LZI Oral Fluid Cannabinoids Enzyme Immunoassay, LZI Oral Fluid Cannabinoids Calibrators and LZI Oral Fluid Cannabinoids Controls

K141320 · Lin-Zhi International, Inc. · LDJ · May 28, 2015 · Clinical Toxicology

Device Facts

• Record ID: K141320
• Device Name: LZI Oral Fluid Cannabinoids Enzyme Immunoassay, LZI Oral Fluid Cannabinoids Calibrators and LZI Oral Fluid Cannabinoids Controls
• Applicant: Lin-Zhi International, Inc.
• Product Code: LDJ · Clinical Toxicology
• Decision Date: May 28, 2015
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 862.3870
• Device Class: Class 2

Indications for Use

The LZI Oral Fluid Cannabinoids Enzyme Immunoassay is intended for the qualitative and semi-quantitative determination of cannabinoids in neat human oral fluid, collected into the LZI Oral Fluid THC Collector, at the cut-off value of 4 ng/mL with Δ⁹-tetrahydrocannabinol (THC) as calibrators. The assay is designed for prescription use with a number of automated clinical chemistry analyzers. The semi-quantitative mode is for purposes of (1) enabling laboratories to determine an appropriate dilution of the specimen for confirmation by a confirmatory method such as GCMS and LCMS or (2) permitting laboratories to establish quality control procedures. The assay provides only a preliminary analytical result. A more specific alternative chemical method must be used in order to obtain a confirmed analytical result. Gas or liquid chromatography/mass spectrometry (GC/MS or LC/MS) is the preferred confirmatory method. Clinical consideration and professional judgment should be exercised with any drug of abuse test result, particularly when the preliminary test result is positive. The LZI Oral Fluid Cannabinoids Calibrators are for use as calibrators in the qualitative and semi-quantitative calibration of the LZI Oral Fluid Cannabinoids Enzyme Immunoassay at the cut-off value of 4 ng/mL. The LZI Oral Fluid Cannabinoids Controls are for use as assayed quality control materials to monitor the precision of the LZI Oral Fluid Cannabinoids Enzyme Immunoassay at the cut-off value of 4 ng/mL.

Device Story

LZI Oral Fluid Cannabinoids Enzyme Immunoassay is a homogeneous enzyme immunoassay kit; utilizes competitive binding between cannabinoids in oral fluid samples and enzyme-labeled cannabinoids for a fixed amount of antibody. Input: neat human oral fluid collected via LZI Oral Fluid THC Collector. Principle: enzyme activity (G6PDH) is inhibited when antibody binds to labeled drug; free drug in sample displaces labeled drug, increasing enzyme activity. Output: spectrophotometric absorbance change at 340 nm, proportional to drug concentration. Used in clinical laboratories; operated by trained laboratory personnel on automated clinical chemistry analyzers (e.g., Beckman AU400e). Provides preliminary screening results; requires confirmation by GC/MS or LC/MS. Assists clinicians in identifying potential cannabinoid presence to guide further diagnostic or confirmatory testing.

Clinical Evidence

Bench testing only. Precision evaluated per CLSI EP05-A2 (N=80). Method comparison performed against GC/MS using 83 clinical oral fluid samples (42 positive, 41 negative). Linearity and recovery studies conducted across 0-12 ng/mL range. Interference testing performed for endogenous, exogenous, and structurally unrelated compounds. Stability studies confirmed performance for 22 days refrigerated and 2 months frozen.

Technological Characteristics

Homogeneous enzyme immunoassay. Reagents: mouse monoclonal anti-cannabinoids antibody, G6PDH-labeled cannabinoids, G6P, NAD, stabilizers, sodium azide preservative. Form factor: liquid reagents for automated clinical chemistry analyzers. Detection: spectrophotometric at 340 nm. Calibration/Controls: synthetic oral fluid matrix with Δ⁹-THC. Storage: 2-8°C.

Indications for Use

Indicated for qualitative and semi-quantitative determination of cannabinoids in neat human oral fluid for prescription use. Intended for use with automated clinical chemistry analyzers to provide preliminary analytical results for cannabinoids at a 4 ng/mL cut-off.

Regulatory Classification

Identification

A cannabinoid test system is a device intended to measure any of the cannabinoids, hallucinogenic compounds endogenous to marihuana, in serum, plasma, saliva, and urine. Cannabinoid compounds include delta-9-tetrahydrocannabinol, cannabidiol, cannabinol, and cannabichromene. Measurements obtained by this device are used in the diagnosis and treatment of cannabinoid use or abuse and in monitoring levels of cannabinoids during clinical investigational use.

Special Controls

*Classification.* Class II (special controls). A cannabinoid 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).

Predicate Devices

• Lin-Zhi International, Inc. Cannabinoid (cTHC) Enzyme Immunoassay, Calibrators and Controls for Hitachi 717 Systems (k110239)

Submission Summary (Full Text)

{0}

1

510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION
DECISION MEMORANDUM
ASSAY ONLY TEMPLATE

A. 510(k) Number:
k141320

B. Purpose for Submission:
New Device

C. Measurand:
Cannabinoids

D. Type of Test:
Qualitative and Semi-Quantitative Enzyme Immunoassay

E. Applicant:
Lin-Zhi International, Inc.

F. Proprietary and Established Names:
LZI Oral Fluid Cannabinoids Enzyme Immunoassay
LZI Oral Fluid Cannabinoids Calibrators
LZI Oral Fluid Cannabinoids Controls

G. Regulatory Information:
1. Regulation section:
21 CFR 862.3870, Cannabinoid Test System
21 CFR 862.3200, Clinical Toxicology Calibrator
21 CFR 862.3280, Clinical Toxicology Control Material
2. Classification:
Class II (Test system, Calibrator)

{1}

Class I, reserved (Control Material)

3. Product code:
LDJ, enzyme immunoassay, cannabinoids
DLJ, calibrators, drug-specific
LAS, drug-specific control material

4. Panel:
Toxicology (91)

H. Intended Use:

1. Intended use(s):
See Indications for Use below.

2. Indication(s) for use:
The LZI Oral Fluid Cannabinoids Enzyme Immunoassay is intended for the qualitative and semi-quantitative determination of cannabinoids in neat human oral fluid, collected into the LZI Oral Fluid THC Collector, at the cut-off value of 4 ng/mL with Δ⁹-tetrahydrocannabinol (THC) as calibrators. The assay is designed for prescription use with a number of automated clinical chemistry analyzers.

The semi-quantitative mode is for purposes of (1) enabling laboratories to determine an appropriate dilution of the specimen for confirmation by a confirmatory method such as GCMS and LCMS or (2) permitting laboratories to establish quality control procedures.

The assay provides only a preliminary analytical result. A more specific alternative chemical method must be used in order to obtain a confirmed analytical result. Gas or liquid chromatography/mass spectrometry (GC/MS or LC/MS) is the preferred confirmatory method. Clinical consideration and professional judgment should be exercised with any drug of abuse test result, particularly when the preliminary test result is positive.

The LZI Oral Fluid Cannabinoids Calibrators are for use as calibrators in the qualitative and semi-quantitative calibration of the LZI Oral Fluid Cannabinoids Enzyme Immunoassay at the cut-off value of 4 ng/mL.

The LZI Oral Fluid Cannabinoids Controls are for use as assayed quality control materials to monitor the precision of the LZI Oral Fluid Cannabinoids Enzyme Immunoassay at the cut-off value of 4 ng/mL.

2

{2}

3. Special conditions for use statement(s):

Prescription Use Only

4. Special instrument requirements:

The assay is designed for prescription use with a number of clinical chemistry analyzers. Performance data was obtained using the Beckman AU400e automatic clinical analyzer.

I. Device Description:

The LZI Oral Fluid Cannabinoids Enzyme Immunoassay is a kit comprised of two reagents, R1 and R2, which are bottled separately but sold together within the kit.

The R1 solution contains mouse monoclonal anti-Cannabinoids antibody, glucose-6-phosphate (G6P) nicotinamide adenine dinucleotide (NAD), stabilizers, and sodium azide (0.09%) as a preservative. The R2 solution contains glucose-6-phosphate dehydrogenase (G6PDH) labeled with Cannabinoids, stabilizers, in buffer with sodium azide (0.09%) as preservative.

The LZI Oral Fluid Cannabinoids (THC) calibrators designated for use at the 4 ng/mL cut-off contain 0, 2, 4, 6, and 12 ng/mL of Δ⁹-tetrahydrocannabinol (THC) in synthetic oral fluid with sodium azide (0.09%) as preservative. The LZI Oral Fluid Cannabinoids (THC) Controls contain 3 and 5 ng/mL of Δ⁹-tetrahydrocannabinol (THC) in synthetic oral fluid with sodium azide (0.09%) as preservative. These five calibrators and two controls are sold as individual bottles.

J. Substantial Equivalence Information:

1. Predicate device name(s):

LZI Cannabinoids (cTHC) Enzyme Immunoassay
LZI Cannabinoids (cTHC) Drugs of Abuse (DAU) Calibrators
LZI Cannabinoids (cTHC) Drugs of Abuse (DAU) Controls

2. Predicate 510(k) number(s):

K110239

3. Comparison with predicate:

{3}

| Similarities | | |
| --- | --- | --- |
| Item | Candidate Device | Predicate Device |
| Intended Use | Intended for the qualitative and semi-quantitative determination of Cannabinoids | Same |
| Methodology | Enzyme immunoassay | Same |
| Storage (Calibrator and Control) | 2-8 °C until expiration date | Same |
| Differences | | |
| --- | --- | --- |
| Item | Candidate Device | Predicate Device |
| Cut-off | 4 ng/mL | 25, 50, 100 ng/ml |
| Matrix | Oral Fluid | Urine |
| Target Analyte | Δ⁹-tetrahydrocannabinol (THC) | 11-nor-Δ⁹-THC-9-carboxylic acid |
| Calibrator Levels | 5 Levels (0, 2, 4, 6, 12 ng/mL) | THC 25: 5 Levels (0, 12.5, 25, 37.5, 50 ng/mL) THC 50: 5 Levels (0, 25, 50, 75, 100 ng/mL) THC 100: 5 Levels (0, 50, 100, 150, 200 ng/mL) |
| Control Levels | 2 Levels (3 ng/mL, 5 ng/mL) | THC 25: 2 Levels, (18.75, 31.25 ng/mL) THC 50: 2 Levels, (37.5 ng/mL, 62.5 ng/mL) THC 100: 2 Levels, (75 ng/mL, 125 ng/mL) |

# K. Standard/Guidance Document Referenced (if applicable):

CLSI EP05-A2: Evaluation of Precision Performance of Quantitative Measurement Methods

# L. Test Principle:

The LZI Oral Fluid Cannabinoids assay is a homogeneous enzyme immunoassay with ready to use liquid reagents. The assay is based on competition between drug in the sample and drug labeled with the enzyme glucose-6-phosphate dehydrogenase (G6PDH) for a fixed amount of antibody in the reagents. Enzyme activity decreases upon binding to the antibody, and the drug concentration in the sample is measured in terms of enzyme activity. In the absence of drug in the sample, cannabinoid derivative-labeled G6PDH conjugate is bound to antibody, and the enzyme activity is inhibited. On the other hand, when free drug is present in the sample, antibody would bind to free drug, the unbound cannabinoid derivative-labeled

{4}

G6PDH then exhibits its maximal enzyme activity. Active enzyme converts nicotinamide adenine dinucleotide (NAD) to NADH, resulting in an absorbance change that can be measured spectrophotometrically at $340~\mathrm{nm}$ .

# M. Performance Characteristics (if/when applicable):

# 1. Analytical performance:

# a. Precision/Reproducibility:

Precision was performed and evaluated according to the CLSI Document EP5-A2. Precision studies were conducted on the Beckman AU400e analyzer using samples containing $\Delta^9$ -tetrahydrocannabinol (THC). Samples were prepared by spiking a neat human oral fluid pool collected into LZI Oral Fluid THC Collectors with $\Delta^9$ -tetrahydrocannabinol (THC) for 8 target concentrations and a negative control. Samples were tested in 2 replicates per run, 2 runs per day for 20 days, total N=80. The qualitative and semi-quantitative results confirmed by GC/MS. The results are presented below:

Qualitative Precision Data:

| | | Within Run Precision | | Total Precision | |
| --- | --- | --- | --- | --- | --- |
| Sample Concentration | % of Cutoff | Number of Determinations | Immunoassay Result | Number of Determination | Immunoassay Result |
| 0 ng/mL | -100.0% | 20 | 20 Negative | 80 | 80 Negative |
| 1 ng/mL | -75.0% | 20 | 20 Negative | 80 | 80 Negative |
| 2 ng/mL | -50.0% | 20 | 20 Negative | 80 | 80 Negative |
| 3 ng/mL | -25.0% | 20 | 20 Negative | 80 | 80 Negative |
| 4 ng/mL | 0% | 20 | 18 Pos / 2 Neg | 80 | 59 Pos / 21 Neg |
| 5 ng/mL | +25.0% | 20 | 20 Positive | 80 | 80 Positive |
| 6 ng/mL | +50.0% | 20 | 20 Positive | 80 | 80 Positive |
| 7 ng/mL | +75.0% | 20 | 20 Positive | 80 | 80 Positive |
| 8 ng/mL | +100.0% | 20 | 20 Positive | 80 | 80 Positive |

Semi-Quantitative Precision Data:

| | | Within Run Precision | | Total Precision | |
| --- | --- | --- | --- | --- | --- |
| Sample Concentration | % of Cutoff | Number of Determinations | Immunoassay Result | Number of Determination | Immunoassay Result |
| 0 ng/mL | -100.0% | 20 | 20 Negative | 80 | 80 Negative |
| 1 ng/mL | -75.0% | 20 | 20 Negative | 80 | 80 Negative |
| 2 ng/mL | -50.0% | 20 | 20 Negative | 80 | 80 Negative |
| 3 ng/mL | -25.0% | 20 | 20 Negative | 80 | 80 Negative |
| 4 ng/mL | 0% | 20 | 17 Pos / 3 Neg | 80 | 54 Pos / 26 Neg |

{5}

6

| 5 ng/mL | +25.0% | 20 | 20 Positive | 80 | 80 Positive |
| --- | --- | --- | --- | --- | --- |
| 6 ng/mL | +50.0% | 20 | 20 Positive | 80 | 80 Positive |
| 7 ng/mL | +75.0% | 20 | 20 Positive | 80 | 80 Positive |
| 8 ng/mL | +100.0% | 20 | 20 Positive | 80 | 80 Positive |

b. Linearity/assay reportable range:

Recovery studies were performed by serially diluting a spiked neat human oral fluid pool containing $\Delta^9$-tetrahydrocannabinol (THC). Each sample from these studies was run in 10 replicates on the Beckman AU400e analyzer. The results were averaged and compared to the expected result and the percent recovery was calculated. The linearity results are presented below:

| % Dilution | Expected Value (ng/mL) | Observed Value (ng/mL) | % Recovery |
| --- | --- | --- | --- |
| 100.0% | 0 | -0.67 | N/A |
| 91.7% | 1 | 0.49 | 49.4% |
| 83.3% | 2 | 1.79 | 89.6% |
| 75.0% | 3 | 2.70 | 89.9% |
| 66.7% | 4 (cutoff) | 3.57 | 89.2% |
| 58.3% | 5 | 4.54 | 90.8% |
| 50.0% | 6 | 5.18 | 86.3% |
| 41.7% | 7 | 6.47 | 92.4% |
| 33.3% | 8 | 7.11 | 88.8% |
| 25.0% | 9 | 8.18 | 90.9% |
| 16.7% | 10 | 8.87 | 88.7% |
| 0.0% | 12 | 12.34 | 102.8% |

c. Traceability, Stability, Expected values (controls, calibrators, or methods):

Traceability and value assignment and Stability

A stock solution of $1000\ \mu\mathrm{g/mL}\ \Delta^9$-tetrahydrocannabinol (THC) purchased from a commercial source is spiked into the calibrator and controls to the desired concentration. The concentration of the calibrator and controls are determined by GC/MS. Purity determination and gravimetric preparation using balances calibrated with NIST traceable weights ensure the accuracy of the stock standard solution. The sponsor claims in-use stability (open-recapped) of 12 months at 2 to $8^{\circ}\mathrm{C}$ for the calibrator and controls and a closed vial stability (shelf life) of at least 6 months when stored at 2 to $8^{\circ}\mathrm{C}$. Closed-vial real-time stability studies are ongoing. The study protocols, summary of the results and acceptance criteria were reviewed and found to be adequate.

Shipping / Recovery Study

A shipping study was performed to demonstrate the recovery of drug from oral fluid when collected in the LZI Oral Fluid Collector tube by testing expected transport conditions. Conditions simulating transport to 3 different destinations with varied

{6}

weather conditions [(1) cold, 2 to $8^{\circ}\mathrm{C}$ (2) ambient room temperature $\sim 25^{\circ}\mathrm{C}$ (3) $30^{\circ}\mathrm{C}]$ were used. Three sets of pooled negative oral fluid samples (30 mL each) were spiked with $\Delta^{9}$ -tetrahydro-cannabinol (THC) to 50, 75, 100, 125, 150, and $300\%$ of the cutoff concentration to get six target concentrations of 2, 3, 4, 5, 6, and $12\mathrm{ng/mL}$ , respectively. These samples served as pre-shipping controls for analyte recovery (Day 1). The samples at each concentration were then pipetted (3.0 mL) into individual amber glass vials and kept at three temperatures [(1) cold, 2 to $8^{\circ}\mathrm{C}$ (2) ambient room temperature $\sim 25^{\circ}\mathrm{C}$ (3) $30^{\circ}\mathrm{C}]$ over 3 days (72 hours). After 72 hours, all samples were brought to room temperature and tested with the LZI Oral Fluid Cannabinoid Enzyme Immunoassay and by GC/MS. Percent recoveries (based on GCMS measurements) under various shipping conditions are shown in the table below:

| Target Concentration | Shipping Condition | Concentration by GC/MS (ng/mL) | % Recovery |
| --- | --- | --- | --- |
| 2 ng/mL | Cold (2 - 8°C) | 2.22 | 111% |
| | Room Temperature (17 - 25°C) | 2.16 | 108% |
| | 30°C | 1.70 | 85% |
| 3 ng/mL | Cold (2 - 8°C) | 2.95 | 98% |
| | Room Temperature (17 - 25°C) | 3.31 | 110% |
| | 30°C | 2.63 | 88% |
| 4 ng/mL | Cold (2 - 8°C) | 4.2 | 105% |
| | Room Temperature (17 - 25°C) | 4.6 | 115% |
| | 30°C | 5.0 | 125% |
| 5 ng/mL | Cold (2 - 8°C) | 5.04 | 101 |
| | Room Temperature (17 - 25°C) | 5.39 | 108 |
| | 30°C | 4.48 | 90% |
| 6 ng/mL | Cold (2 - 8°C) | 6.5 | 108% |
| | Room Temperature (17 - 25°C) | 6.6 | 110% |
| | 30°C | 7.8 | 130% |
| 12 ng/mL | Cold | 12.9 | 108% |

{7}

8

| | (2 – 8° C) | | |
| --- | --- | --- | --- |
| | Room Temperature (17 – 25° C) | 13.6 | 113% |
| | 30° C | 13.7 | 114% |

The sponsor’s labeling instructs users that samples that cannot be analyzed immediately should be stored in amber glass vials and may be refrigerated at 2-8 °C for up to 22 days or frozen (-20 °C) for up to 2 months. The labeling also states that samples to be shipped should always be shipped cold (2-8 °C), packed in gel ice and shipped for next day delivery (within 24 hours), with a prominent note that failure to do so may result in a significant decrease in recovery.

## Sample Storage and Stability Study

Three sets of pooled negative oral fluid samples (30 mL each) collected with the LZI Oral Fluid Cannabinoids collector were spiked in amber glass vials with Δ⁹-tetrahydrocannabinol (THC) to 50, 75, 100, 125, 150, and 300% of the cutoff concentration to get six target concentrations of 2, 3, 4, 5, 6, and 12 ng/mL, respectively). Testing was performed on samples stored under various conditions (room temperature, refrigerated and 30 °C) on day 1, 4, 8, 11, 15, 22, and 29.

No degradation was seen at the cold (2 – 8° C) condition over 22 days. Percent recoveries at room temperature (17-25 °C) and at 30° C vs. the cold condition at various concentrations and time points were determined and percent recoveries ranged from 98.5 to 101.3% at Day 22 for room temperature and from 96.7 to 101.4% at Day 22 for 30° C. The manufacturer claims that Δ⁹-tetrahydrocannabinol (THC) saliva samples are stable for up to 22 days when stored refrigerated at 2 to 8 °C and for up to two months when stored frozen (at -20 °C) in amber glass vials. The stability claim at -20 °C was supported from the scientific literature.

d. Detection limit:

Not applicable.

e. Analytical specificity:

The effect of endogenous substances, exogenous substances and structurally unrelated compounds was evaluated by adding these compounds (at the concentrations specified below) to neat oral fluid (collected with the LZI Oral Fluid THC collectors) at 2 ng/mL and 6 ng/mL (±50% of the assay cut-off). Drug-free oral fluid samples were used as test controls. Data was collected on the Beckman AU400e analyzer and is summarized below:

{8}

Interference (Endogenous compounds):

| Interfering Substance | Compound Concentration | -50% Cutoff Concentration (2 ng/mL) | +50% Cutoff Concentration (6 ng/mL) |
| --- | --- | --- | --- |
| Ascorbic Acid | 0.5 mg/mL | Neg | Pos |
| Ascorbic Acid | 1.5 mg/mL | Neg | Pos |
| Ascorbic Acid | 2 mg/mL | Neg | Pos |
| Ascorbic Acid | 15 mg/mL | Neg | Neg |
| Bilirubin | 0.05 mg/mL | Neg | Pos |
| Cholesterol | 0.45 mg/mL | Neg | Pos |
| Cotinine | 0.01 mg/mL | Neg | Pos |
| γ-globulin | 0.8 mg/mL | Neg | Pos |
| hemoglobin | 0.6 mg/mL | Neg | Pos |
| Human Serum Albumin | 5 mg/mL | Neg | Pos |
| Nicotine | 0.03 mg/mL | Neg | Pos |
| Sodium Chloride | 18 mg/mL | Neg | Pos |
| pH 3 | - | Neg | Neg |
| pH 4 | - | Neg | Neg |
| pH 5 | - | Neg | Neg |
| pH 6 | - | Neg | Pos |
| pH 7 | - | Neg | Pos |
| pH 8 | - | Neg | Pos |
| pH 9 | - | Neg | Pos |
| pH 10 | - | Neg | Pos |

Interference (Exogenous compounds):

| Interfering Substance | Concentration (%V/V) | 0 ng/mL | -50% Cutoff Concentration (2 ng/mL) | +50% Cutoff Concentration (6 ng/mL) |
| --- | --- | --- | --- | --- |
| Alcohol (Ethanol) | 1 | Neg | Neg | Pos |
| Alcohol (Ethanol) | 2 | Neg | Neg | Pos |
| Alcohol (Ethanol) | 3 | Neg | Neg | Pos |
| Alcohol (Ethanol) | 5 | Neg | Neg | Neg |
| Coffee | 2 | Neg | Neg | Pos |
| Cough syrup | 5 | Neg | Neg | Pos |

{9}

| Interfering Substance | Concentration (%V/V) | 0 ng/mL | -50% Cutoff Concentration (2 ng/mL) | +50% Cutoff Concentration (6 ng/mL) |
| --- | --- | --- | --- | --- |
| Cranberry Juice | 5 | Neg | Neg | Pos |
| Sugar | 25 mg/mL | Neg | Neg | Pos |
| Sugar | 50 mg/mL | Neg | Neg | Pos |
| Mouthwash (Blue) | 1 | Neg | Neg | Pos |
| Mouthwash (Yellow) | 1 | Neg | Neg | Pos |
| Orange juice | 5 | Neg | Neg | Pos |
| Soft drink (Coke) | 5 | Neg | Neg | Pos |
| Tea | 5 | Neg | Neg | Pos |
| Toothpaste 1 | 2 | Neg | Neg | Pos |
| Toothpaste 2 | 2 | Neg | Neg | Pos |
| Water | 5 | Neg | Neg | Pos |
| Reduced Fat Milk (2% milk fat) | 5 | * | * | * |
| Reduced Fat Milk (2% milk fat) | 2 | Neg | Neg | Neg |
| Reduced Fat Milk (2% milk fat) | 1 | Neg | Neg | Pos |
| Non-fat Milk (0% milkfat) | 5 | Neg | Neg | Pos |
| Non-fat Milk (0% milkfat) | 2 | Neg | Neg | Pos |

* Showed error due to cloudy sample, high OD.

Labeling indicates that there is interference with the test with $2\%$ Reduced Fat Milk at concentrations above $1\% \mathrm{V} / \mathrm{V}$ , ethanol at concentrations above $3\% \mathrm{V} / \mathrm{V}$ , ascorbic acid at concentrations above $2\mathrm{mg / mL}$ , and at $\mathsf{pH}$ levels 3, 4, and 5. The ascorbic acid concentration and $\mathsf{pH}$ levels showing interference are outside of the normal physiological range for oral fluid.

Interference (Structurally Unrelated Compounds):

| Structurally Unrelated Compounds | Concentration (ng/mL) | Result | -50% Cutoff Concentration (2 ng/mL) | +50% Cutoff Concentration (6 ng/mL) |
| --- | --- | --- | --- | --- |
| Acetaminophen | 25,000 | 0.001% | Neg | Pos |
| Acetylsalicylic Acid | 25,000 | 0.001% | Neg | Pos |
| Amitryptyline | 25,000 | 0.002% | Neg | Pos |
| Amobarbital | 12,500 | 0.004% | Neg | Pos |

{10}

| Structurally Unrelated Compounds | Concentration (ng/mL) | Result | -50% Cutoff Concentration (2 ng/mL) | +50% Cutoff Concentration (6 ng/mL) |
| --- | --- | --- | --- | --- |
| d-Amphetamine | 50,000 | 0.000% | Neg | Pos |
| Benzoylecgonine | 25,000 | 0.002% | Neg | Pos |
| Burpropion | 50,000 | 0.002% | Neg | Pos |
| Caffeine | 50,000 | 0.002% | Neg | Pos |
| Chlorpheniramine | 50,000 | 0.001% | Neg | Pos |
| Chlorpromazine | 25,000 | 0.002% | Neg | Pos |
| Cocaine | 50,000 | 0.001% | Neg | Pos |
| Codeine | 50,000 | 0.001% | Neg | Pos |
| Dextromethorphan | 50,000 | 0.001% | Neg | Pos |
| Ecgonine Methyl Ester | 50,000 | 0.001% | Neg | Pos |
| d,l-Ephedrine | 50,000 | 0.001% | Neg | Pos |
| Imipramine | 50,000 | 0.002% | Neg | Pos |
| JWH-018(1-pentyl-3(1-naphthoyl)indole) | 12,500 | 0.006% | Neg | Pos |
| JWH-073(1-butyl-3(1-naphthoyl)indole) | 25,000 | 0.001% | Neg | Pos |
| Lidocaine | 50,000 | 0.001% | Neg | Pos |
| Meperidine | 50,000 | 0.002% | Neg | Pos |
| Methadone | 50,000 | 0.001% | Neg | Pos |
| d-Methamphetamine | 50,000 | 0.001% | Neg | Pos |
| Methaqualone | 50,000 | 0.001% | Neg | Pos |
| Morphine | 50,000 | 0.001% | Neg | Pos |
| Nortriptyline | 50,000 | 0.001% | Neg | Pos |
| Oxazepam | 50,000 | 0.001% | Neg | Pos |
| Phencyclidine | 50,000 | 0.001% | Neg | Pos |
| Phenobarbital | 50,000 | 0.001% | Neg | Pos |
| Promethazine | 25,000 | 0.003% | Neg | Pos |
| d-Propoxyphene | 50,000 | 0.001% | Neg | Pos |
| Ranitidine | 50,000 | 0.002% | Neg | Pos |
| Secobarbital | 25,000 | 0.003% | Neg | Pos |
| Valproic Acid | 50,000 | 0.002% | Neg | Pos |

{11}

Potential cross-reactants were evaluated by spiking drug-free oral fluid samples with structurally related compounds. Concentrations equivalent in assay reactivity to the 4 ng/mL assay cut-off and the % cross-reactivity are listed in the table below.

Cross-reactivity (Structurally Related Compounds):

| Compound | Concentration approximately equal to the cutoff (ng/mL) | % Cross-reactivity |
| --- | --- | --- |
| 8-beta-hydroxy-Δ⁹-THC | 4.4 | 90.8 |
| 8-beta-11-dihydroxy-Δ⁹-THC | 4.6 | 86.1 |
| Cannabidiol | 388.3 | 1.0 |
| Cannabinol | 8.9 | 44.8 |
| exo-THC | 3.4 | 117.1 |
| l-11-Hydroxy-Δ⁹-THC | 3.8 | 106.7 |
| l-11-Nor-Δ⁹-THC-9- Carboxylic Acid | 1.9 | 212.3 |
| l-11-Nor-Δ⁹-THC-9- Carboxylic Acyl-Glucuronide | 111.1 | 3.6 |
| Δ⁸-THC | 3.8 | 104.0 |
| Δ⁹-THC | 4.6 | 87.6 |

f. Assay cut-off:
Characterization of how the device performs analytically around the claimed cut-off concentration appears in the precision/reproducibility section above (M.1.a.).

2. Comparison studies:

a. Method comparison with predicate device:
Forty two (42) positive and forty one (41) negative unaltered oral fluid samples were evaluated by the LZI Oral Fluid Cannabinoid Enzyme Immunoassay using the Beckman AU400e clinical analyzer and compared to GC/MS. All samples were collected using the LZI Oral Fluid Collector and were processed following insert instructions. Results from the study are presented below:

Qualitative Method Comparison Data:

| 4 ng/mL Cutoff | Negative | < 50 % of the cutoff concentration by LC/MS analysis | Near Cutoff Negative (Between 50 % below the cutoff and the cutoff concentration) | Near Cutoff Positive (Between the cutoff and 50 % above the cutoff concentration) | High Positive (Greater than 50 % above the cutoff concentration) |
| --- | --- | --- | --- | --- | --- |
| Positive | 0 | 0 | 2* | 5 | 35 |
| Negative | 20 | 13 | 6 | 2** | 0 |

{12}

| GC/MS THC concentration (ng/mL) | Assay Cut-off | EIA Qualitative Result |
| --- | --- | --- |
| 3.6* | 4 ng/mL | + |
| 3.9* | | + |
| 4.1** | | - |
| 4.8** | | - |

Semi-Quantitative Method Comparison Data:

| 4 ng/mL Cutoff | Negative | < 50 % of the cutoff concentration by LC/MS analysis | Near Cutoff Negative (Between 50 % below the cutoff and the cutoff concentration) | Near Cutoff Positive (Between the cutoff and 50 % above the cutoff concentration) | High Positive (Greater than 50 % above the cutoff Concentration) |
| --- | --- | --- | --- | --- | --- |
| Positive | 0 | 0 | 1* | 6 | 35 |
| Negative | 20 | 13 | 7 | 1** | 0 |
| GC/MS THC concentration (ng/mL) | Assay Cut-off | EIA Semi-Quantitative Result |
| --- | --- | --- |
| 2.8* | 4 ng/mL | + |
| 4.1** | | - |

b. Matrix comparison: Not applicable.

3. Clinical studies:

a. Clinical Sensitivity: Not applicable.
b. Clinical specificity: Not applicable.
c. Other clinical supportive data (when a. and b. are not applicable): Not applicable.

4. Clinical cut-off: Not applicable.

5. Expected values/Reference range: Not applicable.

{13}

N. Proposed Labeling:

The labeling is sufficient and it satisfies the requirements of 21 CFR Part 809.10.

O. Conclusion:

The submitted information in this premarket notification is complete and supports a substantial equivalence decision.

14