← Product Code [DIO](/submissions/TX/subpart-d%E2%80%94clinical-toxicology-test-systems/DIO) · K112071

# WONDFO COCAINE URINE TEST MODEL W10-CU, W10-P, WONDFO METHAMPHETAMINE URINE TEST MODEL W11-CU, W11-P (K112071)

_Guangzhou Wondfo Biotech Co., Ltd. · DIO · Sep 23, 2011 · Clinical Toxicology · SESE_

**Canonical URL:** https://fda.innolitics.com/submissions/CH/subpart-d%E2%80%94clinical-toxicology-test-systems/DIO/K112071

## Device Facts

- **Applicant:** Guangzhou Wondfo Biotech Co., Ltd.
- **Product Code:** [DIO](/submissions/TX/subpart-d%E2%80%94clinical-toxicology-test-systems/DIO.md)
- **Decision Date:** Sep 23, 2011
- **Decision:** SESE
- **Submission Type:** Traditional
- **Regulation:** 21 CFR 862.3250
- **Device Class:** Class 2
- **Review Panel:** Clinical Toxicology

## Indications for Use

Wondfo Cocaine Urine Test is an immunochromatographic assay for the qualitative determination of Benzolecgonine in human urine at a cutoff concentration of 300 ng/mL. The test is available in a dip card format and a cup format. It is intended for prescription use and over the counter use. The test provides only preliminary test results. A more specific alternative chemical method must be used in order to obtain a conformed analytical result. GC/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 result is positive. Wondfo Methamphetamine Urine Test is an immunochromatographic assay for the qualitative determination of D(+)-Methamphetamine in human urine at a cutoff concentration of 1000 ng/mL. The test is available in a dip card format and a cup format. It is intended for prescription use and over the counter use. The test provides only preliminary test results. A more specific alternative chemical method must be used in order to obtain a conformed analytical result. GC/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 result is positive.

## Device Story

Wondfo Cocaine and Methamphetamine Urine Tests are lateral flow immunoassays for qualitative drug detection in human urine. Available in dip card or integrated cup formats. Principle: competitive binding; urine sample migrates via capillary action; drug/metabolite competes with immobilized drug conjugate for limited anti-drug antibody binding sites. Result: negative (rose-pink band in test zone); preliminary positive (no band in test zone). Control line confirms proper wicking. Used in clinical or home settings; operated by healthcare professionals or lay users. Results read visually at 5 minutes. Preliminary results require confirmation via GC/MS. Benefits: rapid, point-of-care screening for drug abuse; aids clinical decision-making regarding patient management.

## Clinical Evidence

No clinical trials performed. Evidence consists of analytical performance studies (precision, specificity, interference, cutoff verification) and a lay-user study. Lay-user study (n=140 per format) compared user results to GC/MS across various concentrations (±75% of cutoff). Overall agreement with GC/MS ranged from 96.4% to 97.8%. Analytical specificity evaluated cross-reactivity with structurally related and unrelated compounds. Bench testing confirmed performance at claimed cutoffs.

## Technological Characteristics

Lateral flow immunochromatographic assay; competitive binding principle; monoclonal antibody-dye conjugate (mouse) with gold chloride; fixed drug-protein conjugate; anti-mouse IgG polyclonal antibody. Formats: dip card, cup. No electronic components or software.

## Regulatory Identification

A cocaine and cocaine metabolite test system is a device intended to measure cocaine and a cocaine metabolite (benzoylecgonine) in serum, plasma, and urine. Measurements obtained by this device are used in the diagnosis and treatment of cocaine use or overdose.

## Special Controls

*Classification.* Class II (special controls). A cocaine and cocaine metabolite 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

- Acon Laboratories, Inc. One Step Drug Screen Test (k020771)

## Submission Summary (Full Text)

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>
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{0}

1

# 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY ASSAY ONLY TEMPLATE

A. 510(k) Number:
k112071

B. Purpose for Submission:
New Device

C. Measurand:
Cocaine, Methamphetamine

D. Type of Test:
Qualitative lateral flow chromatographic Immunoassay

E. Applicant:
Guangzhou Wondfo Biotech Co., Ltd.

F. Proprietary and Established Names:
Wondfo Cocaine Urine Test
Wondfo Methamphetamine Urine Test

G. Regulatory Information:

|  Product Code | Classification | Regulation Section | Panel  |
| --- | --- | --- | --- |
|  DIO | Class II | 21 CFR §862.3250: Cocaine and Cocaine Metabolites Test System | Toxicology (91)  |
|  LAF | Class II | 21 CFR §862.3610: Methamphetamine Test System | Toxicology (91)  |

H. Intended Use:
1. Intended use(s):

{1}

See Indications for use below.

2. **Indication(s) for use:**

**Wondfo Cocaine Urine Test:**

Wondfo Cocaine Urine Test is an immunochromatographic assay for the qualitative determination of Benzolecgonine in human urine at a cutoff concentration of 300 ng/mL. The test is available in a dip card format and a cup format. It is intended for prescription use and over the counter use.

The test provides only preliminary test results. A more specific alternative chemical method must be used in order to obtain a conformed analytical result. GC/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 result is positive.

**Wondfo Methamphetamine Urine Test:**

Wondfo Methamphetamine Urine Test is an immunochromatographic assay for the qualitative determination of D(+)-Methamphetamine in human urine at a cutoff concentration of 1000 ng/mL. The test is available in a dip card format and a cup format. It is intended for prescription use and over the counter use.

The test provides only preliminary test results. A more specific alternative chemical method must be used in order to obtain a conformed analytical result. GC/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 result is positive.

3. **Special conditions for use statement(s):**

For prescription and over the counter use

4. **Special instrument requirements:**

Not applicable, as the devices are visually-read single-use devices.

I. **Device Description:**

**Wondfo Cocaine Urine Test:**

Two Different Formats:

1) Urine cups with built in test device and reaction activation key
2) Urine cups with dip card

{2}

3

# Wondfo Methamphetamine Urine Test:

Two Different Formats:

1) Urine cups with built in test device and reaction activation key
2) Urine cups with dip card

Wondfo Cocaine and methamphetamine urine DOA test kits contain 25 tests (urine cups with built in test device, reaction activation key/ urine cups with dip card) per kit. Each kit contains 25 security sealed labels and a leaflet with instructions for use. For over the counter test kits, the following are contained with each kit: 25 labeled vials for shipping a “preliminary” sample to be confirmed by a lab, 25 plastic transportation bags, 25 mailing boxes, and 25 personal identification numbers.

Materials required but not provided: Timer, external urine controls

## J. Substantial Equivalence Information:

1. Predicate Device Name: Acon Laboratories, Inc. One Step Drug Screen Test
2. Predicate 510(k) Number(s): k020771

|  Similarities and Differences  |   |   |   |
| --- | --- | --- | --- |
|   |   | Candidate Devices: Wondfo Cocaine Urine Test and Wondfo Methamphetamine Urine Test (k112071) | Predicate Devices: Acon Laboratories, Inc. One Step Drug Screen Test (k020771)  |
|  Indication for use/ Intended Use |   | Qualitative detection of drugs-of- abuse in urine | Same  |
|  Intended Users |   | Prescription and Over the Counter Use. | Prescription Use  |
|  Specimen |   | Urine | Same  |
|  Methodology |   | Competitive binding, lateral flow immunochromatographic assay based on the principle of antigen antibody immunochemistry | Same  |
|  Type of Test |   | Immunoassay | Same  |
|  Device Design/ Performance | Positive Result | A rose-pink band in the control region | Same  |
|   |  |   |   |

{3}

|   |  | A rose-pink band visible in the control region and the test region | Same  |
| --- | --- | --- | --- |
|   |  Negative result  |   |   |
|   |  |   |   |
|   |  |   |   |
|   |  Detection reagent  |   |   |
|  Accuracy Assessment | Ovalbumin Conjugate
Anti-mouse IgG
Polyclonal antibody
(control line reagent) | Same  |   |
|  Results |   | Qualitative | Same  |
|  Cut-off |   | Cocaine 300 ng/mL
Methamphetamine 1000 ng/mL | Same  |
|  Configurations |   | Cup, dip card | Card, dip card with an integrated cup  |
|  Read time |   | 5 minutes | Same  |
|  Storage |   | 4 – 30°C | Same  |

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

None were referenced.

L. Test Principle:

Wondfo Methamphetamine and Cocaine Urine Tests are one-step lateral flow immunoassays containing a conjugate pad with colloidal gold with anti-drug antibodies, a nitrocellulose membrane, with a test line (T) and a control line (C). The T line is coated with drug antigen bound to duck egg protein and the C line is coated with goat anti-mouse IgG polyclonal antibodies. The test is a competitive binding immunoassay in which drugs and drug metabolites in a urine sample compete with immobilized drug conjugate for limited labeled antibody binding sites. When a sufficient amount of sample is applied, the sample migrates through the test device by capillary action. If the concentration of drug is below the cutoff level, the anti-drug antibodies in the colloidal gold particles will bind to the drug antigens coated in the test zone producing a band which indicates a negative result. If the drug concentration is at the cutoff level or higher no band will form in the test zone (test line T) indicating a preliminary positive. A band should form in the control region regardless of the presence of drug or metabolite in the sample.

M. Performance Characteristics (if/when applicable):

1. Analytical performance:

a. Precision/Reproducibility:

{4}

The precision study was conducted by three operators. Three different lots were tested for cocaine and methamphetamine using 12 devices/ lot at each control level of negative, -75%, -50%, -25%, cut-off, +25%, +50%, +75%, and +100% of the cut-off. Samples were prepared, concentrations of each sample confirmed by GC/MS, and then each sample was divided into 300 aliquots. The 300 sample aliquots were divided into 12 sets of 25 for each test format (cup/dipcard). The study was conducted over a 25 day period and ran 3 batches of each test format (cup/dipcard) in 2 runs/day. Each device was tested and interpreted by the same operator. Summaries are presented in the following tables:

The results summary is below:

Cocaine:

A. Cup Format

|  Result
COC | -100% cut off | -75% cut off | -50% cut off | -25% Cut off | Cut off | +25% cut off | +50% cut off | +75% cut off | +100% cut off  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|  LOT W1060901CU | 50-/0+ | 50-/0+ | 50-/0+ | 50-/0+ | 45+/5- | 50+/0- | 50+/0- | 50+/0- | 50+/0-  |
|  LOT W1060902CU | 50-/0+ | 50-/0+ | 50-/0+ | 50-/0+ | 45+/5- | 50+/0- | 50+/0- | 50+/0- | 50+/0-  |
|  LOT W1060903CU | 50-/0+ | 50-/0+ | 50-/0+ | 50-/0+ | 45+/5- | 50+/0- | 50+/0- | 50+/0- | 50+/0-  |

B. Dip card Format

|  Result
COC | -100% cut off | -75% Cut off | -50% cut off | -25% cut off | cut off | +25% cut off | +50% cut off | +75% Cut off | +100% cut off  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|  LOT W1060901P | 50-/0+ | 50-/0+ | 50-/0+ | 50-/0+ | 44+/6- | 50+/0- | 50+/0- | 50+/0- | 50+/0-  |
|  LOT W1060902P | 50-/0+ | 50-/0+ | 50-/0+ | 50-/0+ | 45+/5- | 50+/0- | 50+/0- | 50+/0- | 50+/0-  |
|  LOT W1060903P | 50-/0+ | 50-/0+ | 50-/0+ | 50-/0+ | 45+/5- | 50+/0- | 50+/0- | 50+/0- | 50+/0-  |

Methamphetamine:

A. Cup Format

|  Result
MET | -100% cut off | -75% cut off | -50% cut off | -25% Cut off | cut off | +25% cut off | +50% cut off | +75% cut off | +100% cut off  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|  LOT W1160901CU | 50-/0+ | 50-/0+ | 50-/0+ | 50-/0+ | 46+/4- | 50+/0- | 50+/0- | 50+/0- | 50+/0-  |

{5}

|  Result MET | -100% cut off | -75% cut off | -50% cut off | -25% Cut off | cut off | +25% cut off | +50% cut off | +75% cut off | +100% cut off  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|  LOT W1160902CU | 50-/0+ | 50-/0+ | 50-/0+ | 50-/0+ | 45+/5- | 50+/0- | 50+/0- | 50+/0- | 50+/0-  |
|  LOT W1160903CU | 50-/0+ | 50-/0+ | 50-/0+ | 50-/0+ | 45+/5- | 50+/0- | 50+/0- | 50+/0- | 50+/0-  |

B. Dip card Format

|  Result MET | -100% cut off | -75% cut off | -50% cut off | -25% cut off | cut off | +25% cut off | +50% cut off | +75% cut off | +100% cut off  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|  LOT W1160901P | 50-/0+ | 50-/0+ | 50-/0+ | 50-/0+ | 45+/5- | 50+/0- | 50+/0- | 50+/0- | 50+/0-  |
|  LOT W1160902P | 50-/0+ | 50-/0+ | 50-/0+ | 50-/0+ | 44+/6- | 50+/0- | 50+/0- | 50+/0- | 50+/0-  |
|  LOT W1160903P | 50-/0+ | 50-/0+ | 50-/0+ | 50-/0+ | 46+/4- | 50+/0- | 50+/0- | 50+/0- | 50+/0-  |

b. Linearity/assay reportable range:

Not applicable, the assay is intended for qualitative use.

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

This device has internal process controls. A colored line appearing in the control region confirms sufficient sample volume and adequate membrane wicking. Users are informed that the test is invalid if a line fails to appear in the control region.

Control standards are not supplied with this device; however it is good laboratory practice to confirm the test procedure and to verify proper test performance. Users should follow all applicable guidelines for testing QC materials.

Stability:

Accelerated stability and real time stability tests were performed on three batches of cups and dip card strips for the Wondfo Methamphetamine and Cocaine Urine tests. Accelerated stability and real time stability studies were performed and the results support Wondfo's claimed shelf life of 23 months at  $4^{\circ}\mathrm{C}$  and  $30^{\circ}\mathrm{C}$  for the cocaine urine tests and a shelf life of 24 months at  $4^{\circ}\mathrm{C}$  and  $30^{\circ}\mathrm{C}$  for the methamphetamine urine tests.

d. Detection limit:

Analytical performance of the device around the cutoff is described in

{6}

Section f. (Assay cut-off) below.

e. Analytical specificity:

To evaluate specificity of the urine cocaine and methamphetamine urine devices, three batches of urine samples were tested by taking 30 negative urine samples and spiking these samples with three different analyte concentration levels. Two different groups of operators were assigned to test blinded urine samples (three operators tested the cup format and three operators tested the dip stick format). Percent cross reactivity of a compound was calculated by dividing the cutoff concentration by the minimum concentration required to obtain a positive result and multiplying by 100%. Summary of the results are as follows:

Cocaine

|  COC(Cocaine) (Benzoylecgonine, Cutoff=300ng/mL) | Result Positive at 300 ng/mL | % Cross-Reactivity 100%  |
| --- | --- | --- |
|  Cocaine HCl | Positive at 750 ng/mL | 40%  |
|  Cocaethylene | Positive at 12,500 ng/mL | 2.4%  |
|  Ecgonine | Positive at 32,000 ng/mL | <1%  |

Met:

|  MET(Methamphetamine) (D(+)-Methamphetamine, Cutoff=1000 ng/mL) | Result Positive at 1,000 ng/mL | % Cross-Reactivity 100%  |
| --- | --- | --- |
|  D-Amphetamine | Positive at 50,000 ng/mL | 2%  |
|  Chloroquine | Positive at 50,000 ng/mL | 2%  |
|  (+/-)-Ephedrine | Positive at 50,000 ng/mL | 2%  |
|  (-)-Methamphetamine | Positive at 25,000 ng/mL | 4%  |
|  (+/-)3,4-methylenedioxumethamphetamine(MDMA) | Positive at 2,000 ng/mL | 50%  |
|  β-Phenylethylamine | Positive at 50,000 ng/mL | 2%  |
|  Trimethobenzamide | Positive at 10,000 ng/mL | 10%  |

Interference Studies:

Interference studies were performed using the cup and dipcard tests using urine controls at +/-25% of each analyte cut-off concentration. Potential interferences to the Wondfo cocaine and methamphetamine urine cup and dipcard tests were evaluated by adding various drugs, drug metabolites, and other compounds (structurally unrelated and endogenous compounds) that are commonly found in the urine which may interfere with testing results. The following compounds were found not to cross react when tested at concentrations of 100 µg/mL.

Cocaine:

{7}

|  Cortisone | Methadone | Quinidine |   |
| --- | --- | --- | --- |
|  Cortinine | Methoxyphenamine | Quinine |   |
|  Acetylthiophen | Dioxyn | Naltrexone | Temazepam  |
|  Acetophenetidin | (±)-3,4-Methylene | Naproline | Tetracycline  |
|  N-Deethylpentanamide | hydrochloride(±)-3,4-Dioxytoluene | Niacinamide | Tetrahydrocortisone, 3-Acetate  |
|  Acetylsalicylic acid | Dioxymethamphetamine | Salicylic acid | Tetrahydrocortisone, 3-(β-D-glucuronide)  |
|  Deoxypropoxyphen | Fluoropyrimine | Nifedipine | Tetrahydrozoline  |
|  Amitryptyline | Morphine, 3-β-D | Norebendital | Tetrabenzyl  |
|  Rinobarbital | (-) - 1-Ephedrine | Norethindrone | Thebaine  |
|  Rinobarbital | Morphine Sulfate | D-Norpropoxyphene | Thiamine  |
|  Rinofen | Nalidixic acid | Sulfamethazine | Thioridazine  |
|  Riflupin | Naloxymaminobenzoate | Dilindapamine | DL-Tyrosine  |
|  L-Ascorbic acid | Fenoprofen | Oxalic acid | Tolbutamide  |
|  DL-Amphetamine Sulfate | Furosemide | Oxazepam | Triamterene  |
|  Apomorphine | Gentisic acid | Oxolinic acid | Trifluoperazine  |
|  Aspartame | Hemoglobin | Oxycodone | Trimethoprim  |
|  Atropine | Hydralazine | Oxymetazoline | Trimipramine  |
|  Benzilic acid | Hydrochlorothiazide | Papaverine | Tryptamine  |
|  Benzoic acid | Hydrocodone | Penicillin-G | DL-Tryptophan  |
|  Benzphetamine | Hydrocortisone | Pentobarbital | Tyramine  |
|  Bilirubin | O-Hydroxyhippuric acid | Perphenazine | Uric acid  |
|  (±)-Brompheniramine | p-Hydroxymethamphetamine | Phencyclidine | Verapamil  |
|  Caffeine | 3-Hydroxytyramine | Phenelzine | Zomepirac  |
|  Cannabidiol | Ibuprofen | Phenobarbital |   |
|  Cannabinol | Imipramine | Phentermine |   |
|  Chloralhydrate | Iproniazid | L-Phenylephrine |   |
|  Chloramphenicol | (±) - Isoproterenol | β-Phenylethylamine |   |
|  Chlordiazepoxide | Isoxsuprine | Phenylpropanolamine |   |
|  Chlorothiazide | Ketamine | Prednisolone |   |
|  (±)-Chlorpheniramine | Ketoprofen | Prednisone |   |
|  Chlorpromazine | Labetalol | Procaine |   |
|  Chlorquine | Levorphanol | Promazine |   |
|  Cholesterol | Loperamide | Promethazine |   |
|  Clomipramine | Maprotiline | DL-Propranolol |   |
|  Clonidine | Meperidine | D-Propoxyphene |   |
|  Codeine | Meprobamate | D-Pseudoephedrine |   |

8

{8}

Methamphetamine

|  Acetamidophen | Estrone-3-sulfate | Noroxymorphone | Thioridazine  |
| --- | --- | --- | --- |
|  Acetophenetidin | Ethyl-p-aminobenzoate | D-Norpropoxyphene | Tolbutamine  |
|  N-Acetylprocainamide | Fenoprofen | Noscapine | Triamterene  |
|  Acetylsalicylate | Furosemide | Nylidrin | Trifluoperazine  |
|  Aminopyrine | Gentisic acid | D,L-Octopamine | Trimethoprim  |
|  Amitryptyline | Glucuronide | Oxalic acid | Trimipramine  |
|  Amobarbital | Glutethimide | Oxazepam | D, L-Tryptophan  |
|  Amoxicillin | Guaifenesin | Oxolinic acid | Tyramine  |
|  Ampicillin | Hippuric acid | Oxycodone | D, L-Tyrosine  |
|  Apomorphine | Hydralazine | Oxymetazoline | Uric acid  |
|  Aspartame | Hydrochlorothiazide | Papaverine | Verapamil  |
|  Atropine | Hydrocodone | Penicillin-G | Zomepirac  |
|  Benzilic acid | Hydrocortisone | Pentazocine |   |
|  Benzoic acid | O-Hydroxyhippuric acid | Pentobarbital |   |
|  Benzoylecgonine | 3-Hydroxytyramine | Perphenazine |   |
|  Butabartital | Ibuprofen | Phencyclidine |   |
|  Cannabidiol | Imipramine | Phenelzine |   |
|  Chloralhydrate | (-) Isoproterenol | Phenobarbital |   |
|  Chloramphenicol | Isoxsuprine | Prednisolone |   |
|  Chlordiazepoxide | Ketamine | Phenylpropanolamine |   |
|  Chlorothiazide | Ketoprofen | Prednisone |   |
|  Chlorpromazine | Labetalol | Procaine |   |
|  Cholesterol | Levorphanol | Promazine |   |
|  Clomipramine | Loperamide | Promethazine |   |
|  Clonidine | Loxapine succinate | D,L-Propanolol |   |
|  Cocaine hydrochloride | Maprotiline | D-Propoxyphene |   |
|  Codeine | Meperidine | D-Pseudoephedrine |   |
|  Cortisone | Meprobamate | Quinidine |   |
|  (-) Cotinine | Methadone | Quinine |   |
|  Creatinine | Methaqualone | Ranitidine |   |
|  Deoxycorticosterone | Methylphenidal | Salicylic acid |   |
|  Dextromethorphan | Methyprylon | Secobarbital |   |
|  Diazepam | Morphine-3-β-Dglucuronide | Serotonin (5-Hydroxytyramine) |   |
|  Diclofenac | Nalidixic acid | Sulfamethazine |   |
|  Diflunisal | Nalorphine | Sulindac |   |

9

{9}

|  Digoxin | Naloxone | Temazepam |   |
| --- | --- | --- | --- |
|  Diphenhydramine | Naltrexone | Tetracycline |   |
|  Doxylamine | Naproxen | Tetrahydrocortisone, 3-Acetate |   |
|  Ecgonine hydrochloride | Niacinamide | Tetrahydrocortisone 3 (β-D glucuronide) |   |
|  Ecgonine methyl ester | Nifedipine | Tetrahydrozoline |   |
|  Erythromycin | Norcodein | Thebaine |   |
|  β-Estradiol | Norethindrone | Thiamine |   |

pH:

The pH of an aliquoted negative urine pool was adjusted to pH 4, pH 5, pH 6, pH 7, pH 8, or pH 9 was spiked with +/- 25% of the cut-off concentration of benzoylecgonine and D(+) – Methamphetamine. Each was individually tested using three batches of strips and three batches of the cup format. The spiked, pH-adjusted urine was tested in triplicate. Varying the pH did not affect the accuracy of each test format (dipcard and cup).

Specific Gravity:

Twelve drug-free urine samples with specific gravities (1.000-1.035) and spiked with +/- 25% of the cut-off concentration of benzoylecgonine and D (+) – Methamphetamine using three batches of strips and three batches of the cup format. The spiked urine samples were tested in triplicate. The results show that varying the specific gravity does not affect the accuracy of each test format (dipcard and cup).

f. Assay cut-off:

The assay cut off established by collecting 25 clinical urine samples containing +/- 50% of the cocaine cutoff of 300 ng/ml and 25 clinical urine samples containing +/- 50% of the methamphetamine cutoff of 1000 ng/mL. Additionally, 125 drug-free clinical urine samples spiked with cocaine and 125 drug-free clinical urine samples spiked with methamphetamine were both diluted from the International Drug Standard (Sigma) to concentrations: -50%, -25%, cutoff, +25%, and +50% of the cocaine cutoff 300 ng/mL and methamphetamine cutoff 1000 ng/mL. The clinical urine samples were collected from the Shenzhen Drug Addiction Recovery Center and drug concentrations were confirmed by GC/MS. Results were read by three laboratory assistants with relevant experience. There cutoff studies were performed by two separate groups of operators (one for the dipcard format and one for the cup format). Three operators in each group performed the readings and they were blinded to the samples. Each result was confirmed by two other assistants. The results of the study are as follows:

{10}

Cocaine

a. Cup Format:

|  Concentration (ng/mL) | Cut-off range | n | Batch1 |   | Batch2 |   | Batch3 |   | Total  |   |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|   |   |   | - | + | - | + | - | + | - | +  |
|  150 | -50% cutoff | 30 | 30 | 0 | 30 | 0 | 30 | 0 | 90 | 0  |
|  225 | -25% cutoff | 30 | 30 | 0 | 30 | 0 | 30 | 0 | 90 | 0  |
|  300 | Cutoff | 30 | 3 | 27 | 2 | 28 | 3 | 27 | 8 | 82  |
|  375 | +25% cutoff | 30 | 0 | 30 | 0 | 30 | 0 | 30 | 0 | 90  |
|  450 | +50% cutoff | 30 | 0 | 30 | 0 | 30 | 0 | 30 | 0 | 90  |

b. DipCard Format

|  Concentration (ng/mL) | Cut-off range | n | Batch1 |   | Batch2 |   | Batch3 |   | Total  |   |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|   |   |   | - | + | - | + | - | + | - | +  |
|  150 | -50% cutoff | 30 | 30 | 0 | 30 | 0 | 30 | 0 | 90 | 0  |
|  225 | -25% cutoff | 30 | 30 | 0 | 30 | 0 | 30 | 0 | 90 | 0  |
|  300 | Cutoff | 30 | 3 | 27 | 3 | 27 | 3 | 27 | 9 | 81  |
|  375 | +25% cutoff | 30 | 0 | 30 | 0 | 30 | 0 | 30 | 0 | 90  |
|  450 | +50% cutoff | 30 | 0 | 30 | 0 | 30 | 0 | 30 | 0 | 90  |

Methamphetamine

a. Cup Format

|  Concentration (ng/mL) | Cut-off range | n | Batch1 |   | Batch2 |   | Batch3 |   | Total  |   |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|   |   |   | - | + | - | + | - | + | - | +  |
|  500 | -50% cutoff | 30 | 30 | 0 | 30 | 0 | 30 | 0 | 90 | 0  |
|  750 | -25% cutoff | 30 | 30 | 0 | 30 | 0 | 30 | 0 | 90 | 0  |
|  1000 | Cutoff | 30 | 3 | 27 | 3 | 27 | 2 | 28 | 8 | 82  |
|  1250 | +25% cutoff | 30 | 0 | 30 | 0 | 30 | 0 | 30 | 0 | 90  |

{11}

b. DipCard Format

|  Concentration (ng/mL) | Cut-off range | n | Batch1 |   | Batch2 |   | Batch3 |   | Total  |   |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|   |   |   | - | + | - | + | - | + | - | +  |
|  500 | -50% cutoff | 30 | 30 | 0 | 30 | 0 | 30 | 0 | 90 | 0  |
|  750 | -25% cutoff | 30 | 30 | 0 | 30 | 0 | 30 | 0 | 90 | 0  |
|  1000 | Cutoff | 30 | 4 | 26 | 5 | 25 | 2 | 28 | 11 | 79  |
|  1250 | +25% cutoff | 30 | 0 | 30 | 0 | 30 | 0 | 30 | 0 | 90  |
|  1500 | +50% cutoff | 30 | 0 | 30 | 0 | 30 | 0 | 30 | 0 | 90  |

The cut-off values were determined to be:

|  Test | Calibrator | Cut-off (ng/mL)  |
| --- | --- | --- |
|  Cocaine | Benzoylecgonine | 300  |
|  Methamphetamine | D-Methamphetamine | 1,000  |

# 2. Comparison studies:

a. Method comparison with predicate device:

Performance of the Wondfo Cocaine and Methamphetamine Urine Tests (dipcard and cup formats) were established by comparing 80 samples (40 positive and 40 negative) of each analyte against GC/MS. Ten of the 80 samples came from drug-free urine samples. Each result was read by three laboratory assistants and a lay person. All urine samples were collected at the Shenzhen Drug Addiction Recovery Center. A summary of results comparing the results of the lay person to the experienced person are as follows:

# Cocaine:

Cup Format:

|  Wondfo Device Result | Drug-Free urine | <-50% of the cut-off | Near cutoff (Between -50% and | Cut-off to +50% of the cut-off | >+ 50% of the cut-off  |
| --- | --- | --- | --- | --- | --- |
|   |  |  | the cut-off |  |   |
|  500 | +50% cutoff | 30 | 30 | 0 | 30  |
|  750 | +25% cutoff | 30 | 30 | 0 | 30  |
|  1000 | Cutoff | 30 | 4 | 26 | 5  |
|  1250 | +25% cutoff | 30 | 0 | 30 | 0  |
|  1500 | +50% cutoff | 30 | 0 | 30 | 0  |

{12}

|   |   |  |  | cutoff) |  |   |
| --- | --- | --- | --- | --- | --- | --- |
|  Viewer A | + | 0 | 0 | 1 | 11 | 29  |
|   |  - | 10 | 10 | 19 | 0 | 0  |
|  Viewer B | + | 0 | 0 | 2 | 11 | 29  |
|   |  - | 10 | 10 | 18 | 0 | 0  |
|  Viewer C | + | 0 | 0 | 2 | 11 | 29  |
|   |  - | 10 | 10 | 18 | 0 | 0  |
|  Lay Person | + | 0 | 0 | 2 | 11 | 29  |
|   |  - | 10 | 10 | 18 | 0 | 0  |

Dipcard Format:

|  Wondfo Device Result |   | Drug-Free urine | <-50% of the cut-off | Near cutoff (Between -50% and cutoff) | Cut-off to +50% of the cut-off | >+ 50% of the cut-off  |
| --- | --- | --- | --- | --- | --- | --- |
|  Viewer A | + | 0 | 0 | 2 | 11 | 29  |
|   |  - | 10 | 10 | 18 | 0 | 0  |
|  Viewer B | + | 0 | 0 | 1 | 11 | 29  |
|   |  - | 10 | 10 | 19 | 0 | 0  |
|  Viewer C | + | 0 | 0 | 2 | 11 | 29  |
|   |  - | 10 | 10 | 18 | 0 | 0  |
|  Lay Person | + | 0 | 0 | 3 | 11 | 29  |
|   |  - | 10 | 10 | 17 | 0 | 0  |

# Methamphetamine:

Cup Format:

|  Wondfo Device Result |   | Drug-Free urine | <-50% of the cut-off | Near cutoff (Between -50% and cutoff) | Cut-off to +50% of the cut-off | >+ 50% of the cut-off  |
| --- | --- | --- | --- | --- | --- | --- |
|  Viewer A | + | 0 | 0 | 1 | 20 | 20  |
|   |  - | 10 | 16 | 13 | 0 | 0  |
|  Viewer B | + | 0 | 0 | 2 | 20 | 20  |
|   |  - | 10 | 16 | 12 | 0 | 0  |
|  Viewer C | + | 0 | 0 | 1 | 20 | 20  |
|   |  - | 10 | 16 | 13 | 0 | 0  |
|  Lay Person | + | 0 | 0 | 3 | 20 | 20  |
|   |  - | 10 | 16 | 11 | 0 | 0  |

{13}

Dipcard Format:

|  Wondfo Device Result |   | Drug-Free urine | <-50% of the cut-off | Near cutoff (Between -50% and cutoff) | Cut-off to +50% of the cut-off | >+ 50% of the cut-off  |
| --- | --- | --- | --- | --- | --- | --- |
|  Viewer A | + | 0 | 0 | 1 | 20 | 20  |
|   |  - | 10 | 16 | 13 | 0 | 0  |
|  Viewer B | + | 0 | 0 | 2 | 20 | 20  |
|   |  - | 10 | 16 | 12 | 0 | 0  |
|  Viewer C | + | 0 | 0 | 2 | 20 | 20  |
|   |  - | 10 | 16 | 12 | 0 | 0  |
|  Lay Person | + | 0 | 0 | 2 | 20 | 20  |
|   |  - | 10 | 16 | 12 | 0 | 0  |

A summary of discordant results are as follows:

# Cocaine:

Cup Format:

|  Viewer | Sample Number | GC/MS result | Viewer Result  |
| --- | --- | --- | --- |
|  Viewer A | COC 209 | 212 | +  |
|  Viewer B | COC C35 | 222 | +  |
|  Viewer B | COC 219 | 241 | +  |
|  Viewer C | COC 210 | 292 | +  |
|  Viewer C | COC 219 | 241 | +  |
|  Lay person | COCC35 | 222 | +  |
|  Lay person | COC 219 | 241 | +  |

Dipcard Format:

|  Viewer | Sample Number | GC/MS result | Viewer Result  |
| --- | --- | --- | --- |
|  Viewer A | COC 209 | 212 | +  |
|  Viewer A | COC C35 | 222 | +  |
|  Viewer B | COC 210 | 292 | +  |
|  Viewer C | COC 219 | 241 | +  |
|  Viewer C | COC C35 | 222 | +  |
|  Lay person | COC C35 | 222 | +  |
|  Lay person | COC 210 | 292 | +  |
|  Lay person | COC 219 | 241 | +  |

{14}

# Methamphetamine:

Cup Format:

|  Viewer | Sample Number | GC/MS result | Viewer Result  |
| --- | --- | --- | --- |
|  Viewer A | METC92 | 914 | +  |
|  Viewer B | METC34 | 819 | +  |
|  Viewer B | METC92 | 914 | +  |
|  Viewer C | METC34 | 819 | +  |
|  Lay person | METC34 | 819 | +  |
|  Lay person | METC92 | 914 | +  |
|  Lay person | METC94 | 986 | +  |

Dipcard Format:

|  Viewer | Sample Number | GC/MS result | Viewer Result  |
| --- | --- | --- | --- |
|  Viewer A | METC34 | 819 | +  |
|  Viewer B | METC34 | 819 | +  |
|  Viewer B | METC92 | 914 | +  |
|  Viewer C | METC92 | 914 | +  |
|  Viewer C | METC94 | 986 | +  |
|  Lay person | METC92 | 914 | +  |
|  Lay person | METC94 | 986 | +  |

The results indicate a similar positive, negative, and overall agreement rates for both cocaine and methamphetamine using the cup and dipcard formats.

The overall agreement between the Wondfo devices and GC/MS is represented in the following table:

The agreement between Wondfo devices and GC/MS method

|  % Agreement | COC (cup) | COC (Dipcard) | MET (Cup) | MET (Dipcard)  |
| --- | --- | --- | --- | --- |
|  Positive | 100% | 100% | 100% | 100%  |
|  Negative | 95.8% | 95.8% | 96.7% | 95.8%  |
|  Total | 97.9% | 97.9% | 98.4% | 97.9%  |

The agreement between lay person and experience viewer:

|  % Agreement | COC (cup) | COC (Dipcard) | MET (Cup) | MET (Dipcard)  |
| --- | --- | --- | --- | --- |
|  Positive | 100% | 100% | 100% | 100%  |
|  Negative | 99.2% | 96.6% | 95.6% | 99.2%  |
|  Total | 99.6% | 98.3% | 97.8% | 99.6%  |

b. Lay-User Study:

A lay-user study was performed to assess the suitability of the device for home use. Six drug-free urine sample pools were spiked with +75%, +50%, +25%, -25%, -50%, and -75% of the cutoff for cocaine and

{15}

methamphetamine. Additionally, a negative urine pool with no drug was tested. The six spiked urine samples and the negative urine pool concentrations were confirmed by GC/MS and aliquoted into 40 individual containers per concentration (n=280 aliquots, 20 aliquots per concentration per test format). Testing was performed at three sites by 140 blinded consumers divided between three sites (140 lay-users for the cup format and 140 lay-users for the dipcard format). The lay users were chosen from likely intended users at the Shenzhen Drug Addiction Recovery Center, Guangzhou Red Cross Hospital, and Guangzhou Mental Hospital. Each participant received the package insert, 1 blinded sample, and either a cup or dipcard test format. The lay persons test result was compared to the GC/MS result to demonstrate accuracy by lay-users. The following are the results of the lay-user study:

## Cocaine:

Comparison between GC/MS and lay person results for Cup format

|  % of Cutoff | Number of samples | Benzoylecgonine Concentration by GC/MS (ng/mL) | Lay person results |   | The percentage of correct results (%)  |
| --- | --- | --- | --- | --- | --- |
|   |   |   |  No. of Positive | No. of Negative  |   |
|  -100% Cutoff | 20 | 0 | 0 | 20 | 100  |
|  -75% Cutoff | 20 | 71.5 | 0 | 20 | 100  |
|  -50% Cutoff | 20 | 169.4 | 0 | 20 | 100  |
|  -25% Cutoff | 20 | 208.5 | 2 | 18 | 90.0  |
|  +25% Cutoff | 20 | 398.6 | 19 | 1 | 95.0  |
|  +50% Cutoff | 20 | 475.6 | 20 | 0 | 100  |
|  +75% Cutoff | 20 | 508.3 | 20 | 0 | 100  |

Comparison between GC/MS and lay person results for Dip card format

|  % of Cutoff | Number of samples | Benzoylecgonine Concentration by GC/MS (ng/mL) | Lay person results |   | The percentage of correct results (%)  |
| --- | --- | --- | --- | --- | --- |
|   |   |   |  No. of Positive | No. of Negative  |   |
|  -100% Cutoff | 20 | 0 | 0 | 20 | 100  |
|  -75% Cutoff | 20 | 71.5 | 0 | 20 | 100  |
|  -50% Cutoff | 20 | 169.4 | 0 | 20 | 100  |
|  -25% Cutoff | 20 | 208.5 | 2 | 18 | 90.0  |
|  +25% Cutoff | 20 | 398.6 | 18 | 2 | 90.0  |
|  +50% Cutoff | 20 | 475.6 | 20 | 0 | 100  |
|  +75% Cutoff | 20 | 508.3 | 20 | 0 | 100  |

{16}

# Methamphetamine:

Comparison between GC/MS and lay person results for Cup format

|  % of Cutoff | Number of samples | D(+)-Methamphetamine Concentration by GC/MS (ng/mL) | Lay person results |   | The percentage of correct results (%)  |
| --- | --- | --- | --- | --- | --- |
|   |   |   |  No. of Positive | No. of Negative  |   |
|  -100% Cutoff | 20 | 0 | 0 | 20 | 100  |
|  -75% Cutoff | 20 | 269.5 | 0 | 20 | 100  |
|  -50% Cutoff | 20 | 542.6 | 0 | 20 | 100  |
|  -25% Cutoff | 20 | 700.1 | 2 | 18 | 90.0  |
|  +25% Cutoff | 20 | 1280.8 | 17 | 3 | 85.0  |
|  +50% Cutoff | 20 | 1582.4 | 20 | 0 | 100  |
|  +75% Cutoff | 20 | 1828.2 | 20 | 0 | 100  |

Comparison between GC/MS and lay person results for Dip card format

|  % of Cutoff | Number of samples | D(+)-Methamphetamine Concentration by GC/MS (ng/mL) | Lay person results |   | The percentage of correct results (%)  |
| --- | --- | --- | --- | --- | --- |
|   |   |   |  No. of Positive | No. of Negative  |   |
|  -100% Cutoff | 20 | 0 | 0 | 20 | 100  |
|  -75% Cutoff | 20 | 269.5 | 0 | 20 | 100  |
|  -50% Cutoff | 20 | 542.6 | 0 | 20 | 100  |
|  -25% Cutoff | 20 | 700.1 | 2 | 18 | 90.0  |
|  +25% Cutoff | 20 | 1280.8 | 19 | 1 | 95.0  |
|  +50% Cutoff | 20 | 1582.4 | 20 | 0 | 100  |
|  +75% Cutoff | 20 | 1828.2 | 20 | 0 | 100  |

The overall percent agreement between the Lay person and the GC/MS method:

|  % Agreement | COC (cup) | COC(dipcard) | MET (cup) | MET (dipcard)  |
| --- | --- | --- | --- | --- |
|  Total | 97.8% | 97.1% | 96.4% | 97.8%  |

c. Lay-User Questionnaires:

i. Cup Format:

Cocaine:

The participant's ages ranged from 23 to 62, and there were slightly more females than

{17}

males. There was a variety of occupational and educational backgrounds and two of the lay-users had used a home drug kit before. All participants understood the storage and expiration of the device and that the test could not be reused. They all understood that they could not insert and rotate the key until they were ready to test. They all read the test results at 5 minutes (none after 5 minutes) and all understood how to interpret the results.

Clarity of the package insert

|  Remarks | Very clear | Clear | Ambiguous | Very ambiguous  |
| --- | --- | --- | --- | --- |
|  Instruction for use | 64 | 76 | 0 | 0  |
|  Interpretation of results | 80 | 60 | 0 | 0  |

Clarity of test simplicity

|  Remarks | Very easy | Easy | Difficult | Very difficult  |
| --- | --- | --- | --- | --- |
|  Number | 86 | 52 | 2 | 0  |

Only two of the participants responded that the test was not easy to do.

# Methamphetamine:

The participant's ages ranged from 23 to 61, and there were slightly more females than males. There was a variety of occupational and educational backgrounds and two of the lay-users had used a home drug kit before. All participants understood the storage and expiration of the device and that the test could not be reused. They all understood that they could not insert and rotate the key until they were ready to test. They all read the test results at 5 minutes (none after 5 minutes) and all understood how to interpret the results.

Clarity of the package insert

|  Remarks | Very clear | Clear | Ambiguous | Very ambiguous  |
| --- | --- | --- | --- | --- |
|  Instruction for use | 69 | 71 | 0 | 0  |
|  Interpretation of results | 86 | 54 | 0 | 0  |

Clarity of test simplicity

|  Remarks | Very easy | Easy | Difficult | Very difficult  |
| --- | --- | --- | --- | --- |
|  Number | 92 | 48 | 0 | 0  |

None of the participants responded that the test was not easy to do.

ii. Dipcard Format:

# Cocaine:

{18}

The participant's ages ranged from 22 to 60, and there were slightly more males than females. There was a variety of occupational and educational backgrounds and none of the lay-users had used a home drug kit before. All participants understood the storage and expiration of the device and that the test could not be reused. They all understood that the dipcard couldn't be immersed in urine above the marker line and understood the storage and expiration of the device and that the test could not be reused. They all read the test results at 5 minutes (none after 5 minutes) and all understood how to interpret the results.

Clarity of the package insert

|  Remarks | Very clear | Clear | Ambiguous | Very ambiguous  |
| --- | --- | --- | --- | --- |
|  Instruction for use | 60 | 80 | 0 | 0  |
|  Interpretation of results | 74 | 66 | 0 | 0  |

Clarity of test simplicity

|  Remarks | Very easy | Easy | Difficult | Very difficult  |
| --- | --- | --- | --- | --- |
|  Number | 70 | 69 | 1 | 0  |

Only one of them responded that the test was not easy to do.

# Methamphetamine:

The participant's ages ranged from 22 to 67, and there were slightly more males than females. There was a variety of occupational and educational backgrounds and none of the lay-users had used a home drug kit before. All participants understood the storage and expiration of the device and that the test could not be reused. They all understood that the dipcard couldn't be immersed in urine above the marker line and understood the storage and expiration of the device and that the test could not be reused. They all read the test results at 5 minutes (none after 5 minutes) and all understood how to interpret the results.

Clarity of the package insert

|  Remarks | Very clear | Clear | Ambiguous | Very ambiguous  |
| --- | --- | --- | --- | --- |
|  Instruction for use | 67 | 73 | 0 | 0  |
|  Interpretation of results | 80 | 60 | 0 | 0  |

Clarity of test simplicity

|  Remarks | Very easy | Easy | Difficult | Very difficult  |
| --- | --- | --- | --- | --- |
|  Number | 69 | 69 | 2 | 0  |

Only two of them responded that the test was not easy to do.

Additionally, a Flesch-Kincaid reading analysis revealed that both package inserts had a reading grade level of 8.

{19}

c. Matrix comparison:
Not applicable; these devices are for use with urine only.

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.

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.

20

---

**Source:** [https://fda.innolitics.com/submissions/CH/subpart-d%E2%80%94clinical-toxicology-test-systems/DIO/K112071](https://fda.innolitics.com/submissions/CH/subpart-d%E2%80%94clinical-toxicology-test-systems/DIO/K112071)

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