← Product Code [NQX](/submissions/MI/subpart-b%E2%80%94diagnostic-devices/NQX) · K243625 # Xpert MRSA/SA SSTI (K243625) _Cepheid® · NQX · Dec 18, 2024 · Microbiology · SESE_ **Canonical URL:** https://fda.innolitics.com/submissions/MI/subpart-b%E2%80%94diagnostic-devices/NQX/K243625 ## Device Facts - **Applicant:** Cepheid® - **Product Code:** [NQX](/submissions/MI/subpart-b%E2%80%94diagnostic-devices/NQX.md) - **Decision Date:** Dec 18, 2024 - **Decision:** SESE - **Submission Type:** Special - **Regulation:** 21 CFR 866.1640 - **Device Class:** Class 2 - **Review Panel:** Microbiology ## Indications for Use The Xpert® MRSA/SA Skin and Soft Tissue Infection test (Xpert MRSA/SA SSTI test) performed on the GeneXpert® Instrument Systems is a qualitative in vitro diagnostic test intended for the detection of Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA) from skin and soft tissue infection swabs. The test utilizes automated real-time polymerase chain reaction (PCR) to detect MRSA/SA DNA. The Xpert MRSA/SA SSTI test is indicated for use in conjunction with other laboratory tests, such as microbiology culture, and clinical data available to the clinician as an aid in the detection of MRSA/SA from skin and soft tissue infections. The Xpert MRSA/SA SSTI test is not intended to monitor treatment for MRSA/SA infections. Concomitant cultures for SA and MRSA are necessary to recover organisms for susceptibility testing or epidemiological typing. In a mixed culture containing MRSA/SA and other organisms (e.g., Gram-negative bacilli, yeast), results can be false negative or variable depending on the concentration of MRSA/SA present, particularly if the concentration of MRSA/SA is close to the limit of detection (LoD) of the test. ## Device Story The Xpert MRSA/SA SSTI is a molecular diagnostic test for detecting MRSA and SA DNA in skin and soft tissue infection samples. The device utilizes the GeneXpert Instrument Systems, including the GeneXpert Infinity Systems, to process samples. The system performs automated nucleic acid extraction and real-time PCR amplification and detection. The test is used in clinical laboratory settings by trained personnel. Results are provided to healthcare providers to assist in the management and control of MRSA/SA infections. This submission covers modifications to include the GeneXpert Infinity Systems in the instrument family and updates to labeling and assay definition files. ## Clinical Evidence No clinical data provided; substantial equivalence is supported by design control activities, risk analysis, and verification/validation of the modified instrument compatibility. ## Technological Characteristics The device utilizes real-time PCR technology for nucleic acid detection. It is designed for use with the GeneXpert Instrument Systems, including the GeneXpert Infinity Systems. The system is a multiplex test system for clinical chemistry and microbiology applications. It uses assay definition files for instrument configuration. ## Regulatory Identification An antimicrobial susceptibility test powder is a device that consists of an antimicrobial drug powder packaged in vials in specified amounts and intended for use in clinical laboratories for determining in vitro susceptibility of bacterial pathogens to these therapeutic agents. Test results are used to determine the antimicrobial agent of choice in the treatment of bacterial diseases. ## Predicate Devices - Xpert MRSA/SA SSTI ([K080837](/device/K080837.md)) ## Submission Summary (Full Text) > This content was OCRed from public FDA records by [Innolitics](https://innolitics.com). If you use, quote, summarize, crawl, or train on this content, cite Innolitics at https://innolitics.com. > > Innolitics is a medical-device software consultancy. We help companies design, build, and clear FDA-regulated software and AI/ML devices, including [a 510(k)](https://innolitics.com/services/510ks/), [a De Novo](https://innolitics.com/services/regulatory/), [a SaMD](https://innolitics.com/services/end-to-end-samd/), [an AI/ML medical device](https://innolitics.com/services/medical-imaging-ai-development/), or [an FDA regulatory strategy](https://innolitics.com/services/regulatory/). {0} FDA U.S. FOOD & DRUG ADMINISTRATION # SPECIAL 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY ## I Background Information: A 510(k) Number K243625 B Applicant Cepheid C Proprietary and Established Names Xpert MRSA/SA SSTI D Regulatory Information | Product Code(s) | Classification | Regulation Section | Panel | | --- | --- | --- | --- | | NQX | Class II | 21 CFR 866.1640 Antimicrobial Susceptibility Test Powder | MI – Microbiology | | OOI | Class II | 21 CFR 862.2570 Instrumentation for clinical multiplex test systems | CH – Clinical Chemistry | ## II Review Summary: This 510(k) submission contains information/data on modifications made to the submitter’s (i.e., Cepheid’s) own CLASS II device requiring a 510(k). The following items are present and acceptable. 1. The name and 510(k) number of the SUBMITTER’S previously cleared device. 2. Submitter’s statement that the INTENDED USE/INDICATIONS FOR USE of the modified device as described in its labeling HAS CHANGED along with the proposed labeling which includes instructions for use and package inserts. These labeling changes are considered minor and do not affect the intended use of the original or modified device. The changes in the Intended Use/Indications for Use statement of the modified device (K243625) aim to: (a) Incorporate by name the “GeneXpert Instrument Systems” family of instruments—in order to accommodate a new member (the GeneXpert Infinity Systems) of this family whose other members represent instruments that were previously cleared with the predicate (K080837). (b) Modify the device name from the previous “Cepheid Xpert MRSA/SA SSTI Assay” to “Xpert MRSA/SA SSTI” in the Intended Use/Indications for Use statement. Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993-0002 www.fda.gov {1} (c) Describe the modified device as a “test” (which incorporates assay and instrument) instead of as an “assay” as was previously done. (d) Apply minor clarifying changes to the text of the Intended Use/Indications for Use statement. The changes in the labeling of the modified device (K243625) aim to provide the End User/Customer with a set of updated operational documents, i.e., operator manual for the newly added GeneXpert Infinity System instruments, updated user instructions for performing the Xpert MRSA/SA SSTI test on new and existing instruments, and an updated assay definition file containing assay specifics to be imported to the newly added instruments. 3. A description of the device MODIFICATION(S), including clearly labeled diagrams, photographs, and user’s manuals in sufficient detail to demonstrate that the FUNDAMENTAL SCIENTIFIC TECHNOLOGY of the modified device has not changed. 4. Comparison Information (i.e., similarities and differences) to the submitter’s legally marketed predicate device including, labeling, intended use, and physical characteristics. 5. A Design Control Activities Summary which includes: (a) Identification of Risk Analysis method(s) used to assess the impact of the modification on the device and its components, and the results of the analysis. (b) Based on the Risk Analysis, an identification of the verification and/or validation activities required, including methods or tests used and acceptance criteria to be applied. The labeling for this modified subject device has been reviewed to verify that the indication/intended use for the device is unaffected by the modification. In addition, the submitter’s description of the particular modification(s) and the comparative information between the modified and unmodified devices demonstrate that the fundamental scientific technology has not changed. The submitter has provided the design control information as specified in The New 510(k) Paradigm and on this basis, I recommend the device be determined substantially equivalent to the previously cleared device. K243625 - Page 2 of 2 --- **Source:** [https://fda.innolitics.com/submissions/MI/subpart-b%E2%80%94diagnostic-devices/NQX/K243625](https://fda.innolitics.com/submissions/MI/subpart-b%E2%80%94diagnostic-devices/NQX/K243625) **Published by [Innolitics](https://innolitics.com)** — a medical-device software consultancy. We help companies design, build, and clear FDA-regulated software and AI/ML devices. If you're preparing [a 510(k)](https://innolitics.com/services/510ks/), [a De Novo](https://innolitics.com/services/regulatory/), [a SaMD](https://innolitics.com/services/end-to-end-samd/), [an AI/ML medical device](https://innolitics.com/services/medical-imaging-ai-development/), or [an FDA regulatory strategy](https://innolitics.com/services/regulatory/), [get in touch](https://innolitics.com/contact). **Cite:** Innolitics at https://innolitics.com