(42 days)
The ID NOW Influenza A & B 2 assay performed on the ID NOW Instrument is a rapid molecular in vitro diagnostic test utilizing an isothermal nucleic acid amplification technology for the qualitative detection and discrimination of influenza A and B viral RNA in direct nasal or nasopharyngeal swabs and nasal or nasopharyngeal swabs eluted in viral transport media from patients with signs and symptoms of respiratory infection. It is intended for use as an aid in the differential diagnosis of influenza A and B viral infections in conjunction with clinical and epidemiological risk factors. The assay is not intended to detect the presence of influenza C virus.
Negative results do not preclude influenza virus infection and should not be used as the sole basis for diagnosis, treatment or other patient management decisions.
If infection with a novel influenza A virus is suspected based on current clinical and epidemiological screening criteria recommended by public health authorities, specimens should be collected with appropriate infection control precautions for novel virulent Influenza viruses and sent to state or local health department for testing. Viral culture should not be attempted in these cases unless a BSL 3+ facility is available to receive and culture specimens.
ID NOW Influenza A & B 2 is a rapid, instrument-based isothermal test for the qualitative detection and differentiation of influenza A and influenza B from nasal or nasopharyngeal swabs tested directly or after elution in viral transport media collected from patients presenting with signs and symptoms of respiratory infection.
The ID NOW Influenza A & B 2 system utilizes isothermal nucleic acid amplification technology and is comprised of:
- Sample Receiver single use, disposable containing the elution buffer
- Test Base - single use, disposable comprising two sealed reaction tubes, each containing a lyophilized pellet
- Transfer Cartridge single use, disposable for transfer of the eluted sample to the Test Base, and
- ID NOW Instrument repeat use reader.
The reaction tubes in the Test Base contain the reagents required for amplification of the target nucleic acid and an internal control. ID NOW Influenza A & B 2 utilizes a pair of templates (similar to primers) for the specific amplification of RNA from influenza A and B and a fluorescently labeled molecular beacon designed to specifically identify the amplified RNA targets.
ID NOW Influenza A & B 2 is performed within the confinement of the Test Base, and no other part of the ID NOW Instrument has contact with the sample during the amplification process. This reduces the risk of instrument contamination and sample carry-over between measurements.
To perform the assay, the Sample Receiver and Test Base are inserted into the ID NOW Instrument and the elution buffer is automatically heated by the instrument. The sample is added to the Sample Receiver and transferred via the Transfer Cartridge to the Test Base, resuspending the lyophilized pellets contained within the Test Base and initiating target amplification. Heating, mixing and detection by fluorescence is provided by the instrument, with results automatically reported.
Results are displayed by the ID NOW Instrument and are also stored in an on-board archive and are assigned to a sample ID that has been entered into the ID NOW Instrument by the operator, and the date/time the test was performed. Data can be retrieved and downloaded by the operator at any time after testing. An external Alere™ Universal Printer can be attached via USB to the ID NOW Instrument to print test results.
The provided FDA 510(k) clearance letter and summary for the "ID NOW Influenza A & B 2" device (K190204) primarily focus on a labeling modification to expand specimen transport and storage instructions. It explicitly states: "This is a labeling update only, there have been no changes to the Intended Use or fundamental scientific technology of the ID NOW Influenza A & B 2 assay."
Therefore, this document does not contain the details of an acceptance criteria study or the detailed performance data as would be found in an original 510(k) submission for the device itself. Instead, it refers to the predicate device (K173932), implying that the performance criteria and supporting studies were established and documented during the clearance of that predicate device.
Based on the provided text, I cannot describe a new acceptance criteria study or new performance data for K190204, as this submission explicitly states none were performed for the device's fundamental function.
However, I can extract information related to the device itself and its general intended use, and explain why the requested information isn't present in this specific document.
Analysis of Provided Document's Relevance to Acceptance Criteria and Study Details:
The current document (K190204) is a "Special 510(k)" submission for a modification to an already cleared device. This type of submission does not typically include a full re-evaluation of the device's fundamental performance unless the modification directly impacts its safety or effectiveness in a new way. In this case, the modification is explicitly stated as only a labeling change related to specimen storage.
Therefore, the document does not provide the following information directly:
- A table of acceptance criteria and reported device performance for K190204 itself, because no new performance study was conducted for this specific submission. The performance data would have been part of the original submission for K173932.
- Sample sizes used for a test set for this submission.
- Protocols for establishing ground truth (experts, adjudication, etc.) for a substantial performance study.
- Details of MRMC studies or effect sizes.
- Standalone performance data (as this is a labeling update, not a new device or performance claim).
- Details on training set sample size or ground truth establishment for a new AI/algorithm (as this is a molecular diagnostic test, not an AI-based imaging diagnostic).
Information that can be inferred or directly stated from the document:
- Device Type: Rapid molecular in vitro diagnostic test. This is important because the requested ground truth types (pathology, expert consensus) are more relevant to imaging AI; for molecular diagnostics, ground truth is typically established by definitive laboratory methods (e.g., PCR reference methods, viral culture).
- Technology: Isothermal nucleic acid amplification technology.
- Targets: Influenza A and B viral RNA.
- Sample Type: Direct nasal or nasopharyngeal swabs, and nasal/nasopharyngeal swabs eluted in viral transport media.
- Result Type: Qualitative (detection/discrimination).
- Internal Control: Yes.
- Result Interpretation: Automated.
- Predicate Device: K173932 (ID NOW Influenza A & B 2). This implies that the validation and acceptance criteria for performance were established during the clearance of K173932.
Hypothetical Example of how the requested information would be presented for a diagnostic device, if this document were an original submission with performance data:
If this were an original 510(k) submission for a new diagnostic device requiring clinical validation, the document would typically include sections detailing:
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Acceptance Criteria and Performance:
Performance Metric Acceptance Criteria (e.g., % Concordance) Reported Performance (e.g., % Concordance, Sensitivity, Specificity) Overall Agreement ≥ 95% 97.2% Positive Agreement (PPA) for Flu A ≥ 90% (vs. Comparator X) 93.5% (vs. RT-qPCR) Negative Agreement (NPA) for Flu A ≥ 95% (vs. Comparator X) 98.1% (vs. RT-qPCR) Positive Agreement (PPA) for Flu B ≥ 90% (vs. Comparator X) 92.8% (vs. RT-qPCR) Negative Agreement (NPA) for Flu B ≥ 95% (vs. Comparator X) 97.5% (vs. RT-qPCR) Limit of Detection Defined concentration (e.g., X copies/mL) Y copies/mL Cross-Reactivity No cross-reactivity with specified organisms No cross-reactivity with A, B, C... Note: The specific metrics and thresholds would depend on the device type and intended use. -
Sample Sizes and Data Provenance (for test set, if applicable to a clinical study):
- Sample Size: e.g., 500 clinical samples (250 positive, 250 negative)
- Data Provenance: Prospective collection from multiple clinical sites in the USA. Samples collected from patients presenting with signs/symptoms of respiratory infection during influenza season.
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Ground Truth Establishment (for test set, if applicable):
- Number of Experts/Reference Methods: Ground truth established by a highly sensitive and specific reference method, such as real-time Reverse Transcription Polymerase Chain Reaction (RT-qPCR) with validated primers and probes, performed by a CLIA-certified laboratory.
- Qualifications of Experts (if human review was part of GT): Not directly applicable for a molecular test's primary ground truth, but if comparator methods involved experts, their qualifications (e.g., board-certified clinical microbiologists) would be relevant.
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Adjudication Method:
- Not applicable as primary ground truth is objective molecular test; if discordant results between the device and the reference method were analyzed, they might be adjudicated by re-testing or sequencing.
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Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
- Not applicable for a molecular diagnostic device of this type, as it does not involve human readers interpreting images or data for diagnosis. This type of study is common for AI-powered imaging devices.
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Standalone Performance:
- The "reported performance" table above is the standalone performance for a fully automated molecular diagnostic device like this. There is no "human-in-the-loop" for result interpretation.
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Type of Ground Truth Used:
- Reference molecular testing: Typically RT-qPCR or similar highly sensitive and specific molecular assays, often using independent, validated methods. In some cases, viral culture could also be used as a reference. Clinical outcomes data might be used in broader epidemiological studies but not typically as the direct ground truth for analytical device performance.
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Training Set Sample Size:
- For a molecular diagnostic test, "training set" doesn't apply in the same way as for AI. Instead, there would be extensive analytical validation data (e.g., inclusivity, exclusivity, LOD, linearity, precision) generated by testing panels of characterized specimens and analytical dilutions. The "sample size" here would refer to the number of characterized panels and replicates used for these studies.
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How the ground truth for the training set was established:
- Again, for a molecular diagnostic, this refers to how the analytical samples were characterized. This is typically done through nucleic acid sequencing, quantitative PCR, or other highly accurate methods to determine the presence, type, and concentration of the target analyte in analytical samples. Clinical samples used in analytical studies would be highly characterized using established reference methods.
In summary, while the provided document gives valuable information about the device's intended use and the specific change for this 510(k), it does not contain the detailed performance study information that would have been part of the original 510(k) submission (K173932) for the ID NOW Influenza A & B 2 device.
§ 866.3980 Respiratory viral panel multiplex nucleic acid assay.
(a)
Identification. A respiratory viral panel multiplex nucleic acid assay is a qualitative in vitro diagnostic device intended to simultaneously detect and identify multiple viral nucleic acids extracted from human respiratory specimens or viral culture. The detection and identification of a specific viral nucleic acid from individuals exhibiting signs and symptoms of respiratory infection aids in the diagnosis of respiratory viral infection when used in conjunction with other clinical and laboratory findings. The device is intended for detection and identification of a combination of the following viruses:(1) Influenza A and Influenza B;
(2) Influenza A subtype H1 and Influenza A subtype H3;
(3) Respiratory Syncytial Virus subtype A and Respiratory Syncytial Virus subtype B;
(4) Parainfluenza 1, Parainfluenza 2, and Parainfluenza 3 virus;
(5) Human Metapneumovirus;
(6) Rhinovirus; and
(7) Adenovirus.
(b)
Classification. Class II (special controls). The special controls are:(1) FDA's guidance document entitled “Class II Special Controls Guidance Document: Respiratory Viral Panel Multiplex Nucleic Acid Assay;”
(2) For a device that detects and identifies Human Metapneumovirus, FDA's guidance document entitled “Class II Special Controls Guidance Document: Testing for Human Metapneumovirus (hMPV) Using Nucleic Acid Assays;” and
(3) For a device that detects and differentiates Influenza A subtype H1 and subtype H3, FDA's guidance document entitled “Class II Special Controls Guidance Document: Testing for Detection and Differentiation of Influenza A Virus Subtypes Using Multiplex Nucleic Acid Assays.” See § 866.1(e) for the availability of these guidance documents.