(255 days)
The eSensor® Warfarin Sensitivity Saliva Test is an in vitro diagnostic for the detection and genotyping of the *2 and *3 alleles of the cytochrome P450 (CYP450) 2C9 gene locus and the Vitamin K epoxide reductase C1 (VKORC1) gene promoter polymorphism (-1639G>A) from genomic DNA extracted from human saliva samples collected using the Oragene® Dx and ORAcollect® Dx devices, as an aid in the identification of patients at risk for increased warfarin sensitivity.
The eSensor® XT-8 instrument is an in vitro diagnostic device intended for genotyping multiple mutations or polymorphisms in an amplified DNA sample utilizing electrochemical detection technology.
The kit consists of the eSensor® Warfarin Sensitivity Saliva Test cartridge, the eSensor® Warfarin Sensitivity Saliva Test amplification reagents (including PCR mix and DNA polymerase), the eSensor® Warfarin Sensitivity Saliva Test detection reagents (including exonuclease, probes and hybridization buffer ingredients) and the eSensor® XT-8 System. One eSensor® Warfarin Sensitivity Saliva Test Kit has sufficient materials for 24 tests.
The provided document, a 510(k) summary for the eSensor® Warfarin Sensitivity Saliva Test, details performance data primarily focused on a new specimen collection kit (ORAcollect®·Dx Device) and its impact on the existing device's performance. The study aims to demonstrate that incorporating this new collection kit does not compromise the accuracy or reliability of the Warfarin Sensitivity Saliva Test.
Here's an analysis of the acceptance criteria and study findings:
1. Table of Acceptance Criteria and Reported Device Performance
The document doesn't explicitly state 'acceptance criteria' in terms of specific numerical thresholds for accuracy, reproducibility, or call rates. However, the studies consistently aim for 100% agreement with the ground truth (bi-directional sequencing), and 100% correct calls with 0% incorrect calls. The "Method Comparison" section indicates an aspiration for high concordance and call rate.
| Metric (Implicit Acceptance Criterion) | Reported Device Performance |
|---|---|
| Reproducibility | |
| Sample-to-Sample, Lot-to-Lot, Day-to-Day, Operator-to-Operator Agreement with Sequencing (CYP2C92, CYP2C93, VKOR) | 100% Agreement (60/60 correct calls across 3 operators for each SNP, totaling 180 successful calls out of 180 attempts for each SNP, or 120/120 for each donor when considering total calls). |
| Multi-center Reproducibility Agreement with Sequencing | 100% Agreement (30/30 for Site 1, 30/30 for Site 2, 29/29 for Site 3, after final pass, excluding one sample that did not meet input criteria). |
| Method Comparison | |
| Overall Concordance with DNA Sequencing | 99.4% concordance for all polymorphisms (after retests). |
| First-pass Call Rate | 98.1% |
| Final Pass Call Rate | 99.4% |
| % Agreement per Genotype (post-retest) | 2C9*2: 99.0% (wt/wt), 100.0% (wt/2), 100.0% (2/2) **2C93: 100.0% (wt/wt), 95.0% (wt/*3), 100.0% (*3/*3) VKORC1: 98.4% (G/G), 100.0% (G/A), 100.0% (A/A) (Note: Lower 95% LCBs for less common genotypes due to smaller sample sizes). |
| Interference Studies | |
| Endogenous Interfering Substances Agreement with Sequencing | 100% Agreement (for Amylase, Hemoglobin, IgA, Total Protein - all 14 samples tested per substance). |
| Exogenous Interfering Substances Agreement with Sequencing | 100% Agreement (for Eating, Drinking, Chewing Gum, Smoking, Mouthwash, Brushing Teeth at immediate and 30-minute time points - sample sizes ranging from 5 to 9 per group). |
2. Sample Sizes and Data Provenance
-
Reproducibility (Sample-to-Sample, Lot-to-Lot, Day-to-Day, Operator-to-Operator):
- Test set sample size: 10 donors, with 3 samples each (total 30 samples collected). These were processed by 3 operators, with genotyping data evaluated for each operator for each of the 3 SNPs. This implies 20 tests per SNP per operator (based on the "20" under "Samples Tested" for each SNP for each operator), totaling 60 tests per SNP across all operators, or 120 calls per SNP when considering all samples and operators for the "Summary of Results by Sample and Genotype" table.
- Data Provenance: Not explicitly stated, but likely prospective and from a controlled lab environment.
-
Multi-center Reproducibility:
- Test set sample size: 30 donors. Multiple saliva samples collected from each.
- Data Provenance: Saliva samples were collected from 3 sites. Two sites were described as "professional setting" with "supervised collections," and the third site had "unsupervised collections." One sample from each donor was transported to three independent sites for extraction. All eSensor Warfarin Sensitivity Saliva testing was conducted at Site 1. This suggests a prospective data collection design, with samples from multiple (unspecified) locations. No country of origin is mentioned.
-
Method Comparison:
- Test set sample size: 156 saliva samples.
- Data Provenance: Not explicitly stated, but implies a prospective or retrospectively collected set of human saliva samples. No country of origin is mentioned.
-
Interfering Substances (Endogenous):
- Test set sample size: 14 donors, each providing 4 saliva samples.
- Data Provenance: Not explicitly stated, but likely prospective, controlled lab study.
-
Interfering Substances (Exogenous):
- Test set sample size: Varied per activity, ranging from 5 to 9 donors per activity group. Each donor provided samples at two time-points (immediate and 30 minutes post-activity).
- Data Provenance: Not explicitly stated, but likely prospective, controlled lab study.
3. Number of Experts and Qualifications for Ground Truth
The ground truth for all studies was established by bi-directional DNA sequencing. This is a laboratory-based method, not typically requiring "experts" in the sense of clinical specialists. The interpretation of sequencing results is a standard molecular biology technique. No specific number of experts or their qualifications (e.g., geneticists, molecular biologists) are mentioned for establishing the ground truth, as it's assumed to be a direct, objective measurement.
4. Adjudication Method for the Test Set
The studies used bi-directional DNA sequencing as the gold standard, not a human expert adjudication process. The agreement was calculated directly between the device's genotypes and the sequencing results. If there were discrepancies in the initial device results (e.g., initial miscalls or no-calls in the method comparison), retests were performed. For instance, in the method comparison, two miscalls were attributed to "operator error (sample mix-up) occurring during the first XT8 testing" and one remaining no-call to "an operator error at the purification step." This suggests an internal investigation and re-testing process rather than an external adjudication panel.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No Multi-Reader Multi-Case (MRMC) comparative effectiveness study was done. This device is a diagnostic test for genotyping, not an imaging device or a system requiring human interpretation with or without AI assistance. Therefore, the concept of "readers improving with AI vs. without AI" is not applicable here. The device itself performs the genotyping.
6. Standalone Performance Study
Yes, a standalone performance study was done. All the performance data described (reproducibility across operators/sites, method comparison with sequencing, and interfering substances studies) directly assesses the performance of the eSensor® Warfarin Sensitivity Saliva Test (algorithm/device only, without human-in-the-loop performance influencing the genotyping call itself, though human operators are involved in sample preparation and running the test). The percentage agreement and call rates reflect the direct output of the device compared to the ground truth.
7. Type of Ground Truth Used
The primary ground truth used for all studies was bi-directional DNA sequencing. This is a highly accurate molecular method for determining genetic sequences and polymorphisms (genotypes).
8. Sample Size for the Training Set
The document is a 510(k) summary for a labeling modification (addition of a new specimen collection kit) to an already cleared device. It primarily presents validation data for the continued performance of the device with the new collection kit. It does not mention a "training set" for the eSensor® Warfarin Sensitivity Saliva Test itself, as this device likely relies on established molecular biology principles and probes designed against known genetic targets, rather than machine learning algorithms that require extensive training data. It's a deterministic diagnostic test, not an AI model that learns from data in the way a computer vision algorithm would.
9. How Ground Truth for the Training Set Was Established
As noted above, the concept of a "training set" doesn't directly apply in the context of this device. The device's design is based on known genetic sequences and electrochemical detection rather than a machine learning model. The validation studies verify its performance against the established ground truth of bi-directional DNA sequencing.
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Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002
May 26, 2016
GENMARK DIAGNOSTICS, INCORPORATED ALAN MADERAZO VP, QUALITY, REGULATORY, & CLINICAL AFFAIRS 5964 LA PLACE COURT CARLSBAD CA 92008
Re: K152612
Trade/Device Name: eSensor Warfarin Sensitivity Saliva Test Regulation Number: 21 CFR §862.3360 Regulation Name: Drug Metabolism Enzyme Genotyping Test Regulatory Class: II Product Code: ODW, ODV, NSU Dated: April 21, 2016 Received: April 22, 2016
Dear Mr. Maderazo:
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 (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. 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.
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 Parts 801 and 809); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
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If you desire specific advice for your device on our labeling regulations (21 CFR Parts 801 and 809), please contact the Division of Industry and Consumer Education at its toll-free number (800) 638 2041 or (301) 796-7100 or at its Internet address
http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm. Also, please note the regulation entitled. "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to
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You may obtain other general information on your responsibilities under the Act from the Division of Industry and Consumer Education at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address
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Sincerely yours.
Courtney H. Lias -S
Courtney H. Lias, Ph.D. Director Division of Chemistry and Toxicology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health
Enclosure
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Indications for Use
510(k) Number (if known) K152612
Device Name eSensor® Warfarin Sensitivity Saliva Test
Indications for Use (Describe)
The eSensor® Warfarin Sensitivity Saliva Test is an in vitro diagnostic for the detection and genotyping of the *2 and *3 alleles of the cytochrome P450 (CYP450) 2C9 gene locus and the Vitamin K epoxide reductase C1 (VKORC1) gene promoter polymorphism (-1639G>A) from genomic DNA extracted from human saliva samples collected using the Oragene® Dx and ORAcollect® Dx devices, as an aid in the identification of patients at risk for increased warfarin sensitivity.
The eSensor® XT-8 instrument is an in vitro diagnostic device intended for genotyping multiple mutations or polymorphisms in an amplified DNA sample utilizing electrochemical detection technology.
| 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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510(k) SUMMARY
eSensor® Warfarin Sensitivity Saliva Test
Attached is a 510(k) summary as described in 21 CFR 807.92
Sponsor Information
| Submitted By: | |
|---|---|
| Name: | GenMark Diagnostics, Incorporated |
| Address: | 5964 La Place CourtCarlsbad, CA 92008(760) 448-4300 |
| Company Contact: | |
|---|---|
| Contact: | Alan Maderazo, Ph.D., RAC |
| VP, Quality Assurance, Regulatory and Clinical Affairs | |
| Phone: | 760-448-4308 |
| Fax: | 760-683-6961 |
| Email: | al.maderazo@genmarkdx.com |
Date Prepared: May 23, 2016
General Information
Trade Name: eSensor® Warfarin Sensitivity Saliva Test
eSensor® Warfarin Sensitivity Saliva Test
| Device Description | Drug metabolizing enzyme genotyping testProthrombin time test, |
|---|---|
| Medical Specialty | Hematology |
| Product Code | ODW, ODV |
| Device Class | 2 |
| Regulation number | 862.3360, 864.7750 |
Instrument (XT-8)
| Device Description | Instrumentation for clinical multiplex test systems |
|---|---|
| Medical Specialty | Clinical Chemistry |
| Product Code | NSU |
| Device Class | 2 |
| Regulation number | 862.2570 |
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Predicate device: eSensor® Warfarin Sensitivity Saliva Test, K110786
This premarket application is a labeling modification to a previously cleared device: addition of a new specimen collection kit.
Device Description
The kit consists of the eSensor® Warfarin Sensitivity Saliva Test cartridge, the eSensor® Warfarin Sensitivity Saliva Test amplification reagents (including PCR mix and DNA polymerase), the eSensor® Warfarin Sensitivity Saliva Test detection reagents (including exonuclease, probes and hybridization buffer ingredients) and the eSensor® XT-8 System. One eSensor® Warfarin Sensitivity Saliva Test Kit has sufficient materials for 24 tests.
The polymorphisms genotyped by the eSensor® Warfarin Sensitivity Saliva Test are shown in Table 1.
| Table 1. Polymorphisms in the eSensor® Warfarin SensitivitySaliva Test Panel | |
|---|---|
| Polymorphism | Allele† |
| CYP450 2C9 430 C>T | *2 |
| CYP450 2C9 1075A>C | *3 |
| VKORC1 -1639G>A | GG, GA, or AA |
| † CYP450 2C9 allele designations as established by the HumanCytochrome P450 (CYP) Allele Nomenclature Committee(http://www.cypalleles.ki.se/cyp2c9.htm). The major alleles ofthese polymorphisms are designated as *1. |
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Intended Use
The eSensor® Warfarin Sensitivity Saliva Test is an in vitro diagnostic for the detection and genotyping of the *2 and *3 alleles of the cytochrome P450 (CYP450) 2C9 gene locus and the Vitamin K epoxide reductase C1 (VKORC1) gene promoter polymorphism (-1639G>A) from genomic DNA extracted from human saliva samples collected using the Oragene®Dx and ORAcollect®•Dx devices, as an aid in the identification of patients at risk for increased warfarin sensitivity.
The eSensor® XT-8 instrument is an in vitro diagnostic device intended for genotyping multiple mutations or polymorphisms in an amplified DNA sample utilizing electrochemical detection technology.
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Comparison to Predicate
This premarket application is a labeling modification to a previously cleared device: addition of a new specimen collection kit (the ORAcollect®·Dx Device manufactured by DNA Gentek). The data supporting the use of this specimen collection kit are provided in K152464.
| Similarities | ||
|---|---|---|
| Item | Proposed Device | Predicate Device (K110786) |
| Intended Use | For the detection and genotyping of the *2 and*3 alleles of the cytochrome P450 (CYP450) 2C9 gene locus and the Vitamin K epoxide reductase C1 (VKORC1) gene promoter polymorphism (-1639G>A) | Same |
| Indications for Use | as an aid in the identification of patients at risk for increased warfarin sensitivity | Same |
| Device Components | Test cartridge, amplification reagents (including PCR mix and DNA polymerase), detection reagents (including exonuclease, probes and hybridization buffer ingredients) and the eSensor® XT-8 System. | Same |
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Performance Data
The following studies were conducted to validate the performance of the ORAcollect-Dx device:
- Reproducibility .
- . Method Comparison
- Interfering Substances .
Summaries of the study results are provided. The formal study reports are provided in K152464.
Reproducibility
Reproducibility of the performance of the ORAcollect-Dx device was evaluated to establish multi-center (site-to-site), lot-to-lot, sample-to-sample, day-to-day extraction and operator-tooperator reproducibility.
Sample-to-Sample, Lot-to-Lot, Day-to-Day and Operator-to-Operator Reproducibility
Three samples (collected using three lots of ORAcollect-Dx format OCD-100) from each of ten donors, were processed by three different operators on multiple days. Each operator extracted DNA from each sample using the same Qiagen QIAamp DNA mini kit, followed by determination of DNA concentration and A260/A280 ratio for all samples. Three operators tested the extracted DNA samples on the eSensor Warfarin Saliva Sensitivity Test. Genotyping data was evaluated after first-pass results and all samples were concordant to bi-directional sequencing.
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| SNP | SamplesTested | CorrectCalls | IncorrectCalls | No-Calls | %Agreement | |
|---|---|---|---|---|---|---|
| Operator1 | 2C9*2 | 20 | 20 | 0 | 0 | 100% |
| 2C9*3 | 20 | 20 | 0 | 0 | 100% | |
| VKOR | 20 | 20 | 0 | 0 | 100% | |
| Operator2 | 2C9*2 | 20 | 20 | 0 | 0 | 100% |
| 2C9*3 | 20 | 20 | 0 | 0 | 100% | |
| VKOR | 20 | 20 | 0 | 0 | 100% | |
| Operator3 | 2C9*2 | 20 | 20 | 0 | 0 | 100% |
| 2C9*3 | 20 | 20 | 0 | 0 | 100% | |
| VKOR | 20 | 20 | 0 | 0 | 100% | |
| Combined | 2C9*2 | 60 | 60 | 0 | 0 | 100% |
| 2C9*3 | 60 | 60 | 0 | 0 | 100% | |
| VKOR | 60 | 60 | 0 | 0 | 100% |
Summary of Results Stratified by Operator
Summary of Results by Sample and Genotype
| Genotype by sequencing | Number ofSamples Testedby eSensor | Number ofCorrect Calls | %Agreement | |||
|---|---|---|---|---|---|---|
| Donor ID | 2C9*2 | 2C9*3 | VKOR | |||
| REP01 | WT | WT | HET | 12 | 12 | 100% |
| REP02 | HET | WT | WT | 12 | 12 | 100% |
| REP03 | HET | WT | MUT | 12 | 12 | 100% |
| REP04 | HET | WT | WT | 12 | 12 | 100% |
| REP05 | HET | HET | HET | 12 | 12 | 100% |
| REP06 | WT | MUT | MUT | 12 | 12 | 100% |
| REP07 | MUT | WT | WT | 12 | 12 | 100% |
| REP08 | HET | HET | HET | 12 | 12 | 100% |
| REP09 | WT | WT | HET | 12 | 12 | 100% |
| REP10 | MUT | WT | WT | 12 | 12 | 100% |
| Total | 120 | 120 | 100% |
Multi-center reproducibility
Thirty (30) donors collected multiple saliva samples each from 3 sites; 2 of the 3 sites were in a professional setting and had supervised collections compared to unsupervised collections at the third site. The 30 donors were selected to encompass a diverse genotype distribution for CYP2C9 and VKORC1 genotype distribution. After sample collection, one sample from each donor was transported at ambient temperatures to three (3) independent sites. Each site had one operator for a study total of 3 operators. Following sample extraction using the QIAamp DNA
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mini kit, all purified genomic DNA samples were tested for DNA concentration, yield and A260/A280 at the sites where they were extracted. All purified genomic DNA samples were transported to Site 1 for testing on the eSensor Warfarin Sensitivity Saliva Test where one extracted DNA aliquot from each sample from each site was tested on the Warfarin assay, excluding a single sample that did not meet assay input criteria. When data from all three sites are combined, only one (1) sample did not meet the eSensor Warfarin Sensitivity Saliva Test input requirements. After final pass there was 100% agreement (89/89) with bidirectional sequencing.
Summary of Results by Site (Final Pass)
| eSensor Warfarin Sensitivity Saliva Test*** | |||||
|---|---|---|---|---|---|
| Site of sampleextraction* | Number ofSamples Tested** | CorrectCalls | IncorrectCalls | No-calls | % Agreement with Bi-directional Sequencing |
| Site 1 | 30 | 30 | 0 | 0 | 100% |
| Site 2 | 30 | 30 | 0 | 0 | 100% |
| Site 3**** | 29 | 29 | 0 | 0 | 100% |
※ DNA extraction using QIAGEN QIAMP DNA Mini kit.
** Donor genotype representation: CYP2C9 (*1, *2, *3); VKOR
*** All eSensor Warfarin Sensitivity Saliva testing was conducted at Site 1 (by Operator 1). Only sample aliquots meeting the WST input criteria were tested.
**** One sample was excluded from WST testing
Method Comparison
In a method comparison study, a total of 156 saliva samples were genotyped using the eSensor® Warfarin Sensitivity Saliva Test and DNA sequencing. The genotyping calls by the eSensor® Warfarin Sensitivity Saliva Test method were 99.4% concordant with genotypes determined by DNA sequencing for all polymorphisms, with a 98.1% first-pass call rate and 99.4% final pass call rate. The following tables summarize the results of the method comparison study after retests.
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| eSensor® Warfarin Sensitivity Saliva Test Method Comparison After Retest | |||
|---|---|---|---|
| DNA Sequencing Result | 2C9 wt/wt | 2C9 wt/*2 | 2C9*2/*2 |
| Correct Calls | 104 | 46 | 5 |
| No-Calls* | 1 | 0 | 0 |
| Miscalls | 0 | 0 | 0 |
| %Agreement | 99.0% | 100.0% | 100.0% |
| 95% LCB | 95.6% | 93.7% | 54.9% |
| DNA Sequencing Result | 2C9 wt/wt | 2C9 wt/*3 | 2C9 *3/*3 |
| Correct Calls | 135 | 19 | 1 |
| No-Calls* | 0 | 1 | 0 |
| Miscalls | 0 | 0 | 0 |
| %Agreement | 100.0% | 95.0% | 100.0% |
| 95% LCB | 97.8% | 78.4% | 5.0% |
| DNA Sequencing Result | VKORC1G/G | VKORC1G/A | VKORC1A/A |
| Correct Calls | 63 | 71 | 21 |
| No-Calls* | 1 | 0 | 0 |
| Miscalls | 0 | 0 | 0 |
| %Agreement | 98.4% | 100.0% | 100.0% |
| 95% LCB | 92.8% | 95.9% | 86.7% |
| On First pass there were 2 miscalls due to operator error (sample mix-up) occurring during the first XT8 testing. |
- After Final pass, one no call remained unresolved, likely due to an operator error at the purification step of the protocol.
Interfering Substances
Interfering substances including salivary α-amylase, hemoglobin, immunoglobulin A (IgA) and total protein were spiked into saliva samples at the highest amounts found in literature. 14 donors provided four saliva samples each which were each spiked with one of the four interfering substances. There was 100% agreement between the eSensor® Warfarin Sensitivity Saliva Test results and bidirectional DNA sequencing for all test substances after re-test, demonstrating no effect of any interfering substances on genotyping.
| Substance | SamplesTested | CorrectCalls | IncorrectCalls | No-Calls | %Agreement |
|---|---|---|---|---|---|
| Amylase | 14 | 14 | 0 | 0 | 100% |
| Hemoglobin | 14 | 14 | 0 | 0 | 100% |
| IgA | 14 | 14 | 0 | 0 | 100% |
| Total Protein | 14 | 14 | 0 | 0 | 100% |
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Effect of Exogenous Interfering Substances:
Potentially interfering exogenous substances introduced into saliva samples through various activities (eating, drinking, chewing gum, using mouthwash, smoking and brushing teeth) were tested. Each activity group was composed of five to nine donors who each provided samples immediately after activity and 30 minutes post-activity. There was 100% agreement between the eSensor® Warfarin Sensitivity Saliva Test results and bidirectional DNA sequencing for all activities tested in first pass, demonstrating no effect of any interfering substances on genotyping.
| Activity | Time-point | SamplesTested | CorrectCall | IncorrectCall | No-call | % Agreement |
|---|---|---|---|---|---|---|
| Eating | Immediate | 8 | 8 | 0 | 0 | 100% |
| 30 minutes | 9 | 9 | 0 | 0 | 100% | |
| Drinking | Immediate | 8 | 8 | 0 | 0 | 100% |
| 30 minutes | 9 | 9 | 0 | 0 | 100% | |
| Chewing Gum | Immediate | 7 | 7 | 0 | 0 | 100% |
| 30 minutes | 7 | 7 | 0 | 0 | 100% | |
| Smoking | Immediate | 5 | 5 | 0 | 0 | 100% |
| 30 minutes | 5 | 5 | 0 | 0 | 100% | |
| Mouthwash | Immediate | 5 | 5 | 0 | 0 | 100% |
| 30 minutes | 5 | 5 | 0 | 0 | 100% | |
| Brushing Teeth | Immediate | 9 | 9 | 0 | 0 | 100% |
| 30 minutes | 9 | 9 | 0 | 0 | 100% |
Conclusion
The above test results support the safety and effectiveness of the eSensor® Warfarin Sensitivity Saliva Test on the eSensor® XT-8 System, and demonstrate substantial equivalence to the predicate device.
§ 862.3360 Drug metabolizing enzyme genotyping system.
(a)
Identification. A drug metabolizing enzyme genotyping system is a device intended for use in testing deoxyribonucleic acid (DNA) extracted from clinical samples to identify the presence or absence of human genotypic markers encoding a drug metabolizing enzyme. This device is used as an aid in determining treatment choice and individualizing treatment dose for therapeutics that are metabolized primarily by the specific enzyme about which the system provides genotypic information.(b)
Classification. Class II (special controls). The special control is FDA's guidance document entitled “Class II Special Controls Guidance Document: Drug Metabolizing Enzyme Genotyping Test System.” See § 862.1(d) for the availability of this guidance document.