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The Xpert® FII & FV test is a qualitative in vitro diagnostic genotyping test for the detection of Factor V alleles from sodium citrate or EDTA anticoagulated whole blood. The test is performed on the GeneXpert® Instrument Systems. This test is intended to provide results for Factor II (G20210A) and Factor V Leiden (G1691A) mutations as an aid in the diagnosis in individuals with suspected thrombophilia.

Xpert FII & FV is an automated genotyping test for detecting Factor II and Factor V normal and mutant alleles directly from sodium citrate or EDTA anticoagulated whole blood specimens. Blood specimens are drawn into either sodium citrate or EDTA anticoagulant tubes. Following brief mixing of the sample. 50 uL of the blood sample is transferred to the bottom wall of the Sample opening of the Xpert FII & FV test cartridge. The user initiates a test from the system user interface and places the cartridge into the GeneXpert Instrument System.

The Xpert FII & FV test includes reagents for the detection of Factor II and Factor V normal and mutant alleles. The primers and probes in the Xpert FII & FV test determine the genotype of the Factor II gene (at position 20210) and/or the Factor V gene (at position 1691). The test includes a Sample Processing Control (SPC) to confirm adequate processing and to monitor the presence of inhibitor(s) in the PCR assay. The Probe Check Control (PCC) verifies reagent rehydration, PCR tube filling in the cartridge, probe integrity, and dye stability.

The GeneXpert Instrument Systems family is comprised of GeneXpert Dx System, GeneXpert Infinity System, and GeneXpert System with Touchscreen. The GeneXpert Instrument Systems automate and integrate sample processing, nucleic acid amplification and detection of the target sequences in simple or complex samples using real-time polymerase chain reaction (PCR). The systems consist of an instrument, computer or touchscreen, and preloaded software for running the tests and viewing the results. The GeneXpert Instrument Systems require the use of singleuse disposable cartridges that hold the PCR reagents and host the PCR process. Because the cartridges are self-contained, cross-contamination between samples is minimized.

The GeneXpert Instrument Systems have 1 to 80 modules (depending upon the instrument) that are each capable of performing separate sample preparation and real-time PCR tests. Each module contains a syringe drive for dispensing fluids (i.e., the syringe drive activates the plunger that works in concert with the rotary valve in the cartridge to move fluids between chambers), an ultrasonic horn for lysing cells or spores, and a proprietary I-CORE® thermocycler for performing real-time PCR and detection.

The Xpert FII & FV test performed on the GeneXpert Instrument Systems provides results in approximately 30 minutes.

This document is a 510(k) summary for the Xpert FII & FV diagnostic test, seeking to remove a limitation statement and make minor branding/catalog number changes. It does not contain a study explicitly detailing acceptance criteria and performance against those criteria for the current submission. Instead, it refers to prior clearance (K082118) for the clinical validation supporting the removal of the limitation statement, and asserts that the current changes do not impact performance.

Therefore, the following information is extracted or inferred based on the provided document:

1. Table of Acceptance Criteria and Reported Device Performance:

The document explicitly states: "No new performance data were provided in this submission." The basis for substantial equivalence relies on the device being identical to its predicate (K223046) in all technological characteristics relevant to performance. The one significant change (removal of the pediatric patient limitation) is supported by prior clinical validation data (K082118). Since no new performance data or acceptance criteria are presented for this specific submission, this table cannot be fully completed from the provided text.

However, based on the nature of a genetic mutation detection system, typical acceptance criteria would involve analytical sensitivity, analytical specificity, and clinical performance (e.g., concordance with a gold standard). Without the original K082118 submission, specific numerical criteria are not available.

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

• Sample Size: Not explicitly stated in this document. The document refers to "clinical validation data that was submitted and reviewed as part of the original device clearance (K082118)" as the basis for removing the pediatric limitation. The sample size for that original study is not provided here.
• Data Provenance: Not explicitly stated in this document. Given it's a 510(k) for a US market device, it is likely the original clinical validation (K082118) included US data, but this is not confirmed. It refers to "clinical validation data," which typically implies prospective collection of patient samples.

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

• Not explicitly stated in this document. This level of detail would typically be found in the original clinical validation report (K082118). For genotyping, ground truth is usually established by orthogonal molecular methods, not primarily by expert consensus in the same way as imaging or pathology interpretation.

4. Adjudication Method for the Test Set:

• Not applicable/Not mentioned. For genetic tests where the ground truth is often established through well-defined molecular techniques (e.g., Sanger sequencing or a validated reference method), adjudication by multiple experts in the traditional sense (like for imaging reads) is generally not performed. The ground truth is objective.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done:

• No, an MRMC comparative effectiveness study was not done. This type of study is relevant for interpretive tasks (e.g., radiologists reading images) where human performance is being evaluated and compared with and without AI assistance. The Xpert FII & FV is an automated genotyping test; it does not involve human readers interpreting results in the same manner.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done:

• Yes, the performance characteristics mentioned (e.g., analytical sensitivity, specificity) for a molecular diagnostic test like the Xpert FII & FV are inherently "standalone" in nature. The device itself performs the assay and provides a qualitative genotype call. The results are automated and interpreted by the diagnostic software.

7. The Type of Ground Truth Used:

• Not explicitly stated in this document, but for genetic tests, the ground truth is typically established by orthogonal molecular methods, such as Sanger sequencing or another highly accurate, validated reference genotyping method. It is not based on expert consensus, pathology, or outcomes data in the way these terms are typically used for imaging or disease diagnosis.

8. The Sample Size for the Training Set:

• Not explicitly stated in this document. The device uses real-time PCR for detection, and while there might be algorithm tuning within the software, the foundational "training" often refers to the design and optimization of primers and probes, and establishment of cut-offs, rather than machine learning on a large training set of clinical samples. The document refers to "clinical validation data" for performance, but not specifically to a training set size for an algorithm.

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

• Not explicitly stated in this document. This would be part of the original developmental studies for the device (predating K082118). For a PCR-based test, ground truth for developing and optimizing the assay would involve samples with known genotypes confirmed through reference methods.

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The Xpert® FII & FV test is a qualitative in vitro diagnostic genotyping test for the detection of Factor II and Factor V alleles from sodium citrate or EDTA anticoagulated whole blood. The test is performed on the Cepheid GeneXpert® Instrument Systems. This test is intended to provide results for Factor II (G20210A) and Factor V Leiden (G1691A) mutations as an aid in the diagnosis in individuals with suspected thrombophilia.

The Cepheid Xpert® FII & FV is a rapid, automated DNA test for detecting FII and FV normal and mutant alleles directly from sodium citrate or EDTA anticoagulated whole blood specimens. Blood specimens are drawn into either sodium citrate or EDTA anticoagulant tubes. Following brief mixing of the sample, 50 uL of the blood sample is transferred to the bottom wall of the Sample opening of the Xpert FII & FV test cartridge. The user initiates a test from the system user interface and places the cartridge into the GeneXpert® Instrument system instrument platform (comprised of the GeneXpert Dx Systems and GeneXpert Infinity Systems), which performs hands-off real-time, multiplex polymerase chain reaction (PCR) for detection of DNA. In the GeneXpert Instrument Systems platform, sample preparation, amplification, and real-time detection are all fully-automated and completely integrated.

The GeneXpert Instrument Systems have 1 to 80 randomly accessible modules, depending upon the instrument, that are each capable of performing separate sample preparation and real- time PCR tests. Each module contains a syringe drive for dispensing fluids (i.e., the syringe drive activates the plunger that works in concert with the rotary valve in the cartridge to move fluids between chambers), an ultrasonic horn for lysing cells or spores, and a proprietary I-CORE® thermocycler for performing real-time PCR and detection.

The Xpert FII & FV test includes reagents for the detection of Factor II and Factor V normal and mutant alleles. The primers and probes in the Xpert FII & FV test determine the genotype of the Factor II gene (at position 20210) and the Factor V gene (at position 1691). The test includes a Sample Processing Control to confirm adequate processing of the target bacteria and to monitor the presence of inhibitor(s) in the PCR assay. The Probe Check Control (PCC) verifies reagent rehydration, PCR tube filling in the cartridge, probe integrity, and dye stability.

The test is performed on the Cepheid GeneXpert Instrument Systems, which automate and integrate sample purification, nucleic acid amplification of the target sequences in simple or complex samples using real-time PCR. The systems consist of an instrument, personal computer, and preloaded software for running the tests and viewing the results. The GeneXpert Instrument Systems require the use of single-use disposable cartridges that hold the PCR reagents and host the PCR process. Because the cartridges are self-contained, crosscontamination between samples is minimized. In this platform, additional sample preparation, amplification, and real-time detection are all fully- automated and completely integrated. The Xpert FII & FV test performed on the GeneXpert Instrument Systems provides results in approximately 30 minutes.

The FDA 510(k) summary for the Cepheid Xpert® FII & FV device outlines its performance and validation, primarily focusing on demonstrating substantial equivalence to a predicate device when used with new instrument systems (GeneXpert Infinity Systems).

Here's an analysis of the provided information against your requested criteria:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not provide a formal table of quantitative acceptance criteria with corresponding performance metrics like sensitivity, specificity, accuracy, etc. This is typical for a Special 510(k) submission where the primary objective is to demonstrate that a change (new instrument compatibility) does not negatively impact the existing, previously cleared performance.

Instead, the "Performance Data" section states:

• Acceptance Criteria (Implicit): That the performance claims of the Xpert FII & FV test were not impacted by the use of the GeneXpert Infinity Systems.
• Reported Device Performance: This was assessed through verification studies, including a "Cartridge Hold Time study" and a "Functional Testing study." The document explicitly states that the results "determined that the performance claims of the Xpert FII & FV test were not impacted."

Therefore, the performance is essentially stated as "comparable to the predicate device and original claims," rather than providing new specific rates (e.g., "99% sensitivity," "98% specificity").

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

The document does not explicitly state the sample sizes for the "Cartridge Hold Time study" and "Functional Testing study." It only mentions that these were "verification studies."

• Data Provenance: Not specified in terms of country of origin.
• Retrospective or Prospective: Not explicitly stated, but typically, verification studies like these for in vitro diagnostic devices would involve prospective testing of samples under controlled conditions to assess functionality and stability on the new instrument.

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

This type of information is not applicable to this device and study. The Xpert® FII & FV test is a qualitative in vitro diagnostic genotyping test for detecting specific DNA mutations (Factor II and Factor V alleles). The "ground truth" for such a device is established by the known genetic status of the samples used in the studies (e.g., confirmed Factor II or Factor V mutation presence/absence via reference methods or defined synthetic constructs), not by expert human interpretation of images or other subjective data. No human experts are used to establish ground truth for this kind of molecular diagnostic test performance.

4. Adjudication Method for the Test Set

Not applicable. As explained above, the "ground truth" for a genotyping test is based on direct molecular confirmation, not on subjective interpretations requiring adjudication.

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

Not applicable. The Xpert® FII & FV is an automated diagnostic test that provides a definitive genetic result. It does not involve human readers interpreting output that would be improved with AI assistance, nor is it a diagnostic imaging device where MRMC studies are common.

6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study

This is the primary mode of operation for this device. The Xpert® FII & FV test is an automated system as described: "perform[s] hands-off real-time, multiplex polymerase chain reaction (PCR) for detection of DNA." The results ("Result," "Not Detected," or "Invalid") are generated by the instrument's internal algorithms based on PCR amplification signals. The human interaction is limited to sample loading and initiating the test. Therefore, the "Functional Testing study" and "Cartridge Hold Time study" effectively assess the standalone performance of the algorithm and instrument system.

7. The Type of Ground Truth Used

The ground truth for a genotyping test is based on the presence or absence of specific DNA sequences/mutations. While not explicitly stated how this truth was established for the specific "verification studies," for molecular diagnostic tests, ground truth is typically confirmed using:

• Reference molecular methods: Such as Sanger sequencing or highly validated in-house PCR assays.
• Characterized samples: Samples with known genetic status (e.g., from biobanks, synthetic constructs, or previously validated patient samples).
• Clinical diagnosis/outcomes data: In some cases, to correlate the genetic findings with the clinical presentation, although for genotyping tests, the primary ground truth is molecular.

Given the nature of this device, it would be based on the confirmed genetic status of the samples.

8. The Sample Size for the Training Set

This information is not provided. As this is a Special 510(k) for an instrument change, the focus is on verification rather than a full re-validation involving new training sets. The underlying algorithms and core test technology (primers, probes, PCR) remain the same as the predicate device. Training sets would have been used in the original development and validation of the Xpert® FII & FV test (K082118).

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

Not provided in this document as it pertains to the original development of the predicate device (K082118), not this Special 510(k). For the original development, ground truth would have been established as described in point 7 (reference molecular methods, characterized samples).

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