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The Alinity c Cocaine assay is a homogeneous enzyme immunoassay intended for the qualitative and/or semi-quantitative determination of benzoylecgonine (Cocaine Metabolite) in human urine at a cutoff concentration of either 150 ng/mL or 300 ng/mL on the Alinity c analyzer.

The semiquantitative application 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) are the preferred confirmatory method. Tests for cocaine metabolite cannot distinguish between abused drugs and certain prescribed medications.

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 Cocaine Metabolite Assay is a homogeneous enzyme immunoassay using ready-to-use liquid reagents. The assay uses a specific antibody, which can detect benzoylecgonine 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 samplefor a fixed amount of specific antibody binding sites. In the presence of free drug fromthe sample, the free drug occupies the antibody binding sites, allowing the drug-labeled G6PDH to interact with the substrate, resulting in enzyme activity. In the absence of drug from the sample, the specific antibody binds to the drug labeled with G6PDH and the enzyme activity is inhibited. This phenomenon creates a direct relationship between the drug concentration in the 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 mouse monoclonal anti-benzoylecgonine antibody, glucose-6- phosphate (G6P), and nicotinamide adenine dinucleotide (NAD) in Tris buffer with sodium azide as preservative.

Reagent E: Contains benzoylecgonine analog labeled with glucose-6-phosphate dehydrogenase (G6PDH) in HEPES buffer with sodium azide as preservative.

The provided text describes the analytical performance studies for the DRI Cocaine Metabolite Assay, an in vitro diagnostic device, rather than an AI-powered medical device requiring human-in-the-loop studies or expert consensus for ground truth. Therefore, many of the requested elements for AI/ML device studies (such as MRMC studies, number of experts for ground truth, adjudication methods, training set information) are not applicable to this submission.

However, I can extract information related to the acceptance criteria and performance of this in vitro diagnostic device.

Here's a breakdown based on the provided document:

Acceptance Criteria and Reported Device Performance

The acceptance criteria are implied by the results presented in the analytical performance studies. The device is expected to accurately categorize samples as negative or positive relative to defined cutoffs (150 ng/mL or 300 ng/mL) and demonstrate good precision, linearity, and minimal interference.

Table of Acceptance Criteria (Implied) and Reported Device Performance

Study Details (for an In Vitro Diagnostic Device)

1. Sample Size Used for the Test Set and Data Provenance:

   • Precision Study: For each cutoff (150 ng/mL and 300 ng/mL), samples were tested in replicates of 3, twice per day for 20 days, totaling n=120 for each of the 9 spiked concentrations (e.g., 0 ng/mL, 37.5 ng/mL, ... 300 ng/mL for 150 ng/mL cutoff). This is 9 concentrations * 120 determinations = 1080 determinations per cutoff for precision.
   • Spike Recovery: 25 replicates for each of two concentrations (below and above cutoff) for each cutoff level. 2 concentrations * 25 replicates = 50 replicates per cutoff.
   • Linearity: 9 intermediate levels and 2 end points (0 and 1032.2 ng/mL), each run in replicates of five. 11 levels * 5 replicates = 55 replicates.
   • Method Comparison (Accuracy): "At least one hundred patient samples" were analyzed by the device and compared to LC-MS/MS. The tables show results for a total of 101 samples for the 150 ng/mL cutoff (12 negative + 33 <50% + 5 Near Cutoff Negative + 5 Near Cutoff Positive + 46 High Positives = 101). A similar number would apply for the 300 ng/mL cutoff.
   • Specificity (Cross-Reactivity) and Interference: Varied number of spiked samples (low and high controls) for each of the numerous compounds tested. The exact sample size for each compound is not explicitly stated but implies sufficient testing to demonstrate the effect (or lack thereof) on the low and high controls.
   • Data Provenance: Not explicitly stated regarding country of origin. The studies are described as "retrospective" or "prospective" is not specified but given the nature of in vitro diagnostic analytical performance studies, they are typically laboratory-based studies using prepared or banked samples, which could be considered prospective (purposefully created) or using retrospective (previously collected) clinical samples. The "Method Comparison" section explicitly mentions "patient samples", suggesting clinical samples.

2. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts:

   • Not applicable as this is an in vitro diagnostic device for quantitative and qualitative determination of a specific analyte, not an AI/ML device requiring human expert annotation of images or complex data. The "ground truth" for method comparison studies is established by a well-accepted, highly sensitive and specific confirmatory method, in this case, Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS).

3. Adjudication Method:

   • Not applicable for this type of device. Discrepancies between the device and the reference method (LC-MS/MS) are reported and discussed (e.g., the 1 discordant result for 150 ng/mL cutoff, and 2 for 300 ng/mL cutoff in the method comparison).

4. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:

   • No. This is an in vitro diagnostic assay, not an AI-powered diagnostic imaging device that involves human reader interpretation. No human readers are involved in performing or interpreting the results of this chemical assay after the initial lab technician operates the Alinity c analyzer.

5. Standalone (Algorithm Only Without Human-in-the-Loop) Performance:

   • This is effectively a standalone device. The device (Alinity c Cocaine assay) generates a result (qualitative or semi-quantitative concentration) based on its chemical reactions and spectrophotometric measurements. The human "in the loop" would be the laboratory personnel operating the analyzer and reviewing the results, but the analytical performance described is of the device itself.

6. Type of Ground Truth Used:

   • Confirmatory Method: For accuracy and method comparison studies, the ground truth was established by Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS), which is considered a gold standard confirmatory method for drug testing.
   • Known Spiked Concentrations: For precision, spike recovery, linearity, specificity, interference, and specific gravity studies, the ground truth was established by preparing urine samples with known, precise concentrations of the analyte (Benzoylecgonine) or interfering substances.

7. Sample Size for the Training Set:

   • Not applicable. This is not an AI/ML device that undergoes a "training" phase on a specific dataset. Its performance is based on its electrochemical and optical principles.

8. How the Ground Truth for the Training Set Was Established:

   • Not applicable, as there is no "training set" in the context of an AI/ML model. The chemical and performance characteristics of the assay are intrinsic to its design and manufacturing.

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