2-8° C | Liquid, 2-8° C |
8
| Calibrators: Similarities and Differences | ||
|---|---|---|
| Item | Candidate Device (ARK | |
| Oxcarbazepine | ||
| Calibrator) | Predicate Device (ARK | |
| Topiramate Calibrator; | ||
| K083799) | ||
| Intended Use/Indications | ||
| for Use | ARK Oxcarbazepine | |
| Metabolite Calibrator is | ||
| intended for use in | ||
| calibration of the ARK | ||
| Oxcarbazepine Metabolite | ||
| Assay. | The ARK Topiramate | |
| Calibrator is intended for | ||
| use in calibration of the | ||
| ARK Topiramate Assay. | ||
| Matrix | Synthetic protein matrix | |
| (buffer, bovine serum | ||
| albumin, preservatives) | Same | |
| Levels | 6 | Same |
| Controls: Similarities and Differences | ||
|---|---|---|
| Item | Candidate Device (ARK Oxcarbazepine Control) | Predicate Device (ARK Topiramate Control; K083799) |
| Intended Use/Indications for Use | The ARK Oxcarbazepine Metabolite Control is an assayed quality control material intended for use in quality control of the ARK Oxcarbazepine Metabolite Assay. | The ARK Topiramate Control is intended for use in quality control of the ARK Topiramate Assay. |
| Matrix | Synthetic protein matrix (buffer, bovine serum albumin, preservatives) | Same |
| Levels | 3 (LOW, MID, HIGH) | Same |
9
807.92 (b)(1) and 807.92 (b)(2): Brief Description of Nonclinical and Clinical Data
The following performance characteristics were obtained on the Beckman Coulter AU480® automated clinical chemistry analyzer. Unless otherwise stated, a metabolite S:R ratio of 9:1 was used to evaluate performance.
Limit of Quantitation (LOQ)
The LOQ of the ARK Oxcarbazepine Metabolite Assay was determined according to CLSI EP17-A2 and is defined as the lowest concentration for which acceptable inter-assay precision and recovery is observed (≤20% CV with ±15% recovery). The LOQ was determined to be 1.0 ug/mL, and may depend on analyzer-specific performance.
Recovery
Analytical recovery throughout the measurement range was assessed by adding concentrated Oxcarbazepine Metabolite into human serum negative for Oxcarbazepine Metabolite. The S:R ratio of each enantiomer was varied. The mean of six (6) replicate measurements of Oxcarbazepine Metabolite was tabulated as a function of the enantiomer ratio.
| Mean Recovered Concentration (µg/mL) | ||||
|---|---|---|---|---|
| Theoretical | ||||
| Concentration | ||||
| (µg/mL) | S:R | |||
| 1:1 | S:R | |||
| 4:1 | S:R | |||
| 9:1 | S:R | |||
| 19:1 | ||||
| 1.0 | 0.77 | 0.93 | 0.98 | 0.95 |
| 4.0 | 3.78 | 3.92 | 3.94 | 3.86 |
| 8.0 | 7.47 | 8.18 | 8.16 | 7.82 |
| 15.0 | 14.10 | 15.80 | 14.91 | 15.42 |
| 20.0 | 19.03 | 21.69 | 19.81 | 21.02 |
| 35.0 | 33.74 | 34.71 | 33.52 | 36.16 |
| 45.0 | 42.89 | 46.88 | 44.63 | 49.46 |
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Linearity
Linearity studies were performed as suggested in CLSI/NCCLS Protocol EP6-A. A 60.0 µg/mL serum sample was prepared and dilutions were made proportionally with human serum negative for Oxcarbazepine Metabolite. Oxcarbazepine Metabolite concentrations ranged from 1.0 to 50.0 ug/mL. Linearity at specific dilutions was considered acceptable if the percent difference was ±10% between the predicted 1st and 200 order regressed values or ≤ 0.20 µg/mL below 2.0 ug/mL. A linear relationship was demonstrated between 1.0 and 50.0 ug/mL (y = 1.0388x -0.0693). Results are shown below.
| Estimated
Value
(µg/mL) | Results
(µg/mL) | 1st Order
Predicted
Results | 2nd Order
Predicted
Results | Difference |
|-------------------------------|--------------------|-----------------------------------|-----------------------------------|------------|
| 1.00 | 1.00 | 0.97 | 1.11 | 0.14 µg/mL |
| 3.00 | 3.19 | 3.05 | 3.11 | 2.2 % |
| 5.00 | 5.14 | 5.12 | 5.12 | 0.0 % |
| 10.00 | 10.26 | 10.32 | 10.18 | -1.3 % |
| 20.00 | 21.01 | 20.71 | 20.41 | -1.4 % |
| 30.00 | 29.88 | 31.09 | 30.80 | -0.9 % |
| 40.00 | 41.92 | 41.48 | 41.36 | -0.3 % |
| 50.00 | 52.13 | 51.87 | 52.07 | 0.4 % |
Assay Range
The measurement range of the ARK Oxcarbazepine Metabolite Assay is 1.0 to 37.0 ug/mL based on clinical concentrations tested. Report results below this range as 37.0 ug/mL or test a diluted specimen having a concentration within the measurement range.
Specimens testing initially above the measurement range may be diluted in Calibrator A and retested. Multiply the assay result by the dilution factor to obtain the concentration of Oxcarbazepine Metabolite in the undiluted specimen.
11
Method Comparison
Correlation studies were performed using CLSI Protocol EP9-A3. Results from the ARK Oxcarbazepine Metabolite Assay were compared with results from LC-MS/MS. The Oxcarbazepine Metabolite concentrations ranged from 1.7 µg/mL to 36.4 µg/mL. Results of the Passing-Bablok regression analysis for the study are shown below (with 95% confidence limits).
| Slope | 1.01 | (0.98 to 1.04) |
|---|---|---|
| y-intercept | -0.38 | (-0.84 to 0.12) |
| Correlation Coefficient ( $r^2$ ) | 0.95 | (0.94 to 0.97) |
| Number of Samples | 190 |
Image /page/11/Figure/3 description: This image is a scatter plot that compares two different methods of measuring Oxcarbazepine Metabolite. The x-axis represents the LC-MS/MS method in ug/mL, while the y-axis represents the ARK Oxcarbazepine Metabolite Assay method in ug/mL. The data points are clustered around a blue line, indicating a positive correlation between the two methods. The values on both axes range from 0.0 to 40.0 ug/mL.
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Precision
Precision was determined as described in CLSI Protocol EP5-A3. Tri-level controls and three human serum pooled specimens containing Oxcarbazepine Metabolite were used in the study. Each level was assayed in quadruplicate twice a day for 20 days. Each of the runs per day was separated by at least two hours. The within-run, between-day, total SD, and percent CVs were calculated. Acceptance criterion: ≤10% CV.
| Within Run | Between Day | Total | ||||||
|---|---|---|---|---|---|---|---|---|
| Sample | N | Mean | ||||||
| (µg/mL) | SD | CV | ||||||
| (%) | SD | CV (%) | SD | CV (%) | ||||
| ARK Control | ||||||||
| LOW | 160 | 3.0 | 0.12 | 4.0 | 0.12 | 4.1 | 0.17 | 5.7 |
| MID | 160 | 10.1 | 0.37 | 3.6 | 0.33 | 3.2 | 0.48 | 4.8 |
| HIGH | 160 | 30.2 | 0.99 | 3.3 | 1.19 | 3.9 | 1.54 | 5.1 |
| Human Serum | ||||||||
| LOW | 160 | 3.1 | 0.12 | 3.9 | 0.12 | 4.0 | 0.17 | 5.5 |
| MID | 160 | 10.1 | 0.38 | 3.8 | 0.36 | 3.6 | 0.55 | 5.5 |
| HIGH | 160 | 30.4 | 1.10 | 3.6 | 1.11 | 3.7 | 1.55 | 5.1 |
Interfering Substances
Interference studies were conducted using CLSI Protocol EP7-A2 as a guideline. Clinically high concentrations of the following potentially interfering substances in serum with known levels of Oxcarbazepine Metabolite (approximately 3 and 30 µg/mL) were evaluated. Each sample was assayed using the ARK Oxcarbazepine Metabolite Assay, along with a serum control of Oxcarbazepine Metabolite. Measurement of Oxcarbazepine Metabolite resulted in ≤10% error in the presence of interfering substances at the levels tested.
| Percentage Recovery | |||
|---|---|---|---|
| Interfering | |||
| Substance | Interferent | ||
| Concentration | 3 µg/mL | ||
| Oxcarbazepine | |||
| Metabolite | 30 µg/mL | ||
| Oxcarbazepine | |||
| Metabolite | |||
| Human Albumin | 12 g/dL | 102.2 | 95.1 |
| Bilirubin - conjugated | 70 mg/dL | 108.6 | 100.2 |
| Bilirubin - unconjugated | 70 mg/dL | 102.7 | 92.4 |
| Cholesterol | 602 mg/dL | 96.5 | 103.5 |
| Human IgG | 12 g/dL | 93.1 | 93.1 |
| Hemoglobin | 1000 mg/dL | 105.7 | 100.7 |
| Rheumatoid Factor | 1000 IU/mL | 101.0 | 103.9 |
| Triglycerides | 1000 mg/dL | 96.6 | 94.3 |
| Uric Acid | 30 mg/dL | 107.5 | 95.5 |
13
Specificity
MHD-Glucuronide and Dihydroxy-carbamazepine (synonymous with dihydroxy-derivative of oxcarbazepine or DHD) are secondary metabolites of Oxcarbazepine Metabolite (MHD). Oxcarbazepine and Eslicarbazepine acetate are parent drugs for MHD. Carbamazepine and its metabolites (Dihydrocarbamazepine and Carbamazepine-epoxide) are compounds structurally similar to MHD. All were tested for crossreactivity at the concentrations listed in the presence of MHD (20 ug/mL) in serum. MHD-Glucuronide levels may appear in serum greater than MHD in cases of renal impairment". MHD-Glucuronide and DHD levels are not crossreactive.
The parent drug oxcarbazepine crossreacted 22.2% (as did Eslicarbazepine Acetate), although neither Oxcarbazepine nor Eslicarbazepine Acetate are expected to be present with MHD at a significant level due to rapid renal clearance. Carbamazepine and its metabolites also crossreacted in the assay; the possibility of co-therapy or transition of therapy should be considered.
| Metabolite | Level Tested
(µg/mL) | Percent Cross-
Reactivity | Percent
Interference |
|----------------------------------------------|-------------------------|------------------------------|-------------------------|
| MHD Glucuronide | 20 | 1.6 | 1.6 |
| MHD Glucuronide | 40 | 0.0 | -0.1 |
| MHD Glucuronide | 100 | 1.5 | 7.4 |
| MHD Glucuronide | 200 | 1.0 | 10.5 |
| (DHD) Dihydro-
dihydroxy
carbamazepine | 5.0 | -11.3 | -2.9 |
| Oxcarbazepine | 20.0 | 22.2 | 22.6 |
| Eslicarbazepine
acetate | 20.0 | 22.1 | 22.4 |
| Carbamazepine | 20.0 | 20.4 | 20.7 |
| Dihydro –
Carbamazepine | 5.0 | 6.0 | 1.5 |
| Carbamazepine-
epoxide | 10.0 | 13.6 | 6.9 |
Drug Interference
Other anti-epileptic or coadministered drugs tested did not crossreact with Oxcarbazepine Metabolite-selective antibody. A high concentration of each compound was spiked into normal human serum with known levels of Oxcarbazepine Metabolite (approximately 3 and 30 ug/mL) and assayed along with a serum control of Oxcarbazepine Metabolite. Measurement of Oxcarbazepine Metabolite resulted in