(263 days)
Oragene-Dx is intended for use in the non-invasive collection of saliva samples. DNA from the saliva sample is isolated, stabilized, and suitable for use in FDA cleared molecular diagnostic applications. Saliva may be collected by spitting directly into the Oragene-Dx container or may be transferred into the Oragene·Dx container using a sponge. Saliva samples collected using Oragene·Dx are stabilized and can be transported and/or stored long term at ambient conditions.
The Oragene·Dx family of products offers reliable collection, transportation and long-term room temperature storage of human DNA from saliva. Oragene Dx is a non-invasive alternative for collecting high quality and quantity DNA for use in molecular diagnostic applications. All formats consist of a collection tube, stabilizing liquid and optional sponges for assisted collection. After saliva is collected, the stabilizing liquid is mixed with the sample. Saliva can be delivered directly by spitting or using provided sponges to transfer saliva into the device.
Here's a breakdown of the acceptance criteria and study information for the Oragene·Dx device, based on the provided text:
1. Acceptance Criteria and Reported Device Performance
The acceptance criteria for the Oragene·Dx device are not explicitly stated as distinct pass/fail thresholds in the provided document. However, the performance characteristics and the successful outcome of the studies (e.g., 100% correct calls after re-testing in most cases) imply that these reported values met the internal and FDA requirements for substantial equivalence. The key performance metrics evaluated were:
- DNA Yield (µg): Quantity of DNA extracted.
- DNA Concentration (ng/µL): Concentration of DNA in the extracted sample.
- A260/A280 Ratio: Indicator of DNA purity (ratio of absorbance at 260 nm to 280 nm). A value around 1.7 to 2.0 typically indicates pure DNA.
- % Correct Calls on downstream molecular diagnostic application: The ability of the extracted DNA to produce accurate results in the eSensor® Warfarin Sensitivity Saliva Test.
- Stability: Ability to maintain DNA quality and quantity over time and under various storage/transport conditions.
- Tolerance to interfering substances: Ability to perform correctly despite the presence of common interfering substances.
| Performance Metric | Acceptance Criteria (Implied) | Reported Device Performance (Summary) |
|---|---|---|
| DNA Yield (µg) | Adequate for FDA cleared molecular diagnostic applications. | OGD-500: Mean 58.52 ± 47.02 µg; Median 48.44 µg; 95% samples ≥ 13.1 µg. |
| OGD-575: Mean 13.50 ± 8.84 µg; Median 10.96 µg; 95% samples ≥ 3.8 µg. | ||
| OXD-525: Mean 50.10 ± 42.38 µg; Median 33.35 µg; 95% samples ≥ 14.8 µg. | ||
| OYD-500: Mean 56.05 ± 46.84 µg; Median 37.28 µg; 95% samples ≥ 13.0 µg. | ||
| DNA Concentration (ng/µL) | Adequate for FDA cleared molecular diagnostic applications. | OGD-500: Mean 68.11 ± 55.27 ng/µL; Median 55.27 ng/µL; 95% samples ≥ 16.0 ng/µL. |
| OGD-575: Mean 41.12 ± 24.59 ng/µL; Median 33.20 ng/µL; 95% samples ≥ 11.2 ng/µL. | ||
| OXD-525: Mean 88.89 ± 74.51 ng/µL; Median 60.22 ng/µL; 95% samples ≥ 27.6 ng/µL. | ||
| OYD-500: Mean 65.38 ± 55.94 ng/µL; Median 42.11 ng/µL; 95% samples ≥ 14.8 ng/µL. | ||
| A260/A280 Ratio | Indicative of pure DNA (e.g., 1.7-2.0 or appropriate range). | All formats: Mean 1.7 ± 0.1; Median 1.7. |
| OGD-500: 98% samples 1.5 - 2.0. | ||
| Other formats: 98% samples 1.5 - 1.9. | ||
| % Correct Calls (eSensor Test) | 100% correct calls (post re-testing where applicable). | Initial Performance (Table 27): Ranged from 93.0% to 100% (with "no-calls"). |
| After Re-test (Table 27, Volume Tolerance, Reproducibility): Consistently 100% correct calls after re-testing or investigation, demonstrating suitability for the downstream application. | ||
| Sample Volume Tolerance | Maintenance of DNA quality and performance across volume range. | Maintained A260/A280 ratio and performance on eSensor test. 100% correct calls after re-testing for volumes from 0.58 mL to 3.64 mL. |
| Shelf-Life Stability | 24 months at room temperature (-20°C to 50°C transport). | Supported. Devices passed physical/chemical evaluations. |
| Post-Collection Sample Stability | 12 months at room temperature (-20°C to room temp), 3 months at 50°C | Supported for OGD-500, OGD-575, OYD-500. OXD-525 supported for 3 months at room temp. No significant change in microbial content. |
| Interfering Substances (eSensor Test) | 100% correct calls. | 100% correct calls on first-pass for all tested endogenous and exogenous substances. |
2. Sample Size Used for the Test Set and Data Provenance
- Performance Characteristics (Initial):
- OGD-500: 450 samples from 245 unique donors.
- OXD-525 & OYD-500: Subset of 45 donors.
- OGD-575: Subset of 43 donors.
- Sample Volume Tolerance Study: 240 samples using OGD-500.
- Reproducibility Study: 3 samples from each of 10 donors (total 30 samples collected, tested in triplicate by 4 operators, leading to 354-360 data points for yield/concentration, and 87-90 samples per SNP per operator for eSensor test).
- Post-Collection Sample Stability: 30 donors, each collecting four saliva samples for each of the 3 specified Oragene Dx formats (total 360 samples initially). A sub-population of 564 DNA samples across all time-points were tested on the eSensor® Warfarin Sensitivity Saliva Test.
- Interfering Substances Study: Samples from donors with known genotypes (exact number not specified beyond "samples").
Data Provenance: The document does not explicitly state the country of origin for the donors or samples. The study appears to be prospective in nature, as samples were "collected" for the purpose of the studies described (e.g., "samples were collected using OGD-500," "30 donors each self-collect four saliva samples").
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications
- The document does not specify the number of experts or their qualifications for establishing the ground truth of the genetic information (e.g., Warfarin Sensitivity SNPs) used with the eSensor® Warfarin Sensitivity Saliva Test. The "known genotypes" mentioned in the interfering substances study imply that the ground truth for the genetic markers was pre-established for the donors. The "Correct Calls" refer to the agreement with these known genotypes.
4. Adjudication Method for the Test Set
- The document does not describe an explicit adjudication method for discrepancies in the eSensor® Warfarin Sensitivity Saliva Test results. Instead, it mentions "re-testing" for initial no-calls. For instance, in the reproducibility study, "46 first-run no-calls were due to two runs... invalidated due to DNA Contamination Monitor (DCM) failures," and "The other first-pass no calls were low signal... positive control failure... and contradictory score." These suggest technical reasons for initial non-results, which were then resolved by re-testing. One incorrect call was "due to operator error resolved upon investigation," implying an internal review process rather than an independent expert adjudication of the initial assay result.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No, an MRMC comparative effectiveness study was not explicitly done in the context of human readers improving with AI vs. without AI assistance. This device is a sample collection kit, not an AI diagnostic tool that assists human readers.
6. Standalone Performance Study (Algorithm Only)
- Yes, a standalone performance study was done in the sense that the extracted DNA from the Oragene·Dx device was tested directly on the eSensor® Warfarin Sensitivity Saliva Test, and the results (correct calls, incorrect calls, no-calls) were reported for the device's output. The performance of the Oragene·Dx device in preparing samples suitable for subsequent molecular diagnostic testing is evaluated objectively based on the accuracy of the eSensor test. This is considered "standalone" for the sample collection device's function as its "output" (DNA) is assessed by a subsequent analytical device without human interpretation of its own performance.
7. Type of Ground Truth Used
- The ground truth used for evaluating the performance of the extracted DNA on the eSensor® Warfarin Sensitivity Saliva Test was known genotypes for the relevant SNPs (2C92, 2C93, VKORC1). This implies that the genetic information of the donors was determined by a reliable, presumably validated, method prior to the study.
8. Sample Size for the Training Set
- The document describes performance evaluation studies but does not mention a training set as this is a sample collection device, not a machine learning algorithm that requires training. The studies described are validation studies for the device's performance characteristics.
9. How the Ground Truth for the Training Set Was Established
- As there is no mention of a training set or machine learning algorithm, this question is not applicable. The "ground truth" (known genotypes) for the performance evaluation was established beforehand for the test samples through undisclosed methods.
§ 862.1675 Blood specimen collection device.
(a)
Identification. A blood specimen collection device is a device intended for medical purposes to collect and to handle blood specimens and to separate serum from nonserum (cellular) components prior to further testing. This generic type device may include blood collection tubes, vials, systems, serum separators, blood collection trays, or vacuum sample tubes.(b)
Classification. Class II.