(55 days)
The DRI Benzodiazepine Assay is a homogeneous enzyme immunoassay intended for the qualitative and/or semi-quantitative determination of the presence of benzodiazepines and their metabolites in human urine at a cutoff concentration of 200 ng/mL. The assay is intended to be used in laboratories a simple and rapid analytical screening procedure to detect benzodiazepines in human urine. The assay is designed for use with a number of clinical chemistry analyzers. This assay is calibrated against Oxazepam. This product is intended to be used by trained professionals only.
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 must be used to obtain a confirmed analytical result. Gas chromatography/ mass spectrometry (GC/MS) or 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 results are used. For In Vitro Diagnostic Use Only.
The DRI Benzodiazepine Assay is a homogeneous enzyme immunoassay with liquid ready-to-use reagents. The assay uses a specific antibody which can detect most benzodiazepines and their metabolites in urine. The assay is based on the competition of an enzyme glucose- 6-phosphate dehydrogenase (G6PDH) labeled drug and the drug from the urine sample for a fixed amount of specific antibody binding sites. In the absence of free drug from the sample, the enzyme-labeled drug is bound by the specific antibody and the enzyme activity is inhibited. This phenomenon creates a relationship between drug concentration in urine and the enzyme activity. The enzyme G6PDH activity is determined spectrophotometrically at 340 nm by measuring its ability to convert nicotinamide adenine dinucleotide (NAD) to NADH.
The assay consists of reagents A and E.
Reagent A: Contains sheep polyclonal anti-benzodiazepine antibodies, glucose-6-phosphate (G6P) and nicotinamide adenine dinucleotide (NAD) in Tris buffer with sodium azide as a preservative.
Reagent E: Contains benzodiazepine derivative labeled with glucose-6-phosphate dehydrogenase (G6PDH) in Tris buffer with sodium azide as a preservative.
The provided document describes the analytical performance verification of the DRI Benzodiazepine Assay, an in vitro diagnostic device, and not an AI/ML-enabled medical device. Therefore, many of the requested categories (e.g., number of experts, adjudication methods, MRMC studies, standalone performance of an algorithm, training set details) are not applicable to this type of device and study.
However, I can extract the acceptance criteria and reported performance for the analytical studies conducted, which demonstrate the device's substantial equivalence to a predicate device.
Device Name: DRI Benzodiazepine Assay
Regulation Number: 21 CFR 862.3170
Regulation Name: Benzodiazepine test system
Regulatory Class: Class II
Product Code: JXM
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state "acceptance criteria" in a tabulated format for each study, but rather presents the results of various analytical performance studies which are implicitly used to demonstrate the device's suitability and substantial equivalence. I will infer the acceptance criteria from typical requirements for such in vitro diagnostic assays and the presented results.
| Study Parameter | Implied Acceptance Criterion (Typical for IVD) | Reported Device Performance |
|---|---|---|
| Precision (Qualitative) | All replicates at ±25%, ±50%, ±75%, ±100% of cutoff show consistent classification; some variability expected at cutoff (200 ng/mL). | At -100% (0 ng/mL), -75% (50 ng/mL), -50% (100 ng/mL), -25% (150 ng/mL): 80/80 (100%) Negative. At +25% (250 ng/mL), +50% (300 ng/mL), +75% (350 ng/mL), +100% (400 ng/mL): 80/80 (100%) Positive. At 100% cutoff (200 ng/mL): 16/64 (20%/80%) Negative/Positive. |
| Precision (Semi-Quantitative) | Similar to qualitative, with expected distribution around cutoff. | At -100% (0 ng/mL), -75% (50 ng/mL), -50% (100 ng/mL), -25% (150 ng/mL): 80/80 (100%) Negative. At +25% (250 ng/mL), +50% (300 ng/mL), +75% (350 ng/mL), +100% (400 ng/mL): 80/80 (100%) Positive. At 100% cutoff (200 ng/mL): 27/53 (33.75%/66.25%) Negative/Positive. |
| Spike Recovery (Qualitative) | Accurate classification of samples below/above cutoff. | 150 ng/mL (Below Cutoff): 20/20 (100%) Negative. 250 ng/mL (Above Cutoff): 20/20 (100%) Positive. |
| Analytical Recovery and Linearity | Recoveries within a generally accepted range (e.g., 80-120%) across the tested range. Implies accuracy and proportionality to concentration. | Recovery between 98.1% and 113.8% for Oxazepam concentrations ranging from 100 ng/mL to 1000 ng/mL. (Level 1, 0 ng/mL, N/A recovery). |
| Method Comparison and Accuracy (Qualitative) | High overall agreement with confirmatory method (LC-MS/MS), particularly for positive and negative agreement. | Overall agreement with LC-MS/MS: 96.2% (102/106 samples). Negative agreement: 92.9% (52/56). Positive agreement: 100% (50/50). Four discordant samples identified as positive by the device but below cutoff by LC-MS/MS were due to significant levels of benzodiazepine metabolites not quantified by the parent compound concentration in LC-MS/MS, which the immunoassay cross-reacts with. This is expected behavior for an immunoassay designed to detect metabolites. |
| Method Comparison and Accuracy (Semi-Quantitative) | High overall agreement with confirmatory method (LC-MS/MS), similar to qualitative. | Overall agreement with LC-MS/MS: 96.2% (102/106 samples). Negative agreement: 92.9% (52/56). Positive agreement: 100% (50/50). Same four discordant samples as qualitative, explained by metabolite cross-reactivity. |
| Specificity (Cross-reactivity with structurally related compounds) | Detection of various benzodiazepine compounds and their metabolites at specified concentrations. | Many compounds showed excellent cross-reactivity (e.g., α-Hydroxyalprazolam, Alprazolam, Estazolam, Diazepam, Flunitrazepam, Nordiazepam, Oxazepam) with cross-reactivity >90% (e.g., 91-200%). Some showed lower but acceptable cross-reactivity (e.g., 7-Aminoclonazepam: 8%; Chlordiazepoxide: 29%; Lorazepam: 29%). Glucuronides conjugate forms typically show very low cross-reactivity (<0.4%). |
| Specificity (Interference from structurally unrelated compounds) | No significant interference with accurate classification of low and high controls. | All tested compounds (a wide range of common drugs and substances like Acetaminophen, Amphetamine, Caffeine, Codeine, Ibuprofen, Morphine, etc.) did not interfere with the accurate classification of the spiked low (Negative) and high (Positive) Oxazepam controls, even at high concentrations (e.g., 100,000 ng/mL to 1,000,000 ng/mL). |
| Interference (pH and Endogenous Substances) | No significant interference from tested pH levels or endogenous substances. | All tested pH levels (3.0-11.0) and endogenous substances (Acetone, Ascorbic acid, Creatinine, Ethanol, Glucose, Hemoglobin, etc.) at high concentrations did not interfere with the accurate classification of spiked low (Negative) and high (Positive) Oxazepam controls. |
| Specific Gravity | No significant interference from urine specific gravity variations. | All tested specific gravity values (1.004 to 1.029) did not interfere with the accurate classification of spiked low (Negative) and high (Positive) Oxazepam controls. |
2. Sample Size Used for the Test Set and Data Provenance
- Precision Studies: 80 replicates per concentration level (2 replicates, twice per day for 20 days). Samples were prepared by spiking Oxazepam into drug-free urine.
- Spike Recovery: 20 replicates for each spiked concentration (150 ng/mL and 250 ng/mL). Samples were prepared by spiking Oxazepam into drug-free urine.
- Analytical Recovery and Linearity: 10 intermediate dilution levels, each run in replicates of five. Samples were prepared by spiking Oxazepam into drug-free urine.
- Method Comparison and Accuracy: 106 patient samples.
- Data Provenance: The document states "One hundred and six patient samples were analyzed...". The country of origin is not explicitly stated, but the submission is to the U.S. FDA, and the company address is Fremont, CA, implying the studies were likely conducted in the US. The samples are referred to as "patient samples," which typically implies retrospective collection for assay validation, but it's not explicitly stated as retrospective or prospective.
- Specificity (Cross-reactivity & Interference): Samples were prepared by adding known amounts of compounds to drug-free negative urine, or spiking controls.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
- Not Applicable. This is an in vitro diagnostic assay, not an AI/ML-enabled image analysis device. The ground truth for chemical analytes (benzodiazepines) in urine samples is established by a reference analytical method, specifically Gas Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/tandem Mass Spectrometry (LC-MS/MS), which are considered the "gold standard" for drug confirmations in toxicology. No human experts (e.g., radiologists) were involved in establishing the ground truth.
4. Adjudication Method for the Test Set
- Not Applicable. As the ground truth is established by an objective chemical confirmatory method (LC-MS/MS), there is no need for human adjudication of results in the traditional sense seen in imaging studies. Discrepancies between the immunoassay and LC-MS/MS are analyzed scientifically to understand the reason (e.g., cross-reactivity with metabolites, which is precisely what the immunoassay is designed to do).
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
- Not Applicable. This is an in vitro diagnostic (IVD) assay, not an AI/ML diagnostic aid. It does not involve "human readers" in the context of image interpretation or clinical decision-making from an AI output. Its performance is evaluated analytically against a reference method.
6. If a Standalone (i.e. algorithm only without human-in-the loop performance) was done
- Not Applicable. This is an IVD assay. Its performance is inherently "standalone" in the sense that the device itself produces a result (qualitative or semi-quantitative) based on chemical reactions. There is no algorithm in the AI sense, nor a "human-in-the-loop" interaction directly with the assay's output similar to how one might interact with an AI-generated image finding. The results are interpreted by trained professionals.
7. The Type of Ground Truth Used
- Confirmatory Method / Gold Standard: The ground truth for benzodiazepine concentrations in urine samples was established using a "confirmatory method such as Liquid Chromatography/tandem Mass Spectrometry (LC-MS/MS)" (stated in the Indications for Use and the Method Comparison study). This is considered the preferred confirmatory method in toxicology.
8. The Sample Size for the Training Set
- Not Applicable. This is a traditional enzyme immunoassay, not a machine learning model. There is no "training set" in the context of AI/ML. The assay formulation (reagents, antibodies) is developed through biochemical research and optimization, not data-driven machine learning training.
9. How the Ground Truth for the Training Set was Established
- Not Applicable. (See #8). As there is no training set for an AI model, there is no ground truth to be established for it. The "ground truth" (i.e., known concentrations or presence/absence of analytes) for the samples used in analytical validation studies (e.g., linearity, accuracy, specificity) would be established using validated reference methods or precise spiking of known concentrations into a blank matrix.
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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.
February 21, 2018
MICROGENICS CORPORATION MINOTI PATEL MANAGER, REGULATORY AFFAIRS 46500 KATO ROAD FREMONT, CA 94538
Re: K173963
Trade/Device Name: DRI Benzodiazepine Assay Regulation Number: 21 CFR 862.3170 Regulation Name: Benzodiazepine test system Regulatory Class: Class II Product Code: JXM Dated: December 27, 2017 Received: December 28, 2017
Dear Minoti Patel:
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 Part 801 and Part 809); medical device 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
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Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.
For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/) and CDRH Learn (http://www.fda.gov/Training/CDRHLearn). 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 (http://www.fda.gov/DICE) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely,
Kellie B. Kelm -S
for Courtney H. Lias, Ph.D. Director Division of Chemistry and Toxicology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health
Enclosure
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Indications for Use
510(k) Number (if known) K173963
Device Name DRI Benzodiazepine Assay
Indications for Use (Describe)
The DRI Benzodiazepine Assay is a homogeneous enzyme immunoassay intended for the qualitative and/or semiquantitative determination of the presence of benzodiazepines and their metabolites in human urine at a cutoff concentration of 200 ng/mL. The assay is intended to be used in laboratories a simple and rapid analytical screening procedure to detect benzodiazepines in human urine. The assay is designed for use with a number of clinical chemistry analyzers. This assay is calibrated against Oxazepam. This product is intended to be used by trained professionals only.
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 must be used to obtain a confirmed analytical result. Gas chromatography/ mass spectrometry (GC/MS) or 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 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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K173963
510(k) Summary
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
| Category | Comments |
|---|---|
| Sponsor: | Microgenics CorporationThermo Fisher Scientific46500 Kato RoadFremont, CA 94538Phone: 510-979-5000FAX: 510-979-5002 |
| Correspondent ContactInformation: | Minoti Patel, RACManager, Regulatory AffairsEmail: Minoti.patel@thermofisher.comPhone: 510-979-5000FAX: 510-979-5002 |
| Device Common Name: | Benzodiazepine Enzyme Immunoassay |
| Trade or Proprietary Name | DRI Benzodiazepine Assay |
| Candidate Device ProductCode, Classification,Classification Name &Panel | JXM, Class II, 21 CFR 862.3170 – Benzodiazepine testsystem, 91 - Toxicology |
Predicate Device Information:
| Predicate Device: | Benzodiazepine Enzyme Immunoassay |
|---|---|
| Predicate DeviceManufacturer: | Diagnostic Reagents, Inc. |
| Predicate Device PremarketNotification #: | K930529 |
B. Date Summary Prepared
February 20, 2018
C. Description of Device
The DRI Benzodiazepine Assay is a homogeneous enzyme immunoassay with liquid ready-to-use reagents. The assay uses a specific antibody which can detect most benzodiazepines and their metabolites in urine. The assay is based on the competition of an enzyme glucose- 6-phosphate dehydrogenase (G6PDH) labeled drug and the drug from the urine sample for a fixed amount of specific antibody binding sites. In the absence of free drug from the sample, the enzyme-labeled drug is bound by the specific antibody and the enzyme activity is inhibited. This phenomenon
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creates a relationship between drug concentration in urine and the enzyme activity. The enzyme G6PDH activity is determined spectrophotometrically at 340 nm by measuring its ability to convert nicotinamide adenine dinucleotide (NAD) to NADH.
The assay consists of reagents A and E.
Reagent A: Contains sheep polyclonal anti-benzodiazepine antibodies, glucose-6-phosphate (G6P) and nicotinamide adenine dinucleotide (NAD) in Tris buffer with sodium azide as a preservative.
Reagent E: Contains benzodiazepine derivative labeled with glucose-6-phosphate dehydrogenase (G6PDH) in Tris buffer with sodium azide as a preservative.
D. Intended Use
DRI Benzodiazepine Assay:
The DRI Benzodiazepine Assay is a homogeneous enzyme immunoassay intended for the qualitative and/or semi-quantitative determination of the presence of benzodiazepines and their metabolites in human urine at a cutoff concentration of 200 ng/mL. The assay is intended to be used in laboratories and provides a rapid analytical screening procedure to detect benzodiazepines in human urine. The assay is designed for use with a number of clinical chemistry analyzers. This assay is calibrated against Oxazepam. This product is intended to be used by trained professionals only.
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. Gas chromatography/ mass spectrometry (GC/MS) or Liquid chromatography/tandem mass spectrometry (LC-MS/MS) is the preferred confirmatory method.1,2
Clinical and professional judgment should be applied to any drug of abuse test result, particularly when preliminary results are used. For In Vitro Diagnostic Use Only.
| Characteristic | Candidate Device:DRI Benzodiazepine Assay | Predicate Device:DRI Benzodiazepine Assay(K930529). |
|---|---|---|
| Intended Use | The DRI BenzodiazepineAssay is a homogeneousenzyme immunoassayintended for the qualitativeand/or semi-quantitativedetermination of the presence | Same |
E. Comparison to Predicate Device
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| Characteristic | Candidate Device:DRI Benzodiazepine Assayof benzodiazepines and theirmetabolites in human urine ata cutoff concentration of 200ng/mL. | Predicate Device:DRI Benzodiazepine Assay(K930529). |
|---|---|---|
| OperatingPrinciple(Technology) | DRI | Same |
| MeasuredAnalyte | Benzodiazepine and itsmetabolites | Same |
| Test Matrix | Urine | Same |
| Cutoff Levels | 200 ng/mL | Same |
| Methodology | Homogeneous EnzymeImmunoassay | Same |
| Reagents Form | Liquid ready-to-use. | Same |
| Antibody | Sheep Polyclonal antibody | Goat Polyclonal antibody |
| Storage | 2-8°C until expiration date. | Same |
| PrincipalOperator | Trained professionals | Same |
F. Test Principle
The DRI Benzodiazepine Assay is a homogeneous enzyme immunoassay with liquid readyto-use reagents. The assay uses a specific antibody which can detect most benzodiazepines and their metabolites in urine. The assay is based on the competition of an enzyme glucose-6-phosphate dehydrogenase (G6PDH) labeled drug and the drug from the urine sample for a fixed amount of specific antibody binding sites. In the absence of free drug from the sample, the enzyme-labeled drug is bound by the specific antibody and the enzyme activity is inhibited. This phenomenon creates a relationship between drug concentration in urine and the enzyme activity. The enzyme G6PDH activity is determined spectrophotometrically at 340 nm by measuring its ability to convert nicotinamide adenine dinucleotide (NAD) to NADH.
G. Summary of Supporting Data
1. Analytical Performance:
Performance is evaluated at the manufacturer's site on the AU680 clinical analyzer.
a) Precision
Precision studies were performed in accordance with CLSI Guideline EP05-A3. Samples were prepared by spiking Oxazepam into drug free urine at the cutoff, 25%, 50%. 75% and 100% above and below the cutoff and tested in both qualitative and semiquantitative modes. Results presented below were generated by testing all samples in
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replicates of 2, twice per day for 20 days, total n=80. The results are summarized in the table below.
| SpikedConcentration(ng/mL) | % of Cutoff(200 ng/mL) | LC-MS/MS(ng/mL) | Total Precision (n=80) | |
|---|---|---|---|---|
| # ofDeterminants | ImmunoassayResults(Negative/Positive) | |||
| 0 | -100% | N/A | 80 | 80/0 |
| 50 | -75% | 56.0 | 80 | 80/0 |
| 100 | -50% | 102.0 | 80 | 80/0 |
| 150 | -25% | 161.5 | 80 | 80/0 |
| 200 | 100% | 214.0 | 80 | 16/64 |
| 250 | +25% | 255.5 | 80 | 0/80 |
| 300 | +50% | 299.0 | 80 | 0/80 |
| 350 | +75% | 348.0 | 80 | 0/80 |
| 400 | +100% | 403.0 | 80 | 0/80 |
Quantitative Study Analysis
Semi-Quantitative Study Analysis
| SpikedConcentration(ng/mL) | % of Cutoff(200 ng/mL) | LC-MS/MS(ng/mL) | # ofDeterminants | Total Precision (n=80)ImmunoassayResults(Negative/Positive) |
|---|---|---|---|---|
| 0 | -100% | N/A | 80 | 80/0 |
| 50 | -75% | 56.0 | 80 | 80/0 |
| 100 | -50% | 102.0 | 80 | 80/0 |
| 150 | -25% | 161.5 | 80 | 80/0 |
| 200 | 100% | 214.0 | 80 | 27/53 |
| 250 | +25% | 255.5 | 80 | 0/80 |
| 300 | +50% | 299.0 | 80 | 0/80 |
| 350 | +75% | 348.0 | 80 | 0/80 |
| 400 | +100% | 403.0 | 80 | 0/80 |
b) Spike Recovery
The study was performed for 20 replicates. This study was carried out by testing spiked samples containing Oxazepam at the cutoff calibrator and control levels. The spiked samples were prepared by spiking Oxazepam into drug free urine. Samples were tested in both Qualitative and Semi-Quantitative mode. The qualitative results are summarized in the table below.
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| 150 ng/mL | 250 ng/mL | |
|---|---|---|
| Replicates | (n=20) | (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 |
| 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 |
Qualitative Data
c) Analytical Recovery and Linearity
Linearity studies were performed in accordance with CLSI Guideline EP06-A. To demonstrate the dilution linearity for purposes of sample dilution and quality control of the entire assay range, drug free urine was spiked to the high level calibrator using Oxazepam (1000 ng/mL) and diluted with drug free urine to generate 10 intermediate levels.
Each sample was run in replicates of five in semi-quantitative mode and the average was used to determine percent recovery compared to the expected target value. The percent recovery is summarized in the table below.
| Level | ExpectedConcentration(ng/mL) | ObservedConcentration(ng/mL) | Recovery (%) |
|---|---|---|---|
| 1 | 0 | -1.0 | N/A |
| 2 | 100 | 104.5 | 104.5 |
| 3 | 200 | 196.2 | 98.1 |
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| Level | ExpectedConcentration(ng/mL) | ObservedConcentration(ng/mL) | Recovery (%) |
|---|---|---|---|
| 4 | 300 | 314.7 | 104.9 |
| 5 | 400 | 455.3 | 113.8 |
| 6 | 500 | 565.2 | 113.0 |
| 7 | 600 | 661.0 | 110.2 |
| 8 | 700 | 764.7 | 109.2 |
| 9 | 800 | 872.1 | 109.0 |
| 10 | 900 | 937.3 | 104.1 |
| 11 | 1000 | 1024.9 | 102.5 |
d) Method Comparison and Accuracy
The method comparison study was performed in accordance with CLSI Guideline EP09-A3. One hundred and six patient samples were analyzed by the DRI Benzodiazepine Assay in both qualitative and semi-quantitative modes and the results were compared to LC-MS/MS. The overall concordance between LC-MS/MS and DRI Benzodiazepine Assay is 96.2%. The qualitative and semi-quantitative results are summarized in the tables below.
| CandidateDeviceResults | Negativeby LC-MS/MS | < 50% ofCutoffconcentrationby LC-MS/MS(< 100ng/mL) | Near CutoffNegative(Between 50%below thecutoff and thecutoffconcentrationas determinedby LC-MS/MS) (100- 199 ng/mL) | Near CutoffPositive(Between thecutoff and 50%above thecutoffconcentrationas determinedby LC-MS/MS)(200 – 300ng/mL) | High Positives(Greater than50% abovecutoffconcentration(> 300 ng/mL) |
|---|---|---|---|---|---|
| Positive | 0 | 1* | 3* | 5 | 45 |
| Negative | 48 | 2 | 2 | 0 | 0 |
Qualitative Accuracy study with LC-MS/MS as reference method
Negative agreement is 52/56 * 100% = 92.9% Positive agreement is 50/50 * 100% = 100%
Overall agreement is 102/106 * 100% = 96.2%
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Semi-Quantitative Mode Accuracy study with LC-MS/MS as reference method
| CandidateDeviceResults | Negativeby LC-MS/MS | < 50% ofCutoffconcentrationby LC-MS/MS(< 100ng/mL) | Near CutoffNegative(Between 50%below thecutoff and thecutoffconcentrationas determinedby LC-MS/MS) (100- 199 ng/mL) | Near CutoffPositive(Between thecutoff and 50%above thecutoffconcentrationas determinedby LC-MS/MS)(200 – 300ng/mL) | High Positives(Greater than50% abovecutoffconcentration(> 300 ng/mL) |
|---|---|---|---|---|---|
| Positive | 0 | 1* | 3* | 5 | 45 |
| Negative | 48 | 2 | 2 | 0 | 0 |
Negative agreement is 52/56 * 100% = 92.9% Positive agreement is 50/50 * 100% = 100% Overall agreement is 102/106 * 100% = 96.2%
*Discordant samples
| Sample ID | Qualitative | Semi-Quantitative | LC-MS/MS |
|---|---|---|---|
| Negative/Positive | Negative/Positive | Total BenzodiazepineParent Only (ng/mL) | |
| CA160606-045 | Positive | Positive | 86.20 |
| CA160926-057 | Positive | Positive | 175.08 |
| CA170605-001 | Positive | Positive | 151.52 |
| CA160908-003 | Positive | Positive | 192.87 |
These four samples are discordant because of the presence of Benzodiazepine metabolites. Sample CA160606-045 contains 3154.59 ng/mL 7-Aminoclonazepam .
Sample CA160926-057 contains 13.46 ng/mL a-Hydroxyalprazolam and 410.69 ng/mL 7-Aminoclonazepam.
Sample CA170605-001 contains 1.43 ng/mL a-Hydroxyalprazolam and 560.37 ng/mL 7-Aminoclonazepam.
Sample CA160908-003 contains 96.27 ng/mL α-Hydroxyalprazolam.
e) Specificity
The cross-reactivity of benzodiazepine compounds and their metabolites were evaluated by adding known amounts of each compound to drug-free negative urine. The results are summarized in the tables below.
Cross reactivity of benzodiazepine compounds and structurally unrelated compound*
| Structurally related and | Tested Concentration | Cross-reactivity |
|---|---|---|
| unrelated compounds | (ng/mL) | (%) |
| α-Hydroxyalprazolam | 110 | 182 |
| α-Hydroxytriazolam | 140 | 143 |
| Alprazolam | 110 | 182 |
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| Structurally related and | Tested Concentration | Cross-reactivity |
|---|---|---|
| unrelated compounds | (ng/mL) | (%) |
| 7-Aminoclonazepam | 2,500 | 8 |
| 7-Aminoflunitrazepam | 300 | 67 |
| 7-Aminonitrazepam | 300 | 67 |
| Bromazepam | 170 | 118 |
| Chlordiazepoxide | 700 | 29 |
| Clobazam | 150 | 133 |
| Clonazepam | 210 | 95 |
| Clorazepate | 135 | 148 |
| Delorazepam | 150 | 133 |
| Demoxepam | 220 | 91 |
| Desalkylflurazepam | 130 | 154 |
| Diazepam | 110 | 182 |
| Estazolam | 100 | 200 |
| Flunitrazepam | 120 | 167 |
| Flurazepam | 150 | 133 |
| 2-Hydroxyethylflurazepam | 120 | 167 |
| Lorazepam | 700 | 29 |
| Lorazepam glucuronide | 50,000 | <0.4 |
| Lormetazepam | 275 | 73 |
| Medazepam | 325 | 62 |
| Midazolam | 180 | 111 |
| Nitrazepam | 130 | 154 |
| Norchlordiazepoxide | 800 | 25 |
| Nordiazepam | 110 | 182 |
| *Oxaprozin | 125,000 | 0.16 |
| Oxazepam | 200 | 100 |
| Oxazepam glucuronide | 50,000 | 0.4 |
| Prazepam | 200 | 100 |
| Temazepam | 160 | 125 |
| Temazepam glucuronide | 50,000 | <0.4 |
| Triazolam | 130 | 154 |
Structurally unrelated compounds were evaluated by adding each substance to Oxazepam spiked at low control, 150 ng/mL (-25% of the cutoff concentration) and the high control, 250 ng/mL (+25% of the cutoff concentration), at the concentrations indicated. As shown in the table below, the Controls were detected accurately, Low Control as Negative and the High Control as Positive, indicating that all the compounds evaluated exhibited no significant cross-reactivity at the concentrations tested.
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Structurally unrelated compounds spiked at the concentration listed below into Low and High control urine
| Structurally Unrelated Compounds | Tested Concentration (ng/mL) | Spiked Oxazepam Level | ||
|---|---|---|---|---|
| Low Control Positive/Negative | High Control Positive/Negative | |||
| 6-Acetyl morphine | 100,000 | Negative | Positive | |
| 10,11 Dihydrocarbamazepine | 100,000 | Negative | Positive | |
| 11-nor-Δ9-THC-COOH | 100,000 | Negative | Positive | |
| Acetaminophen | 1,000,000 | Negative | Positive | |
| Acetylsalicylic acid | 1,000,000 | Negative | Positive | |
| Amitriptyline | 100,000 | Negative | Positive | |
| Amoxicillin | 100,000 | Negative | Positive | |
| Amphetamine | 100,000 | Negative | Positive | |
| Amisulpride | 100,000 | Negative | Positive | |
| Benzotropine Mesylate | 100,000 | Negative | Positive | |
| Benzoylecgonine | 100,000 | Negative | Positive | |
| Brompheniramine | 100,000 | Negative | Positive | |
| Buprenorphine | 100,000 | Negative | Positive | |
| Caffeine | 100,000 | Negative | Positive | |
| Captopril | 100,000 | Negative | Positive | |
| Chlorpromazine | 100,000 | Negative | Positive | |
| Chloroquine | 100,000 | Negative | Positive | |
| Cimetidine | 100,000 | Negative | Positive | |
| Clomipramine | 100,000 | Negative | Positive | |
| Codeine | 100,000 | Negative | Positive | |
| Desipramine | 100,000 | Negative | Positive | |
| Dextromethorphan | 100,000 | Negative | Positive | |
| Digoxin | 100,000 | Negative | Positive | |
| Dihydrocodeine | 100,000 | Negative | Positive | |
| Diphenhydramine | 500,000 | Negative | Positive | |
| Doxepine HCl | 100,000 | Negative | Positive | |
| EDDP | 100,000 | Negative | Positive | |
| EMDP | 25,000 | Negative | Positive | |
| Enalapril | 100,000 | Negative | Positive | |
| Fentanyl | 100,000 | Negative | Positive | |
| Fluoxetine | 500,000 | Negative | Positive | |
| Fluophenazine | 100,000 | Negative | Positive | |
| Haloperidol | 100,000 | Negative | Positive | |
| Heroin | 100,000 | Negative | Positive | |
| Hydrocodone | 100,000 | Negative | Positive | |
| Hydromorphone | 100,000 | Negative | Positive | |
| Hydroxychloroquine | 100,000 | Negative | Positive | |
| Hydroxyzine | 100,000 | Negative | Positive | |
| Structurally UnrelatedCompounds | TestedConcentration(ng/mL) | Spiked Oxazepam Level | ||
| Low ControlPositive/Negative | High ControlPositive/Negative | |||
| Ibuprofen | 100,000 | Negative | Positive | |
| Imipramine | 100,000 | Negative | Positive | |
| LAAM | 100,000 | Negative | Positive | |
| Levorphanol | 100,000 | Negative | Positive | |
| Levothyroxine | 100,000 | Negative | Positive | |
| Maprotiline | 100,000 | Negative | Positive | |
| Meperidine | 100,000 | Negative | Positive | |
| Methadone | 100,000 | Negative | Positive | |
| Methamphentamine | 100,000 | Negative | Positive | |
| Morphine | 100,000 | Negative | Positive | |
| Morphine-3β-D-glucuronide | 100,000 | Negative | Positive | |
| Morphine-6β-D-glucuronide | 100,000 | Negative | Positive | |
| Nalbuphine | 100,000 | Negative | Positive | |
| Nalorphine | 100,000 | Negative | Positive | |
| Naloxone | 100,000 | Negative | Positive | |
| Naltrexone | 100,000 | Negative | Positive | |
| Naproxen | 100,000 | Negative | Positive | |
| Nifedipine | 100,000 | Negative | Positive | |
| Norcodeine | 100,000 | Negative | Positive | |
| Norhydrocodone | 100,000 | Negative | Positive | |
| Norfluoxetine | 500,000 | Negative | Positive | |
| Noroxycodone | 100,000 | Negative | Positive | |
| Noroxymorphone | 100,000 | Negative | Positive | |
| Norpropoxyphene | 100,000 | Negative | Positive | |
| Norsertraline | 62,500 | Negative | Positive | |
| Nortryptiline | 100,000 | Negative | Positive | |
| Oxycodone | 100,000 | Negative | Positive | |
| Oxymorphone | 100,000 | Negative | Positive | |
| Paroxetine | 100,000 | Negative | Positive | |
| Perphenazine | 100,000 | Negative | Positive | |
| Phencyclidine | 100,000 | Negative | Positive | |
| Phenobarbital | 100,000 | Negative | Positive | |
| Procyclidine | 100,000 | Negative | Positive | |
| Propoxyphene | 100,000 | Negative | Positive | |
| Protriptyline | 100,000 | Negative | Positive | |
| Ranitidine | 100,000 | Negative | Positive | |
| Secobarbital | 100,000 | Negative | Positive | |
| Sertraline | 62,500 | Negative | Positive | |
| Sulpiride | 100,000 | Negative | Positive | |
| Structurally UnrelatedCompounds | TestedConcentration(ng/mL) | Spiked Oxazepam Level | ||
| Low ControlPositive/Negative | High ControlPositive/Negative | |||
| Tapentadol | 100,000 | Negative | Positive | |
| Thioridazine | 100,000 | Negative | Positive | |
| Tramadol | 100,000 | Negative | Positive | |
| Triprolidine | 100,000 | Negative | Positive | |
| Verapamil | 100,000 | Negative | Positive | |
| Zaleplon | 100,000 | Negative | Positive | |
| Zolpidem | 100,000 | Negative | Positive | |
| Zopiclone | 100,000 | Negative | Positive |
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f) Interference
The interference studies were performed in accordance with CLSI Guideline EP07-A2, using both Qualitative and Semi-quantitative modes. The potential interference of pH and endogenous physiologic substances on recovery of Oxazepam using DRI Benzodiazepine Assay was assessed by spiking known compounds of potentially interfering substances into the Low Control, 150 ng/mL (-25% of the cutoff concentration) and High Control, 250 ng/mL (+25% of the cutoff concentration). In the presence of the compounds listed below, the controls were detected accurately, indicating that these compounds did not show interference in the assay.
Interference substances
| Compound | Tested Concentration(mg/dL) | Spiked Oxazepam Level | |
|---|---|---|---|
| Low Control-25% of cutoff(150 ng/mL) | High Control+25% of cutoff(250 ng/mL) | ||
| Acetone | 500 | Negative | Positive |
| Ascorbic acid | 150 | Negative | Positive |
| Creatinine | 400 | Negative | Positive |
| Ethanol | 1000 | Negative | Positive |
| Galactose | 5 | Negative | Positive |
| Glucose | 1000 | Negative | Positive |
| Hemoglobin | 150 | Negative | Positive |
| Human serum albumin | 200 | Negative | Positive |
| Oxalic acid | 50 | Negative | Positive |
| Riboflavin | 3 | Negative | Positive |
| Sodium Chloride | 1000 | Negative | Positive |
| Urea | 1000 | Negative | Positive |
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| Compound | Tested Concentration(mg/dL) | Spiked Oxazepam Level | |
|---|---|---|---|
| Low Control-25% of cutoff(150 ng/mL) | High Control+25% of cutoff(250 ng/mL) | ||
| pH | pH | ||
| pH | 3.0 | Negative | Positive |
| pH | 4.0 | Negative | Positive |
| pH | 5.0 | Negative | Positive |
| pH | 6.0 | Negative | Positive |
| pH | 7.0 | Negative | Positive |
| pH | 8.0 | Negative | Positive |
| pH | 9.0 | Negative | Positive |
| pH | 10.0 | Negative | Positive |
| pH | 11.0 | Negative | Positive |
g) Specific Gravity
Drug free urine samples with specific gravity ranging in value within 1.000 to 1.030 were split and spiked with Oxazepam to a final concentration of either 150 ng/mL or 250ng/mL (the Low Control and High Concentrations, respectively). These samples were then evaluated in both qualitative and semi-quantitative modes. The Controls were detected accurately, indicating that no interference was observed.
| Specific Gravity | Spiked Oxazepam LevelLow Control | High Control |
|---|---|---|
| 1.004 | Negative | Positive |
| 1.005 | Negative | Positive |
| 1.007 | Negative | Positive |
| 1.010 | Negative | Positive |
| 1.011 | Negative | Positive |
| 1.013 | Negative | Positive |
| 1.019 | Negative | Positive |
| 1.023 | Negative | Positive |
| 1.025 | Negative | Positive |
| 1.029 | Negative | Positive |
H. Conclusion
The information supports a determination of substantial equivalence between DRI Benzodiazepine Assay and the predicate device Benzodiazepine Enzyme Immunoassay (K930529)
§ 862.3170 Benzodiazepine test system.
(a)
Identification. A benzodiazepine test system is a device intended to measure any of the benzodiazepine compounds, sedative and hypnotic drugs, in blood, plasma, and urine. The benzodiazepine compounds include chlordiazepoxide, diazepam, oxazepam, chlorzepate, flurazepam, and nitrazepam. Measurements obtained by this device are used in the diagnosis and treatment of benzodiazepine use or overdose and in monitoring levels of benzodiazepines to ensure appropriate therapy.(b)
Classification. Class II (special controls). A benzodiazepine 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).