(23 days)
The Elecsys Anti-TPO immunoassay is for the in vitro quantitative determination of antibodies to thyroid peroxidase in human serum and plasma. The anti-TPO determination is used as an aid in the diagnosis of autoimmune thyroid diseases.
The electrochemiluminescence immunoassay "ECLIA" is intended for use on the Roche Elecsys 1010/2010 and MODULAR ANALYTICS E170 (Elecsys module) immunoassay analyzers.
The COBAS Elecsys® Anti-TPO Test System is based on a competitive immunoassay with streptavidin microparticles and electrochemiluminescence detection. First and second incubations are nine minutes in duration. The reaction mixture is aspirated into the measuring cell where the microparticles are magnetically captured onto the surface of the electrode, unbound substances are removed. Voltage is applied to the electrode inducing chemiluminescent emission which is measured by a photomultiplier. Results are determined using a calibration curve that is generated specifically on each instrument by a 2 point calibration and a master curve provided with the reagent bar code.
This K051890 submission for the COBAS Elecsys® anti-TPO device is a modification of an existing device (K000155). The acceptance criteria and supporting evidence are presented for the modified device by showing its equivalence to the predicate device.
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are implicitly met by demonstrating that the modified device performs "Same" as the predicate device (K000155) across several key technical specifications and performance characteristics. The primary change highlighted is related to Biotin Interference, where the predicate allowed up to 60 ng/ml and the modified device has an acceptance criteria of up to 10 ng/ml. This suggests an improvement or a more stringent and defined limit for the modified device.
| Acceptance Criteria Category | Predicate Device (K000155) Performance | COBAS Elecsys® Anti-TPO (Modified Device) Performance | Met Acceptance Criteria? |
|---|---|---|---|
| Intended Use | for the quantitative determination of antibodies to thyroid peroxidase in human serum and plasma. | Same | Yes |
| Indication for Use | as an aid in the diagnosis of autoimmune thyroid diseases | Same | Yes |
| Sample Type | human serum and plasma | Same | Yes |
| Dilution Performance | Autoantibodies are heterogeneous and this may lead to non-linear dilution phenomena for certain individual samples. | Same | Yes |
| Traceability / Standardization | WHO 66/387 | Same | Yes |
| Test Principle | Competitive chemiluminescence | Same | Yes |
| Measuring Range | 5 - 600 IU/ml | Same | Yes |
| Reagent Stability (Unopened) | at 2-8°C up to the expiration date. | Same | Yes |
| Reagent Stability (Opened, 2-8°C) | up to six weeks. | Same | Yes |
| Reagent Stability (Opened, on E170 / 2010) | two weeks | Same | Yes |
| Reagent Stability (Opened, on 1010) | one week (store alternately in refrigerator and on analyzer - at ambient temperature 20-25 °C; up to 20 hours in total). | Same | Yes |
| Interference - Bilirubin | up to 66 mg/dl | Same | Yes |
| Interference - Hemolysis | up to 1.5 g/dl | Same | Yes |
| Interference - Lipemia | up to 2100 mg/dl | Same | Yes |
| Interference - Biotin | up to 60 ng/ml | up to 10 ng/ml | Yes (More stringent/defined) |
| Interference - Rheumatoid factors | up to 1500 U/ml | Same | Yes |
2. Sample size used for the test set and the data provenance
The document does not explicitly state the sample size used for the test set or the data provenance (e.g., country of origin, retrospective/prospective). The submission relies on demonstrating equivalence to a predicate device, assuming the predicate's performance claims, which would have been supported by its own testing data during its original clearance. The listed "Limitations" for interference are typically derived from dedicated interference studies.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
This information is not provided in the document. For in vitro diagnostic devices like this immunoassay, "ground truth" often refers to the clinical diagnosis or a well-established reference method. The document implicitly uses the predicate device as the comparison for "ground truth" in terms of performance characteristics.
4. Adjudication method for the test set
This information is not provided. Given the nature of an immunoassay, the "adjudication method" would likely involve comparing results to a reference method or clinical diagnoses, rather than human expert agreement on interpretation.
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
This is an immunoassay device, not an AI-assisted diagnostic imaging or interpretation device. Therefore, an MRMC comparative effectiveness study involving human readers and AI assistance is not applicable and was not performed.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
The device itself is a standalone immunoassay system (algorithm/device only). Its performance is evaluated intrinsically through various analytical studies (e.g., precision, measuring range, interference) to ensure it meets performance specifications, and in this case, demonstrates equivalence to a predicate device. The document implies these standalone performances were assessed to confirm the "Same" claims.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
For the purpose of this 510(k) submission, the "ground truth" is largely implied to be the established performance characteristics and validation of the predicate device (Elecsys Anti-TPO, K000155). The submission is based on demonstrating substantial equivalence to this legally marketed device across all critical performance parameters. For inherent analytical validation, the "ground truth" for parameters like accuracy and precision would typically rely on reference methods, spiked samples, and internal controls. For clinical utility, the "aid in the diagnosis of autoimmune thyroid diseases" would be linked to clinical diagnoses validated by other means (e.g., patient history, other diagnostic tests).
8. The sample size for the training set
This information is not provided. Immunoassay development typically involves extensive characterization and optimization, but the concept of a "training set" in the machine learning sense is not directly applicable to a traditional immunoassay. The development and optimization data would serve a similar purpose.
9. How the ground truth for the training set was established
As with the previous point, the concept of a "training set" with a defined "ground truth" in the AI/ML context doesn't directly apply here. Instead, during the development of an immunoassay, the "ground truth" for various analytical studies (e.g., sensitivity, specificity, linearity, interference) would be established using:
- Reference materials/standards: For quantitative measurements and calibration.
- Known positive and negative samples: For initial analytical performance characterization.
- Clinical samples with established diagnoses: To assess clinical performance and aid in setting cut-off values.
The submission focuses on demonstrating that the modified device performs identically to the predicate device across critical parameters, with a specified change in biotin interference tolerance.
§ 866.5870 Thyroid autoantibody immunological test system.
(a)
Identification. A thyroid autoantibody immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the thyroid autoantibodies (antibodies produced against the body's own tissues). Measurement of thyroid autoantibodies may aid in the diagnosis of certain thyroid disorders, such as Hashimoto's disease (chronic lymphocytic thyroiditis), nontoxic goiter (enlargement of thyroid gland), Grave's disease (enlargement of the thyroid gland with protrusion of the eyeballs), and cancer of the thyroid.(b)
Classification. Class II (performance standards).