(180 days)
No
The description focuses on standard RT-PCR technology, automated sample processing, and real-time fluorescent signal detection. There is no mention of AI or ML in the device description, intended use, or performance studies. The analysis of results appears to be based on predefined thresholds for signal detection rather than learned patterns.
No
The device is an in vitro diagnostic test for detecting SARS-CoV-2 RNA, used as an aid in diagnosis, not for treating or preventing disease.
Yes
The "Intended Use / Indications for Use" section explicitly states that the device is "intended for use as an aid in the diagnosis of COVID-19."
No
The device is a rapid real-time RT-PCR test that is performed on a GeneXpert Xpress System, which includes hardware components like the GeneXpert IV instrument and a GeneXpert Hub. While software is involved, it is integral to the operation of the hardware and the test itself, which involves physical sample preparation, amplification, and detection.
Yes, this device is an IVD (In Vitro Diagnostic).
Here's why:
- Intended Use/Indications for Use: The document explicitly states the test is "intended for the qualitative detection of SARS-CoV-2 RNA in nasopharyngeal and anterior nasal swab specimens collected from individuals with signs and symptoms of respiratory tract infection." This describes a test performed on samples taken from the human body to provide information for diagnosis.
- Device Description: The description clearly labels the device as a "rapid, automated in vitro diagnostic test for the qualitative detection of viral RNA from SARS-CoV-2". The term "in vitro diagnostic" is used directly.
- Mechanism: The device performs sample preparation, nucleic acid amplification (RT-PCR), and real-time fluorescent signal detection on the collected specimens, which are all processes performed outside of the living body to analyze biological samples.
Therefore, based on the provided text, the Xpert Xpress CoV-2 plus test fits the definition of an In Vitro Diagnostic device.
N/A
Intended Use / Indications for Use
The Xpert Xpress CoV-2 plus test, performed on the GeneXpert Xpress System, is a rapid real-time RT-PCR test intended for the qualitative detection of SARS-CoV-2 RNA in nasopharyngeal and anterior nasal swab specimens collected from individuals with signs and symptoms of respiratory tract infection.
The Xpert Xpress CoV-2 plus test is intended for use as an aid in the diagnosis of COVID-19 if used in conjunction with other clinical, epidemiologic, and laboratory findings. Positive results are indicative of the presence of SARS-CoV-2 RNA. Positive results do not rule out bacterial infection or co-infection with other pathogens.
Negative results do not preclude SARS-CoV-2 infection. The results of this test should not be used as the sole basis for diagnosis and patient management decisions.
Product codes
QQX, OOI
Device Description
The Xpert Xpress CoV-2 plus test is a rapid, automated in vitro diagnostic test for the qualitative detection of viral RNA from SARS-CoV-2 in nasopharyngeal swab (NPS) and anterior nasal swab (NS) specimens collected from individuals with signs and symptoms of respiratory tract infection.
The Xpert Xpress CoV-2 plus test is performed on GeneXpert Xpress System, which consist of a GeneXpert IV instrument that executes sample preparation, nucleic acid amplification and real-time fluorescent signal detection for the tests, and a GeneXpert Hub with preloaded GeneXpert Xpress software for running the tests and viewing the test results. The GeneXpert Hub accessory integrates the computer, touchscreen monitor and barcode scanner. Each of the GeneXpert modules in the GeneXpert IV instrument can perform independent sample preparation and testing. The GeneXpert Xpress System requires the use of single-use disposable cartridges that hold the RT-PCR reagents and host sample purification, nucleic acid amplification, and detection of the target sequences. Because the cartridges are selfcontained, cross-contamination between samples is minimized.
The Xpert Xpress CoV-2 plus test includes reagents for the detection of viral RNA from SARS-CoV-2 in NPS and NS specimens. The primers and probes in the Xpert Xpress CoV-2 plus test are designed to amplify and detect unique sequences in the genes that encode the following SARS-CoV-2 proteins: nucleocapsid (N2), envelope (E), and RNA-dependent RNA polymerase (RdRP). A Sample Processing Control (SPC) and a Probe Check Control (PCC) are also included in the cartridge serving as internal controls. The SPC is present to control for adequate processing of the sample and to monitor for the presence of potential inhibitor(s) in the RT-PCR reaction. The SPC also ensures that the RT-PCR reaction conditions (temperature and time) are appropriate for the amplification reaction and that the RT-PCR reagents are functional. The PCC verifies reagent rehydration, PCR tube filling, and confirms that all reaction components are present in the cartridge including monitoring for probe integrity and dye stability.
The Xpert Xpress CoV-2 plus test is designed for use with NPS or NS specimen collected with nylon flocked swabs and placed into viral transport medium (VTM), Universal Transport Medium (UTM) or eNAT®. Examples of the ancillary specimen collection kits that are compatible for use with the Xpert Xpress CoV-2 plus test include:
- Nasopharyngeal Sample Collection Kit for Viruses
- o Copan UTM® 3C057N (Flexible Minitip Flocked Swab with UTM® Medium w/o Beads)
- Becton Dickinson Universal Viral Transport Kit P/N 220531 (Flexible Minitip O Flocked Swab with UVT Medium)
- Copan eNAT® Molecular Collection and Preservation Medium P/N 6U074S01 o (Flexible Minitip Flocked Swab with eNAT® Medium)
- Nasal Sample Collection Kit for Viruses
- Copan UTM® 3C064N (Regular Flocked Swab with UTM® Medium w/o O Beads)
- Copan eNAT® Molecular Collection and Preservation Medium P/N o 6U073S01 (Regular Flocked Swab with eNAT® Medium)
- Alternatively, swabs and transport media can be obtained separately:
- Nylon flocked swab (Copan P/N 502CS01, 503CS01) O
- Viral transport medium, 3 mL (Copan P/N 3C047N, BD Universal o Transport Medium, Remel M4RT, Remel M5)
These sample collection kits for viruses allow NPS and NS specimens from patients to be collected, preserved and transported to laboratory prior to analysis with the Xpert Xpress CoV-2 plus test.
Mentions image processing
Not Found
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Not Found
Anatomical Site
Nasopharyngeal and anterior nasal swab specimens
Indicated Patient Age Range
Not Found
Intended User / Care Setting
Not Found
Description of the training set, sample size, data source, and annotation protocol
Not Found
Description of the test set, sample size, data source, and annotation protocol
Not Found
Summary of Performance Studies
- Analytical Sensitivity/Limit of Detection (LoD) - Clinical NPS Matrix:
- Study Type: LoD estimation and verification.
- Sample Size: Not explicitly stated as a single number, but involves testing limiting dilutions with 20 replicates per lot for two reagent lots and two clinical NPS matrices.
- Key Results: Estimated LoD of 403 copies/mL for NATtrol™ SARS-CoV-2 in NPS-UTM/VTM and NPS-eNAT matrices, with 100% positivity at this concentration.
- Analytical Sensitivity/Limit of Detection (LoD) - Clinical NS-UTM/VTM Matrix:
- Study Type: LoD estimation and verification.
- Sample Size: Not explicitly stated as a single number, but involves testing limiting dilutions with 20 replicates per lot for two reagent lots.
- Key Results: Estimated LoD of 462 copies/mL for NATtrol™ SARS-CoV-2 in NS-UTM/VTM matrix, with 100% positivity at this concentration.
- Analytical Sensitivity (Limit of Detection) - WHO First International Standard SARS-CoV-2 RNA in clinical NS-UTM/VTM matrix:
- Study Type: LoD verification using WHO International Standard.
- Sample Size: 20 replicates.
- Key Results: Verified LoD of 1000 IU/mL for the First WHO International Standard for SARS-CoV-2 RNA in NS-UTM/VTM matrix, with 20/20 overall positive results (19/20 for N2 target).
- Analytical Reactivity (Inclusivity) - SARS-CoV-2 in silico Analyses:
- Study Type: In silico analysis of primer and probe sequences against GISAID gene database.
- Sample Size: 11,650,640 SARS-CoV-2 sequences (initial) and 2,691,091 SARS-CoV-2 sequences (updated) for amplicons; 10,310,839 sequences (initial) and 2,519,206 sequences (updated) for probes.
- Key Results: Predicted inclusivity of 99.95% to 100% for amplicons and 99.6% to 100% for probes across E, N2, and RdRP targets for variants of interest and concern. No specific primer/probe sequence was observed with >0.5% frequency of mismatch during a 180-day period.
- Analytical Reactivity (Inclusivity) - SARS-CoV-2 Wet-Testing:
- Study Type: Bench testing against multiple SARS-CoV-2 strains.
- Sample Size: 61 strains (23 intact viral particles, 38 in vitro RNA transcripts).
- Key Results: All 61 SARS-CoV-2 strains tested positive in all three replicates at levels near 3x LoD.
- Analytical Specificity (Exclusivity) - In Silico Analyses:
- Study Type: In silico analysis of primers and probes against microorganism sequences from NCBI database.
- Key Results: No potential unintended cross-reactivity expected, except for SARS-coronavirus where the E gene target is shared.
- Analytical Specificity (Exclusivity) - Wet-Testing:
- Study Type: Bench-testing a panel of 62 microorganisms.
- Sample Size: 62 microorganisms.
- Key Results: No cross-reactivity observed with non-intended respiratory microorganisms and phylogenetically related human coronavirus species, except for SARS-coronavirus, Urbani, which resulted in expected SARS-CoV-2 POSITIVE due to shared E gene target.
- Microbial Interference:
- Study Type: Assessment of inhibitory effects of commensal microorganisms.
- Sample Size: 18 commensal microorganisms, tested with 8 replicates each.
- Key Results: No interference by the listed commensal viral or bacterial strains was reported at the concentrations tested; all 8 of 8 positive replicate samples were correctly identified as SARS-CoV-2 POSITIVE.
- Potentially Interfering Substances:
- Study Type: Evaluation of substances potentially interfering with detection.
- Sample Size: 23 potentially interfering substances, with 8 negative and 8 positive samples tested per substance.
- Key Results: Interfering effects observed for fluticasone propionate and mucin type I-S at higher concentrations (5 ug/mL and 2.5 mg/mL respectively), but no interference at half these concentrations. All other substances showed no interference.
- Carryover Contamination:
- Study Type: Assessment of specimen and amplicon carryover.
- Sample Size: 2 GeneXpert modules run 20 times each, resulting in 40 positive and 42 negative samples.
- Key Results: No specimen or amplicon carry-over contamination was observed; all 40 positive samples correctly reported as SARS-CoV-2 POSITIVE and all 42 negative samples correctly reported as SARS-CoV-2 NEGATIVE.
- Reproducibility:
- Study Type: Multi-site reproducibility study in a CLIA-Waived environment.
- Sample Size: 3 sites x 3 operators x 1 lot x 5 days x 1 run x 2 replicates = 90 observations per panel member for each of 3 panel members (negative, low positive, moderate positive).
- Key Results: 100% agreement for qualitative results for negative, low positive, and moderate positive panel members across all sites and operators.
- Clinical Performance:
- Study Type: Multi-site, observational and method comparison study.
- Sample Size: 1783 specimens (883 NPS and 900 NS) with valid results.
- Key Metrics: PPA and NPA (see Key Metrics).
- Key Results: High PPA and NPA (see Key Metrics) demonstrated, showing substantial equivalence to the predicate device. Non-determinate rate was 0.7% (7/961) with NPS and 0.4% (4/973) with NS specimens.
Key Metrics
Clinical Performance:
- Positive Percent Agreement (PPA):
- Overall: 98.6% (95% CI: 96.0% - 99.5%)
- NPS: 98.2% (95% CI: 93.8% - 99.5%)
- NS: 99.0% (95% CI: 94.8% - 99.8%)
- Negative Percent Agreement (NPA):
- Overall: 99.1% (95% CI: 98.5% - 99.5%)
- NPS: 99.1% (95% CI: 98.1% - 99.6%)
- NS: 99.1% (95% CI: 98.2% - 99.6%)
- Non-determinate rate: 0.7% (7/961) with NPS and 0.4% (4/973) with NS specimens.
Reproducibility (Qualitative Results):
- Negative Sample: 100% Total Agreement (95% CI: 95.9% - 100%)
- SARS-CoV-2 Low Pos: 100% Total Agreement (95% CI: 95.9% - 100%)
- SARS-CoV-2 Mod Pos: 100% Total Agreement (95% CI: 95.9% - 100%)
Predicate Device(s)
Xpert Xpress CoV-2 plus (K230440)
Reference Device(s)
Not Found
Predetermined Change Control Plan (PCCP) - All Relevant Information
Not Found
§ 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.
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January 15, 2025
Cepheid Jennifer Motto Regulatory Affairs Principal 904 Caribbean Drive Sunnyvale, California 94089
Re: K242109
Trade/Device Name: Xpert Xpress CoV-2 plus Regulation Number: 21 CFR 866.3981 Regulation Name: 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 Regulatory Class: Class II Product Code: QQX
Dated: July 18, 2024 Received: July 19, 2024
Dear Jennifer Motto:
We have reviewed your section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (the Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
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Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).
Your device is also subject to, among other requirements, the Quality System (QS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30. Design controls; 21 CFR 820.90. Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review, the QS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safetyreporting-combination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.
All medical devices, including Class I and unclassified devices and combination product device constituent parts are required to be in compliance with the final Unique Device Identification System rule ("UDI Rule"). The UDI Rule requires, among other things, that a device bear a unique device identifier (UDI) on its label and package (21 CFR 801.20(a)) unless an exception or alternative applies (21 CFR 801.20(b)) and that the dates on the device label be formatted in accordance with 21 CFR 801.18. The UDI Rule (21 CFR 830.300(a) and 830.320(b)) also requires that certain information be submitted to the Global Unique Device Identification Database (GUDID) (21 CFR Part 830 Subpart E). For additional information on these requirements, please see the UDI System webpage at https://www.fda.gov/medical-device-advicecomprehensive-regulatory-assistance/unique-device-identification-system-udi-system.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.
For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatory
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assistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely, Anna M. Mielech -S
Anna Mielech, PhD. Deputy Branch Chief (Acting) Viral Respiratory and HPV Branch Division of Microbiology Devices OHT7: Office of In Vitro Diagnostics Office of Product Evaluation and Quality Center for Devices and Radiological Health Enclosure
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Indications for Use
510(k) Number (if known) K242109
Device Name Xpert Xpress CoV-2 plus
Indications for Use (Describe)
The Xpert Xpress CoV-2 plus test, performed on the GeneXpert Xpress System, is a rapid real-time RT-PCR test intended for the qualitative detection of SARS-CoV-2 RNA in nasopharyngeal and anterior nasal swab specimens collected from individuals with signs and symptoms of respiratory tract infection.
The Xpert Xpress CoV-2 plus test is intended for use as an aid in the diagnosis of COVID-19 if used in conjunction with other clinical, epidemiologic, and laboratory findings. Positive results are indicative of the presence of SARS-CoV-2 RNA. Positive results do not rule out bacterial infection or co-infection with other pathogens.
Negative results do not preclude SARS-CoV-2 infection. The results of this test should not be used as for diagnosis and patient management decisions.
Type of Use (Select one or both, as applicable)
☑ Prescription Use (Part 21 CFR 801 Subpart D) | ☐ Over-The-Counter Use (21 CFR 801 Subpart C) |
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Image /page/4/Picture/0 description: The image shows the Cepheid logo, which includes a blue graphic of three curved lines above the word "Cepheid." The text "Xpert® Xpress CoV-2 plus" is written below the logo. The "®" symbol is located to the upper right of the word "Xpert."
Dual 510(k) and CLIA Waiver by Application
510(k) Summary for Xpert Xpress CoV-2 plus
510(k) Summary
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TABLE OF CONTENTS
1 | 510(K) SUMMARY | 3 |
---|---|---|
1.1 | DEVICE DESCRIPTION | 4 |
1.2 | DEVICE INTENDED USE | 5 |
1.3 | SUBSTANTIAL EQUIVALENCE | 5 |
1.4 | PERFORMANCE STUDIES | 8 |
1.5 | CONCLUSIONS | 28 |
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1 510(k) Summary
As required by 21 CFR Section 807.92(c).
| Submitted by: | Cepheid
904 Caribbean Drive
Sunnyvale, CA 90489
Phone number: (408) 541-4191 |
|----------------------|---------------------------------------------------------------------------------------|
| Contact: | Jennifer Motto, M.S., RAC |
| Date of Preparation: | January 14, 2025 |
Device:
Trade name | Xpert® Xpress CoV-2 plus |
---|---|
Common name | Xpert Xpress CoV-2 plus |
Type of Test | Qualitative real-time reverse transcription polymerase chain reaction (RT-PCR) and detection test |
Regulation number: | 21 CFR 866.3981 |
Classification name: | Multi-target respiratory specimen nucleic acid test including SARS-CoV-2 and other microbial agents, |
Respiratory Specimen Nucleic Acid SARS-CoV-2 Test, | |
Primary Product code | QQX |
Secondary Product code | OOI |
Classification Advisory Panel | Microbiology (83) |
Prescription Use | Yes |
Predicate Device Assay: | Xpert Xpress CoV-2 plus (K230440) |
7
Device Description 1.1
The Xpert Xpress CoV-2 plus test is a rapid, automated in vitro diagnostic test for the qualitative detection of viral RNA from SARS-CoV-2 in nasopharyngeal swab (NPS) and anterior nasal swab (NS) specimens collected from individuals with signs and symptoms of respiratory tract infection.
The Xpert Xpress CoV-2 plus test is performed on GeneXpert Xpress System, which consist of a GeneXpert IV instrument that executes sample preparation, nucleic acid amplification and real-time fluorescent signal detection for the tests, and a GeneXpert Hub with preloaded GeneXpert Xpress software for running the tests and viewing the test results. The GeneXpert Hub accessory integrates the computer, touchscreen monitor and barcode scanner. Each of the GeneXpert modules in the GeneXpert IV instrument can perform independent sample preparation and testing. The GeneXpert Xpress System requires the use of single-use disposable cartridges that hold the RT-PCR reagents and host sample purification, nucleic acid amplification, and detection of the target sequences. Because the cartridges are selfcontained, cross-contamination between samples is minimized.
The Xpert Xpress CoV-2 plus test includes reagents for the detection of viral RNA from SARS-CoV-2 in NPS and NS specimens. The primers and probes in the Xpert Xpress CoV-2 plus test are designed to amplify and detect unique sequences in the genes that encode the following SARS-CoV-2 proteins: nucleocapsid (N2), envelope (E), and RNA-dependent RNA polymerase (RdRP). A Sample Processing Control (SPC) and a Probe Check Control (PCC) are also included in the cartridge serving as internal controls. The SPC is present to control for adequate processing of the sample and to monitor for the presence of potential inhibitor(s) in the RT-PCR reaction. The SPC also ensures that the RT-PCR reaction conditions (temperature and time) are appropriate for the amplification reaction and that the RT-PCR reagents are functional. The PCC verifies reagent rehydration, PCR tube filling, and confirms that all reaction components are present in the cartridge including monitoring for probe integrity and dye stability.
The Xpert Xpress CoV-2 plus test is designed for use with NPS or NS specimen collected with nylon flocked swabs and placed into viral transport medium (VTM), Universal Transport Medium (UTM) or eNAT®. Examples of the ancillary specimen collection kits that are compatible for use with the Xpert Xpress CoV-2 plus test include:
- Nasopharyngeal Sample Collection Kit for Viruses
- o Copan UTM® 3C057N (Flexible Minitip Flocked Swab with UTM® Medium w/o Beads)
8
- Becton Dickinson Universal Viral Transport Kit P/N 220531 (Flexible Minitip O Flocked Swab with UVT Medium)
- Copan eNAT® Molecular Collection and Preservation Medium P/N 6U074S01 o (Flexible Minitip Flocked Swab with eNAT® Medium)
Nasal Sample Collection Kit for Viruses ●
- Copan UTM® 3C064N (Regular Flocked Swab with UTM® Medium w/o O Beads)
- Copan eNAT® Molecular Collection and Preservation Medium P/N o 6U073S01 (Regular Flocked Swab with eNAT® Medium)
- Alternatively, swabs and transport media can be obtained separately: ●
- Nylon flocked swab (Copan P/N 502CS01, 503CS01) O
- Viral transport medium, 3 mL (Copan P/N 3C047N, BD Universal o Transport Medium, Remel M4RT, Remel M5)
These sample collection kits for viruses allow NPS and NS specimens from patients to be collected, preserved and transported to laboratory prior to analysis with the Xpert Xpress CoV-2 plus test.
1.2 Device Intended Use
The Xpert® Xpress CoV-2 plus test, performed on the GeneXpert® Xpress System, is a rapid real-time RT-PCR test intended for the qualitative detection of SARS-CoV-2 RNA in nasopharyngeal and anterior nasal swab specimens collected from individuals with signs and symptoms of respiratory tract infection.
The Xpert Xpress CoV-2 plus test is intended for use as an aid in the diagnosis of COVID-19 if used in conjunction with other clinical, epidemiologic, and laboratory findings. Positive results are indicative of the presence of SARS-CoV-2 RNA. Positive results do not rule out bacterial infection or co-infection with other pathogens.
Negative results do not preclude SARS-CoV-2 infection. The results of this test should not be used as the sole basis for diagnosis and patient management decisions.
1.3 Substantial Equivalence
Table 1 shows the similarities and differences between the subject device and the previously cleared predicate device [K230440].
9
Table 1. Comparison of Similarities and Differences Between Xpert Xpress CoV-2 plus and the | |||
---|---|---|---|
Predicate Device |
Subject Device | Predicate Device - K230440 | |
---|---|---|
Attribute | Xpert® Xpress CoV-2 plus, Performed | |
on the GeneXpert Xpress System | Xpert® Xpress CoV-2 plus, Performed | |
on the GeneXpert Instrument Systems | ||
Regulation | Same | 21 CFR 866.3981 |
Devices to detect and identify nucleic acid | ||
targets in respiratory samples from | ||
microbial agents that cause the SARS- | ||
CoV-2 respiratory infection and other | ||
microbial agents when in a multi-analyte | ||
test | ||
Product Code | Same | QQX |
Respiratory Specimen Nucleic Acid | ||
SARS-CoV-2 Test | ||
Device Class | Same | II (Special Controls) |
Technology/ | ||
Detection | Same | Real-time reverse transcription polymerase |
chain reaction (RT-qPCR) | ||
Intended Use | The Xpert Xpress CoV-2 plus test, | |
performed on the GeneXpert Xpress | ||
System, is a rapid real-time RT-PCR test | ||
intended for the qualitative detection of | ||
SARS-CoV-2 RNA in nasopharyngeal and | ||
anterior nasal swab specimens collected | ||
from individuals with signs and symptoms | ||
of respiratory tract infection. |
The Xpert Xpress CoV-2 plus test is
intended for use as an aid in the diagnosis
of COVID-19 if used in conjunction with
other clinical, epidemiologic, and
laboratory findings. Positive results are
indicative of the presence of SARS-CoV-2
RNA. Positive results do not rule out
bacterial infection or co-infection with
other pathogens.
Negative results do not preclude SARS-
CoV-2 infection. The results of this test
should not be used as the sole basis for
diagnosis and patient management
decisions. | The Xpert Xpress CoV-2 plus test,
performed on the GeneXpert Dx and
GeneXpert Infinity Systems, is a rapid
real-time RT-PCR test intended for the
qualitative detection of SARS-CoV-2
RNA in nasopharyngeal and anterior nasal
swab specimens collected from individuals
with signs and symptoms of respiratory
tract infection.
The Xpert Xpress CoV-2 plus test is
intended for use as an aid in the diagnosis
of COVID-19 if used in conjunction with
other clinical, epidemiologic, and
laboratory findings. Positive results are
indicative of the presence of SARS-CoV-2
RNA. Positive results do not rule out
bacterial infection or co-infection with
other pathogens.
Negative results do not preclude SARS-
CoV-2 infection. The results of this test
should not be used as the sole basis for
diagnosis and patient management
decisions. |
| Assay Targets | Same | SARS-CoV-2
(E, N2, RdRP) |
| Specimen Type | Same | Nasopharyngeal swab (NPS)
Anterior nasal swab (NS) |
| Transport
Media | Same | Universal Transport Medium
•
(UTM)/Viral Transport Medium
(VTM) |
| | Subject Device | Predicate Device – K230440 |
| Attribute | Xpert® Xpress CoV-2 plus, Performed
on the GeneXpert Xpress System | Xpert® Xpress CoV-2 plus, Performed
on the GeneXpert Instrument Systems |
| | | • eNAT |
| Test Format | Same | Single Use |
| Automation | Same | Automated Nucleic Acid Extraction,
Detection and Results Interpretation |
| Assay Results | Same | Qualitative |
| Internal
Control | Same | • Sample Processing Control (SPC)
• Probe Check Control (PCC) |
| Time to Result | Same | ~30 minutes |
| Instrument
Systems | Cepheid GeneXpert® Xpress System | Cepheid GeneXpert® Instrument Systems |
10
Image /page/10/Picture/0 description: The image contains the logo for Cepheid, a molecular diagnostics company. The logo features a stylized blue graphic above the company name, "Cepheid." Below the company name is the text "Xpert® Xpress CoV-2 plus", which likely refers to one of Cepheid's diagnostic tests. The text is in a smaller font size than the company name.
The following performance data (analytical and clinical) were provided in support of the substantial equivalence determination.
11
Performance Studies 1.4
1.4.1 Analytical Performance
Analytical Sensitivity/Limit of Detection (LoD) - Clinical NPS Matrix
The analytical sensitivity of the Xpert Xpress CoV-2 plus test was first estimated by testing limiting dilutions of a NATtrol inactivated SARS-CoV-2 virus in pooled negative clinical NPS-UTM/VTM matrix, using two reagent lots and following the guidance in Clinical and Laboratory Standards Institute (CLSI) document EP17-A2. LoD was estimated by considering each target gene (E, N2, and RdRP) in addition to the overall positivity rate for the Xpert Xpress CoV-2 plus test. The estimated LoD value as determined by Probit regression analysis was based on the weakest target gene (N2) and verified using two lots of Xpert Xpress CoV-2 plus reagents in replicates of 20 per lot for two clinical NPS matrices (UTM/VTM and eNAT). The concentration levels with observed hit rates greater than or equal to 95% in the LoD determination study were 403, 200 and 70 copies/mL for the N2 target, RdRP target, respectively. The claimed LoD is 403 copies/mL (Tables 2 and 3).
Table 2. Xpert Xpress CoV-2 plus Limit of Detection - Verification of NATtrol SARS-CoV-2 LoD in NPS-UTM/VTM Matrix
| Virus Strain | Reagent Lot | LoD
(copies/mL) | Positive
Results out
of # Valid
Replicates | %
Positive | Mean
E Ct | Mean
N2 Ct | Mean
RdRP Ct |
|------------------------|---------------|--------------------|-----------------------------------------------------|---------------|--------------|---------------|-----------------|
| NATtrol™
SARS-CoV-2 | Reagent Lot 1 | 403 | 20/20 | 100% | 34.3 | 38.3 | 36.6 |
| | Reagent Lot 2 | 403 | 20/20 | 100% | 34.1 | 37.7 | 36.5 |
Table 3. Xpert Xpress CoV-2 plus Limit of Detection - Verification of NATtrol SARS-CoV-2 LoD in NPS-eNAT Matrix
| Virus Strain | Reagent Lot | LoD
(copies/mL) | Positives
out of #
Valid
Replicates | %
Positive | Mean
E Ct | Mean
N2 Ct | Mean
RdRP Ct |
|--------------|---------------|--------------------|----------------------------------------------|---------------|--------------|---------------|-----------------|
| NATtrol™ | Reagent Lot 1 | 403 | 20/20a | 100% | 33.4 | 36.8 | 35.5 |
| SARS-CoV-2 | Reagent Lot 2 | 403 | 20/20 | 100% | 33.5 | 36.8 | 35.5 |
a. One of 20 replicates tested reported INVALID. The run was successfully repeated to obtain 20 valid replicates.
Analytical Sensitivity/Limit of Detection (LoD) - Clinical NS-UTM/VTM Matrix
The analytical sensitivity of the Xpert Xpress CoV-2 plus test was first estimated by testing limiting dilutions of a NATtrol inactivated SARS-CoV-2 virus in pooled negative clinical NS-UTM/VTM matrix, using two reagent lots and following the guidance in Clinical and Laboratory Standards Institute (CLSI) document EP17-A2. LoD was estimated by considering each target gene (E, N2, and RdRP) in addition to the overall positivity rate for the Xpert Xpress CoV-2 plus test. The LoD point estimates and 95% upper and lower
12
confidence intervals (CI) for individual SARS-CoV-2 targets (E, N2 and RdRP) in clinical NS-UTM/VTM matrix were determined using Probit regression analysis and the point estimated LoD values were 97, 462 and 157 copies/mL for the E target, N2 target and RdRP target, respectively. The estimated LoD value of the weakest target gene (N2) was verified using two lots of Xpert Xpress CoV-2 plus reagents in replicates of 20 per lot for clinical NS-UTM/VTM matrix. The claimed LoD is 462 copies/mL (Table 4).
Table 4. Xpert Xpress CoV-2 plus Limit of Detection - Verification of NATtrol SARS-CoV-2 LoD in NS-UTM/VTM Matrix
| Virus Strain | Reagent Lot | LoD
(copies/mL) | Positive
Results out
of # of
Valid
Replicates | %
Positive | Mean
E Ct | Mean
N2 Ct | Mean
RdRP Ct |
|------------------------|---------------|--------------------|-----------------------------------------------------------|---------------|--------------|---------------|-----------------|
| NATtrol™
SARS-CoV-2 | Reagent Lot 1 | 462 | 20/20 | 100% | 34.4 | 38.9 | 36.8 |
| | Reagent Lot 2 | 462 | 20/20 | 100% | 34.1 | 37.6 | 36.1 |
Analytical Sensitivity (Limit of Detection) - WHO First International Standard SARS-CoV-2 RNA in clinical NS-UTM/VTM matrix
The analytical sensitivity of the Xpert Xpress CoV-2 plus test was estimated by testing limiting dilutions of WHO First International Standard for SARS-CoV-2 RNA in pooled negative clinical NS-UTM/VTM matrix, using one reagent lot. The study was performed in a random and blinded fashion.
The lowest concentration level of the First WHO International Standard for SARS-CoV-2 RNA that generated ≥95% positive results (19/20 positive results) for the weakest target gene (N2) by the Xpert Xpress CoV-2 plus test was used to confirm the analytical sensitivity or Limit of Detection (LoD). The verified LoD for the First WHO International Standard for SARS-CoV-2 RNA tested in NS-UTM/VTM matrix with the Xpert Xpress CoV-2 plus test was 1000 IU/mL. The positivity rates for the overall SARS-CoV-2 results and the gene targets, including the mean Ct values for E, N2 and RdRP at the verified LoD are presented in Table 5.
Table 5. LoD Concentration, Positivity Rate and Mean Ct Values for SARS-CoV-2 for the First WHO International Standard for SARS-CoV-2 RNA in Clinical NS-UTM/VTM Matrix
SARS-CoV-2 | E Target | N2 Target | RdRP Target | |||||
---|---|---|---|---|---|---|---|---|
Virus | LoD | |||||||
Concentration | Positive | |||||||
Results / Test | ||||||||
Replicates | Positive Results | |||||||
/ Test | ||||||||
Replicates | Mean | |||||||
Ct | Positive Results | |||||||
/ Test | ||||||||
Replicates | Mean | |||||||
Ct | Positive Results | |||||||
/ Test | ||||||||
Replicates | Mean | |||||||
Ct | ||||||||
1st WHO | ||||||||
International | ||||||||
Standard for | ||||||||
SARS-CoV-2 | ||||||||
RNA Virus | 1000 IU/mL | 20/20 | 20/20 | 34.3 | 19/20 | 39.5 | 20/20 | 36.5 |
510(k) Summary
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Analytical Reactivity (Inclusivity)
SARS-CoV-2 in silico Analyses
The inclusivity of Xpert Xpress CoV-2 plus primers was initially evaluated on June 30, 2022 using in silico analysis of the assay amplicons in relation to 11,650,640 SARS-CoV-2 sequences available in the GISAID gene database for three targets, E, N2 and RdRP. The 11,650,640 SARS-CoV-2 sequences were separated into the lineages of interest based on the Pango Lineage assigned to each genome by GISAID, and those with ambiguous nucleotides were removed. Thus, the following inclusivity analyses focuses on the combined, nonambiguous sequences from the variants of interest and variants of concern as of June 30, 2022. These constituted 10,469,612 sequences for the E target, 10,587,381 sequences for the N2 target and 10,333,656 sequences for the RdRP target. Table 6 summarizes the effective predicted inclusivity for E, N2 and RdRP amplicons for the variants of interests and concern.
|--|
| SARS-CoV-2
Target Amplicon | Exact Match | 1 Mismatch a | 2 or More
Mismatches | Predicted
Inclusivity |
|-------------------------------|-------------------------------------------|-------------------|-------------------------|--------------------------|
| E | 10,420,248 of 10,469,612 total
(99.5%) | 48,562
(0.5%) | 802
(0.01%) | 100% |
| N2 | 10,386,068 of 10,587,381 total
(98.1%) | 196,336
(1.9%) | 4,977
(0.05%) | 99.95% |
| RdRP | 10,247,146 of 10,333,656 total
(99.2%) | 85,373
(0.8%) | 1,137
(0.01%) | 100% |
a. Single-nucleotide mismatches are predicted to not impact the performance of the test.
The in silico inclusivity of the Xpert Xpress CoV-2 plus probe oligonucleotides for E, N2 and RdRP were also assessed against the top 20 most frequent matches in the GISAID EpiCoV sequence database as of June 15, 2022, which constituted 10,310, 839 for the E target, 10,428,014 for the N2 target and 10,178,602 for the RdRP target. For each of the probe oligonucleotides used in the Xpert Xpress CoV-2 plus test, Table 7 summarizes the number sequences as well as the corresponding percentage of sequences from this dataset with exact match, 1 mismatch/insertion, and 2 or more mismatches/insertions in the alignment.
Table 7. Predicted Inclusivity for E, N2 and RdRP Probes for SARS-CoV-2 Variants of Interests and Concern
| SARS-CoV-2
Target Probe | Exact Match | 1 Mismatch/Insertion a | 2 or More
Mismatches/
Insertions | Predicted
Inclusivity |
|----------------------------|-------------------------------------------|------------------------------------------|----------------------------------------|--------------------------|
| E | 10,300,688 of 10,310,839 total
(99.9%) | 9,853
(0.1%) | 22
(0.0002%) | 100% |
| N2 | 10,351,581 of 10,428,014 total
(99.3%) | 72,957
(0.7%) | 0
(0%) | 100% |
| RdRP | 0 | 10,140,254 of 10,178602 total
(99.6%) | 37,492
(0.4%) | 99.6% |
Single-nucleotide mismatches/insertions are predicted to not impact the performance of the test. a.
14
In addition, the in silico inclusivity of the Xpert Xpress CoV-2 plus primer/probe sequences for E. N2 and RdRP was assessed against SAR-CoV-2 sequences submitted to the GISAID EpiCoV database up to 180 days prior to and including July 31, 2023 for SARS-CoV-2 isolates circulating in the United States. There were no instances where a specific primer/probe sequence was observed with greater than 0.5% frequency of mismatch during this 180-day period. The analysis predicted that the Xpert Xpress CoV-2 plus test will detect all circulating variants/lineages of SARS-CoV-2 evaluated during this 180-day period.
An updated inclusivity of Xpert Xpress CoV-2 plus was evaluated using in silico analysis of the assay amplicons and probes against the 2,691,091 SARS-CoV-2 sequences available in the GISAID gene database, for variants that are currently circulating, between August 1st 2022 and September 4th 2023 for three targets: E, N2 and RdRP.
The 2,691,091 SARS-CoV-2 sequences were separated into the lineages of interest based on the Pango Lineage assigned to each genome by GISAID, and those with ambiguous nucleotides were removed. Thus, the following inclusivity analyses focuses on the combined, non-ambiguous sequences from the variants of interest and variants of concern between August 1st 2022 and September 4th, 2023. These constituted 2,519,206 sequences for the E target, 2,551,690 sequences for the N2 target and 2,476,229 sequences for the RdRP target. Table 8 shows the number of sequences in each amplicon alignment and summarizes the effective predicted inclusivity for E, N2 and RdRP amplicons for the variants of interests and concern.
| SARS-CoV-2
Target
Amplicon | Exact Match | 1 Mismatch a | 2 or More
Mismatches | Predicted
Inclusivity |
|----------------------------------|-----------------------------------------|---------------|-------------------------|--------------------------|
| E | 2,503,319 of 2,519,206 total
(99.4%) | 15,694 (0.6%) | 193 (0.007%) | 100% |
| N2 | 2,495,212 of 2,551,690 total
(97.8%) | 55,765 (2.2%) | 713 (0.028%) | 99.95% |
| RdRP | 2,448,754 of 2,476,229 total
(98.9%) | 27,322 (1.1%) | 153 (0.006%) | 100% |
Table 8. Predicted Inclusivity for E, N2 and RdRP Amplicons for SARS-CoV-2 Variants of Interests and Concern
Single-nucleotide mismatches are predicted not to impact the performance of the test. a.
The in silico inclusivity of the Xpert Xpress CoV-2 plus probe oligonucleotides for E, N2 and RdRP was also assessed against the top 20 most frequent matches in the GISAID EpiCoV sequence database between August 1st 2022 and September 4th, 2023, which constituted 2,519,206 for the E target, 2,551,690 for the N2 target and 2,476,229 for the RdRP target. For each of the probe oligonucleotides used in the Xpert Xpress CoV-2 plus test. Table 9 summarizes the number sequences as well as the corresponding percentage of
15
sequences from this dataset with exact match, 1 mismatch/insertion, and 2 or more mismatches/insertions in the alignment.
| SARS-CoV-2
Target Probe | Exact Match | 1 Mismatch/Insertion ª | 2 or More
Mismatches/
Insertions | Predicted
Inclusivity |
|----------------------------|-----------------------------------------|--------------------------------------------|----------------------------------------|--------------------------|
| E | 2,516,153 of 2,519,206 total
(99.9%) | 2997
(0.1%) | 0
(0.0%) | 100% |
| N2 | 2,528,096 of 2,551,690 total
(99.1%) | 12728
(0.5%) | 0
(0%) | 99.6% |
| RdRP | 0 | 2,465,482 of 2,476,229
total
(99.6%) | 10418
(0.4%) | 99.6% |
Table 9. Predicted Inclusivity for E, N2 and RdRP Probes for SARS-CoV-2 Variants of Interests and Concern
Single-nucleotide mismatches/insertions are predicted to not impact the performance of the test. a.
Based on the built-in redundancy of the Xpert Xpress CoV-2 plus test's SARS-CoV-2 amplification system (i.e., 3 independent targets, only 1 of 3 must be detected to assign a positive result), it is not anticipated that any of the evaluated sequences would be missed by the Xpert Xpress CoV-2 plus test.
SARS-CoV-2 Wet-Testing
In addition to the in silico analysis of the SARS-CoV-2 primers and probes for inclusivity, the inclusivity of the Xpert Xpress CoV-2 plus test was evaluated by bench testing against multiple strains of SARS-CoV-2 at levels near the analytical LoD (~3x LoD). A total of 61 strains comprised of 23 intact SARS-CoV-2 viral particles (18 inactivated viral cultures and 5 BSL-3 live viral cultures), and 38 SARS-CoV-2 in vitro RNA transcripts representing variant strains were tested in this study with the Xpert Xpress CoV-2 plus test. Three replicates were tested for each strain. All SARS-CoV-2 strains tested positive in all three replicates. Results are shown in Table 10.
| Count
No. | SARS-CoV-2 Strain | Tested
Concentration | SARS-CoV-2
Test Results | Number of Positive Results
Obtained out of the Total
Number of Valid Replicates | | |
|--------------|-------------------------------------------------|--------------------------------|----------------------------|---------------------------------------------------------------------------------------|-----|------|
| | | | | E | N2 | RdRP |
| 1 | 2019-nCoV/Italy-INMI1 a | 5 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 2 | England/204820464/2020 a | 0.5 TCID50/mL | POS e | 3/3 | 3/3 | 3/3 |
| 3 | Hong Kong/VM20001061/2020 a | 0.25 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 4 | South Africa/KRISP-
K005325/2020 a | 0.25 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| Count
No. | SARS-CoV-2 Strain | Tested
Concentration | SARS-CoV-2
Test Results | Number of Positive Results
Obtained out of the Total
Number of Valid Replicates | | |
| | | | | E | N2 | RdRP |
| 5 | USA/CA_CDC_5574/2020 ª | 0.25 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 6 | USA/MD-HP01542/2021 ª | 1.3e3 genome
equivalents/mL | POS | 3/3 | 3/3 | 3/3 |
| 7 | USA/GA-EHC-2811C/2021 ª | 1.3e3 genome
equivalents/mL | POS | 3/3 | 3/3 | 3/3 |
| 8 | NY-Wadsworth-103677-01/2020 ª | 0.15 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 9 | NY-Wadsworth-21006055-
01/2021 a | 0.04 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 10 | NY-Wadsworth-21025952-
01/2021 ª (Isolate 1) | 0.625 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 11 | NY-Wadsworth-21018781-
01/2021 ª (Isolate 2) | 0.625 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 12 | NY-Wadsworth-21033899-
01/2021 ª | 1.25 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 13 | NY-Wadsworth-33126-01/2020 ª | 0.15 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 14 | USA/CA-Stanford-15_S02/2021ª | 0.04 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 15 | USA/PHC658/2021ª | 25 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 16 | Japan/TY7-503/2021ª | 0.75 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 17 | hCoV-19/USA/MD-
HP30386/2022 ª | 27.5 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 18 | hCoV-19/USA/COR-22-
063113/2022 a | 19 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 19 | Australia/VIC01/2020 b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 20 | Belgium/ULG/10004/2020 b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 21 | England/205041766/2020 b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 22 | England/MILK-9E05B3/2020 b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 23 | England/SHEF-C05B2/2020 b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 24 | France/HF2393/2020 b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 25 | Hong Kong/HKU-211129-
001/2021 b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 26 | Iceland/5/2020 b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 27 | India/CT-ILSGS00361/2021 b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 28 | India/MH-NCCS-
P1162000182735/2021 b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 29 | India/MH-SEQ-
221 S66 R1 001/2021 b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 30 | Japan/Hu_DP_Kng_19-020/2020 b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 31 | Japan/IC-0564/2021 b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 32 | Portugal/PT9543/2021b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| Count
No. | SARS-CoV-2 Strain | Tested
Concentration | SARS-CoV-2
Test Results | Number of Positive Results
Obtained out of the Total
Number of Valid Replicates | | |
| | | | | E | N2 | RdRP |
| 33 | South Africa/KRISP-EC-
K005299/2020 b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 34 | Taiwan/NTU02/2020b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 35 | USA/CA9/2020b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 36 | USA/CA-PC101P/2020b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 37 | USA/CA-CZB-12943/2020b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 38 | USA/MN2-MDH2/2020b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 39 | USA/NY-MSHSPSP-
PV24650/2020b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 40 | USA/TX1/2020b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 41 | USA/WA2/2020b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 42 | USA/WA-CDC-
UW21061750277/2021b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 43 | Wuhan-Hu-1b | 1.2e3 copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 44 | Germany/BavPat1/2020c | 1.2e3 genome
copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 45 | Singapore/2/2020c | 300 genome
equivalents/mL | POS | 3/3 | 3/3 | 3/3 |
| 46 | USA/AZ1/2020c | 300 genome
equivalents/mL | POS | 3/3 | 3/3 | 3/3 |
| 47 | USA/CA1/2020c | 1.2e3 genome
equivalents/mL | POS | 3/3 | 3/3 | 3/3 |
| 48 | USA/CA2/2020c | 1.2e3 genome
equivalents/mL | POS | 3/3 | 3/3 | 3/3 |
| 49 | USA/CA3/2020c | 400 genome
equivalents/mL | POS | 3/3 | 3/3 | 3/3 |
| 50 | USA/CA4/2020c | 1.2e3 genome
equivalents/mL | POS | 3/3 | 3/3 | 3/3 |
| 51 | USA/IL1/2020c | 150 genome
equivalents/mL | POS | 3/3 | 3/3 | 3/3 |
| 52 | USA/New York-PV08001/2020c | 1.2e3 genome
copies/mL | POS | 3/3 | 3/3 | 3/3 |
| 53 | USA/New York-PV08410/2020c | 300 genome
equivalents/mL | POS | 3/3 | 3/3 | 3/3 |
| 54 | USA/New York-PV08449/2020c | 300 genome
equivalents/mL | POS | 3/3 | 3/3 | 3/3 |
| 55 | USA/New York-PV09158/2020c | 300 genome
equivalents/mL | POS | 3/3 | 3/3 | 3/3 |
| 56 | USA/WI1/2020c | 1.2e3 genome
equivalents/mL | POS | 3/3 | 3/3 | 3/3 |
| 57 | hCoV-19/USA/MD-
HP38861/2022 d | 0.29 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| Count
No. | SARS-CoV-2 Strain | Tested
Concentration | SARS-CoV-2
Test Results | Number of Positive Results
Obtained out of the Total
Number of Valid Replicates | | |
| | | | | E | N2 | RdRP |
| 58 | hCoV-19/USA/MD-
HP38960/2022 d | 0.043 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 59 | hCoV-19/USA/CO-CDPHE-
2102544747/2021 d | 0.028 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 60 | hCoV-19/USA/MD-
HP38288/2022 d | 0.24 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
| 61 | hCoV-19/USA/MD-
HP40900/2022 d | 0.72 TCID50/mL | POS | 3/3 | 3/3 | 3/3 |
16
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Dual 510(k) and CLIA Waiver by Application
510(k) Summary
17
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Dual 510(k) and CLIA Waiver by Application
18
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Inactivated viral culture fluid (intact viral particles) a.
b. Synthetic, in vitro RNA transcript, TWIST controls
c. Genomic RNA
BSL-3 live viral culture fluid (intact viral particles) d.
One of 3 replicates reported ERROR. The run was successfully repeated to obtain 3 valid replicates. e.
Analytical Specificity (Exclusivity)
In Silico Analyses
The analytical specificity/cross-reactivity of the Xpert Xpress CoV-2 plus included an evaluation of the SARS-CoV-2 test primer and probes with potentially cross-reactive microorganisms by in silico analysis was conducted by mapping the primers and probes of Xpert Xpress CoV-2 plus individually to the microorganism sequences downloaded from the NCBI database. E primers and probes are not specific for SARS-COV-2 and will detect Human and Bat SARS-coronavirus. No potential unintended cross reactivity with other organisms listed in Table 11 is expected based on the in silico analysis.
Table 11. Microorganisms Analyzed in the in silico Analysis for the SARS-CoV-2 Target
| Microorganisms from the Same Genetic
Family | High Priority Organisms |
---|---|
Human coronavirus 229E | Adenovirus (e.g., C1 Ad. 71) |
Human coronavirus OC43 | Cytomegalovirus |
Human coronavirus HKU1 | Enterovirus (e.g., EV68) |
Human coronavirus NL63 | Epstein-Barr virus |
SARS-coronavirus | Human Metapneumovirus (hMPV) |
MERS-coronavirus | Influenza A & B |
Bat coronavirus | Measles |
Mumps | |
Parainfluenza virus 1-4 | |
Parechovirus | |
Respiratory syncytial virus | |
Rhinovirus | |
Bacillus anthracis (Anthrax) |
19
| Microorganisms from the Same Genetic
Family | High Priority Organisms |
---|---|
Bordetella pertussis | |
Bordetella parapertussis | |
Chlamydia pneumoniae | |
Chlamydia psittaci | |
Corynebacterium diphtheriae | |
Coxiella burnetii (Q-Fever) | |
Escherichia coli | |
Fusobacterium necrophorum | |
Haemophilus influenzae | |
Lactobacillus sp. | |
Legionella non-pneumophila | |
Legionella pneumophila | |
Leptospira | |
Moraxella catarrhalis | |
Mycobacterium tuberculosis | |
Mycoplasma genitalium | |
Mycoplasma pneumoniae | |
Neisseria elongata | |
Neisseria meningitidis | |
Pneumocystis jirovecii (PJP) | |
Pseudomonas aeruginosa | |
Staphylococcus aureus | |
Staphylococcus epidermidis | |
Staphylococcus salivarius | |
Streptococcus pneumoniae | |
Streptococcus pyogenes | |
Aspergillus sp | |
Candida albicans |
Wet-Testing
In addition to the in silico analysis of the SARS-CoV-2 primers and probes for crossreactivity, the analytical specificity of the Xpert Xpress CoV-2 plus test was evaluated by bench-testing a panel of 62 microorganisms comprising (4) human coronaviruses, (1) MERScoronavirus, (1) SARS-coronavirus, (20) other respiratory viruses, (30) respiratory bacteria, (2) yeast strains, (3) fungal strain, and 1 human nasal wash fluid representing diverse microbial flora in the human respiratory tract.
The intact viruses were tested at concentrations of ≥105 TCID50/mL, ≥105 CEID50/mL, and ≥105 copies/mL. Bacteria and yeast were tested at ≥10° CFU/mL. The bacteria Chlamydia pneumoniae and Mycoplasma pneumoniae were tested at concentrations of ≥10° IFU/mL and
20
106 CCU/mL, respectively. Live strains of Coxiella burnetii, Lactobacillus reuteri, and Neisseria meningitides were not available, therefore genomic DNA at > 10% genome equivalent copies/mL was used. The in vitro transcribed (IVT) RNA sample was tested at ≥ 10° genome equivalent/mL for human Coronavirus HKU1, and the genomic RNA sample was tested at ≥ 10° genome equivalent/mL for SARS-coronavirus Urbani.
The microorganisms being evaluated for cross-reactivity were tested in groups or individually and spiked into negative simulated NPS/NS background matrix for testing. If a grouped microorganisms produced a SARS-CoV-2 positive result, then each member of the group was tested separately. If the individual non-target organism yielded a positive result, retesting was performed at lower concentrations until a concentration that no longer produce a false positive result was identified.
The results of the analytical specificity/exclusivity study demonstrate that the primer/probe sets included in the Xpert Xpress CoV-2 plus does not cross-react with the nucleic acids from non-intended respiratory microorganisms and phylogenetically related human coronavirus species. The one exception was the SARS-coronavirus, Urbani, which yielded the expected test result of SARS-CoV-2 POSITIVE. We expected cross-reactivity for the E gene target with the SARS-coronavirus Urbani strain which has the highly conserved E gene target shared among coronaviruses in the B lineage Betacoronavirus. Results are shown in Table 12.
21
| Respiratory Microorganisms | Test
Group | Tested
Concentration | Final
SARS-
CoV-2
Result
Call-Out | Number of Positive Results
Obtained from Total
Number of Replicates
Tested | | |
|--------------------------------------------------------------|---------------|-------------------------|-----------------------------------------------|-------------------------------------------------------------------------------------|-----|------|
| | | | | E | N2 | RdRP |
| Human coronavirus, 229E | | 1.1e5 TCID50/mL | | | | |
| Human coronavirus, OC43 | G1 | 1.1e5 TCID50/mL | NEG | 0/3 | 0/3 | 0/3 |
| MERS-coronavirus | | 1.1e5 TCID50/mL | | | | |
| Human coronavirus, NL63 | G2 | 1.1e5 TCID50/mL | NEG | 0/3 | 0/3 | 0/3 |
| Human coronavirus, HKU1a | G3 | 1.1e6 genome cp/mL | NEG | 0/3 | 0/3 | 0/3 |
| SARS-coronavirus, Urbani a | G4 | 1.1e6 genome cp/mL | POS | 3/3 | 0/3 | 0/3 |
| Influenza A H1N1 (pdm2009),
Michigan/272/2017 | | 1.1e5 TCID50/mL | | | | |
| Influenza B (Victoria Lineage),
Hawaii/01/2018 (NA D197N) | G5 | 1.1e5 TCID50/mL | NEG | 0/3 | 0/3 | 0/3 |
| RSV-A, Strain: 4/2015 Isolate #1 | | 1.1e5 TCID50/mL | | | | |
| Adenovirus Type 1 | | 1.1e5 TCID50/mL | | | | |
| Adenovirus Type 7A | G6 | 1.1e5 TCID50/mL | NEG | 0/3 | 0/3 | 0/3 |
| Cytomegalovirus | | 1.1e5 TCID50/mL | | | | |
| Echovirus | | 1.1e5 TCID50/mL | | | | |
| Enterovirus, D68 strain US/KY/14-
18953 | | 1.1e5 TCID50/mL | | | | |
| Epstein Barr Virus (Human Herpes
Virus 4 [Hhv-4]) | | 1.1e5 cp/mL | NEG | 0/3 | 0/3 | 0/3 |
| Herpes Simplex Virus (HSV) type 1 | G7 | 1.1e5 TCID50/mL | | | | |
| Human metapneumovirus
(hMPV-5, type B1) | | 1.1e5 TCID50/mL | | | | |
| Measles | | 1.1e5 TCID50/mL | | | | |
| Mumps virus | | 1.1e5 TCID50/mL | | | | |
| Human parainfluenza Type 1 | | 1.1e5 TCID50/mL | | | | |
| Human parainfluenza Type 2 | | 1.1e5 TCID50/mL | | | | |
| Human parainfluenza Type 3 | G8 | 1.1e5 TCID50/mL | NEG | 0/3 | 0/3 | 0/3 |
| Human parainfluenza Type 4 | | 1.1e5 TCID50/mL | | | | |
| Rhinovirus, Type 1A b | | 4.5e4 TCID50/mL | | | | |
| Acinetobacter baumannii | | 1.1e6 CFU/mL | | | | |
| Burkholderia cepacia | G9 | 1.1e6 CFU/mL | NEG | 0/3 | 0/3 | 0/3 |
| Candida albicans | | 1.1e6 CFU/mL | | | | |
| Respiratory Microorganisms | Test
Group | Tested
Concentration | Final
SARS-
CoV-2
Result
Call-Out | Number of Positive Results
Obtained from Total
Number of Replicates
Tested | | |
| | | | | E | N2 | RdRP |
| Candida parapsilosis | | 1.1e6 CFU/mL | | | | |
| Bordetella pertussis | | 1.1e6 CFU/mL | | | | |
| Chlamydia pneumoniae | | 1.1e6 IFU/mL | | | | |
| Citrobacter freundii | | 1.1e6 CFU/mL | | | | |
| Corynebacterium xerosis | | 1.1e6 CFU/mL | | | | |
| Escherichia coli | | 1.1e6 CFU/mL | NEG | 0/3 | 0/3 | 0/3 |
| Enterococcus faecalis | G10 | 1.1e6 CFU/mL | | | | |
| Hemophilus influenzae | | 1.1e6 CFU/mL | | | | |
| Legionella spp. d | | 1.1e6 CFU/mL | | | | |
| Moraxella catarrhalis | | 1.1e6 CFU/mL | | | | |
| Mycobacterium tuberculosis
(avirulent) | | 1.1e6 CFU/mL | NEG | 0/3 | 0/3 | 0/3 |
| Mycoplasma pneumoniae | | 1.1e6 CCU/mL | | | | |
| Neisseria mucosa | G11 | 1.1e6 CFU/mL | | | | |
| Propionibacterium acnes (=
Cutibacterium acnes) Z144 | | 1.1e6 CFU/mL | | | | |
| Pseudomonas aeruginosa, Z139 | | 1.1e6 CFU/mL | | | | |
| Staphylococcus aureus | | 1.1e6 CFU/mL | | | | |
| Staphylococcus epidermidis | | 1.1e6 CFU/mL | NEG | 0/3 | 0/3 | 0/3 |
| Staphylococus haemolyticus | | 1.1e6 CFU/mL | | | | |
| Streptococcus agalactiae | | 1.1e6 CFU/mL | | | | |
| Streptococcus pneumoniae | | 1.1e6 CFU/mL | | | | |
| Streptococcus pyogenes | G12 | 1.1e6 CFU/mL | | | | |
| Streptococcus salivarius | | 1.1e6 CFU/mL | | | | |
| Streptococcus sanguinis | | 1.1e6 CFU/mL | | | | |
| Pneumocystis jirovecii (PJP) | | 1.1e6 CFU/mL | | | | |
| Lactobacillus reuteri, F275 c | G13 | 1.1e6 genome cp/mL | NEG | 0/3 | 0/3 | 0/3 |
| Neisseria meningitides c | | 1.1e6 genome cp/mL | | | | |
| Pooled human nasal wash | G14 | N/A | NEG | 0/3 | 0/3 | 0/3 |
| Influenza C (Taylor/1233/1947) | G15 | 1.1e5 CEID50/mL | NEG | 0/3 | 0/3 | 0/3 |
| Rhinovirus, Type 1Ab | G16 | 1.1e5 TCID50/mL | NEG | 0/3 | 0/3 | 0/3 |
| Aspergillus flavus | G17 | 1.35e7 CFU/mL | NEG | 0/3 | 0/3 | 0/3 |
| Aspergillus fumigatus | G18 | 3.67e6 CFU/mL | NEG | 0/3 | 0/3 | 0/3 |
| Respiratory Microorganisms | Test
Group | Tested
Concentration | Final
SARS-
CoV-2
Result
Call-Out | Number of Positive Results
Obtained from Total
Number of Replicates
Tested | | |
| | | | | E | N2 | RdRP |
| Coxiella burnetii c | G19 | 2.5e6 genome cp/mL | NEG | 0/3 | 0/3 | 0/3 |
| Leptospira broomii | G20 | 2.9e6 CFU/mL | NEG | 0/3 | 0/3 | 0/3 |
| Parechovirus type 1 | G21 | 3.39e5 TCID50/mL | NEG | 0/3 | 0/3 | 0/3 |
| Fusobacterium necrophorum | G22 | 6.52e6 CFU/mL | NEG | 0/3 | 0/3 | 0/3 |
| Mycoplasma genitalium c | G23 | 3.6e6 genome cp/mL | NEG | 0/3 | 0/3 | 0/3 |
Table 12. Analytical Specificity (Exclusivity) of the Xpert Xpress CoV-2 plus Test
22
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Dual 510(k) and CLIA Waiver by Application
23
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Microorganism in the form of genomic RNA were tested in Tris-EDTA+ ([NH4]>SQ4] buffer using an assay a. definition file (ADF) without sample preparation.
Rhinovirus, Type 1A was initially tested at 4.5 e4 TCID50/mL in test group G8 using virus lot 325725. It was b. re-tested individually (G16) at a higher concentration of 1.1e5 TCID50/mL using virus lot 326527.
Microorganisms in the form of genomic DNA were tested in simulated NPS/NS background matrix using the C. ADF with full sample preparation.
Legionella pneumophila was tested in this study. d.
Microbial Interference
A microbial interference study was performed to assess the inhibitory effects of commensal microorganisms potentially encountered in upper respiratory tract specimens on the performance of the Xpert Xpress CoV-2 plus test. A panel of 18 commensal microorganisms, consisting of 15 viral strains and 3 bacterial strains was tested. Contrived samples consisted of SARS-CoV-2 virus seeded at 1.15x-3x LoD into simulated nasopharyngeal swab (NPS)/ anterior nasal swab (NS) matrix in the presence of commensal virus and bacterial strains spiked at their respective concentrations listed in Table 13.
Replicates of 8 positive samples were tested with SARS-CoV-2 virus and each potential microbial interference strain combination. All 8 of 8 positive replicate samples were correctly identified as SARS-CoV-2 POSITIVE using the Xpert Xpress CoV-2 plus test. No interference by the listed above commensal viral or bacterial strains was reported at the concentrations tested.
| Commensal Strain | Concentration Tested | Number of Correct
Test Results/
Number Tested |
|-------------------------|----------------------|-----------------------------------------------------|
| Adenovirus Type 1Ca | 1x105 TCID50/mL | 8/8 |
| Adenovirus Type 2Cb | 1x105 TCID50/mL | 8/8c |
| Adenovirus Type 3Bb | 1x105 TCID50/mL | 8/8 |
| Human Coronavirus-OC43a | 1x105 copies/mL | 8/8 |
Table 13: Microbial Interference Study Results
24
| Commensal Strain | Concentration Tested | Number of Correct
Test Results/
Number Tested |
|--------------------------------|----------------------|-----------------------------------------------------|
| Human Coronavirus-229Eb | 1x105 TCID50/mL | 8/8 |
| Human Coronavirus-NL63b | 1x105 TCID50/mL | 8/8 |
| Human Coronavirus-HKU1b | 1x105 copies/mL | 8/8 |
| Metapneumovirus 5, Type B1a | 1x105 TCID50/mL | 8/8 |
| Parainfluenza Type 1a | 1x105 TCID50/mL | 8/8 |
| Parainfluenza Type 2a | 1x105 TCID50/mL | 8/8 |
| Parainfluenza Type 3a | 1x105 TCID50/mL | 8/8 |
| Rhinovirus Type 1Aa | 1x105 PFU/mL | 8/8 |
| Influenza A H1N1b | 1x105 CEID50/mL | 8/8 |
| Influenza Bb | 1x105 TCID50/mL | 8/8d |
| Respiratory Syncytial Virus Ab | 1x105 TCID50/mL | 8/8 |
| Haemophilus influenzaea | 1x107 CFU/mL | 8/8 |
| Staphylococcus aureusa | 1x107 CFU/mL | 8/8 |
| Staphylococcus epidermidisa | 1x107 CFU/mL | 8/8 |
a. These commensal strains were tested with SARS-CoV-2 at a concentration of 3x LoD.
b. These commensal strains were tested with SARS-CoV-2 at a concentration of 1.15x LoD.
c. Two of 8 replicates reported as ERROR. The runs were successfully repeated to obtain 8 valid replicates.
d. One of 8 replicates reported as ERROR. The run was successfully repeated to obtain 8 valid replicates.
Potentially Interfering Substances
Substances that could be present in the nasopharynx (or introduced during specimen collection and handling) and potentially interfere with accurate detection of SARS-CoV-2 were evaluated with direct testing on the Xpert Xpress CoV-2 plus test. Potentially interfering substances in the nasal passage and nasopharynx may include, but are not limited to: blood, nasal secretions or mucus, and nasal and throat medications (used to relieve congestion, nasal dryness, irritation, or asthma and allergy symptoms), as well as antibiotics and antivirals. Positive and negative samples were prepared in simulated nasopharyngeal swab (NPS)/ anterior nasal swab (NS) matrix. Negative samples (N = 8) were tested in the presence of each substance to determine the effect on the performance of the sample processing control (SPC). Positive samples (N = 8) were tested per substance with SARS-CoV-2 virus spiked at 3x LoD. The controls were samples with and without SARS-CoV-2 virus spiked at 3x LoD into simulated NPS/ NS matrix containing no potentially interfering substance.
The 23 potentially interfering substances, with active ingredients, that were evaluated are listed in Table 14. For substances that resulted in an INVALID test result, the concentration of the substance was reduced by half and re-tested. Interfering effects were observed for fluticasone propionate and mucin type I-S.
25
Substance ID | Substance/Class | Substance/Active Ingredient | Concentrations Tested |
---|---|---|---|
No substance | Control | Simulated NPS/NS Matrix | 100% (v/v) |
Afrin | Nasal Spray | Oxymetazoline (0.05%) | 15% (v/v) |
Albuterol Sulfate | Beta-adrenergic | ||
bronchodilator | Albuterol Sulfate (5mg/mL) | 0.83 mg/mL | |
(equivalent to 1 dose per day) | |||
BD Universal | |||
Transport Medium | Transport Media | BD Universal Transport Medium | 100% (v/v) |
Blood | Blood | Blood (Human) | 2% (v/v) |
Copan Swab M | Transport Media | Copan Swab M | 100% (v/v) |
FluMist | FluMist® | Live intranasal influenza | |
virus vaccine | 6.7% (v/v) | ||
Fluticasone | |||
Propionate Nasal | |||
Spray | Nasal corticosteroid | Fluticasone Propionate | 5 µg/mL, 2.5 µg/mL |
Ibuprofen | Analgesic | ||
(nonsteroidal anti- | |||
inflammatory drugs | |||
(NSAID)) | Ibuprofen | 21.9 mg/dL | |
Leukocytes | Leukocytes | Leukocytes (Human) | 1 x 106 cells/mL |
Menthol | Throat lozenges, oral | ||
anesthetic, and | |||
analgesic | Benzocaine, Menthol | 1.7 mg/mL | |
Mucin type II | Mucin | Purified Mucin protein | |
(Porcine submaxillary | |||
gland, type II) | 0.1% (w/v) | ||
Mucin type I-S | Mucin | Purified Mucin protein | |
(Bovine submaxillary gland, | |||
type I-S) | 2.5 mg/mL, 1.25 mg/mL | ||
Mupirocin | Antibiotic, nasal | ||
ointment | Mupirocin (2%) | 10 mg/mL | |
Human peripheral | |||
blood mononuclear | |||
cells (PBMC) | Human peripheral | ||
blood mononuclear | |||
cells (PBMC) | Human peripheral blood | ||
mononuclear cells (PBMC) | 1x103 cells/µL | ||
PHNY | Nasal Drops | Phenylephrine (1%) | 15% (v/v) |
Remel M4RT | Transport Media | Remel M4RT | 100% (v/v) |
Remel M5 | Transport Media | Remel M5 | 100% (v/v) |
Saline | Saline Nasal Spray | Sodium Chloride (0.65%) | 15% (v/v) |
Snuff | Tobacco | Nicotine | 1% (w/v) |
Tamiflu | Anti-viral drugs | Zanamivir | 7.5 mg/mL |
Tobramycin | Antibacterial, systemic | Tobramycin | 4 µg/mL |
Zicam | Nasal Gel | Luffa opperculata, | |
Galphimia glauca, | |||
Histaminum | |||
hydrochloricum Sulfur | |||
(0.05%) | 15% (w/v) |
Table 14. Potentially Interfering Substances Tested | ||
---|---|---|
26
The results for the negative and positive samples are presented in Table 15.
The results from the SARS-CoV-2 negative samples showed that in the presence of fluticasone propionate nasal spray at 5 µg/mL and mucin type I-S at 2.5 mg/mL, 7 of 8 replicates correctly reported "SARS-CoV-2 NEGATIVE" test results, and 1 of 8 replicates reported "INVALID" test result for each substance. When the concentrations of fluticasone propionate nasal spray and mucin type I-S were reduced by half, 8/8 replicates provided valid test results and correctly reported "SARS-CoV-2 NEGATIVE" for each substance. No interference was observed at these lower concentrations.
The results from the SARS-CoV-2 positive samples showed that in the presence of fluticasone propionate nasal spray at 5 ug/mL, 7 of 8 replicates correctly reported "SARS-CoV-2 POSITIVE" test results and 1 of 8 replicate reported "INVALID" test result. When the concentration of the fluticasone propionate nasal spray was reduced to 2.5 us/mL, 8/8 replicates provided valid test results and correctly reported "SARS-CoV-2 POSITIVE". No interference was observed at this lower concentration.
| Substance | Concentration Tested | Number SARS-CoV-2
Negative / Number of
Valid Replicates Tested | Number SARS-CoV-2
Positive / Number of
Valid Replicates Tested |
|-------------------------------------------------------|------------------------|----------------------------------------------------------------------|----------------------------------------------------------------------|
| SARS-CoV-2 Negative
(No Substance) Control | 100% (v/v) | 8/8 | Not Applicable |
| SARS-CoV-2 Positive
(No Substance) Control | 100% (v/v) | Not Applicable | 8/8 |
| Afrin | 15% (v/v) | 8/8 | 8/8 |
| Albuterol Sulfate | 0.83 mg/mL | 8/8 | 8/8 |
| BD Universal Transport
Medium | 100 (v/v) | 8/8 | 8/8 |
| Blood | 2% (v/v) | 8/8 | 8/8 |
| Copan Swab M | 100 (v/v) | 8/8 | 8/8 |
| FluMist® | 6.7% (v/v) | 8/8 | 8/8 |
| Fluticasone Propionate | 5 $\mu$ g/mL | 7/8a | 7/8a |
| Nasal Spray | 2.5 $\mu$ g/mL | 8/8 | 8/8 |
| Ibuprofen | 21.9 mg/dL | 8/8 | 8/8 |
| Leukocytes | 1 x 106 cells/mL | 8/8 | 8/8 |
| Menthol | 1.7 mg/mL | 8/8 | 8/8 |
| Mucin (Type II) | 0.1% (w/v) | 8/8 | 8/8 |
| Mucin (Type I-S) | 2.5 mg/mL | 7/8a | 8/8 |
| | 1.25 mg/mL | 8/8 | Not Applicable |
| Mupirocin | 10 mg/mL | 8/8 | 8/8 |
| Human Peripheral Blood
Mononuclear Cells
(PBMC) | 1 x 103 cells/ $\mu$ L | 8/8 | 8/8 |
| PHNY | 15% (v/v) | 8/8 | 8/8 |
Table 15. SARS-CoV-2 Negative Samples Tested in the Presence of Potentially Interfering Substances
510(k) Summary
27
| Substance | Concentration Tested | Number SARS-CoV-2
Negative / Number of
Valid Replicates Tested | Number SARS-CoV-2
Positive / Number of
Valid Replicates Tested |
|------------|----------------------|----------------------------------------------------------------------|----------------------------------------------------------------------|
| Remel M4RT | 100% (v/v) | 8/8 | 8/8 |
| Remel M5 | 100% (v/v) | 8/8 | 8/8 |
| Saline | 15% (v/v) | 8/8 | 8/8 |
| Snuff | 1% (w/v) | 8/8 | 8/8 |
| Tamiflu | 7.5 mg/mL | 8/8 | 8/8 |
| Tobramycin | 4 $\mu$ g/mL | 8/8 | 8/8 |
| Zicam | 15% (w/v) | 8/8 | 8/8 |
| Zinc | 0.1 $\mu$ g/mL | 8/8 | 8/8 |
a. One of 8 replicates reported INVALID test result, indicating interference from the substance was subsequently tested with 8 replicates at half the initial concentration.
Carryover Contamination
A study was conducted to assess whether the single-use, self-contained Xpert Xpress CoV-2 plus cartridge prevents specimen and amplicon carryover by testing a negative sample immediately after testing of a very high positive sample in the same GeneXpert module. The negative sample used in this study consisted of simulated NPS/NS matrix and the positive sample consisted of high SARS-CoV-2 virus concentration (inactivated SARS-CoV-2 USA-WA1/2020 at 5e4 copies/mL) spiked into negative NPS/NS matrix. The negative sample was tested in a GeneXpert module at the start of the study. Following the initial testing of the negative sample, the high positive sample was processed in the same GeneXpert module immediately followed by another negative sample. This was repeated 20 times in the same module, resulting in 20 positives and 21 negatives for the module. The study was repeated using a second GeneXpert module for a total of 40 positive and 42 negative samples. All 40 positive samples were correctly reported as SARS-CoV-2 POSITIVE and all 42 negative samples were correctly reported as SARS-CoV-2 NEGATIVE with the Xpert Xpress CoV-2 plus test. No specimen or amplicon carry-over contamination was observed in this study.
Reproducibility
The reproducibility of the Xpert Xpress CoV-2 plus test on the GeneXpert Xpress System in a CLIA-Waived (CW) environment was established at three (3) sites using a 3-member panel including one negative sample, one low positive (~1.5x LoD) sample and one moderate positive (~3x LoD) sample. The negative sample consisted of simulated matrix without target microorganism or target RNA. The positive samples were contrived samples in a simulated matrix using inactivated NATtrol SARS-CoV-2 (ZeptoMetrix).
Testing was conducted over five (5) independent, non-consecutive days, using one (1) lot of Xpert Xpress CoV-2 plus cartridges at three (3) participating CW sites each with three (3) untrained/inexperienced operators to yield a total of 90 observations per panel member (3
28
Sites x 3 Operators x 1 Lot x 5 Days x 1 Run x 2 Replicates = 90 observations/panel member).
The percent agreement of the qualitative results for SARS-CoV-2 detection for each panel member analyzed by each of the 9 operators and each site is shown in Table 16. In addition, the overall percent agreement for each sample (% total agreement) and the two-sided Wilson Score confidence intervals (CI) are presented in the last column.
The results from the study are summarized in Table 16.
| | Site 1 | | | | Site 2 | | | | Site 3 | | | | %Total
Agreement and
95% CI by
Panel Member |
|------------------------------|-----------------|-----------------|-----------------|-----------------|-----------------|-----------------|-----------------|-----------------|-----------------|-----------------|-----------------|-----------------|------------------------------------------------------|
| Sample | Op1 | Op2 | Op3 | Site | Op1 | Op2 | Op3 | Site | Op1 | Op2 | Op3 | Site | |
| Negative | 100%
(10/10) | 100%
(10/10) | 100%
(10/10) | 100%
(30/30) | 100%
(10/10) | 100%
(10/10) | 100%
(10/10) | 100%
(30/30) | 100%
(10/10) | 100%
(10/10) | 100%
(10/10) | 100%
(30/30) | 100%
(90/90)
[95.9 % - 100%] |
| SARS-
CoV-2
Low Pos | 100%
(10/10) | 100%
(10/10) | 100%
(10/10) | 100%
(30/30) | 100%
(10/10) | 100%
(10/10) | 100%
(10/10) | 100%
(30/30) | 100%
(10/10) | 100%
(10/10) | 100%
(10/10) | 100%
(30/30) | 100%
(90/90)
[95.9% - 100%] |
| SARS-
CoV-2
Mod
Pos | 100%
(10/10) | 100%
(10/10) | 100%
(10/10) | 100%
(30/30) | 100%
(10/10) | 100%
(10/10) | 100%
(10/10) | 100%
(30/30) | 100%
(10/10) | 100%
(10/10) | 100%
(10/10) | 100%
(30/30) | 100%
(90/90)
[95.9% - 100%] |
Table 14. Summary of the Reproducibility Results - % Agreement
Abbreviation: Op, operator; Pos, positive; Mod, moderate; CI, confidence interval
The evaluation of reproducibility the underlying analyte Ct values for E, N2 and RdRP obtained in the Xpert Xpress CoV-2 plus test was analyzed using nested Analysis of Variance (ANOVA). The mean, standard deviation (SD), and coefficient of variation (CV) between-sites, between-operators, between-lots, between-days, between-runs and within-run for each panel member are presented in Table 17.
29
| Sample | Analyte | Non-
missing
Value | Mean
Ct | Site | | Operator | | Day | | Error | | Total | |
|---------------------------|---------|--------------------------|------------|------|-----|----------|-----|------|-----|-------|-----|-------|-----|
| | | | | SD | CV | SD | CV | SD | CV | SD | CV | SD | CV |
| Negative | SPC | 90 | 28.76 | 0.17 | 0.6 | 0.16 | 0.6 | 0.00 | 0.0 | 0.41 | 1.4 | 0.47 | 1.6 |
| SARS-
CoV-2
Low Pos | E | 90 | 34.43 | 0.00 | 0.0 | 0.27 | 0.8 | 0.17 | 0.5 | 0.55 | 1.6 | 0.63 | 1.8 |
| | N2 | 90 | 38.03 | 0.17 | 0.5 | 0.29 | 0.8 | 0.15 | 0.4 | 0.65 | 1.7 | 0.73 | 1.9 |
| | RdRp | 90 | 37.63 | 0.12 | 0.3 | 0.28 | 0.7 | 0.32 | 0.9 | 0.61 | 1.6 | 0.75 | 2.0 |
| SARS-
CoV-2
Mod Pos | E | 90 | 32.19 | 0.04 | 0.1 | 0.21 | 0.7 | 0.24 | 0.7 | 0.36 | 1.1 | 0.49 | 1.5 |
| | N2 | 90 | 35.84 | 0.12 | 0.3 | 0.23 | 0.7 | 0.15 | 0.4 | 0.45 | 1.3 | 0.55 | 1.5 |
| | RdRp | 90 | 35.48 | 0.12 | 0.4 | 0.26 | 0.7 | 0.18 | 0.5 | 0.42 | 1.2 | 0.54 | 1.5 |
Table 17. Summary of Nested ANOVA by Coefficient of Variation*
*Coefficient of variation = SD/Mean Ct * 100%
1.4.2 Clinical Performance
The clinical performance of the Xpert Xpress CoV-2 plus test was evaluated in a multi-site, observational and method comparison study that included 22 geographically diverse CLIAwaived sites in the United States (US) using specimens collected from individuals showing signs and symptoms of respiratory infection. Of the 22 sites, 21 performed Xpert testing and specimen collection, and 1 site performed comparator and discrepant testing.
Specimens tested included prospective clinical NPS and NS specimens collected in UTM/VTM. Available demographic data from the individuals from whom the specimens were collected are presented in Table 18.
| Prospectively Collected Fresh
Specimens from 2022 | NPS
(N=961) | NS
(N=973) | Overall
(N=1934) |
|------------------------------------------------------|----------------|---------------|---------------------|
| Gender | | | |
| Female | 569 (59.2%) | 616 (63.3%) | 1185 (61.3%) |
| Male | 392 (40.8%) | 357 (36.7%) | 749 (38.7%) |
| Age Group (Years) | | | |
| ≤5 | 8 (0.8%) | 54 (5.5%) | 62 (3.2%) |
| 6-21 | 275 (28.6%) | 285 (29.3%) | 560 (29.0%) |
| 22-59 | 537 (55.9%) | 505 (51.9%) | 1042 (53.9%) |
| ≥60 | 141 (14.7%) | 129 (13.3%) | 270 (14.0%) |
| Race | | | |
Table 18. Demographic Summary | |
---|---|
------------------------------- | -- |
30
| Prospectively Collected Fresh
Specimens from 2022 | NPS
(N=961) | NS
(N=973) | Overall
(N=1934) |
|------------------------------------------------------|----------------|---------------|---------------------|
| American Indian or Alaska Native | 0 (0%) | 1 (0.1%) | 1 (0.1%) |
| Asian | 27 (2.8%) | 25 (2.6%) | 52 (2.7%) |
| Black or African American | 225 (23.4%) | 217 (22.3%) | 442 (22.9%) |
| White | 656 (68.3%) | 661 (67.9%) | 1317 (68.1%) |
| Black or African American, White | 4 (0.4%) | 4 (0.4%) | 8 (0.4%) |
| Other Mixed (each N≤5) | 3 (0.3%) | 2 (0.2%) | 5 (0.3%) |
| Participant Declined to Answer or
Unknown | 46 (4.8%) | 63 (6.5%) | 109 (5.6%) |
| Ethnicity | | | |
| Hispanic | 75 (7.8%) | 81 (8.3%) | 156 (8.1%) |
| Non-Hispanic | 861 (89.6%) | 857 (88.1%) | 1718 (88.8%) |
| Participant Declined to Answer or
Unknown | 25 (2.6%) | 35 (3.6%) | 60 (3.1%) |
| COVID-19 Vaccination Status | | | |
| Vaccinated | 721 (75.0%) | 717 (73.7%) | 1438 (74.4%) |
| Not Vaccinated | 222 (23.1%) | 239 (24.6%) | 461 (23.8%) |
| Unknown | 18 (1.9%) | 17 (1.7%) | 35 (1.8%) |
Positive Percent Agreement (PPA) and Negative Percent Agreement (NPA) were determined when specimens were tested using Xpert Xpress CoV-2 plus side-by-side with a U.S. FDAcleared molecular respiratory panel that included SARS-CoV-2 in a randomized and blinded fashion. Discrepant results between Xpert Xpress CoV-2 plus and the comparator were investigated using a U.S FDA EUA SARS-CoV-2 molecular test. Additionally, nondeterminate rate was determined for Xpert Xpress CoV-2 plus. Based on the specimens that yielded non-determinate results with Xpert Xpress CoV-2 plus, the non-determinate rate was 0.7% (7/961) with NPS and 0.4% (4/973) with NS specimens.
A total of 1783 specimens, including 883 NPS and 900 NS specimens that yielded valid results by both the Xpert Xpress CoV-2 plus and the U.S. FDA-cleared molecular respiratory panel were included in the clinical performance evaluation. The Xpert Xpress CoV-2 plus demonstrated a PPA and NPA of 98.2% and 99.1%, respectively in NPS specimens and 99.0% and 99.1%, respectively in NS specimens (Table 19).
31
Comparator | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Overall | NPS | NS | ||||||||
Positive | Negative | Total | Positive | Negative | Total | Positive | Negative | Total | ||
Xpert | ||||||||||
Xpress | ||||||||||
CoV-2 plus | Positive | 215 | 14 | 229 | 112 | 7b | 119 | 103 | 7d | 110 |
Negative | 3 | 1551 | 1554 | 2a | 762 | 764 | 1c | 789 | 790 | |
Total | 218 | 1565 | 1783 | 114 | 769 | 883 | 104 | 796 | 900 | |
PPA | ||||||||||
(95% CI) | 98.6% | |||||||||
(96.0% - 99.5%) | 98.2% | |||||||||
(93.8% - 99.5%) | 99.0% | |||||||||
(94.8% - 99.8%) | ||||||||||
NPA | ||||||||||
(95% CI) | 99.1% | |||||||||
(98.5% - 99.5%) | 99.1% | |||||||||
(98.1% - 99.6%) | 99.1% | |||||||||
(98.2% - 99.6%) | ||||||||||
NPS: nasopharyngeal swab; NS: anterior nasal swab; PPA: Positive Percent Agreement; NPA: Negative Percent | ||||||||||
Agreement; CI: Confidence Interval | ||||||||||
a. Discrepant test results based on a U.S. FDA EUA SARS-CoV-2 molecular test: 1/2 SARS-CoV-2 positive; 1/2 SARS-CoV-2 | ||||||||||
negative | ||||||||||
b. Discrepant test results based on a U.S. FDA EUA SARS-CoV-2 molecular test: 7/7 SARS-CoV-2 negative |
Table 19. Xpert Xpress CoV-2 plus Performance Results
b. Discrepant test results based on a U.S. FDA EUA SARS-COV-2 molecular test: /// SARS-COV-2 negative
c. Discrepant test results based on a U.S. FDA SARS-CoV-2 molecular test: 1/1 SARS-CoV-2 negative
Discrepant test results based on a U.S. FDA SARS-CoV-2 molecular test: 1/1 SARS-CoV-2 negative d.
Discrepant test results based on a U.S. FDA SARS-CoV-2 positive; 5/7 SARS-CoV-2 positive; 5/7 SARS-CoV-2 negative; 1/7 invalid results
1.5 Conclusions
The results of the analytical and clinical performance studies summarized above demonstrate that the Xpert Xpress CoV-2 plus test is substantially equivalent to the predicate device.