(27 days)
The BD ProbeTec™ ET Chlamydia trachomatis and Neisseria gonorrohoeae Amplified DNA Assays, when tested with the BD ProbeTec ET System, uses Strand Displacement Amplification (SDA) technology for the direct, qualitative detection of Chlamydia trachomatis and Neisseria gonorrhoeae DNA in endocervical swabs, male urethral swabs, and in female and male urine specimens as evidence of infection with C. trachomatis and N. gonorroheae, or of co-infection with both C. trachomatis and N. gonorroheae. Specimens may be from symptomatic and asymptomatic females and males. A separate Amplification Control is an option for inhibition testing (BD ProbeTec ET CT/GC/AC Reagent Pack). The BD ProbeTec ET CT/GC assays may be performed using either the BD ProbeTec ET System or a combination of the BD ProbeTec ET System and the BD Viper™ instrument.
The BD ProbeTec™ Urine Preservative Transport Kit with NAP Guard™ technology is designed to preserve and transport Chlamydia trachomatis and Neisseria gonorrhoeae in male and female urine specimens from symptomatic and asymptomatic individuals prior to processing for analysis with the BD ProbeTec ET Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) Amplified DNA Assays.
The BD ProbeTec ET CT/GC amplified DNA assays utilize homogeneous SDA technology as the amplification method and fluorescent energy transfer (ET) as the detection method to test for the presence of CT and GC in clinical specimens.
The BD ProbeTec Urine Preservative Transport Kit with NAP Guard technology allows for an extended range of time and temperature conditions for storage and transport when testing for the presence of Chlamydia trachomatis and Neisseria gonorrhoeae in urine specimens using the BD ProbeTec ET CT and GC Amplified DNA Assays. Each UPT contains 50 µL of NAP Guard (2 M Guanidine Thiocyanate, 742.5 mM K2EDTA) packaged with a disposable transfer pipette. Urine is transferred to the UPT tube, mixed with the tube contents and transported to the test site for processing according to the assay package insert.
Below is a summary of the acceptance criteria and the study proving the device meets these criteria, based on the provided text:
Acceptance Criteria and Device Performance
This 510(k) submission is for modifications to the BD ProbeTec Urine Processing Pouch (UPP) and the addition of neat urine as a sample type. The key modifications assessed were: Materials Modification (affecting Specimen Stability), Input Specimen Volume Requirement (affecting Sensitivity), and Processing/Workflow Modification (affecting Assay Interference). The original BD ProbeTec ET CT/GC Amplified DNA Assays are the predicate device, and the modifications do not change the intended use of the assays.
The study compares the performance of the new BD ProbeTec™ Urine Preservative Transport (UPT) and neat urine sample types against the predicate UPP device.
| Parameter | Acceptance Criteria (Implied by Comparison to Predicate) | Reported Device Performance (UPT and Neat Urine) |
|---|---|---|
| Analytical Limit of Detection | Equivalent to or better than predicate UPP. | UPT and Neat urine sample types have analytical limits of detection equivalent to or better than UPP. |
| Interfering Substances | No significant impact on positive and negative assay results compared to predicate UPP. | Potential interferents have no significant impact to positive and negative assay results with UPT and Neat urine sample types. |
| Specimen Stability | UPT to exceed UPP stability; Neat urine stability to be established. | UPT specimen stability exceeds UPP specimen stability. Neat urine specimen stability is established. |
| Clinical Performance | Equivalent to predicate UPP. | UPT and Neat urine performance characteristics are equivalent to UPP. |
Study Details
The provided text describes comparison studies conducted to establish substantial equivalence for the modifications.
2. Sample Size and Data Provenance
The document does not explicitly state the sample sizes used for the test sets (comparison studies) for each parameter (Analytical Limit of Detection, Interfering Substances, Specimen Stability, Clinical Performance).
The data provenance is not explicitly stated (e.g., country of origin). The studies appear to be retrospective as they are comparisons to an already cleared predicate device (UPP) and involve evaluating different sample collection and processing methods, rather than following patients prospectively.
3. Number of Experts and Qualifications for Ground Truth of Test Set
The document does not mention the use of experts to establish ground truth for the test set. Given the nature of the device (in vitro diagnostic assay), the ground truth for performance characteristics like LoD, interference, and clinical performance would typically be established by laboratory reference methods or clinical diagnosis, not expert consensus on image interpretation.
4. Adjudication Method for the Test Set
The document does not describe any adjudication method. This is not typically applicable for laboratory-based in vitro diagnostic performance studies.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This type of study is relevant for imaging devices or decision-support systems where human readers interpret data, and is not applicable to this in vitro diagnostic assay.
6. Standalone (Algorithm Only) Performance
Yes, the studies described are essentially standalone in terms of the analytical performance of the assay itself with the modified sample types. The tests evaluate the assay's ability to detect Chlamydia trachomatis and Neisseria gonorrhoeae DNA in urine samples collected and stored using the UPT or as neat urine, independently of human interpretation of the assay results. The "human-in-the-loop" aspect is largely limited to sample collection and laboratory processing, not interpretation of the assay's output.
7. Type of Ground Truth Used
The ground truth used for such in vitro diagnostic assays typically involves:
- Analytical LoD: Known concentrations of target analytes (e.g., bacterial DNA) prepared in a laboratory setting.
- Interfering Substances: Testing with known interfering substances added to samples that are negative or contain known concentrations of analytes.
- Specimen Stability: Testing samples with known analyte concentrations over time under specified storage conditions.
- Clinical Performance: Comparison against a gold standard (e.g., culture, another FDA-cleared molecular test considered highly accurate, or a composite reference method) using clinical specimens from symptomatic and asymptomatic individuals. While not explicitly stated as "clinical performance" ground truth, it's implied that the "clinical performance characteristics are equivalent" to the UPP, which would have established its own clinical ground truth.
8. Sample Size for the Training Set
The document does not provide information about a "training set" for the assay. This device is an in vitro diagnostic assay, not an AI/ML-based algorithm that typically requires a discrete training set. Therefore, the concept of a "training set" as understood in AI/ML is not directly applicable here. The assay's parameters would have been established and optimized during its development phase through internal validation studies, not a "training set" in the typical AI/ML sense.
9. How the Ground Truth for the Training Set was Established
As mentioned above, the concept of a "training set" does not directly apply to this in vitro diagnostic assay in the way it does for AI/ML models. For the initial development and optimization of the assay (which could be considered analogous to "training" in a broad sense), ground truth would have been established through a combination of:
- Spiked samples: Samples (e.g., urine) spiked with known quantities of C. trachomatis and N. gonorrhoeae DNA or whole organisms.
- Characterized clinical samples: Samples from patients with confirmed infections (e.g., by culture or established PCR methods) and uninfected individuals.
These would be used to optimize assay parameters such as primer design, reaction conditions, and detection thresholds, rather than to "train" an algorithm.
§ 866.3390
Neisseria spp. direct serological test reagents.(a)
Identification. Neisseria spp. direct serological test reagents are devices that consist of antigens and antisera used in serological tests to identifyNeisseria spp. from cultured isolates. Additionally, some of these reagents consist ofNeisseria spp. antisera conjugated with a fluorescent dye (immunofluorescent reagents) which may be used to detect the presence ofNeisseria spp. directly from clinical specimens. The identification aids in the diagnosis of disease caused by bacteria belonging to the genusNeisseria, such as epidemic cerebrospinal meningitis, meningococcal disease, and gonorrhea, and also provides epidemiological information on diseases caused by these microorganisms. The device does not include products for the detection of gonorrhea in humans by indirect methods, such as detection of antibodies or of oxidase produced by gonococcal organisms.(b)
Classification. Class II (performance standards).