(31 days)
The Immunalysis PCP Urine Enzyme Immunoassay is a homogeneous enzyme immunoassay with a cutoff of 25ng/mL. The assay is intended for use in laboratories for the qualitative and semi-quantitative analysis of PCP in human urine with automated clinical chemistry analyzers. This assay is calibrated against PCP. This in-vitro diagnostic device is for prescription use only.
The semi-quantitative mode is for purposes of enabling laboratories to determine an appropriate dilution of the specimen for confirmation by a confirmatory method such as Gas Chromatography/ Mass Spectrometry (GC-MS) or permitting laboratories to establish quality control procedures.
The Immunalysis PCP Urine Enzyme Immunoassay Kit provides only a preliminary analytical test result. A more specific alternate chemical method must be used in order to obtain a confirmed analytical result. GC-MS or Liquid Chromatography/Mass Spectrometry (LC/MS) is the preferred confirmatory method. Clinical consideration and professional judgment should be applied to any drug of abuse test result, particularly when preliminary positive results are used.
The Immunalysis Multi-Drug Calibrators are intended for in vitro diagnostic use for the calibration of assays for the analytes currently listed in the package insert: Benzoylecgonine, Morphine and PCP. The calibrators are designed for prescription use with immunoassays.
- The assay consists of antibody/ substrate reagent and enzyme conjugate reagent. The antibody/ substrate reagent includes recombinant antibodies to Phencyclidine. glucose-6-phosphate (G6P) and nicotinamide adenine dinucleotide (NAD) in Tris buffer with Sodium Azide as a preservative. The enzyme conjugate reagent includes phencyclidine derivative labeled with glucose-6-phosphate dehydrogenase (G6PDH) in Tris buffer with Sodium Azide as a preservative.
- All of the Immunalysis Multi-Drug Calibrators are liquid and ready to use. Each contains a known concentration of a specific drug analyte as a mixture. The negative calibrator is a processed, drug-free synthetic urine matrix with sodium azide as a preservative. The Level 1, 2, 3 and 4 calibrators are prepared by spiking known concentrations of drug analyte into the negative calibrator matrix. These five calibrators (negative, Level 1, 2, 3 and 4) are sold as individual bottles. The concentration of drug analyte in the corresponding calibrators are summarized as follows:
Table 1 Immunalysis Multi-Drug Calibrators
Analyte, Multi-Drug Calibrators, Level 1, Level 2, Level 3, Level 4
Benzoylecgonine, 150ng/mL, 300ng/mL, 500ng/mL, 1000ng/mL
Morphine, 100ng/mL, 300ng/mL, 500ng/mL, 1000ng/mL
PCP, 12.5ng/mL, 25ng/mL, 50ng/mL, 100ng/mL
Acceptance Criteria and Device Performance for Immunalysis PCP Urine Enzyme Immunoassay
This document describes the acceptance criteria and study results for the Immunalysis PCP Urine Enzyme Immunoassay, an in-vitro diagnostic device intended for the qualitative and semi-quantitative analysis of PCP in human urine. All reported testing used a Beckman Coulter AU 400e instrument unless otherwise specified.
1. Table of Acceptance Criteria & Reported Device Performance
| Study/Test | Acceptance Criteria | Reported Device Performance (Summary) |
|---|---|---|
| Qualitative Analysis (25 ng/mL cutoff) | Correct classification of samples at various concentrations around the cutoff. | At -100% to -25% of cutoff (0-19 ng/mL): 80/80 Negative results for each concentration. |
| At cutoff (25 ng/mL): 35 Negative, 45 Positive. | ||
| At +25% to +100% of cutoff (31-50 ng/mL): 80/80 Positive results for each concentration. | ||
| Semi-Quantitative Analysis (25 ng/mL cutoff) | Correct classification of samples at various concentrations around the cutoff. | At -100% to -25% of cutoff (0-19 ng/mL): 80/80 Negative results for each concentration. |
| At cutoff (25 ng/mL): 30 Negative, 50 Positive. | ||
| At +25% to +100% of cutoff (31-50 ng/mL): 80/80 Positive results for each concentration. | ||
| Specificity and Cross-Reactivity (Qualitative) | Correct classification (Positive result at specified concentration) and low cross-reactivity with structurally similar compounds. | PCP: 100% cross-reactivity. Other structurally similar compounds showed very low cross-reactivity (0.00250% to 0.71429%). |
| Specificity and Cross-Reactivity (Semi-Quantitative) | Correct classification and low cross-reactivity with structurally similar compounds, with mean values near the cutoff for tested compounds. | PCP: Mean Value 26.7 ng/mL, 100% cross-reactivity. Other structurally similar compounds showed very low cross-reactivity (0.00250% to 0.71429%), with mean values near the cutoff for concentrations where a positive result was obtained. |
| Interference (Structurally Non-Similar Compounds, Endogenous Compounds, pH, Specific Gravity) | Assay performance unaffected (correct classification) when potential interferents were spiked into drug-free urine containing target analyte at ±25% of cutoff. | All tested structurally non-similar compounds and endogenous compounds showed "No" interference, meaning the -25% cutoff samples were Negative and +25% cutoff samples were Positive. |
| No interference observed for pH values ranging from 3.0 to 11.0. | ||
| No interference observed for specific gravity values ranging from 1.000 to 1.030. | ||
| Interference (Boric Acid) | Assay performance unaffected. | Interference identified. For a 1% w/v concentration of Boric Acid, the -25% cutoff (19 ng/mL) sample was Negative (No interference), but the +25% cutoff (31 ng/mL) sample was also Negative (Yes interference). This indicates Boric Acid interferes with the assay. Limitations have been added to the labeling. |
| Linearity/Recovery | Acceptable recovery (%) across a range of expected concentrations. | Recovery ranged from 94.7% (at 10 ng/mL expected) to 111.9% (at 70 ng/mL expected). All reported recoveries were within acceptable ranges, typically 90-110%. |
| Method Comparison (Qualitative) | High agreement with LC/MS confirmation. | 100% agreement: 40 positive and 40 negative results matched LC/MS confirmation. |
| Method Comparison (Semi-Quantitative) | High agreement with LC/MS confirmation. | 100% agreement: 40 positive and 40 negative results matched LC/MS confirmation. |
| Calibrator Closed Vial Stability | Calibrator levels within specifications for a specified duration. | All calibrator levels (1, 2, 3, and 4) for PCP were within specifications for Day 0, 8, 16, 24, 32, and 40. Supported 12 months initial expiration dating. |
| Calibrator Open Vial Stability | Calibrator levels within specifications for a specified duration. | All calibrator levels (1, 2, 3, and 4) for PCP were within specifications for Day 0, 19, 26, 33, 41, and 60. Supported 60 days initial open vial expiration dating. |
2. Sample Size Used for the Test Set and Data Provenance
- Precision/Cutoff Characterization Study: 80 determinations for each of the 9 concentration levels, totaling 720 determinations.
- Specificity and Cross-Reactivity Study: Concentrations were tested to a level that would yield a positive result (equivalent to the cutoff). The specific number of determinations per compound is not explicitly stated but implied to be sufficient for result generation.
- Interference Study (Structurally Non-Similar Compounds, Endogenous Compounds, pH, Specific Gravity, Boric Acid): Not explicitly stated, but for each compound/parameter, measurements were taken at -25% and +25% of the cutoff concentration.
- Linearity/Recovery: Not explicitly stated, but 11 data points (expected concentrations) were used for the linearity curve.
- Method Comparison: 80 clinical urine samples (40 positive, 40 negative) were used.
- Calibrator Stability Studies: Data for Day 0, 8, 16, 24, 32, 40 (closed vial) and Day 0, 19, 26, 33, 41, 60 (open vial) for all 4 calibrator levels.
Data Provenance:
- Precision/Cutoff Characterization, Specificity, Interference, Linearity/Recovery: These studies appear to be laboratory-based experiments, likely conducted in the US (Immunalysis Corporation is based in Pomona, CA). The data is prospective as it was generated to evaluate the device.
- Method Comparison: "Unaltered, anonymous and discarded clinical urine samples obtained from clinical testing laboratories" were used. This indicates the data is retrospective, and likely from the US, given the company's location.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The document does not mention the use of human experts to establish ground truth for the test set.
4. Adjudication Method for the Test Set
Not applicable, as human experts were not used to establish ground truth.
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 assay for qualitative and semi-quantitative analysis of a substance in urine, not for interpretation by human readers.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
Yes, the studies described (Precision, Specificity, Interference, Linearity, Method Comparison, Calibrator performance) represent standalone performance of the Immunalysis PCP Urine Enzyme Immunoassay device. The device itself is an automated chemical analyzer-based test.
7. The Type of Ground Truth Used
- Precision/Cutoff Characterization, Specificity, Interference, Linearity/Recovery, Calibrator Stability: Ground truth was established by preparing samples with known, spiked concentrations of PCP or other compounds in drug-free urine.
- Method Comparison: Ground truth was established by confirmation with Gas Chromatography/Mass Spectrometry (GC-MS) or Liquid Chromatography/Mass Spectrometry (LC/MS), which are considered definitive analytical methods.
8. The Sample Size for the Training Set
This document describes a premarket notification for an immunoassay that operates based on established chemical reactions, not a machine learning or AI algorithm that requires a "training set" in the conventional sense. Therefore, the concept of a training set sample size is not applicable to this device.
9. How the Ground Truth for the Training Set Was Established
Not applicable, as there is no "training set" for this type of immunoassay.
N/A