(67 days)
The BioFire® COVID-19 Test 2 is a qualitative nested multiplexed RT-PCR in vitro diagnostic test intended for use with the BioFire® FilmArray® 2.0 and BioFire® FilmArray® Torch Systems. The BioFire COVID-19 Test 2 detects nucleic acids from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in nasopharyngeal swabs (NPS) from symptomatic individuals suspected of COVID-19 by their healthcare provider.
Results are for the identification of SARS-CoV-2 RNA. The SARS-CoV-2 RNA is generally detectable in NPS specimens during the acute phase of infection. Positive results are indicative of the presence of SARS-CoV-2 RNA; clinical correlation with patient history and other diagnostic information is necessary to determine patient infection status. Positive results do not rule out co-infection with other pathogens.
Results are meant to be used in conjunction with other clinical, epidemiologic, and laboratory data, in accordance with the guidelines provided by the relevant public health authorities. The BioFire COVID-19 Test 2 is intended for use by trained medical and laboratory professionals in a laboratory setting or under the supervision of a trained laboratory professional.
For In Vitro Diagnostic Use.
The BioFire COVID-19 Test 2 is a multiplexed nucleic acid-based test for the detection of SARS-CoV-2 RNA from nasopharyngeal swabs (NPS) eluted in either transport medium or saline. The test was originally described and cleared in K211079. The BioFire COVID-19 Test 2 uses BioFire FilmArray technology and is for use with BioFire FilmArray 2.0 and BioFire FilmArray Torch instruments. Once the sample is injected into the FilmArray pouch is loaded into the Film Array instrument which performs all aspects of testing including nucleic acid extraction, reverse-transcription, and nested PCR with melt analysis. The currently cleared version of the test uses three SARS-CoV-2 assays and returns a 'SARS-CoV-2 Detected' call if one or more of the SARS-CoV-2 assays are positive.
The purpose of this submission is to display results for four additional SARS-CoV-2 assays which are currently present on the test, but for which results are masked through software. The assays are being unmasked as a mitigation against the risk of future SARS-CoV-2 variants affecting the sensitivity of the BioFire COVID-19 Test 2 due to mutations in assay primer regions. Note that to date BioFire Defense has not identified any variants that are predicted to affect the performance of the three-assay version of BioFire COVID-19 Test 2 described in K211079. These changes are being requested preemptively. The calling scheme when using the seven total SARS-CoV-2 assays will remain unchanged: one or more positive SARS-CoV-2 assay results will return an overall 'SARS-CoV-2 Detected' result.
Here's a breakdown of the acceptance criteria and the study details for the BioFire COVID-19 Test 2 based on the provided document:
1. Table of Acceptance Criteria and Reported Device Performance
The provided document describes a Special 510(k) submission where the primary change is the unmasking of four additional SARS-CoV-2 assays within an already cleared device (BioFire COVID-19 Test 2, K211079). Therefore, the "acceptance criteria" are implied by demonstrating equivalence to the predicate device's performance. The re-analysis of prior studies with the modified software is used to show this equivalence.
Since this is a submission for a software modification to unmask existing assays and not a de novo submission establishing new performance benchmarks, the acceptance criteria are largely defined by matching or showing no significant degradation from the predicate device's performance.
| Acceptance Criteria (Implied by Predicate Equivalence) | Reported Device Performance (Modified BioFire COVID-19 Test 2) |
|---|---|
| Bench Testing | |
| No unexpected reactivity (Specificity) | No unexpected reactivity observed with any organisms/viruses. Performance equivalent to predicate device (DF-SDY-029903, DF-SDY-030333). |
| Equivalent Sensitivity (LoD - infectious virus) | 3.3E+02 GC/mL (effectively equivalent to predicate device) (DF-SDY-029904). |
| Equivalent Sensitivity (LoD - inactivated virus) | 3.3E+02 GE/mL (equivalent to predicate device) (DF-SDY-030331). |
| No inhibition by common substances | None of the substances tested were inhibitory. Performance equivalent to predicate device (DF-SDY-030334). |
| 100% detection rate for various storage conditions | Detection rate for all evaluated samples and storage conditions was 100%. Performance equivalent to predicate device (DF-SDY-030336). |
| Comparable results for FDA-provided analytes | Overall results for testing the FDA Reference Panel are comparable to the predicate device (DF-SDY-030358). |
| >95% Percent Agreement (Reproducibility) | >95% agreement for each sample and site, except negative samples at Site 2 (93.3% for both subject and predicate device). Performance equivalent to predicate device (DF-SDY-030398). |
| Near LoD detection of strains (Reactivity/Inclusivity) | All four strains tested were detected at near LoD concentrations. Performance equivalent to predicate device (DF-SDY-030404). |
| 100% detection rate for NPS in saline (1x LoD) | 20/20 (100%) detection rate. Performance equivalent to predicate device (DF-SDY-030666). |
| 20 months stability at 18-30°C | Demonstrated 20 months of stability at 18-30°C (DF-SDY-030316). |
| Clinical Testing | |
| PPA and NPA equivalent to predicate device | PPA (Positive Percent Agreement): 98.6% (68/69). NPA (Negative Percent Agreement): 99.1% (450/454). Overall performance equivalent to predicate device (PPA 98.6%, NPA 99.6%) (DF-SDY-030617). The minor difference in NPA (99.1% vs 99.6%) is stated to be "equivalent." |
| In Silico Analyses | |
| No significant amplification of non-target sequences | Only near-neighbor non-human coronavirus genomes showed significant homology to assay-specific PCR2 primers, unlikely to be found in human respiratory samples (DF-SDY-030174). |
| Broad SARS-CoV-2 strain detection | No sequences submitted to GISAID before May 4, 2022, identified with co-occurring mutations impacting all assays. Predicted detection of all SARS-CoV-2 strains including VOCs, VOIs, and VUMs (DF-OTH-030895). |
2. Sample Size Used for the Test Set and Data Provenance
The document states that no additional testing was performed for this submission. Instead, all study data previously submitted in K211079 were re-analyzed using the updated software.
Therefore, the "test set" for this specific submission is the re-analysis of data from the original K211079 (and potentially EUA200044) studies.
- Clinical Testing (DF-SDY-030617):
- Sample Size: 69 positive samples, 454 negative samples. (Total = 523 samples)
- Data Provenance: Prospective Clinical Evaluation. The document does not explicitly state the country of origin, but generally, FDA submissions for predicate devices are expected to include data from diverse geographic regions within the US, or from regions with comparable patient populations.
- Bench Testing: Sample sizes vary per study. For example:
- LoD studies (DF-SDY-029904, DF-SDY-030331) involve serial dilutions and replicates.
- Specificity/Exclusivity (DF-SDY-029903, DF-SDY-030333) involve testing a panel of organisms/viruses.
- Reproducibility (DF-SDY-030398) involves testing replicates across multiple sites.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The ground truth for the clinical samples (DF-SDY-030617) would typically be established by a reference method, most commonly another FDA-authorized RT-PCR assay. The document does not specify the number or qualifications of experts involved in determining the ground truth for the clinical samples. For molecular diagnostics, "expert consensus" is less common for ground truth than established reference tests.
For bench testing studies (e.g., LoD, inclusivity, exclusivity), the ground truth is based on the known concentration of spiked analytes or the known identity of the assayed organisms/viruses, which does not typically involve human experts establishing ground truth in the same way as clinical image interpretation.
4. Adjudication Method for the Test Set
The document does not describe an adjudication method for the test set regarding human interpretation, as the device is an in vitro diagnostic (IVD) molecular test for direct detection of SARS-CoV-2 RNA. Results are determined by the instrument and its software.
For the clinical study, the reference method used to establish positive/negative status for the clinical samples would be the "adjudication." However, the method (e.g., comparison to a composite reference standard, or another cleared test) is not detailed here.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done
No, an MRMC comparative effectiveness study was not done. This device is an in vitro diagnostic (IVD) device that performs a laboratory test. It does not involve human readers interpreting images or data with or without AI assistance. The output is a "SARS-CoV-2 Detected" or "SARS-CoV-2 Not Detected" result.
6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) was done
Yes, the performance presented is standalone/algorithm only. The BioFire COVID-19 Test 2 is an IVD automated system. The results are generated directly by the device's software based on its internal processes (nucleic acid extraction, RT-PCR, melt analysis) without human interpretation of raw data. The study validates the device's ability to detect SARS-CoV-2 RNA independently. The phrasing "Software uses results from 7 assays" further confirms this.
7. The Type of Ground Truth Used
- Clinical Testing (DF-SDY-030617): The ground truth for the prospective clinical evaluation samples would most commonly be established by a highly sensitive and specific reference molecular assay (e.g., another FDA-cleared or EUA RT-PCR test for SARS-CoV-2), possibly combined with clinical diagnosis, but the document does not explicitly state this.
- Bench Testing:
- LoD, Reactivity (Inclusivity): Ground truth is based on the known concentration and identity of specific SARS-CoV-2 strains/genomic material spiked into negative matrix.
- Specificity (Exclusivity): Ground truth is based on the known identity of other respiratory pathogens or commensals tested.
- Interfering Substances: Ground truth is based on the known presence of potential interfering substances without SARS-CoV-2.
- In Silico Analysis: Ground truth is based on publicly available genetic sequence databases (e.g., GISAID for SARS-CoV-2 variants).
8. The Sample Size for the Training Set
The document does not mention a separate training set for this submission. The purpose of this submission is to unmask existing assays on an already established device. The performance data presented are from validation and verification studies (effectively "test sets") previously conducted for the predicate device. For the original development of the BioFire COVID-19 Test 2 assays, various internal optimization and calibration steps (which could be considered analogous to "training") would have occurred, but these details are not part of this 510(k) summary.
9. How the Ground Truth for the Training Set was Established
As no specific "training set" is described for this 510(k) modification, this question is not directly applicable. For the initial development of the assays, the ground truth would have been established through a combination of:
- Bioinformatics: Designing primers and probes based on known SARS-CoV-2 sequences.
- Analytical studies: Testing synthetic targets and cultured virus at known concentrations.
- Clinical studies: Initial evaluation with patient samples where SARS-CoV-2 status was determined by a reference method.
§ 866.3981 Device to detect and identify nucleic acid targets in respiratory specimens from microbial agents that cause the SARS-CoV-2 respiratory infection and other microbial agents when in a multi-target test.
(a)
Identification. A device to detect and identify nucleic acid targets in respiratory specimens from microbial agents that cause the SARS-CoV-2 respiratory infection and other microbial agents when in a multi-target test is an in vitro diagnostic device intended for the detection and identification of SARS-CoV-2 and other microbial agents when in a multi-target test in human clinical respiratory specimens from patients suspected of respiratory infection who are at risk for exposure or who may have been exposed to these agents. The device is intended to aid in the diagnosis of respiratory infection in conjunction with other clinical, epidemiologic, and laboratory data or other risk factors.(b)
Classification. Class II (special controls). The special controls for this device are:(1) The intended use in the labeling required under § 809.10 of this chapter must include a description of the following: Analytes and targets the device detects and identifies, the specimen types tested, the results provided to the user, the clinical indications for which the test is to be used, the specific intended population(s), the intended use locations including testing location(s) where the device is to be used (if applicable), and other conditions of use as appropriate.
(2) Any sample collection device used must be FDA-cleared, -approved, or -classified as 510(k) exempt (standalone or as part of a test system) for the collection of specimen types claimed by this device; alternatively, the sample collection device must be cleared in a premarket submission as a part of this device.
(3) The labeling required under § 809.10(b) of this chapter must include:
(i) A detailed device description, including reagents, instruments, ancillary materials, all control elements, and a detailed explanation of the methodology, including all pre-analytical methods for processing of specimens;
(ii) Detailed descriptions of the performance characteristics of the device for each specimen type claimed in the intended use based on analytical studies including the following, as applicable: Limit of Detection, inclusivity, cross-reactivity, interfering substances, competitive inhibition, carryover/cross contamination, specimen stability, precision, reproducibility, and clinical studies;
(iii) Detailed descriptions of the test procedure(s), the interpretation of test results for clinical specimens, and acceptance criteria for any quality control testing;
(iv) A warning statement that viral culture should not be attempted in cases of positive results for SARS-CoV-2 and/or any similar microbial agents unless a facility with an appropriate level of laboratory biosafety (
e.g., BSL 3 and BSL 3+, etc.) is available to receive and culture specimens; and(v) A prominent statement that device performance has not been established for specimens collected from individuals not identified in the intended use population (
e.g., when applicable, that device performance has not been established in individuals without signs or symptoms of respiratory infection).(vi) Limiting statements that indicate that:
(A) A negative test result does not preclude the possibility of infection;
(B) The test results should be interpreted in conjunction with other clinical and laboratory data available to the clinician;
(C) There is a risk of incorrect results due to the presence of nucleic acid sequence variants in the targeted pathogens;
(D) That positive and negative predictive values are highly dependent on prevalence;
(E) Accurate results are dependent on adequate specimen collection, transport, storage, and processing. Failure to observe proper procedures in any one of these steps can lead to incorrect results; and
(F) When applicable (
e.g., recommended by the Centers for Disease Control and Prevention, by current well-accepted clinical guidelines, or by published peer-reviewed literature), that the clinical performance may be affected by testing a specific clinical subpopulation or for a specific claimed specimen type.(4) Design verification and validation must include:
(i) Detailed documentation, including performance results, from a clinical study that includes prospective (sequential) samples for each claimed specimen type and, as appropriate, additional characterized clinical samples. The clinical study must be performed on a study population consistent with the intended use population and compare the device performance to results obtained using a comparator that FDA has determined is appropriate. Detailed documentation must include the clinical study protocol (including a predefined statistical analysis plan), study report, testing results, and results of all statistical analyses.
(ii) Risk analysis and documentation demonstrating how risk control measures are implemented to address device system hazards, such as Failure Modes Effects Analysis and/or Hazard Analysis. This documentation must include a detailed description of a protocol (including all procedures and methods) for the continuous monitoring, identification, and handling of genetic mutations and/or novel respiratory pathogen isolates or strains (
e.g., regular review of published literature and periodic in silico analysis of target sequences to detect possible mismatches). All results of this protocol, including any findings, must be documented and must include any additional data analysis that is requested by FDA in response to any performance concerns identified under this section or identified by FDA during routine evaluation. Additionally, if requested by FDA, these evaluations must be submitted to FDA for FDA review within 48 hours of the request. Results that are reasonably interpreted to support the conclusion that novel respiratory pathogen strains or isolates impact the stated expected performance of the device must be sent to FDA immediately.(iii) A detailed description of the identity, phylogenetic relationship, and other recognized characterization of the respiratory pathogen(s) that the device is designed to detect. In addition, detailed documentation describing how to interpret the device results and other measures that might be needed for a laboratory diagnosis of respiratory infection.
(iv) A detailed device description, including device components, ancillary reagents required but not provided, and a detailed explanation of the methodology, including molecular target(s) for each analyte, design of target detection reagents, rationale for target selection, limiting factors of the device (
e.g., saturation level of hybridization and maximum amplification and detection cycle number, etc.), internal and external controls, and computational path from collected raw data to reported result (e.g., how collected raw signals are converted into a reported signal and result), as applicable.(v) A detailed description of device software, including software applications and hardware-based devices that incorporate software. The detailed description must include documentation of verification, validation, and hazard analysis and risk assessment activities, including an assessment of the impact of threats and vulnerabilities on device functionality and end users/patients as part of cybersecurity review.
(vi) For devices intended for the detection and identification of microbial agents for which an FDA recommended reference panel is available, design verification and validation must include the performance results of an analytical study testing the FDA recommended reference panel of characterized samples. Detailed documentation must be kept of that study and its results, including the study protocol, study report for the proposed intended use, testing results, and results of all statistical analyses.
(vii) For devices with an intended use that includes detection of Influenza A and Influenza B viruses and/or detection and differentiation between the Influenza A virus subtypes in human clinical specimens, the design verification and validation must include a detailed description of the identity, phylogenetic relationship, or other recognized characterization of the Influenza A and B viruses that the device is designed to detect, a description of how the device results might be used in a diagnostic algorithm and other measures that might be needed for a laboratory identification of Influenza A or B virus and of specific Influenza A virus subtypes, and a description of the clinical and epidemiological parameters that are relevant to a patient case diagnosis of Influenza A or B and of specific Influenza A virus subtypes. An evaluation of the device compared to a currently appropriate and FDA accepted comparator method. Detailed documentation must be kept of that study and its results, including the study protocol, study report for the proposed intended use, testing results, and results of all statistical analyses.
(5) When applicable, performance results of the analytical study testing the FDA recommended reference panel described in paragraph (b)(4)(vi) of this section must be included in the device's labeling under § 809.10(b) of this chapter.
(6) For devices with an intended use that includes detection of Influenza A and Influenza B viruses and/or detection and differentiation between the Influenza A virus subtypes in human clinical specimens in addition to detection of SARS-CoV-2 and similar microbial agents, the required labeling under § 809.10(b) of this chapter must include the following:
(i) Where applicable, a limiting statement that performance characteristics for Influenza A were established when Influenza A/H3 and A/H1-2009 (or other pertinent Influenza A subtypes) were the predominant Influenza A viruses in circulation.
(ii) Where applicable, a warning statement that reads 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 departments for testing. Viral culture should not be attempted in these cases unless a BSL 3+ facility is available to receive and culture specimens.
(iii) Where the device results interpretation involves combining the outputs of several targets to get the final results, such as a device that both detects Influenza A and differentiates all known Influenza A subtypes that are currently circulating, the device's labeling must include a clear interpretation instruction for all valid and invalid output combinations, and recommendations for any required followup actions or retesting in the case of an unusual or unexpected device result.
(iv) A limiting statement that if a specimen yields a positive result for Influenza A, but produces negative test results for all specific influenza A subtypes intended to be differentiated (
i.e., H1-2009 and H3), this result requires notification of appropriate local, State, or Federal public health authorities to determine necessary measures for verification and to further determine whether the specimen represents a novel strain of Influenza A.(7) If one of the actions listed at section 564(b)(1)(A) through (D) of the Federal Food, Drug, and Cosmetic Act occurs with respect to an influenza viral strain, or if the Secretary of Health and Human Services determines, under section 319(a) of the Public Health Service Act, that a disease or disorder presents a public health emergency, or that a public health emergency otherwise exists, with respect to an influenza viral strain:
(i) Within 30 days from the date that FDA notifies manufacturers that characterized viral samples are available for test evaluation, the manufacturer must have testing performed on the device with those influenza viral samples in accordance with a standardized protocol considered and determined by FDA to be acceptable and appropriate.
(ii) Within 60 days from the date that FDA notifies manufacturers that characterized influenza viral samples are available for test evaluation and continuing until 3 years from that date, the results of the influenza emergency analytical reactivity testing, including the detailed information for the virus tested as described in the certificate of authentication, must be included as part of the device's labeling in a tabular format, either by:
(A) Placing the results directly in the device's labeling required under § 809.10(b) of this chapter that accompanies the device in a separate section of the labeling where analytical reactivity testing data can be found, but separate from the annual analytical reactivity testing results; or
(B) In a section of the device's label or in other labeling that accompanies the device, prominently providing a hyperlink to the manufacturer's public website where the analytical reactivity testing data can be found. The manufacturer's website, as well as the primary part of the manufacturer's website that discusses the device, must provide a prominently placed hyperlink to the website containing this information and must allow unrestricted viewing access.