(525 days)
The Acetaminophen assay is used for the quantitative determinophen in human serum or plasma on the ARCHITECT c Systems.
The Acetaminophen assay is to be used as an aid in the diagnosis and treatment of acetaminophen overdose toxicity.
The Acetaminophen assay is an enzymatic, spectrophotometric assay for the measurement of acetaminophen concentration in human serum and plasma. The assay consists two working reagents, an enzyme reagent and a color reagent.
The enzyme reagent contains aryl acylamidase, which cleaves the amide bond of acetaminophen, forming p-aminophenol which then reacts with the 2,5-dimethylphenol (contained the color reagent) in the presence of manganese. The product of that reaction causes increased absorbance at 660 nm which is directly proportional to the acetaminophen concentration in the sample.
Testing is performed on the ARCHITECT c8000 clinical chemistry analyzers in conjunction with a calibrator (510(k) exempt) which is provided separately.
The provided text describes a 510(k) premarket notification for an Acetaminophen assay (K202644). The document details various performance studies conducted to demonstrate the device's substantial equivalence to a legally marketed predicate device.
Here's an analysis of the acceptance criteria and study details based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Performance Metric | Acceptance Criteria (Stated or Implied) | Reported Device Performance |
|---|---|---|
| Precision (Within-Run %CV) | Not explicitly stated as acceptance criteria, but typically within acceptable laboratory limits for clinical assays. For example, for Control Level 1, %CV (0.9) is excellent; for Panel A, %CV (5.6) is higher but likely acceptable for low concentrations. | Control Level 1: Mean 15 µg/mL, SD 0.1, %CV 0.9 |
| Control Level 2: Mean 73 µg/mL, SD 0.5, %CV 0.6 | ||
| Control Level 3: Mean 227 µg/mL, SD 0.8, %CV 0.3 | ||
| Panel A: Mean 5 µg/mL, SD 0.3, %CV 5.6 | ||
| Panel B: Mean 51 µg/mL, SD 0.3, %CV 0.6 | ||
| Panel C: Mean 84 µg/mL, SD 0.4, %CV 0.4 | ||
| Panel D: Mean 278 µg/mL, SD 1.0, %CV 0.4 | ||
| Panel E: Mean 362 µg/mL, SD 1.6, %CV 0.4 | ||
| Precision (Within-Laboratory %CV) | Not explicitly stated as acceptance criteria, but typically within acceptable laboratory limits. | Control Level 1: SD 0.2, %CV 1.3 |
| Control Level 2: SD 0.6, %CV 0.8 | ||
| Control Level 3: SD 1.3, %CV 0.6 | ||
| Panel A: SD 0.5, %CV 9.1 | ||
| Panel B: SD 0.4, %CV 0.7 | ||
| Panel C: SD 0.6, %CV 0.7 | ||
| Panel D: SD 2.0, %CV 0.7 | ||
| Panel E: SD 2.6, %CV 0.7 | ||
| Reproducibility (%CV) | Not explicitly stated as acceptance criteria, but typically within acceptable laboratory limits. | Control 1: Mean 14 µg/mL, SD 0.5, %CV 3.2 |
| Control 2: Mean 68 µg/mL, SD 0.6, %CV 0.9 | ||
| Control 3: Mean 208 µg/mL, SD 1.6, %CV 0.8 | ||
| Panel: Mean 163 µg/mL, SD 1.2, %CV 0.7 | ||
| Limit of Blank (LoB) | Not explicitly stated, but should ideally be very low. | 0 µg/mL (0 µmol/L) |
| Limit of Detection (LoD) | The sponsor chose to use 1 µg/mL (7 µmol/L) for reporting purposes. | Scientific LoD: 0.2 µg/mL (1.3 µmol/L) |
| Reporting LoD: 1 µg/mL (7 µmol/L) | ||
| Limit of Quantitation (LoQ) | The sponsor chose to use 3 µg/mL (20 µmol/L) for reporting purposes. This is the lower end of the analytical measuring interval. | Scientific LoQ: 1.9 µg/mL (12.6 µmol/L) |
| Reporting LoQ (lower end of AMI): 3 µg/mL (20 µmol/L) | ||
| Linearity/Assay Range | Device demonstrated linearity across the range of 0 to 386 µg/mL, which spans the analytical measuring interval of 3 to 377 µg/mL. Implicit acceptance is that the assay is linear across its claimed analytical measuring interval. | Linear across 0 to 386 µg/mL. Analytical Measuring Interval: 3 to 377 µg/mL (20 to 2496 µmol/L). |
| Analytical Specificity (Interference) | Interference within ± 7.5% for acetaminophen samples > 20 µg/mL, OR | |
| within ± 1.50 µg/mL for acetaminophen samples 0.975 or >0.98), slope close to 1, and intercept close to 0. | Correlation Coefficient: 0.9993 | |
| Slope: 1.042 | ||
| Intercept: -0.034 | ||
| (Comparing 3.50 - 356.26 µg/mL (predicate) to 3.58 - 375.28 µg/mL (candidate)) | ||
| Matrix Comparison | Recovered within ± 7.5% for values ≥ 20 µg/mL, OR | |
| within ± 1.50 µg/mL for values |
§ 862.3030 Acetaminophen test system.
(a)
Identification. An acetaminophen test system is a device intended to measure acetaminophen, an analgestic and fever reducing drug, in serum. Measurements obtained by this device are used in the diagnosis and treatment of acetaminophen overdose.(b)
Classification. Class II.