Search Results

The Seradyn QMS® Topiramate assay is intended for the quantitative determination of topiramate in human serum or plasma on automated clinical chemistry analyzers.

The results obtained are used in the diagnosis and treatment of topiramate overdose and in monitoring levels of topiramate to help ensure appropriate therapy.

The Seradyn QMS® Topiramate assay is a homogeneous particle-enhanced turbidimetric immunoassay. The assay is based on competition between drug in the sample and drug coated onto a micronariticle for antibody binding sites of the topiramate antibody reagent. The topiramate-coated micropariticle peagent is rapidly agglutinated in the presence of the anti-topiramate antibody reagent and in the abserved of any competing drug in the sample. The rate of absorbance change is measured photometrically. When a smale containing topiramate is added, the agglutination reaction is partially inhibited, slowing down the rate of absorbance change. A concentration-dependent classic agglutination inhibition curve can be obtained with maximum rate of agglutination at the lowest topiramate concentration and the lowest agglutination rate at the highest topiramate concentration.

The assay consists of reagents R1: anti-topiramate polyclonal antibody and R2: topiramate-ooated microparticles. A six-level set of Seradyn QMS® Topiramate Cali three-level set of Seradyn QMS® Topiramate Controls is used for quality control of the assay.

Here's an analysis of the Seradyn QMS® Topiramate assay based on the provided 510(k) summary, structured to address your specific points:

Seradyn QMS® Topiramate Assay Study Analysis

1. Table of Acceptance Criteria and Reported Device Performance:

2. Sample Size for the Test Set and Data Provenance:

• Accuracy: 12 concentrations for recovery study, each analyzed in triplicate (total of 36 measurements).
• Linearity: 9 concentrations, number of replicates not specified.
• Sensitivity (LOQ): Not specified directly, but implies multiple measurements around the LOQ value to determine CV and recovery.
• Precision: 3 controls, N=80 for each (total 240 measurements for precision components).
• Method Comparison: N = 148 patient samples.
• Interference (Endogenous & HAMA): Not explicitly stated, but for each interferent, samples with two known topiramate levels (approx. 5 and 20 µg/mL) were assayed.
• Interference (Co-Administered Drugs): Not explicitly stated, but for each compound, normal human serum with two known topiramate levels (approx. 5 and 20 µg/mL) was assayed.
• Interference (Anticoagulants): Not explicitly stated, but implied comparison of serum and plasma.

Data Provenance: The document does not specify the country of origin of the data. The studies are described as clinical testing, but it's common for these types of in vitro diagnostic studies to use banked or commercially sourced human serum/plasma samples, often without explicit geographical tags in 510(k) summaries. All studies appear to be prospective in the sense that they were designed experiments to evaluate the new device's performance against predefined criteria or a predicate device.

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

This device is an in vitro diagnostic (IVD) assay for quantitative determination of a drug concentration. The "ground truth" here is the actual concentration of topiramate in the samples. This is typically established through:

• Reference materials: For linearity and accuracy by recovery, known concentrations are prepared by precise dilution of a high calibrator.
• Reference method/predicate device: For method comparison, the predicate Innofluor® Topiramate assay serves as the reference for comparison of patient sample results.

Therefore, no human experts were used to establish the "ground truth" in the way they would be for image analysis or disease diagnosis. The "ground truth" is defined by laboratory standards, precise dilutions, and the established performance of a reference or predicate method.

4. Adjudication Method for the Test Set:

Not applicable, as the ground truth is quantitative (actual concentration) and not based on human interpretation requiring adjudication.

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

No, an MRMC comparative effectiveness study was not done. This type of study is relevant for diagnostic imaging where multiple human readers interpret cases, and AI assistance might impact their performance. For a quantitative IVD assay, the performance is measured directly by analytical metrics (accuracy, precision, linearity, etc.) and comparison to a predicate device or reference method, not by human reader performance.

6. Standalone Performance:

Yes, the studies described (Accuracy, Linearity, Sensitivity, Precision, Specificity, Interferences, Stability) evaluate the algorithm's entire workflow (reagent interaction, measurement, and result calculation) standalone, without human-in-the-loop performance influencing the primary measurements. The assay quantifies topiramate concentration directly.

7. Type of Ground Truth Used:

• Known concentrations: For Accuracy by Recovery, Linearity, Sensitivity studies. These are prepared laboratory standards.
• Predicate device results: For Method Comparison, the results from the Seradyn Innofluor® Topiramate assay (K970510) on patient samples serve as the comparison point.
• Laboratory-spiked samples: For interference studies, known amounts of interferent and topiramate are added to serum samples.

8. Sample Size for the Training Set:

The document does not provide a sample size for a "training set." This assay is a homogeneous particle-enhanced turbidimetric immunoassay (PETIA), which is a chemical reaction-based method, not a machine learning or AI algorithm that typically requires a large "training set" of data in the common sense. The "development" or "optimization" of the assay would involve various experiments, but these are not usually referred to as a "training set" in the context of conventional IVD development. The calibration of the device uses a six-level set of Seradyn QMS® Topiramate Calibrators, but this is for operational calibration, not model training.

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

As noted above, the concept of a "training set" with established ground truth as in AI/ML is not directly applicable to this type of chemical immunoassay. The "ground truth" for calibrators and controls used in assay development and validation would be established through highly accurate reference methods, gravimetric/volumetric preparation, and traceability to established standards for the analyte (topiramate).

Ask a specific question about this device