(89 days)
ACON PPX One Step Propoxyphene Test Strip or ACON PPX One Step Propoxyphenc Test Device is a lateral flow chromatographic immunoassay test for the qualitative detection of Dpropoxyphene in human urine at a cut-off concentration of 300 ng/mL. It is a prescription assay intended for use by healthcare professionals including those at the point of care sites.
This assay provides only a preliminary analytical test result. A more specific alternate chemical method must be used in order to obtain a confirmed analytical result. Gas chromatography/mass spectrometry (GC/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 ACON PPX One Step Propoxyphene Test Strip and ACON PPX One Step Propoxyphene Test Device are competitive binding, lateral flow immunochromatographic assays for the qualitative screening of Propoxyphene in a urine sample. The test is based on the principle of antibody immunochemistry. It utilizes the mouse monoclonal antibody to selectively detect elevated levels of Propoxyphene and its metabolite in urine at a cutoff concentration of 300 ng/mL. These tests can be performed without the use of an instrument.
A drug-positive urine specimen will not generate a colored-line in the designated test region, while a negative urine specimen or a urine specimen containing Propoxyphene at the concentration below the cutoff level will generate a colored-line in the test region. To serve as a procedural control, a coloredline should always appear at the control region, indicating that proper volume of specimen has been added and membrane wicking has occurred.
Acceptance Criteria and Study for ACON PPX One Step Propoxyphene Test Strip/Device
1. Table of Acceptance Criteria and Reported Device Performance
The provided document does not explicitly state pre-defined acceptance criteria with numerical targets. Instead, it demonstrates "substantial equivalency" to an FDA-cleared predicate device. The performance is reported in terms of agreement with both the predicate device and Gas Chromatography/Mass Spectrometry (GC/MS).
| Performance Metric | Acceptance Criteria (Implied by Substantial Equivalence) | Reported Device Performance (ACON PPX One Step Propoxyphene Test Strip) | Reported Device Performance (ACON PPX One Step Propoxyphene Test Device) |
|---|---|---|---|
| Positive Agreement vs. Predicate Device | High agreement, approaching 100% | >99% (98% - 99% CI) | >99% (98% - 99% CI) |
| Negative Agreement vs. Predicate Device | High agreement, approaching 100% | >99% (98% - 99% CI) | >99% (98% - 99% CI) |
| Overall Agreement vs. Predicate Device | High agreement, approaching 100% | >99% (99% - 99% CI) | >99% (99% - 99% CI) |
| Agreement with GC/MS for Positive Results | Not explicitly stated, but expected to be high for confirmation | Implicitly demonstrated by overall high agreement with a device that is compared to GC/MS | Implicitly demonstrated by overall high agreement with a device that is compared to GC/MS |
| Agreement with GC/MS for Negative Results | Not explicitly stated, but expected to be high for confirmation | Implicitly demonstrated by overall high agreement with a device that is compared to GC/MS | Implicitly demonstrated by overall high agreement with a device that is compared to GC/MS |
Note: The confidence intervals provided (e.g., 98% - 99%) are described as "97.5% confidence interval" in the document, which might be a typo for a standard 95% CI. However, without further clarification, it's presented as stated. The ">99%" indicates that the observed agreement was 100%.
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: 314 clinical urine specimens.
- Approximately 10% of these specimens contained Propoxyphene concentrations between -25% and +25% of the 300 ng/mL cutoff.
- The agreement calculations (positive, negative, overall) were based on 157 positive and 157 negative results, summing to 314.
- Data Provenance: The document states "clinical urine specimens," implying human-derived samples. However, the country of origin and whether the data was retrospective or prospective are not specified.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
This type of diagnostic device (immunochromatographic assay for drug detection) typically does not rely on human "experts" in the traditional sense (e.g., radiologists interpreting images) for establishing ground truth in clinical validation. Instead, the ground truth for chemical analytes is established by a reference method.
- The ground truth in this study was primarily established by Gas Chromatography/Mass Spectrometry (GC/MS) analysis, which is considered the "gold standard" for confirmatory drug testing.
- The study also compared the device performance against "a FDA-cleared Propoxyphene test," which can be considered a strong predicate for comparison.
- Therefore, there were no human experts involved in establishing the ground truth, but rather analytical instruments and methodologies.
4. Adjudication Method for the Test Set
Since the ground truth was established by an objective analytical method (GC/MS), an adjudication method (like 2+1, 3+1 consensus among human readers) is not applicable in this context. The GC/MS results are considered definitive.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No. A MRMC comparative effectiveness study, which typically evaluates the performance of human readers with and without AI assistance, was not performed. This is a standalone diagnostic device that does not involve human interpretation in the same way imaging AI models do.
6. Standalone Performance Study
Yes. The described accuracy study conducted against GC/MS analysis serves as a standalone performance evaluation of the ACON PPX One Step Propoxyphene Test Strip and Device. The results indicate the device's ability to qualitatively detect Propoxyphene in urine.
7. Type of Ground Truth Used
The primary ground truth used was Gas Chromatography/Mass Spectrometry (GC/MS) analysis. The study also utilized comparison to an "FDA-cleared Propoxyphene test" as part of its validation.
8. Sample Size for the Training Set
The document is a 510(k) summary for a rapid immunochromatographic assay. This type of device does not typically involve a "training set" in the context of machine learning or AI models. The device's mechanism is based on established immunochemistry principles and monoclonal antibodies. Therefore, a training set sample size is not applicable or reported for this device.
9. How Ground Truth for the Training Set Was Established
As mentioned above, this device does not utilize a training set in the AI/machine learning sense. Therefore, the method for establishing ground truth for a training set is not applicable. The underlying principles (antibody sensitivity/specificity) are developed and optimized during the research and development phase of the assay, not through a "training set" of clinical data.
§ 862.3700 Propoxyphene test system.
(a)
Identification. A propoxyphene test system is a device intended to measure propoxyphene, a pain-relieving drug, in serum, plasma, and urine. Measurements obtained by this device are used in the diagnosis and treatment of propoxyphene use or overdose or in monitoring levels of propoxyphene to ensure appropriate therapy.(b)
Classification. Class II (special controls). A propoxyphene 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).